Spotlight On...

Biological control of weeds.

The potential for weed biological control is increasingly being recognized, and a greater number of weeds, including those of agricultural importance and alien species with an impact on conservation, are being targeted for control using biological agents. This spotlight highlights the variety of resources that are available from CABI on the topic of weed biological control.

Details of the following books are available at the Online Bookshop:

Other book titles on weed science and biological control can browsed at the Online Bookshop.

A selection of abstracts on the biological control of weeds taken from Weed Abstracts is given below.

Related items included in PEST CABWeb®:

  • Biocontrol News and Information, which includes free news on weeds biocontrol.
  • The following news items have been covered in recent editions:

    March 2000

    Water hyacinth (Eichhornia crassipes) in Africa
    Japanese knotweed (Reynoutria japonica/Fallopia japonica) in the UK

    December 1999

    Opuntia stricta and Harrisia martinii in South Africa
    Chromolaena odorata in Indonesia and South Africa
    Ageratina riparia in New Zealand
    Campuloclinium macrocephalum in South Africa
    Chrysanthemoides monilifera in Australia and New Zealand
    Hieracium pilosella in New Zealand
    Clematis vitalba in New Zealand
    Asparagus asparagoides in Australia and New Zealand
    Macfadyena unguis-cati in South Africa
    Solanum mauritianum in South Africa

    June 1999

    Parkinsonia aculeata in Australia
    Bruchidius villosus -nontarget effects against Chamaecytisus palmensis in New Zealand
    RFLP, RAPD and AFLP techniques in weed biocontrol
    Spartina anglica in western USA
    Release methods for fungal biocontrol agents

    March 1999

    Caulerpa taxifolia in the Mediterranean Sea
    Mimosa pigra and Prosopis species in Australia
    Mimosa invisa in Fiji
    Gaultheria shallon in the UK

    Reviews on the topic of weeds biocontrol are also available from Biocontrol News and Information.
  • Weed Abstracts
  • Both Weeds Abstracts and Biocontrol News and Information are now available via the internet with an extended backfile containing 10 years' of data.

  • Crop Protection Compendium - an encyclopaedic multimedia tool which contains datasheets on weeds and their natural enemies. The datasheets include distribution maps and illustrations. Some of the illustrations from the water hyacinth datasheet can be seen below.

CABI Bioscience

CABI Bioscience is actively involved in biological pest management. Details and the latest news of their research programmes, which include Weed Biological Control, Biopesticides and Biological Control of Invertebrate Pests, can be viewed at the CABI Biosciences website.

CABI Bioscience is also involved in the Japanese Knotweed Alliance, which seeks to promote the control of knotweed using biological predators and the Global Invasive Species Programme.


TI: Biological control of cyanobacteria: principles and possibilities.
CT: The ecological bases for lake and reservoir management. Proceedings of a symposium, Leicester, UK, 19-22 March 1996 [edited by Harper, D. M.; Brierley, B.; Ferguson, A. J. D.; Phillips, G.].
AU: Sigee, D. C.\ Glenn, R.\ Andrews, M. J.\ Bellinger, E. G.\ Butler, R. D.\ Epton, H. A. S.\ Hendry, R. D.
JN: Hydrobiologia
YR: 1999
VL: 395/396
PP: 161-172
LA: En
MS: 50 ref.
AA: School of Biological Sciences, University of Manchester, 1.800 Stopford Building, Oxford Road, Manchester, UK.
AB: A range of naturally occurring organisms are available for the biological control of cyanobacteria, including viruses, bacteria, fungi, actinomycetes [Actinomycetales] and Protozoa. Development of these organisms as biological control agents involves isolation from environmental samples, characterization of anti-cyanobacterial activity, microcosm and large-scale field experiments and final development of a biological control lake management strategy. Two groups of antagonists are considered in detail-Actinomycetales (Streptomyces exfoliatus, mode of action by production of a lytic agent) and Protozoa (Nuclearia delicatula and Nassula tumida, mode of action by predation), using algal lawn assays and liquid culture assays to assess the biological control potential of Actinomycetales and Protozoa, respectively. The effectiveness of biological control agents in the lake environment depends on a range of biological and physico-chemical factors. Various strategies can be implemented to optimize their activity.
DE: conferences\biological control\biological control agents\cyanobacteria\weeds\weed control\viruses\bacteria\fungi\Actinomycetales\reviews\Protozoa\Streptomyces exfoliatus\Nuclearia delicatula\Nassula tumida\lakes\Streptomyces
AN: 0W04901006

TI: Biological control of weeds in South Africa (1990-1998).
AU: Olckers, T.\ Hill, M. P. (Editors)
YR: 1999
PP: 182 pp.
BN: ISBN 0-620-24291-4
LA: En
MS: many ref., African Entomology Memoir No. 1
AA: ARC-Plant Protection Research Institute, South Africa.
AB: This memoir contains reviews covering 19 biological weed control programmes in South Africa. The following categories are featured: programmes where agents have been released for the first time since 1991, existing programmes where agents have been established for the first time, well-established programmes where the impact of the agents has been demonstrated or where new agents or biotypes have been released to augment those already established, and other established programmes where research on new candidate agents is ongoing, or where new associations have been exploited. Each paper considers the achievements, limitations and future prospects of these programmes. The Southern African Plant Invaders Atlas database and the influence of current initiatives upon the direction of biological control programmes, are also discussed.
DE: reviews\weeds\weed control\biological control\biological control agents\databases
GL: South Africa
AN: 0W04900840

TI: The initiation of a biological control programme against Macfadyena unguis-cati (L.) Gentry (Bignoniaceae) in South Africa.
CT: Biological control of weeds in South Africa (1990-1998) [edited by Olckers, T.; Hill, M. P.].
AU: Sparks, H. E.
YR: 1999
PP: 153-157
BN: ISBN 0-620-24291-4
LA: En
MS: 12 ref., African Entomology Memoir, No. 1
AA: ARC-Plant Protection Research Institute, Private Bag X134, Pretoria 0001, South Africa.
AB: The exotic cat's claw creeper, M. unguis-cati, was introduced into South Africa as an ornamental species and is in the early stages of invasion. Natural forests are particularly at risk and woodlands, plantations, orchards and disturbed areas are also invaded. The weed forms thick carpets that smother forest floors and canopies, killing canopy trees and understorey plants. Mechanical and chemical control methods are impractical and the weed was thus targeted for biological control. In 1996, a leaf-feeding tortoise beetle, Charidotis auroguttata, was opportunistically introduced from Venezuela. Following routine screening in quarantine, permission for the release of C. auroguttata in South Africa was granted in February 1999. Release of C. auroguttata and other agents may alleviate troublesome infestations and preempt further invasion.
DE: biological control\biological control agents\weeds\weed control\forests\invasions\ornamental plants\Charidotis auroguttata\reviews\Chrysomelidae\Macfadyena unguis-cati\Bignoniaceae
GL: South Africa
AN: 0W04900516\0F06102671

