The digestive waste product of sucking herbivores, known as honeydew, betrays the presence of brown planthopper to rice plants, due to the bacteria contained in the honeydew secretions.

A population survey of phytoseiid mites and spider mites was conducted on peach leaves and wild plants in Japanese peach orchards having different pesticide practices. The phytoseiid mite species composition on peach leaves and wild plants, as estimated using quantitative sequencing, changed during the survey period. Moreover, it varied among study sites. The phytoseiid mite species compositions were similar between peach leaves and some wild plants, such as Veronica persica, Paederia foetida, Persicaria longiseta, and Oxalis corniculata with larger quantities of phytoseiid mites, especially after mid-summer. A PCR-based method to detect the ribosomal ITS sequences of Tetranychus kanzawai and Panonychus mori from phytoseiid mites was developed. Results showed that Euseius sojaensis (specialized pollen feeder/generalist predator) uses both spider mites as prey in the field.

Success of plants largely depends on their ability to defend against herbivores. Since emergence of the first voracious consumers, plants maintained adapting their structures and chemistry to escape from extinction. The constant pressure was further accelerated by adaptation of herbivores to plant defenses, which all together sparked the rise of a chemical empire comprised of thousands of specialized metabolites currently found in plants.

BACKGROUNDBemisia tabaci is a notorious agricultural pest that causes serious damage to many crops via herbivory and spread of viral diseases. Effective control measures are, therefore, required. Integrating entomopathogenic fungi into the chemical control system offers promise for B. tabaci management.RESULTSIn‐vitro assays on the augmentative effect of Beauveria bassiana GHA strain with insecticides, and its compatibility with fungicides were tested. Varying egg mortality was observed for most insecticides except for milbemectin. Pyrifluquinazon was less effective against the nymphs. Flonicamid showed no insecticidal effect on either nymphs or adults. However, increased mortality in nymphs and adults was observed when flonicamid was mixed with Beauveria bassiana GHA strain. Furthermore, no significant synergistic effect of mixing pesticides with B. bassiana GHA strain was observed. Most insecticides (when not mixed with B. bassiana) showed high (>80%) mortality against B. tabaci nymphs and adults. Most fungicides tested showed no inhibitory effects on B. bassiana GHA strain against B. tabaci nymphs and adults. Fungistatic effect was observed in the mycelial and spore germination inhibition studies. Weekly rotation of some pesticides with B. bassiana GHA strain in greenhouse conditions yielded significant reduction in different growth stages of B. tabaci. However, no significant difference in viral incidence was observed.CONCLUSIONLaboratory and field tests showed positive effects of augmenting pesticides and B. bassiana GHA strain against B. tabaci nymphs and adults. Therefore, augmentation of pesticides and B. bassiana GHA strain is one prospect towards developing an effective B. tabaci IPM system. © 2020 Society of Chemical Industry

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