scholarly journals Biological Control of the Weedy Plant (Rumex crispus) at the Seedling Growth Stage by the Green Dock Beetle (Gastrophysa viridula)

2019 ◽  
Vol 28 (1) ◽  
pp. 21-31
Author(s):  
Khalid S. Alshallash Khalid S. Alshallash
Keyword(s):  
Biological Control ◽  
Seedling Growth ◽  
Growth Stage ◽  
Biological Control Agent ◽  
Dry Weight ◽  
Control Agent ◽  
Growth Stages ◽  
Rumex Crispus ◽  
Shoot Number ◽  
The Impact

In four glasshouse experiments, the effectiveness of the adult green dock beetle Gastrophysa viridula (Coleoptera: Chrysomelidae), at the effective number of applied individuals, for use as a biological control agent of curled dock, Rumex crispus (Polygonaceae) were studied. The feeding of the beetle was investigated at four different numbers of beetle (0, 1, 2, 3) and at four seedling growth stages of the plant, defined by the average of leaf area per plant (1-1.22 , 2-4.45, 3-11.56, and 4-71.52 cm2/plant). Grazing by one, two or three dock beetles did not result in a significant reduction in dock dry weight or shoot numbers at the youngest growth stage. However, both at later seedling growth stages were significantly affected (P ? 0.0001), at any beetles number. The increase of beetle numbers caused nonsignificant increased effect, in some trials, confirming the impact of a single beetle. Three months after beetle grazing, dock seedlings of first, second and third growth stages were not able to regrow, however, some plants at the 4th growth stage, re-emerged. This suggested that the highest effect of beetle's feeding occurs on the early seedling stages. Statistical analysis showed a positive correlation (0.77) between dry weight and shoot number at all the four seedling growth stages, thus confirming the impact of the beetle on both the dry weight and shoot numbers. Combining beetle grazing with other control methods at older dock seedling stages could, therefore, provide better suppression

scholarly journals Impact Assessment of Biological Control-Based Integrated Pest Management in Rice and Maize in the Greater Mekong Subregion

Insects ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 226 ◽  
Author(s):  
Dirk Babendreier ◽  
Min Wan ◽  
Rui Tang ◽  
Rui Gu ◽  
Justice Tambo ◽  
...  
Keyword(s):  
Biological Control ◽  
Integrated Pest Management ◽  
Pest Management ◽  
Smallholder Farmers ◽  
Biological Control Agent ◽  
Control Agent ◽  
Target Area ◽  
Positive Effects ◽  
The Difference ◽  
The Impact

The impact and sustainability of two interventions that have been formulated to introduce integrated pest management (IPM) into rice and maize crops in Southwestern China, Laos, and Myanmar between 2011 and 2016, and were assessed at the end of 2017. From 22 Trichogramma rearing facilities established during the interventions, 11 were still producing substantial quantities of biocontrol agents 1.5 years after project support had ended, while seven had stopped operations completely, and four were doing stock rearing only. Through the implementation of biological control-based IPM, slightly higher yields were achieved in maize and rice (4–10%), when compared to control farmers, but the difference was not statistically significant. However, the use of pesticides nearly halved when farmers started using Trichogramma egg-cards as a biological control agent. Support from either public or private institutions was found to be important for ensuring the sustainability of Trichogramma rearing facilities. Many of the suggested IPM measures were not adopted by smallholder farmers, indicating that the positive impacts of the interventions mostly resulted from the application of Trichogramma biological control agents. The following assessment suggests that further promotion of IPM adoption among farmers is needed to upscale the already positive effects of interventions that facilitate reductions in synthetic pesticide use, and the effects on sustainable agricultural production of rice and maize in the target area more generally.

scholarly journals Biological Diabrotica Management and Monitoring of Metarhizium Diversity in Austrian Maize Fields Following Mass Application of the Entomopathogen Metarhiziumbrunneum

2021 ◽  
Vol 11 (20) ◽  
pp. 9445
Author(s):  
Maria Zottele ◽  
Johanna Mayerhofer ◽  
Hannah Embleton ◽  
Katharina Wechselberger ◽  
Jürg Enkerli ◽  
...  
Keyword(s):  
Biological Control ◽  
Population Structure ◽  
Biological Control Agent ◽  
Background Level ◽  
Dry Weight ◽  
Field Trials ◽  
Control Agent ◽  
Indigenous Populations ◽  
Colony Forming Units ◽  
Cultivation Techniques

