Over 35 years, integrated pest management has reduced pest risks and pesticide use

Pests and their interactions with crops, ecological landscapes and animals are in continuous flux — they are never static. Pest severity increases or decreases depending on environmental conditions and changes in production or pest control practices. Pest management is made even more challenging by exotic and newly invasive pests. Over its 35-year history, the UC Agriculture and Natural Resources Statewide IPM Program has supported research and extension that has decreased risks of crop losses, improved treatment programs for invasive and endemic pests, and reduced the use of pesticides and their impact on the environment and human health. Its publications are widely used among growers, pest control advisers, research institutions, state agencies, agricultural organizations and gardeners; and integrated pest management has been adopted statewide in agriculture, as well as in managed landscapes and urban areas.

Relative impact of spider predation and cover crop on population dynamics of Erythroneura variabilis in a raisin grape vineyard

Experimental and correlative evidence has steadily mounted over the past 30 years implicating spiders in the suppression of insect herbivore pests in crop fields. A large body of evidence has also shown that increasing agroecosystem vegetation diversity often influences the abundance of herbivores and their natural enemies. In previous experiments, the abundance of several species of spiders on grapevines in a raisin grape vineyard was twofold enhanced in vineyard plots vegetationally diversified with a cover crop. A concomitant reduction in the abundance of the leafhopper pest Erythroneura variabilis Beamer was observed on grapevines in the diversified plots, but a causal relationship was not established. In the present study, we simultaneously manipulated spider densities (in open-vine spider exclusion and vine-shoot enclosures) and ground cover to determine their relative impact on E. variabilis population dynamics. Open-vine spider exclusion resulted in an average 35% increase in the density of E. variabilis the greatest effect with occurring during the first and second leafhopper generations. The negative impact of spiders on E. variabilis densities was corroborated with vine-shoot enclosure experiments. Under the conditions of the present study, the cover crop per se did not affect the dynamics of E. variabilis populations on grapevines, despite a 1.6-fold increase in spider densities on vines in cover crop plots, compared with vines in bare ground plots, probably due to insufficient spider enhancement and low overall E. variabilis abundance during the summer months. The cover crop had little effect on vine macronutrient status (and presumably vine water status). While this study provided further support for the hypothesis that vegetation diversity can enhance spider abundance, this enhancement does not always lead to lower pest densities, thus underscoring the complexity and variability that exists in interactions involving cover crop, spiders, and crop plants and their herbivore pests

Effects of agricultural management on nematode-mite assemblages Soil food web indices as predictors of mite community composition

Biological indicators based on abundances of soil organisms are powerful tools for inferring functional and diversity changes in soils affected by agricultural perturbations. Field plots, combining organic and conventional practices with no tillage, conservation tillage and standard tillage maintained different nematode assemblages and soil food webs. Soil food web indices based on nematode assemblages were reliable predictors of the trophic composition of functional characteristics of soil mite assemblages. Bacterial-feeding and predatory nematodes, together with predatory mites, were abundant in the organic-no till treatments and were associated with high values of the Enrichment and the Structure Index based on nematode assemblages. Conventional-Standard tillage treatments had high abundances of fungal- and plant-feeding nematodes and algivorous mites, associated with high values of the Basal and Channel Index. This study validates the hypothesis that nematode-based soil food web indices are useful indicators of other soil organisms such as mites, with similar functional roles and environmental sensitivities. © 2008 Elsevier B.V. All rights reserved

Analysis of olive fly invasion in California based on microsatellite markers

The olive fruit fly, Bactrocera oleae, is the main pest of the olive fruit and its expansion is exclusively restricted to the cultivation zone of the olive tree. Even though olive production has a century-old history in California, the olive fly was first detected in the Los Angeles area in 1998. Within 5 years of the first observation, the insect was reported from all olive cultivation areas of the state. Field-collected flies from five locations in California and another from Israel were analyzed on the basis of microsatellite polymorphisms in 10 microsatellite loci. These results were integrated with those of a previous study of olive fly populations around the European part of the Mediterranean basin. The analysis pointed to the eastern part of the Mediterranean as the putative source of the observed invasion. Moreover, samples from California were quite different from Mediterranean samples implying the participation of phenomena such as genetic drift during the invasion and expansion of the olive fly in California

Over 35 years, integrated pest management has reduced pest risks and pesticide use

Pests and their interactions with crops, ecological landscapes and animals are in continuous flux — they are never static. Pest severity increases or decreases depending on environmental conditions and changes in production or pest control practices. Pest management is made even more challenging by exotic and newly invasive pests. Over its 35-year history, the UC Agriculture and Natural Resources Statewide IPM Program has supported research and extension that has decreased risks of crop losses, improved treatment programs for invasive and endemic pests, and reduced the use of pesticides and their impact on the environment and human health. Its publications are widely used among growers, pest control advisers, research institutions, state agencies, agricultural organizations and gardeners; and integrated pest management has been adopted statewide in agriculture, as well as in managed landscapes and urban areas.

Over 35 years, integrated pest management has reduced pest risks and pesticide use

Pests and their interactions with crops, ecological landscapes and animals are in continuous flux — they are never static. Pest severity increases or decreases depending on environmental conditions and changes in production or pest control practices. Pest management is made even more challenging by exotic and newly invasive pests. Over its 35-year history, the UC Agriculture and Natural Resources Statewide IPM Program has supported research and extension that has decreased risks of crop losses, improved treatment programs for invasive and endemic pests, and reduced the use of pesticides and their impact on the environment and human health. Its publications are widely used among growers, pest control advisers, research institutions, state agencies, agricultural organizations and gardeners; and integrated pest management has been adopted statewide in agriculture, as well as in managed landscapes and urban areas.