TI: Plant population ecology and biological control: Acacia nilotica as a case study.
AU: Kriticos, D.\ Brown, J.\ Radford, I.\ Nicholas, M.
JN: Biological Control
YR: 1999
VL: 16
NO: 2
PP: 230-239
LA: En
MS: 2 pp of ref.
AA: University of Queensland, St. Lucia, QLD 4072, Australia.
AB: The distribution of Acacia nilotica worldwide is outlined, and its preferred habitats and weed status in Australia are described. The status of biocontrol programmes against it in Australia is summarized. Its life history and dispersal mechanisms are reviewed with the aim of understanding the relative weaknesses of each life stage and identifying stages and weaknesses that might be exploited in a biocontrol programme. In this context, the following important attributes were identified: most flowers are aborted unfertilized; many pods can be aborted under adverse conditions; cattle are the primary vectors for seed dispersal; A. nilotica benefits from cattle dispersal; dispersed seeds are highly clumped; seedlings and juvenile trees compete for resources and undergo self-thinning; and mortality rates for juvenile and adult trees are low compared with those for seedlings. The implications of these attributes for the biocontrol of this weed in Australia are assessed. It is argued that the seedling and juvenile stages appears to be the best target for biocontrol attempts.
DE: Acacia nilotica\weeds\weed control\biological control\woody weeds\geographical distribution\population ecology\habitats\life history\spread\flowers\cattle\seed dispersal\plant competition\mortality\growth stages
GL: Australia
AN: 0W04900585\7G02301087\0F06102665

TI: Implications of induced resistance to pathogens and herbivores for biological weed control.
CT: Induced plant defenses against pathogens and herbivores biochemistry, ecology, and agriculture [edited by Agrawal, A. A.; Tuzun, S.; Bent, E.].
AU: Zidack, N. K.
YR: 1999
PP: 371-378
BN: ISBN 0-89054-242-2
LA: En
MS: 33 ref.
AA: Department of Plant Sciences, Montana State University, Bozeman, MT 59717, USA.
AB: Biotic or abiotic elicitation of induced resistance in the field may thwart efforts to use biocontrol agents. A review is presented of the small body of literature dealing explicitly with defence mechanisms in weeds, and literature on induced resistance in crop plants and model systems is related to biological weed control.
DE: pest resistance\weeds\plant pathogens\herbivores\weed control\biological control\crops
AN: 0W04900584

TI: Seasonal factors affecting the control of annual bluegrass (Poa annua L.) with Xanthomonas campestris pv. poae (JT-P482).
AU: Imaizumi, S.\ Tateno, A.\ Miyamoto, D.\ Morita, K.\ Fujimori, T.
JN: Biological Control
YR: 1999
VL: 16
NO: 1
PP: 18-26
LA: En
MS: 20 ref.
AA: Plant Protection Research Laboratory, Japan Tobacco Inc., 6-2 Umegaoka, Aoba-ku, Yokohama, Kanagawa 227, Japan.
AB: Studies were carried out in Japan to determine the optimum timing for the application of Xanthomonas campestris pv. poae [X. translucens pv. poae] to control annual bluegrass (Poa annua). Changes in the fresh weight, seedhead production and bacterial populations in P. annua plants treated with X. translucens pv. poae in different months were compared in pot experiments set in the field in 1994-95 and 1996-97. More than 75% cumulative seedhead suppression was achieved by the October, November and February treatments. Bacterial populations in P. annua plants increased to 10(9) colony forming units (c.f.u.)/g of fresh weight (FW) between 1 and 3 months in every application timing in 1996-97, but the best control was obtained when maximum bacterial numbers were reached within 1 month of treatment (in the October and February-April treatments). The differences in efficacy caused by different application timings (autumn or spring) were compared in different turfs in small-scale field trials in 1994-95 and 1995-96. Autumn and spring treatments were highly effective in two Kohrai (Zoysia matrella) turfs and in Kentucky bluegrass (Poa pratensis) turf. However control of P. annua was slower in bentgrass (Agrostis palustris [A. stolonifera var. palustris]) turf. October and/or March treatments effectively inhibited seedhead production, but the April treatment was too late to prevent seed scattering. It is concluded that the optimum timing of treatments is: application in early autumn (October) when the relatively high temperatures can accelerate bacterial multiplication, which should ensure bacterial survival throughout the winter; and/or application in early spring (February to March), just before seed ripening, to avoid seed scattering and to control newly emerged plants.
DE: Poa annua\weed control\Poa\Xanthomonas\Xanthomonas translucens pv. poae\biological control\plant diseases\plant pathogens\plant pathogenic bacteria\biological control agents\weeds
GL: Japan
AN: 0W04900204

TI: Effect of Galerucella spp. on survival of purple loosestrife (Lythrum salicaria) roots and crowns.
AU: Katovich, E. J. S.\ Becker, R. L.\ Ragsdale, D. W.
JN: Weed Science
YR: 1999
VL: 47
NO: 3
PP: 360-365
LA: En
MS: 29 ref.
AA: Department of Agronomy and Plant Genetics, University of Minnesota, St. Paul, MN 55108, USA.
AB: Starch levels, used as a measure of plant stress, were not consistently reduced in root or crown tissue of purple loosestrife plants after 2 yr of severe Galerucella calmariensis or Galerucella pusilla (Coleoptera: Chrysomelidae) defoliation in Minnesota, USA. Early in the season, defoliation by Galerucella spp. approached 100%, but the majority of Lythrum salicaria plants regrew by the end of August, resulting in an average reduction of 81% of the aboveground biomass compared with the control. The stress imposed by Galerucella spp. defoliation was less than that achieved from more severe stress imposed by mechanical shoot clipping at 2- or 4-week intervals from June to October. Both shoot-clipping treatments killed the majority of plants after one growing season. Galerucella spp. feeding reduced plant stature, which may reduce competitiveness. However, considering the extensive carbohydrate reserves present in the large woody crowns of Lythrum salicaria, it will require in excess of 2 yr of consistent, severe leaf defoliation to cause plant mortality. It is concluded that a combination of stresses, such as winter crown injury, or other biological control agents in addition to Galerucella leaf defoliation may be required for plant mortality.
DE: Galerucella\Lythrum\Lythrum salicaria\survival\biological control\biological control agents\Chrysomelidae\Coleoptera\defoliation\feeding\Galerucella pusilla\Galerucella calmariensis\insect pests\plant pests\weeds\weed control\woody weeds\stress factors\USA\Minnesota
GL: USA\Minnesota
AN: 0W04900202

TI: Development of a pesticide exclusion technique for assessing the impact of biological control agents for Chrysanthemoides monilifera.
AU: Adair, R. J.\ Holtkamp, R. H.
JN: Biocontrol Science and Technology
YR: 1999
VL: 9
NO: 3
PP: 383-390
LA: En
MS: 27 ref.
AA: Keith Turnbull Research Institute, CRC for Weed Management Systems, PO Box 48, Frankston 3199, Australia.
AB: Five pesticides were screened for their impact on seed production of C. monilifera [C. monoliferum] and two on the survival of the agent Comostolopsis germana, a shoot tip-feeding lepidopteran. The insecticides carbaryl, carbofuran, dimethoate and fluvalinate, and the fungicide benomyl, had no significant effect on seed production of C. monilifera when applied over a period of four months. Numbers of C. germana larvae were readily suppressed after three months by applications of fluvalinate or a mixture of carbaryl, carbofuran and dimethoate. Shoot growth was not affected by applications of carbaryl, dimethoate and benomyl. It is concluded that exclusion by pesticides of biological control agents is a valid method of measuring the impact of agents on C. monilifera.
DE: biological control\biological control agents\Chrysanthemoides moniliferum\pesticides\benomyl\carbaryl\carbofuran\dimethoate\fluval inate\insecticides\seed production\weeds\weed control\fungicides\comostolopsis germana\insects\Lepidoptera
AN: 0W04804956\7G02300540