Inundative mass application of Metarhizium brunneum BIPESCO 5 (Hypocreales, Clavicipitaceae) is used for the biological control of Diabrotica v. virgifera (Coleoptera, Chrysomelidae). Long-term field trials were performed in three Austrian maize fields—with different cultivation techniques and infestation rates—in order to evaluate the efficacy of the treatment to control the pest larvae. In addition, the indigenous Metarhizium spp. population structure was assessed to compare the different field sites with BIPESCO 5 mass application. Annual application of the product Granmet-PTM (Metarhizium colonized barley kernels) significantly increased the density of Metarhizium spp. in the treated soil above the upper natural background level of 1000 colony forming units per gram dry weight soil. Although a decrease in the pest population over time was not achieved in heavily infested areas, less damage occurred in treated field sites in comparison to control sites. The Metarhizium population structure was significantly different between the treated field sites. Results showed that inundative mass application should be repeated regularly to achieve good persistence of the biological control agent, and indicated that despite intensive applications, indigenous populations of Metarhizium spp. can coexist in these habitats. To date, crop rotation remains the method of choice for pest reduction in Europe, however continuous and preventive application of M. brunneum may also present an alternative for the successful biological control of Diabrotica.

scholarly journals A Conceptual Model to Describe the Decline of European Blackberry (Rubus anglocandicans), A Weed of National Significance in Australia

Plant Disease ◽  
2014 ◽  
Vol 98 (5) ◽  
pp. 580-589 ◽  
Author(s):  
S. Aghighi ◽  
L. Fontanini ◽  
P. B. Yeoh ◽  
G. E. St. J. Hardy ◽  
T. I. Burgess ◽  
...  
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
Control Program ◽  
Global Scale ◽  
Control Agent ◽  
Cultural Control ◽  
Potential Threat ◽  
Plant Populations ◽  
National Significance ◽  
The Impact

Human activities have had an adverse impact on ecosystems on a global scale and have caused an unprecedented redispersal of organisms, with both plants and pathogens moving from their regions of origin to other parts of the world. Invasive plants are a potential threat to ecosystems globally, and their management costs tens of billions of dollars per annum. Rubus anglocandicans (European blackberry) is a serious invasive species in Australia. Herbicide and cultural control methods are generally inefficient or require multiple applications. Therefore, a biological control program using stem and leaf rust strains is the main option in Australia. However, biological control using rusts has been patchy, as host factors, climate, and weather can alter the impact of the rust at different locations. In 2007, Yeoh and Fontanini noticed that blackberry plants on the banks of the Donnelly and Warren rivers in the southwest of Western Australia were dying in areas that were being regularly monitored for the impact of rust as a biological control agent. The symptoms on blackberry became known as the disease “blackberry decline”. Continuous and intensive investigations are required to discover the different biotic and abiotic components associated with specific declines in plant populations. The only agent so far introduced to Australia for the biological control of blackberry is the rust Phragmidium violaceum.

Population dynamics and foraging behaviour of Diaeretus leucopterus (Hymenoptera: Braconidae), and its potential for the biological control of pine damaging Eulachnus spp. (Homoptera: Aphididae)

1996 ◽  
Vol 86 (4) ◽  
pp. 397-405 ◽  
Author(s):  
S.T. Murphy ◽  
W. Völkl
Keyword(s):  
Biological Control ◽  
Foraging Behaviour ◽  
Biological Control Agent ◽  
Host Density ◽  
Scientific Basis ◽  
Control Agent ◽  
Foraging Activity ◽  
Parasitism Rates ◽  
The Mean ◽  
The Impact

