The diamondback moth Plutella xylostella: ecological and biological aspects, harmfulness, population control

Abstract

Data on prevalence, biological and physiological characteristics of the diamondback moth Plutella xylostella (Lepidoptera: Plutellidae) are presented. Pest damage is described. Reasons causing increase in harmfulness and economic importance of the insect are noted. An increase in the number of generations able to develop during growing season and earlier pest emergence are recorded under conditions of Siberian region. Factors contributing to the insect density dynamics, including plant species and variety, entomophagous arthropods and entomopathogenic microorganisms, have been considered. Range of chemical insecticides recommended for diamondback moth management in Russian Federation has been indicated. An increase in resistance to chemicals and certain entomopathogens in P. xylostella populations in different regions of the world has been recorded. Possibility of pheromone traps exploitation for efficient pest detection and monitoring has been established. Perspectives of novel efficient and safe means of pest density regulation have been defined.

Spore yield of the microsporidium Nosema pyrausta (Paillot) Weiser, 1961 is influenced the insect host rearing temperature and diet composition

“…Microsporidia are unicellular parasitic eukaryotes that play an important role in population dynamics of lepidopteran insects (Solter et al, 2012;Malysh et al, 2013;Frolov, 2019;Issi, 2020;Andreeva et al, 2021). Nosema pyrausta (Paillot) Weiser, 1961 is a widespread pathogen of the European corn borer Ostrinia nubilalis (Hübner, 1796) (Pyraloidea: Crambidae), causing increased larval mortality (especially during hibernation), retarded larval development, reduced adult fecundity, and enhanced susceptibility of the insects to chemical and microbial insecticides (Siegel et al, 1988;Pierce et al, 2001;Lopez et al, 2010).…”

Results of testing of the efficacy of sublethal concentrations of bacterial-chemical insecticides combinations against cabbage moth larvae

“…Hatched larvae eat the parenchyma of the leaves, leaving the epidermis intact, resulting in the formation of areas covered with a thin membrane, called "windows" (Avetyan & Marjanyan, 1976), and the more mature larvae open through holes on the leaves. The damage becomes more dangerous when they feed on the young leaves forming the head of the plant (Safaryan, 1968;Terlemezyan, 1996;Philips et al, 2014;Andreeva et al, 2021).…”