TI: Fungi of Orobanche aegyptiaca in Nepal with potential as biological control agents.
AU: Thomas, H.\ Sauerborn, J.\ Müller-Stöver, D.\ Kroschel, J.
JN: Biocontrol Science and Technology
YR: 1999
VL: 9
NO: 3
PP: 379-381
LA: En
MS: 12 ref.
AA: Institute of Plant Production and Agroecology in the Tropics and Subtropics, University of Hohenheim, 70593 Stuttgart, Germany.
AB: A survey of pathogens of Orobanche aegyptiaca carried out in Nepal revealed that more than 70% of the fungal strains isolated from infected plants belonged to the genus Fusarium. Other fungi isolated were Acremonium fusidioides, Alternaria alternata, Cladosporium cladosporioides, Epicoccum nigrum, Mortierella alpina, Papulaspora sp., Phoma spp., Sordaria fimicola, Rhizoctonia sp., Trichoderma spp. and Trichothecium roseum.
DE: biological control\biological control agents\Nepal\Orobanche\Orobanche aegyptiaca\Acremonium\Alternaria\Cladosporium\Epicoccum\Mortierella\ pathogens\Phoma\Sordaria\Trichoderma\Trichothecium\Trichothecium roseum\weeds\parasitic weeds\Fusarium\acremonium fusidioides\Alternaria alternata\Cladosporium cladosporioides\Epicoccum nigrum\mortierella alpina\Papulaspora\sordaria fimicola\Rhizoctonia\plant pathogenic fungi\host plants
GL: Nepal
AN: 0W04804971

TI: Pathogenicity of Sclerotinia sclerotiorum on Ranunculus acris in dairy pasture.
AU: Cornwallis, L. J.\ Stewart, A.\ Bourdõt, G. W.\ Gaunt, R. E.\ Harvey, I. C.\ Saville, D. J.
JN: Biocontrol Science and Technology
YR: 1999
VL: 9
NO: 3
PP: 365-377
LA: En
MS: 13 ref.
AA: Soil, Plant & Ecological Sciences Division, PO Box 84, Lincoln University, New Zealand.
AB: Fifty-four isolates of Sclerotinia sclerotiorum from Ranunculus acris and other natural hosts were applied as mycelial-infested kibbled wheat onto 6 month-old R. acris plants in two glasshouse screening experiments. Most isolates (90%) did not differ in their pathogenicity towards R. acris. One isolate, S. sclerotiorum. G45, was selected based on its ability to cause severe disease and suppress regeneration of R. acris. A field experiment was conducted to determine the efficacy of S. sclerotiorum (G45) against R. acris in infested dairy pastures in the Takaka Valley, Golden Bay, New Zealand. Isolate G45 was formulated as a wettable powder and was applied as a slurry at 20 and 40 ml/plant in December 1995. After 10 weeks, regeneration from the crown of treated plants was apparent and a second application of S. sclerotiorum was made in February 1996. Best control of R. acris was obtained when the plants were inoculated in full flower in December. At the first time of treatment, the 40 ml application of S. sclerotiorum slurry reduced the total dry weight of R. acris by an average of 57%. The second application had no effect on total dry weight, possibly because moisture levels were not sufficient for S. sclerotiorum infection. This study confirmed S. sclerotiorum to be an aggressive pathogen of R. acris under both glasshouse and field conditions. As a result, this pathogen has potential as a mycoherbicide for R. acris.
DE: pastures\Ranunculus\Ranunculus acris\Sclerotinia\Sclerotinia sclerotiorum\weed control\host plants\New Zealand\pathogens\pathogenicity\plant pathogenic fungi\biological control\biological control agents\mycoherbicides\weeds\biological control
GL: New Zealand
AN: 0W04804892

TI: Mycobiota of Sorghum halepense (L.) Pers. and evaluation of capability of some species for biological control.
FT: Micobiota de Sorghum halepense (L.) Pers. y evaluacion de la capacidad de algunas especies para el control biologico.
AU: Bonilla, T.\ López, M. O.\ Mena, J.\ Rodríguez, K.\ Pérez, E.\ Tomás, Y.
JN: Revista de Protecció n Vegetal
YR: 1999
VL: 14
NO: 1
PP: 65-68
LA: Es
LS: en
MS: 23 ref.
AA: Instituto de Investigaciones de Sanidad Vegetal, 110#514, e/5ta.B y 5ta.F, Playa, Ciudad Habana, Cuba.
AB: Prospective studies on microorganisms were carried out to evaluate their capability for the future biological control of Sorghum halepense. Ten fungus species new to the weed in Cuba were recorded; the following appeared very frequently on the collected material: Cercospora sorghi, Colletotrichum graminicola, Phoma sorghina, Puccinia purpurea and Sporisorium cruentum. The pathogenicity of Bipolaris spicifera [Cochliobolus spicifer], B. bicolor, B. hawaiiensis, Curvularia cymbopogonis and C. comoriensis was tested; all of them were pathogenic to the weed. B. bicolor was the most pathogenic, causing the most severe symptoms on the leaves.
DE: Sorghum\Sorghum halepense\biological control\Bipolaris\Colletotrichum\weed control\Cuba\Curvularia\fungi\microorganisms\pathogenicity\Phoma\Puc cinia\Puccinia purpurea\Sporisorium\weeds\plant pathogenic fungi\biological control agents\biological control\Cercospora sorghi\Colletotrichum graminicola\Phoma sorghina\sporisorium cruentum\Cochliobolus spicifer\bipolaris bicolor\bipolaris hawaiiensis\curvularia cymbopogonis\curvularia comoriensis\host plants\hosts of plant diseases\plant diseases\plant pathogens
GL: Cuba
AN: 0W04804687

TI: Prospects for combining biological weed control with integrated crop production systems, and with sensitive management of alpine pastures in Switzerland.
AU: Ammon, H. U.\ Müller-Schärer, H.
JN: Zeitschrift für Pflanzenkrankheiten und Pflanzenschutz
YR: 1999
VL: 106
NO: 2
PP: 213-220
LA: En
LS: de
MS: 39 ref.
AA: Swiss Federal Institute of Technology (ETH), Institute of Plant Sciences, Group Phytopathology, CH-8092 Zürich, Switzerland.
AB: Two examples of integrating biological weed control into ecologically sound pest management systems in arable crops are described: combining living mulch and biological weed control in maize, and late weed control to favour predators and biological control of Amaranthus spp. in sugarbeet. The prospects for biological control in sensitive pasture management of alpine regions are discussed.
DE: biological control\weed control\cover crops\live mulches\maize\Zea mays\predators\beneficial insects\Amaranthus\weeds\sugarbeet\Beta vulgaris var. saccharifera\pastures\grassland management
GL: Switzerland
AN: 0W04804891\0Q05300207\0G07000745