AbstractThe Palaearctic pine aphids, Eulachnus agilis (Kaltenbach) and Eulachnus rileyi (Williams) have both been introduced into other continents where they have been reported causing damage to economically important pines. In Euorpe, they are attacked by the specialist parasitoid Diaeretus leucopterus (Haliday) which has been suggested as a possible biological control agent. Here we report on several aspects of the ecology of the parasitoid, conducted on E. agilis in Germany in 1993–94, to provide a more scientific basis for judging its potential for use in biological control. Parasitism of all instars in the field rarely exceeded 10% and was independent of host density. A high percentage of parasitized aphids were hyperparasitized. Measurements of the impact over 16 weeks in a greenhouse-release experiment showed that parasitism rates increased from 2 to 19% but were insufficient to suppress the aphid population below a damaging level. There was evidence of a density-dependent response. Studies on foraging behaviour showed that female parasitoids searched pines by quite extensive walks. There was no relationship between the number of aphids per tree and number of ovipositions, and the mean number of ovipositions per female per tree was 2.5 ± 0.4 eggs. The majority (55.1%) of encountered aphids did not respond to the parasitoids. However, female parasitoids attacked a much higher proportion of aphids that did respond but oviposition success on this group was poor. The number of aphid-infested needles on seedlings increased significantly owing to the parasitoid's foraging activity. On the basis of these results, it is suggested that D. leucopterus is only likely to be of benefit in biological control if used in conjunction with other complementary natural enemies.

Impact ofCeutorhynchus liturafeeding on root carbohydrate levels in Canada thistle (Cirsium arvense)

Weed Science ◽  
2004 ◽  
Vol 52 (4) ◽  
pp. 628-633 ◽  
Author(s):  
Gary L. Hein ◽  
Robert G. Wilson
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
The United States ◽  
Control Agent ◽  
Larval Feeding ◽  
Canada Thistle ◽  
Free Sugars ◽  
Perennial Weed ◽  
Carbohydrate Levels ◽  
The Impact

Canada thistle is a serious perennial weed found throughout the northern regions of the United States and Canada. The weevil,Ceutorhynchus litura(F.), was first released in Canada in 1965 as a potential biological control agent for Canada thistle; however, its impact as a control agent has been sporadic. The objective of this study was to characterizeC. lituraimpacts on the carbohydrate profile in Canada thistle roots through the growing season and to evaluate the potential for this biological control agent in causing stress to Canada thistle. Field plots, infested withC. litura, were established and extensively sampled forC. liturainfestations. By samplingC. litura–damaged and undamaged Canada thistle shoots–roots through the season, we were able to establish the profile of free sugars and fructans in the roots and compare these levels to the presence and extent of insect damage. Levels of all free sugars and fructans were consistently found to be depressed in roots fromC. litura–damaged shoots early in the summer during and shortly after the larval feeding period.Ceutorhynchus liturafeeding in Canada thistle shoots appears to disrupt the movement of photoassimilates from leaves to roots. Late-season levels of free sugars and fructans indicate that roots do recover from these depressed levels, and in several instances, significant overcompensation occurred in the damaged roots. Measurement of free sugars and fructans to identify sublethal impacts of control tactics may allow the strategic combining of complementary tactics to maximize the impact of stresses on Canada thistle.

Effects of Mowing or SprayingCarduus thoermerionRhinocyllus conicus

1991 ◽  
Vol 5 (3) ◽  
pp. 628-631 ◽  
Author(s):  
Philip W. Tipping
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
Control Agent ◽  
Growth Stages ◽  
Full Bloom ◽  
Rhinocyllus Conicus

In 1988, mowing C.thoermerionce at the bud stage, twice at the bud stage, or once at early bloom of the primary inflorescences, eliminated emergence ofRhinocyllus conicus, a weevil introduced as a biological control agent. Mowing at full bloom reduced weevil survival by 78.8%, whereas mowing at senescence had no effect. In 1989, mowing at full bloom or senescence did not affect weevil survival. Dicamba applied at the full bloom or senescence stage did not affectR. conicussurvival, whereas hexazinone reducedR. conicussurvival when applied at all growth stages.

scholarly journals Influence of the Rearing Host on Biological Parameters of Trichopria drosophilae, a Potential Biological Control Agent of Drosophila suzukii

Insects ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 183 ◽  
Author(s):  
Svetlana Boycheva Woltering ◽  
Jörg Romeis ◽  
Jana Collatz
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
Control Agent ◽  
Invasive Pest ◽  
Drosophila Suzukii ◽  
Female Ratio ◽  
Host Switch ◽  
And Performance ◽  
Different Strains ◽  
The Impact