TI: Weed control by Azolla in rice (Oryza sativa) fields of South 24-Parganas, West Bengal.
AU: Sahoo, S. K.\ Datta, B. K.
JN: Indian Journal of Agricultural Sciences
YR: 1999
VL: 69
NO: 4
PP: 283-284
LA: En
MS: 4 ref.
AA: Vivekananda Institute of Biotechnology, Nimpith, South 24-Parganas, West Bengal 734 338, India.
AB: The potential of Azolla caroliniana to control weeds and increase the yield of rice was investigated in West Bengal, India. Weeds observed in the rice fields were Chara sp., Nitella sp. and Hygrophila sp. In the control, the weeds reduced rice yields by 1.5 t/ha, accounting for about 40% of the average grain yield. Dual cropping with A. caroliniana increased the number of tillers/hill by 135-137%, chlorophyll content by 37-52% and grain yield by 60%. Copper sulfate and A. caroliniana both effectively controlled weeds during the wet season. The net profit with copper sulfate was 5902 Rs/ha and was 6019 Rs/ha with A. caroliniana. The additional profit increase was due to nitrogen replacement in the field. The ability of A. caroliniana to act as a biofertilizer and a weed control agent make the use of A. caroliniana superior to chemical control.
DE: weed utilization\aquatic weeds\weeds\weed control\biological control\Azolla caroliniana\rice\Oryza sativa\crop yield\Chara\Nitella\photosynthesis\nitrogen\profits\copper sulfate\herbicides\chemical control\Hygrophila\returns
GL: West Bengal\India
AN: 0W04804880\0Q05300293\0R04200107\7U02300520

TI: Allelopathy: principles, procedures, processes, and promises for biological control.
AU: Inderjit\ Keating, K. I.
JN: Advances in Agronomy
YR: 1999
VL: 67
PP: 141-231
LA: En
MS: 25 pp. of ref.
AA: Department of Agricultural Sciences (Weed Science), The Royal Veterinary and Agricultural University, DK-1871 Frederiksberg C, Copenhagen, Denmark.
AB: This review considers the allelopathic potential of noxious weeds, crops and plant residues, the characteristics of donor plants that favour allelopathic potential, the effects of stress, habitat and environmental factors on the expression of allelopathy, how allelopathy can be utilized in biological control programmes, the significance of additive effects of allelopathic compounds at low concentrations and problems in studying allelopathy.
DE: biological control\allelopathy\weeds\plant residues\stress\habitats\environmental factors\reviews
AN: 0W04804640\7E02002498

TI: Biological control of yellow toadflax (Linaria vulgaris) by Eteobalea serratella in peppermint (Mentha piperita).
AU: Volenberg, D. S.\ Hopen, H. J.\ Campobasso, G.
JN: Weed Science
YR: 1999
VL: 47
NO: 2
PP: 226-232
LA: En
MS: 40 ref.
AA: Department of Agronomy, University of Wisconsin-Madison, Madison, WI 53706, USA.
AB: Yellow toadflax (Linaria vulgaris) is an introduced ornamental perennial that has become a serious weed in Wisconsin peppermint production. Glyphosate is the only labeled herbicide that controls yellow toadflax in peppermint. Other control strategies, either mechanical or cultural, have little effect on the weed in solid stands of peppermint. Previous research has suggested that the root mining moth, Eteobalea serratella, may provide effective biological control of yellow toadflax. Therefore, experiments were conducted to determine the host specificity of E. serratella and to quantify E. serratella root mining of yellow toadflax. In larval and adult no-choice tests, E. serratella attacked only yellow toadflax. Other plant species collected from E. serratella's natural range were not attacked, neither those closely related to yellow toadflax in the family Scrophulariaceae, nor those closely related to peppermint in the family Labiatae. Root mining by E. serratella reduced root biomass by an average of 20% compared to untreated plants. Peppermint competition alone or in conjunction with root mining by E. serratella reduced root biomass 52 and 65%, respectively, compared to untreated plants under noncompetitive conditions. E. serratella is host specific for yellow toadflax and demonstrates potential as a biological control agent by contributing to the reduced competitive ability of yellow toadflax in peppermint.
DE: weed control\Linaria vulgaris\Mentha piperita\biological control\biological control agents\biomass\crop weed competition\competitive ability\control programmes\Cosmopterigidae\glyphosate\herbicides\host specificity\Lepidoptera\Scrophulariaceae\weeds\Eteobalea serratella\Cosmopterigidae
GL: USA\Wisconsin
AN: 0W04804525\0E08711955\7E02002402\0C07002595\5C00600626

TI: A study on determining pathogenic rust fungi on weeds in Van province.
AU: Özrenk, K.\ Tepe, I.
JN: Türkiye Herboloji Dergisi
YR: 1999
VL: 2
NO: 1
PP: 17-24
LA: En
LS: tr
MS: 35 ref.
AA: Yüzüncü Y University, Faculty of Agriculture, Department of Plant Protection, 65080, Van, Turkey.
AB: In studies conducted between March and November in 1996 and 1997, rust fungi were found on 57 weed species. A total of 43 species belonging to 4 pathogenic rust genera (1 species of Melampsora, 2 species of Phragmidium, 28 species of Puccinia and 12 species of Uromyces) was identified. Five of the species are first-time records for the Turkish parasitic microflora, and 15 weed species are new hosts for their pathogens for Turkey. The location and severity of infections were investigated and their importance to biological control was evaluated.
DE: rust diseases\weeds\biological control\weed control\hosts of plant diseases\Melampsora\plant pathogenic fungi\Phragmidium\Puccinia\Turkey\Uromyces\weeds\plant diseases\plant pathogens\plant pathogenic fungi
GL: Turkey
AN: 0W04803853\7E02002459

TI: Isolation of Fusarium oxysporum with potential for biocontrol of the witchweed (Striga hermonthica) in the Nigerian savanna.
AU: Marley, P. S.\ Ahmed, S. M.\ Shebayan, J. A. Y.\ Lagoke, S. T. O.
JN: Biocontrol Science and Technology
YR: 1999
VL: 9
NO: 2
PP: 159-163
LA: En
MS: 18 ref.
AA: Department of Crop Protection, Ahmadu Bello University, Samaru, P.M.B. 1044, Zaria, Nigeria.
AB: A fungus isolated from wilted Striga hermonthica plants was identified as Fusarium oxysporum. A comparison of this isolate (PSM-197) with four other Fusarium spp. for control of S. hermonthica using conidial foliar sprays showed that it was the most pathogenic and virulent. The isolate, grown on sorghum grain and incorporated into soil, completely inhibited the emergence of S. hermonthica compared with other substrates.
DE: Fusarium oxysporum\Nigeria\savannas\Striga\Striga hermonthica\weed control\plant pathogenic fungi\Sorghum\biological control\weeds\parasitic weeds\mycoherbicides\Sorghum bicolor\emergence\plant diseases\plant pathogens
GL: Nigeria
AN: 0W04804151\0Q05209040\7E02002512