Trichopria drosophilae is a pupal parasitoid that can develop in a large number of drosophilid host species including the invasive pest Drosophila suzukii, and is considered a biological control agent. We investigated the influence of the rearing host on the preference and performance of the parasitoid, using two different strains of T. drosophilae, reared on D. melanogaster or D. suzukii for approximately 30 generations. Host switching was employed to assess the impact of host adaptation on T. drosophilae performance. In a no-choice experimental setup, T. drosophilae produced more and larger offspring on the D. suzukii host. When given a choice, T. drosophilae showed a preference towards D. suzukii, and an increased female ratio on this host compared to D. melanogaster and D. immigrans. The preference was independent from the rearing host and was confirmed in behavioral assays. However, the preference towards D. suzukii increased further after a host switch from D. melanogaster to D. suzukii in just one generation. Our data indicate that rearing T. drosophilae for several years on D. melanogaster does not compromise its performance on D. suzukii in the laboratory. However, producing a final generation on D. suzukii prior to release could increase its efficacy towards the pest.

scholarly journals Bacillus velezensis WZ-37, a New Broad-Spectrum Biocontrol Strain, Promotes the Growth of Tomato Seedlings

Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 581
Author(s):  
Xiuling Chen ◽  
Haifeng Huang ◽  
Shumei Zhang ◽  
Yao Zhang ◽  
Jingbin Jiang ◽  
...  
Keyword(s):  
Biological Control ◽  
Broad Spectrum ◽  
Biological Control Agent ◽  
Storage Period ◽  
Dry Weight ◽  
Gray Mold ◽  
Control Agent ◽  
Soluble Solids ◽  
Bacillus Velezensis ◽  
Tomato Seedlings

A biological control agent is arguably an ideal alternative to chemical fungicide for the prevention and control of gray mold disease. During this process, a biological control produces low levels of pollution, generates few residues that pose no risk to the environment, and pathogens cannot gain resistance to it easily. A new antifungal strain isolated from plant rhizosphere exhibited high antifungal activity against the phytopathogens Botrytis cinerea, Fusarium oxysporum f. sp. cucumerinum, F. moniliforme, Sclerotinia sclerotiorum, Colletotrichum orbiculare, Alternaria nees, F. equiseti, and F. oxysporum f. sp. lycopersici. It was identified as Bacillus velezensis WZ-37 by morphological and physiological indices and comparisons of 16S rRNA and gyrB genes. WZ-37 can significantly inhibit the mycelia growth of B. cinerea by 96.97%. It can reduce a tomato fruit’s decay rate after 21 days of storage by 33.33% (13.34% less for the control) without significantly affecting its firmness and soluble solids. Plant height, stem diameter, and the fresh and dry weight of tomato seedlings were significantly increased when their seeds were soaked in a WZ-37 suspension (106 cfu/mL) for 3 h and grown for 21 days in soil. WZ-37 has broad-spectrum biocontrol and can prolong a tomato’s storage period and enhance its seedlings’ growth, making it a promising candidate strain for broad-spectrum biocontrol applications in agriculture.

Biological control of the larger grain borer Prostephanus truncatus (Coleoptera: Bostrichidae) in Kenya using a predatory beetle Teretrius nigrescens(Coleoptera: Histeridae)

2003 ◽  
Vol 93 (4) ◽  
pp. 299-306 ◽  
Author(s):  
M.G. Hill ◽  
F.L.O. Nang'ayo ◽  
D.J. Wright
Keyword(s):  
Biological Control ◽  
Biological Control Agent ◽  
Pheromone Trap ◽  
Control Agent ◽  
Prostephanus Truncatus ◽  
Larger Grain Borer ◽  
Before And After ◽  
Short Rains ◽  
Trap Catches ◽  
The Impact

AbstractThe establishment of the predatory histerid beetle, Teretrius nigrescens Lewis, following its field release in south eastern Kenya in 1992, and its impact on populations of the larger grain borer, Prostephanus truncatus (Horn), in woodland habitats is evaluated. Pheromone trap catch data show a single strong peak of P. truncatus from November to January, coincident with the short rains. Comparisons of P. truncatus pheromone trap catches before and after predator establishment, and in areas with and without T. nigrescens, show a sustained decline of over 80% in P. truncatus abundance over a 5-year period, following the establishment T. nigrescens. Concurrent laboratory studies of the impact of T. nigrescens on populations of P. truncatus raised on a wood substrate showed a 77% reduction in the growth of the pest population. These results are compared with published findings of the impact of T. nigrescens as a biological control agent of P. truncatus in west Africa.

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