TI: Impact of Smicronyx spp. (Coleoptera: Curculionidae) on fruit development of the parasitic weed Striga hermonthica (Scrophulariaceae): histological study and prospects for biological control.
AU: Pronier, I.\ Pare, J.\ Vincent, C.\ Salle, G.
JN: Acta Biologica Cracoviensia. Series Botanica
YR: 1998
VL: 40
PP: 9-13
LA: En
MS: 13 ref.
AA: Université de Picardie Jules Verne, Facultédes Sciences, 33 rue Saint-Leu, 80039 Amiens, France.
AB: The embryological development of Striga hermonthica was studied in capsules that were normal (unattacked) and attacked by Smicronyx weevils, and the findings are described. Following attack, 3 kinds of phenomena were observed: the induction of galls in the fruits, which become more voluminous, due to eggs being laid in the ovary; the formation of galls but no larval development; and the parasitization by larvae but without the fruits becoming galls. These findings should be of interest in implementing a Striga management programme based on seed bank control.
DE: biological control\Coleoptera\Curculionidae\parasitic weeds\Smicronyx\Striga\Striga hermonthica\weeds\Scrophulariaceae\seed predation\plant development\plant embryos\seed banks
AN: 0W04804150

TI: Biological control of salvinia.
AU: Wilson, C. G.
JN: Agnote (Darwin)
YR: 1999
NO: No. 547
PP: 3 pp.
LA: En
AB: A number of infestations of Salvinia molesta, a free-floating water fern, are present in the Northern Territory of Australia. The search for natural enemies of S. molesta from its centre of origin in Brazil is reviewed. The release of Samea multiplicalis in Queensland failed to impact upon S. molesta infestations. Cyrtobagous salviniae was released in 1980 on Lake Moondarra in Queensland and in 14 months had reduced an estimated 19 000 t of S. molesta to <1 t. C. salviniae has been released at many locations in Australia, providing excellent weed control. The life cycle and management of C. salviniae for the biological control of S. molesta are detailed. It is recommended that physical and chemical methods should be used on new S. molesta outbreaks, before resorting to biological control. C. salviniae will not be able to control S. molesta in some shallow, open sites where the water may be too hot for C. salviniae to breed.
DE: weed control\Salvinia molesta\aquatic weeds\biological control\biological control agents\natural enemies\Samea multiplicalis\Cyrtobagous salviniae
GL: Northern Territory\Queensland\Australia
AN: 0W04804175\7E02002510

TI: Biological-control herbivores may increase competitive ability of the noxious weed Centaurea maculosa.
AU: Callaway, R. M.\ DeLuca, T. H.\ Belliveau, W. M.
JN: Ecology
YR: 1999
VL: 80
NO: 4
PP: 1196-1201
LA: En
MS: 40 ref.
AA: Division of Biological Sciences, University of Montana, Missoula, Montana 59812, USA.
AB: The effectiveness of a widely used biological control moth, Agapeta zoegana, was tested for 2 years in the field in Montana, USA. A. zoegana had no significant direct effect on C. maculosa biomass. Instead of releasing a native grass from competition, the reproductive output of Festuca idahoensis planted with C. maculosa was significantly lower when neighbouring C. maculosa was attacked by A. zoegana. In a greenhouse experiment, F. idahoensis planted in pots with C. maculosa that had been attacked by Trichoplusia ni had significantly smaller root systems (root biomass = 0.33 g) than when planted with C. maculosa that were protected from herbivory (0.41 g). Root systems of C. maculosa that had been attacked by T. ni exuded higher levels of total sugars, but not total phenols. It is hypothesized that moderate herbivory stimulated compensatory growth, induced the production of defense chemicals that also had allelopathic effects, or stimulated root exudates that altered the relationship between C. maculosa and F. idahoensis via soil microbes. It is concluded that herbivory may increase the negative effects of C. maculosa on neighbouring plants, and that some biological control agents may have indirect negative effects on native species.
DE: Centaurea maculosa\biological control agents\biological control\weeds\Festuca idahoensis\phenols\sugars\Trichoplusia ni\Agapeta zoegana\Festuca idahoensis\reproduction\growth
GL: Montana\USA
AN: 0W04804066\0E08711967\7E02002495

TI: Field evaluation of a native fungus for control of melaleuca (Melaleuca quinquenervia) in southern Florida.
AU: Rayachhetry, M. B.\ Elliott, M. L.\ Center, T. D.\ Laroche, F.
JN: Weed Technology
YR: 1999
VL: 13
NO: 1
PP: 59-64
LA: En
MS: 36 ref.
AA: Fort Lauderdale Research and Education Center, University of Florida,
3205 College Avenue, Fort Lauderdale, FL 33314, USA.
AB: A native fungus of Florida, USA, Botryosphaeria ribis, was evaluated under field conditions to determine its potential to control M. quinquenervia. Applications consisted of either wound inoculations of trees with B. ribis or fresh stump treatments with B. ribis alone or mixed with imazapyr (Arsenal® at 12, 24, 60 and 120 mg/ml). There was no mortality among non-defoliated trees inoculated with B. ribis. The mortality of B. ribis-inoculated trees was increased by 3 complete defoliation cycles. Defoliated trees inoculated with isolate BR-5 exhibited 100% mortality compared to 17% for defoliated but non-inoculated trees. Wounds inoculated with B. ribis during winter produced longer cankers (31.2 cm) than non-inoculated wounds (9.2 cm). Stump regrowth reduction by B. ribis treatment alone (84% of stumps with regrowth, compared with 96% in the untreated control after 15 months) was less effective than treatment with imazapyr alone (<5% regrown). B. ribis + imazapyr or imazapyr alone at comparable concentrations did not differ in stump regrowth control.
DE: plant pathogenic fungi\biological control agents\biological control\weed control\weeds\Melaleuca quinquenervia\Botryosphaeria ribis\defoliation\herbicides\chemical control\imazapyr\integrated control\woody weeds\mycoherbicides\plant pathogens\plant diseases
GL: Florida\USA
AN: 0W04803713\0F06008510\7E02002494

TI: Assessing economic impacts of biological control of weeds: the case of leafy spurge in the northern Great Plains of the United States.
AU: Bangsund, D. A.\ Leistritz, F. L.\ Leitch, J. A.
JN: Journal of Environmental Management
YR: 1999
VL: 56
NO: 1
PP: 35-43
LA: En
MS: 22 ref.
AA: Department of Agricultural Economics, North Dakota State University, Fargo, ND 58105, USA.
AB: Estimations are made of the gross benefits of the biological control of Euphorbia esula on rangeland and wildland in Montana, North Dakota, South Dakota and Wyoming, USA. A bioeconomic model that related the biophysical impacts of controlling E. esula infestations to economic outcomes was used. The economic benefits on rangeland were based on predicted changes in grazing output, and benefits on wildland were based on predicted changes to wildlife habitat productivity and soil and water conservation. It is predicted that the acreage of E. esula will increase until about 2000, when the area infested will be 1.85 million acres in the northern Great Plains. It is estimated that 65% of future infested acreage will be controlled biologically by 2025. The direct impacts of biological control on rangeland and wildland were estimated at $16.45 million and $2.6 million, respectively. Secondary impacts, as estimated using an input-output model, were estimated at $39.3 million, resulting in a total annual economic impact of $58.4 million.
DE: weeds\biological control\weed control\Euphorbia esula\rangelands\range management\grasslands\economics\grazing\soil conservation\water conservation\models
GL: North Dakota\South Dakota\Wyoming\Montana\USA
AN: 0W04803638\7E02002491

TI: Eating habits and behaviour of Aigamo ducks in paddy field.
AU: Asano, H.\ Isobe, K.\ Tsuboki, Y.
JN: Journal of Weed Science and Technology
YR: 1999
VL: 44
NO: 1
PP: 1-8
LA: En
LS: ja
MS: 9 ref.
AA: Department of Agriculture, Junior Coll, Nihon University, Fujisawa 252-8510, Japan.
AB: In the Aigamo duck farming system, weeds of paddy fields are controlled using Aigamo ducks. The eating habits of this duck and actions related to their weed control ability were researched, and the effect of weeding using Aigamo ducks evaluated. A survey of the gullets of the ducks showed a tendency to eat insects as well as weeds. This meant that letting the ducks loose would achieve not only the effect of weeding, but also the extermination of harmful insects. Aigamo ducks were vigorously active early in the morning and at dusk, and moved around freely in the paddy fields. A follow-up survey on one individual duck found the distance covered was 3.8 km during the period from 03.00 h to 20.00 h (17 h) in a 56 m x 37 m paddy field. The period during which the ducks were let loose amounted to 40-50 days, from the end of June (3-4 weeks after transplanting of rice) to the beginning of August (heading date). Thus, it is concluded that the area covered during their active hours is adequate for weed control. Persicaria thunbergii, P. hydropiper and Scirpus juncoides remained following the Aigamo ducks cultivation, but the weed control they achieved was great and was almost the same as that achieved using herbicides. Weeds were controlled from a week after the ducks were let loose to the beginning of August.
DE: Scirpus juncoides\weeds\weed control\rice\Oryza sativa\cultural control\biological control\ducks\insect pests\Persicaria thunbergii\Persicaria hydropiper\ biological control agents
GL: Japan
AN: 0W04803626\7E02002151

TI: A biological agent for the control of starfruit comes closer.
CT: Rice special.
AU: Jahroini, F.\ Cother, E.\ Ash, G.
JN: Farmers' Newsletter, Large Area
YR: 1998
NO: No. 152
PP: 46-47
LA: En
AA: Charles Sturt University, Wagga, Australia.
AB: Current research into the development of Rhynchosporium alismatis as a mycoherbicide for the control of starfruit (Damasoniuni minus [Damasoni minus]) is outlined, including optimization of fungal growth and sporulation, optimization of infection and disease development in D. minus, synergism of chemical herbicides with the fungus and genetic variation of D. minus. Future research is proposed on the effects of the disease on weed competition.
DE: biological control\weeds\weed control\aquatic weeds\Damasonium minus\rhynchosporium alismatis\plant pathogenic fungi\biological control agents\growth\sporulation\mycoherbicides\herbicides\chemical control\integrated control\plant diseases\genetic variation\research\product development\Rhynchosporium\plant pathogens
AN: 0W04803743\0M07808935\7E02002508

TI: Effects of the plant-pathogenic fungus Mycocentrospora acerina (Hartig) Deighton on growth and competition of Viola arvensis (Murr.) in spring wheat.
AU: Lawrie, J.\ Greaves, M. P.\ Down, V. M.\ Lewis, J. M.
JN: Biocontrol Science and Technology
YR: 1999
VL: 9
NO: 1
PP: 105-112
LA: En
MS: 19 ref.
AA: IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol BS41 9AF, UK.
AB: M. acerina was found to kill or suppress the growth of V. arvensis in pot-grown spring wheat in both glasshouse and outdoor studies. The level of damage to V. arvensis and the effect on its competition with wheat were affected by inoculum density and environmental conditions. High inoculum density (10(5) macroconidia/ml) caused high mortality in V. arvensis and eliminated its competitive effect on wheat. At a lower density (10(4) macroconidia/ml), V. arvensis fresh weight and its competition with wheat were suppressed by up to 38 and 28%, respectively, depending on environmental conditions.
DE: plant pathogenic fungi\fungi\Mycocentrospora acerina\biological control agents\biological control\weeds\weed control\biological control\wheat\Triticum aestivum\Viola arvensis\crop weed< competition\growth\application rates\plant pathogens\plant diseases
AN: 0W04803283\6T01603515\0M07809068\7E02002490

TI: Biological control of plant invaders: regional patterns, field experiments, and structured population models.
CT: Community-level dynamics in pest management. A symposium held at the national meetings of the Entomological Society of America, 12 December 1996 [edited by Letourneau, D. K.; Andow, D. A.].
AU: McEvoy, P. B.\ Coombs, E. M.
JN: Ecological Applications
YR: 1999
VL: 9
NO: 2
PP: 387-401
LA: En
MS: 2 pp. of ref.
AA: Division of Entomology, Commonwealth Scientific and Industrial Research Organization, GPO Box 1700, Canberra, Australian Capital Territory 2601, Australia.
AB: New concepts and methods in the biological control of plant invaders combine herbivores and resource limitation of plant population growth, and use targeted life-cycle disruption, which involves identifying plant life-cycle transitions that are both amenable to manipulation and influential on population growth, and then targeting these for control. To illustrate these developments, an experimental and computational approach is outlined, which measures how the processes of disturbance, colonization and organism interactions (plant competition and herbivory) manifest their influence on weed life cycles and population growth of ragwort (Senecio jacobaea), a biennial or short-lived perennial herb. Manipulating these forces may lead to designs of biological control systems that are economic, potent and pose minimum risk to nontarget organisms.
DE: biological control\weeds\weed control\natural enemies\predators\population growth\resources\models\colonization\plant competition\Senecio jacobaea\conferences
AN: 0W04803700\7E02002489

TI: Host-plant affinities of two biotypes of Dactylopius opuntiae (Homoptera: Dactylopiidae): enhanced prospects for biological control of Opuntia stricta (Cactaceae) in South Africa.
AU: Volchansky, C. R.\ Hoffmann, J. H.\ Zimmermann, H. G.
JN: Journal of Applied Ecology
YR: 1999
VL: 36
NO: 1
PP: 85-91
LA: En
MS: 37 ref.
AA: Department of Zoology, University of Cape Town, Rondebosch 7701, South Africa.
AB: In an attempt to improve the biological control of O. stricta in South Africa, a stock of D. opuntiae was obtained from O. stricta in Australia during 1996. Host-specificity tests confirmed that the newly imported D. opuntiae from Australia is a different biotype to the one already established in South Africa. The Australian ('stricta') biotype thrived on O. stricta but was unable to develop satisfactorily on O. ficus-indica, while the converse was true for the South African ('ficus') biotype, which thrived on O. ficus-indica but fared poorly on O. stricta. The integrity of the host-plant specificity of the two biotypes of D. opuntiae has important implications for biological control of Cactaceae in South Africa, and has greatly enhanced prospects that O. stricta can be brought under biological control successfully.
DE: Opuntia stricta\weeds\weed control\biological control\Dactylopius opuntiae\biological control agents\natural enemies\Opuntia ficus-indica
GL: Australia\South Africa
AN: 0W04803278\0E08711964\7E02002488

TI: The potential for biological control of Scotch broom (Cytisus scoparius) (Fabaceae) and related weedy species.
AU: Syrett, P.\ Fowler, S. V.\ Coombs, E. M.\ Hosking, J. R.\ Markin, G.
P.\ Paynter, Q. E.\ Sheppard, A. W.
JN: Biocontrol News and Information
YR: 1999
VL: 20
NO: 1
PP: 17N-34N
LA: En
MS: 4 pp. of ref.
AA: Landcare Research, P.O. Box 69, Lincoln, Canterbury, New Zealand.
AB: Cytisus scoparius (Scotch broom) is an aggressive invader of agricultural, forestry, and conservation lands in many parts of its exotic range. Biological control programmes for Scotch broom with insects began in the USA in the 1950s, in New Zealand in 1981, and in Australia in 1990. Two insect species (Exapion fuscirostre and Leucoptera spartifoliella) have been intentionally introduced into the USA, two (Bruchidius villosus and Arytainilla spartiophila) into New Zealand and three (L. spartifoliella, B. villosus and A. spartiophila) into Australia. Also, nine broom-feeding species were accidentally introduced into North America, and one into New Zealand. Scotch broom remains a problem weed in all three regions, and other related brooms in the tribe Genisteae, also of European origin (C. striatus in North America, Genista monspessulana in North America and Australia, G. linifolia and G. stenopetala in Australia, and Spartium junceum in Australia and North America), now give cause for concern. In Europe, 243 phytophagous insects and mites are associated with Scotch broom, and from these, and species recorded from other brooms, further possible insect biological control agents have been identified. Insufficient host specificity, and the risk of damage to closely related nontarget plants, may limit the use of some oligophagous insect species. However, several host-specific insect and mite species have been identified that may contribute to managing Scotch broom throughout its exotic range. Pathogens have been identified that could be used as classical biological control agents, or developed into mycoherbicides. The development of insects, mites, and pathogens for control of broom species will contribute to the sustainable management of an important group of problem weeds.
DE: weeds\weed control\biological control\biological control agents\natural enemies\beneficial insects\Cytisus scoparius\Exapion fuscirostre\Leucoptera spartifoliella\Bruchidius villosus\Arytainilla spartiophila\Cytisus striatus\Genista monspessulana\Genista linifolia\Genista stenopetala\Spartium junceum\mites\Acari\beneficial arthropods\pathogens\mycoherbicides\Genista\Bruchidius\Leucoptera\ag ricultural land\agroforestry\reviews
GL: USA\Australia\New Zealand\North America
AN: 0W04802357\0E08707968\7E02002485

TI: Rapid evaluation of Fusarium spp. as a potential biocontrol agent for weeds.
AU: Pleban, S.\ Strobel, G. A.
JN: Weed Science
YR: 1998
VL: 46
NO: 6
PP: 703-706
LA: En
MS: 14 ref.
AA: Department of Plant Sciences, Montana State University, Bozeman, MT 59717, USA.
AB: A method is described for accurately evaluating the relative effectiveness of F. avenaceum isolates as potential biological control agents for weeds such as spotted knapweed (Centaurea maculosa) and wild oat (Avena fatua). Seeds were disinfected, placed in tubes containing water agar, potato dextrose agar, or Schizophyllum minimal medium and challenged with various F. avenaceum isolates. Evaluatory data on the pathogenicity of the fungi were obtained after 14 days in the laboratory. The type of media on which seeds were tested was found to affect germination rates. Comparisons were made between a standard method using seeds placed in soil and the water agar test. The tests were compared using several plant species, including wheat, barley, alfalfa, and wild oat. The results indicated that the water agar test gave comparable results to the greenhouse tests, but after 14 days, as opposed to 60 days. F. avenaceum isolates were identified that significantly decreased spotted knapweed germination but did not affect wheat, barley, alfalfa and wild oat. This method is concluded to have the potential to screen many pathogens with potential biological control activities in a short time.
DE: weeds\weed control\biological control\biological control agents\beneficial organisms\Centaurea maculosa\Avena< fatua\Schizophyllum\wheat\Triticum aestivum\barley\Hordeum vulgare\lucerne\Medicago sativa\screening\culture media\pathogenicity\seed germination\methodology\Gibberella avenacea\plant pathogenic fungi
AN: 0W04802431\6T01602095\7G02202277\0M07809067\7E02002501

TI: Biological control of water hyacinth under conditions of maintenance management: can herbicides and insects be integrated?
AU: Center, T. D.\ Dray, F. A., Jr.\ Jubinsky, G. P.\ Grodowitz, M. J.
JN: Environmental Management
YR: 1999
VL: 23
NO: 2
PP: 241-256
LA: En
MS: 39 ref.
AA: US Department of Agriculture, Agricultural Research Service, Aquatic Plant Control Research, 3205 College Ave, Fort Lauderdale, Florida 33314, USA.
AB: It is hypothesized that repeated herbicidal (maintenance) control of water hyacinth (Eichhornia crassipes) infestations in Florida suppresses biological control agent populations, especially the weevils Neochetina eichhorniae and N. bruchi. In order to study this, water hyacinth and weevil populations were sampled at 54 sites distributed state-wide. Half were under maintenance control, and the other half were not treated with herbicides. General site conditions were assessed, demographic data were collected on weevil and plant populations, the reproductive condition of the weevils was determined, and plant nutrient and proximate composition of water hyacinth leaves were analysed. Water hyacinth infestations under maintenance control were minimal when compared to unmanaged sites. Likewise, on a population basis, all weevil cohorts were much lower due to the paucity of plants. Plants at unmanaged sites, where weevil intensities were much higher, suffered high levels of stress and showed low growth potential. Lower percentages of the female weevils were reproductive at unmanaged sites when compared to managed sites, so densities of reproductives and immatures were similar at both site types. Reproductive status of the weevils improved with increased plant quality. Plant quality, in turn, declined as stresses arising from weevil feeding increased. Plant quality was positively correlated with plant growth potential and flower production. Thus, maintenance control improved plant nutritive quality thereby inducing reproductive vigour of the weevils, but ensuring plant regrowth and the need for future control. This suggests that biological and herbicidal controls should be integrated, using herbicides to maintain water hyacinth infestations below management thresholds but in a manner that conserves biological control agent populations. This approach would lead to improved plant nutritional quality that would, in turn, stimulate reproduction in biological control agent populations.
DE: biological control\aquatic weeds\Eichhornia crassipes\herbicides\integrated control\Neochetina eichhorniae\Neochetina bruchi\population dynamics\reproduction\nutrient content\growth\biological control agents
GL: USA\Florida
AN: 0W04802075\0E08707960\7E02002505

TI: Future strategies for effective parthenium management.
CT: First international conference on Parthenium management, Dharwad, India, 6-8 October 1997.
AU: Bhan, V. M.\ Sushilkumar\ Raghuwanshi, M. S.
YR: 1997
PP: 90-95
LA: En
MS: 28 ref.
AA: National Research Centre for Weed Science, Adhartal, Jabalpur - 482 004, Madhya Pradesh, India.
AB: Research into the biological control of parthenium (Parthenium hysterophorus) in India is reviewed. Zygogramma bicolorata was imported from Mexico and partly suppressed parthenium. However, Z. bicolorata was observed feeding on sunflowers and Xanthium strumarium and concerns exist that Z. bicolorata may become a pest of sunflowers. Studies to confirm the potential of Z. bicolorata as a pest on sunflowers are ongoing. Previous manual, legal and chemical management practices have achieved limited success. Based on< evaluations of previously utilized control methods, an integrated control system is proposed. Future research areas for effective parthenium management are suggested.
DE: Parthenium hysterophorus\sunflowers\Helianthus annuus\weeds\Xanthium strumarium\Zygogramma bicolorata\Zygogramma\weed control\integrated pest management\biological control\chemical control\cultural control\regulations\conferences
GL: India
AN: 0W04802044

TI: Trichoderma virens -inoculated composted chicken manure for biological weed control.
AU: Hutchinson, C. M.
JN: Biological Control
YR: 1999
VL: 16
NO: 2
PP: 217-222
LA: En
MS: 10 ref.
AA: Department of Botany and Plant Sciences, University of California, Riverside, California 92521, USA.
AB: Laboratory and greenhouse experiments were conducted to investigate the conditions necessary for the production and stabilization of the Gliocladium virens phytotoxin viridiol, its mycoherbicidal properties, and to develop a system for the production of viridiol on a composted chicken manure substrate. Results indicated that the phytotoxicity of viridiol is enhanced at acidic pH. The EC(50)s of viridiol for inhibition of seed germination and root growth were 312 and 56.3 ¼M, respectively, in Setaria viridis and 764 and 1.3 ¼M, respectively, in Amaranthus retroflexus. A composted chicken manure substrate supplemented with nutrients was developed that supported T. virens growth and viridiol production of <170 ¼g/g. In laboratory trials, it produced viridiol 10 days after being incorporated into soil. The results of greenhouse trials indicated that it reduced weed emergence and dry weight by 77% and 68%, respectively, 8 weeks post-incorporation.
DE: weeds\weed control\biological control\biological control agents\manures\mycoherbicides\Setaria viridis\Amaranthus retroflexus\Trichoderma\Gliocladium virens
AN: 0W04901044

TI: The use of long term transects to assess the impacts of weed control.
CT: People and rangelands: building the future. Proceedings of the VI International Rangeland Congress, Townsville, Queensland, Australia, 19-23 July, 1999. Volumes 1 and 2 [edited by Eldridge, D.; Freudenberger, D.].
AU: Lindsay, A.\ Dorney, W.\ Gray, E.\ Setter, C.
YR: 1999
PP: 605-607
BN: ISBN 0-9577394-0-0 (set)
LA: En
MS: 8 ref.
AA: Charters Towers, QLD 4820, Australia.
AB: The measurements of two people monitoring the impacts of the biological control agent, Maravalia cryptostegia on Cryptostegia grandiflora were compared in Queensland, Australia. Two scorers assessed the same transect on the same day, measuring bulk and whip height of C. grandiflorafoliar and projective canopy cover of plants above 1 m in height C. grandiflora defoliation and grass foliar cover. The variables measured most consistently were canopy and whip height. However, the results indicate that, even where scorers can train their successors, it is difficult to maintain consistency in the assessment of field measurements. Greatest difficulty in achieving consistency will be encountered where a variable is difficult to define precisely, or where a subjective assessment is required.
DE: conferences\Maravalia cryptostegiae\biological control\Cryptostegia grandiflora\weeds\weed control\monitoring\Asclepiadaceae\methodology\Uredinales\rust diseases\plant pathogenic fungi\plant pathogens\plant diseases\rangelands
GL: Queensland\Australia
AN: 0W04900571

TI: Current research on environmental weeds.
CT: Environmental weed forum, Heidelberg, Victoria, Australia, 19-21 July 1999.
AU: Ainsworth, N.
JN: Plant Protection Quarterly
YR: 1999
VL: 14
NO: 3
PP: 108-111
LA: En
MS: 9 ref.
AA: Keith Turnbull Research Institute and CRC for Weed Management Systems, PO Box 48, Frankston, Victoria 3199, Australia.
AB: A summary of current environmental weeds research projects at the Cooperative Research Centre for Weed Management Systems in Victoria, Australia, is given. Research into the biological control of Asparagus asparagoides, Chrysanthemoides monilifera subsp. monilifera and rotundata, Cytisus scoparius,Rubus fruticosus, Marrubium vulgare, Hypericum perforatum, gorse [Ulex europaeus] and serrated tussock [Nassella trichotoma] is reviewed. The use of mycoherbicides and herbicides as weed control agents, nontarget effects of herbicides, and integrated control approaches, are also discussed.
DE: weeds\weed control\reviews\conferences\biological control\Asparagus asparagoides\Asparagus\Chrysanthemoides monilifera\Chrysanthemoides\Cytisus scoparius\Rubus fruticosus\blackberries\crop plants as weeds\Marrubium vulgare\Hypericum perforatum\Ulex europaeus\Nassella trichotoma\mycoherbicides\herbicides\nontarget effects\integrated control\plant pathogenic fungi
GL: Victoria\Australia
AN: 0W04900567

TI: Infection process and resistance in the weed pathosystem Senecio vulgaris - Puccinia lagenophorae and implications for biological control.
AU: Wyss, G. S.\ Müller-Schärer, H.
JN: Canadian Journal of Botany
YR: 1999
VL: 77
NO: 3
PP: 361-369
LA: En
LS: fr
MS: 2 pp. of ref.
AA: Swiss Federal Research Station of Fruit-Growing, Viticulture and Horticulture, CH-8820 Wädenswil, Switzerland.
AB: The infection process and the level and type of resistance in the pathosystem of a native weed and a naturalized rust fungus, Senecio vulgaris-Puccinia lagenophorae, were examined. Four inbred plant lines from Switzerland (2), Netherlands, and the UK, each at two stages of development, were exposed to corresponding rust lines under controlled conditions. Fluorescence and light microscopy were used to assess the infection process and to quantify genotype effects. Component analysis was used to partition disease development and define the infection process. Germinating aeciospores of P. lagenophorae showed all the characteristics of the monokaryotic parasitic stage of rust infection with direct penetration and monokaryotic haustoria formation. Haustoria formed between 3 and 6 days after inoculation at low frequency. The highest level of resistance, for which differences between plant lines were detected, occurred at penetration peg formation. All the studied host-pathogen interactions were compatible. The Dutch plant line was most susceptible to all rust lines, and the Dutch rust line was the most aggressive. Susceptibility of leaves increased with the leaf development stage. There was a continuous range of variation in susceptibility without differential genetic interactions, thus indicating race-nonspecific quantitative resistance. The use of the more aggressive Dutch rust line may increase the level of disease, thus stimulating epidemics for biological control. Over the long term, less susceptible genotypes of the weed may be selected, although differences in susceptibility among plant lines were relatively small.
DE: biological control\biological control agents\Puccinia lagenophorae\Senecio vulgaris\weeds\fungi\genotypes\haustoria\infection\inoculation\rust diseases\susceptibility\plant diseases\plant pathogens\Puccinia
AN: 0W04900572