Cereal Leaf Beetle Oulema Melanopus Research Articles

Comparative Efficacy of Bio Active Plant Extracts and Insecticides against Cereal Leaf Beetle (Oulema melanopus L.) Infesting Oats in North Kashmir, India

Experiment was carried out at farmers field near the Faculty of Agriculture, Wadura, Kashmir, India during 2021-22 to evaluate efficacy of various insecticides and botanicals against cereal leaf beetle Oulema melanopus (L.) (Coleoptera: Chrysomelidae) infesting Rabi Oats (Avena sativa L.) in North Kashmir. Among plant extracts and insecticides evaluated against O. melanopus, Abamectin proved to be most effective in causing huge mortality to grub population with decreasing number of grub were recorded as (24, 21.3, 8.3, 1.6 and 1 %) after 2,4,6,8 and 10 days of spray, respectively during 2021 followed by Thiamethoxam (32.6, 15.3, 8, 0.3%) after 2, 4, 6, 8 ad 10 days of spray. Same trend of results was observed in 2022 and the pooled data.  Among tested botanicals viz. neem and Artimesia; Artimesia was effective in declining the grub population with (44, 42, 41, 39 and 37%) after 2, 4, 6,8 and 10 days after spray. Severe infestation has been observed at maturity of crop and keeping in view the use as fodder to cattle it is necessary to inculcate the use of locally available botanicals for better health of cattle during the dearth period of fodder in Kashmir valley. Overall, the marginal farmers might be saved from any untoward by utilization of the bioactive plant extracts in management of this notorious pest.

Assessment of Agrocenosis Adaptability of Winter Wheat in the Conditions of the Foothill Zone of the Central Caucasus

This paper presents the results of multi-year research on the adaptability of winter wheat varieties to the conditions of the foothill zone of the Central Caucasus. Characteristics such as ductility and stability were used to assess varieties for conformity to the cultivation conditions. Plant homeostaticity served as the indicator of ontogenetic adaptability. Phenological observations and reports were carried out according to the state variety testing methodology. The species composition of weed vegetation was established using the Agroecological Atlas of Russia. Conventional insect accounting methods were used to consider phytophages and plants damaged by them. It was established that the dominant pests of winter grains in the early periods of vegetation include phytophage bugs and cereal leaf beetle Oulema melanopus L. The maximum number of phytophage bugs was noted during the earing-flowering period. The proportion of pathogens of spike Fusarium head blight, tan spot and Septoria spot prevailed in the pathogenic complex. In total, 36.7% of varieties, including Kuma, Deya, Esaul, Starshina, Delta, Nota and Antonina, were medium-resistant to Fusarium head blight damage. According to the results of a comprehensive assessment of winter wheat selection by the parameters of adaptability, productivity and resistance to diseases, highly plastic genotypes responsive to environmental factors were distinguished: Kuma, Deya, Veda, Tanya, and List 25 (bi = 2.2; 2,3; 2,1). The selection of varieties was based on the adaptive properties of winter wheat. Fusarium head blight decreased by 20.8% in the mixed variety Batko+Deya, and the yield of mixed variety crops increased by 9%. Methods for compiling mixed varieties and designing the mosaics of varieties in the area of grain agrocenosis are recommended.
 Keywords: winter wheat, sustainability of agrocenosis, productivity, ecological plasticity, mixed varieties

Effects of effective microorganisms (EM) and biostimulator formulations on the secretions of flavonoids from the winter wheat and on foraging and development of cereal leaf beetle Oulema melanopus

Effects of effective microorganisms (EM) and biostimulator formulations on the secretions of flavonoids from the winter wheat and on foraging and development of cereal leaf beetle Oulema melanopus

One-pot formation of aza-enolates from secondary amines and condensation to esters and alkyl bromides

Starting from commercial secondary amines, a one-pot procedure allows a direct access to enaminones through a one-pot deprotonation/oxidation/in situ re-deprotonation/acylation sequence without intermediate isolation of the intermediate Schiff base or its corresponding enamine tautomer. An alternative one-pot sequence involving a similar oxidation step followed by one or two alkylation steps yields, after acidic work-up, functionalized ketones directly from the parent amine. This process has been applied to an expeditious synthesis of the male aggregation pheromone of the cereal leaf beetle Oulema melanopus.

Targeted sugar provision promotes parasitism of the cereal leaf beetle Oulema melanopus

Parasitoids may often lack access to sugar (e.g. floral nectar) in agricultural settings. Strategically timed spraying of host plants with sugar solution may provide one means of enhancing parasitism at the same time as minimizing nontarget effects (e.g. benefiting the pest itself). Sucrose was sprayed in wheat fields of northern Utah (U.S.A.) to assess the effects on parasitism of the cereal leaf beetle Oulema melanopus by the larval parasitoid Tetrastichus julis. Early‐season sugar provisioning, when larvae of the pest were first hatching and parasitoid adults were newly emerged, did not affect the numbers of cereal leaf beetle larvae that matured in treated plots but increased parasitism rates of beetle larvae by four‐fold in 2006 and by seven‐fold in 2007. No net influx of adult parasitoids into plots was detected after the application of sugar. Locally‐emerging parasitoids may have spent less time searching for their own food needs versus hosts. A laboratory experiment also confirmed that access to sucrose significantly increased parasitoid longevity. The field experimental results obtained demonstrate that applications of sugar, implemented to target a key time of the growing season when benefits are maximized for parasitoids and minimized for their hosts, can strongly promote parasitism of the cereal leaf beetle in wheat fields.

The effect of combined infestation by cereal aphids ( Macrosiphum avenae (Fabr.) ( Sitobion avenae) and Rhopalosiphum padi (L.)) and cereal leaf beetles ( Oulema melanopus (L.)) on their population development and on yield of winter wheat

Previous clarification of the relationships between insect populations and damage by cereal pests has enabled the effect of combined pest infestation on the yield of winter wheat to be analysed more thoroughly. The cereal aphids Macrosiphum avenae (Fabr.) ( Sitobion avenae) and Rhopalosiphum padi (L.), each in combination with the cereal leaf beetle Oulema melanopus (L.), were investigated in pot trials which enabled interactions between the combined pest populations to be studied also. Although intraspecific competition was observed for each pest population, there was no interspecific adverse effect of density on population increase. With increasing population densities of the pests in combination, the relative contribution of each species to the combined yield losses decreased. Consequently, there was no summation of individual losses, but a reduction of up to 24·3%. The ability of the cereal plant to compensate for losses may be responsible for this ‘buffering effect’, which apparently is attributable to increased dry-matter production in the presence of large combined pest populations. These results suggest that the existing economic thresholds relating to the effects of cereal aphids and cereal leaf beetle on yields of winter wheat require modification.

Formulation of a mathematical model for insect pest ecosystems—The cereal leaf beetle problem

A general population model is developed as a partial differential equation to describe the maturity distribution of the population density as a function of time. The model is applied to the cereal leaf beetle Oulema melanopus (L.) (Coleoptera: Chrysomelidae) and its principal parasite Tetrastichus julis (Walker) (Hymenoptera: Eulophidae). Ordinary differential equations are developed to describe the growth of cereal grains such as oats for which the cereal leaf beetle is a major economic pest. The temperature dependency of the physiological processes is treated by introducing physiological time scales for the pest, parasite, and plant. Simplification of the pest and parasite models is accomplished through the use of mortalities at the transitions between life stages of the insects. The non-linearities due to density-dependent mortalities by both competition and parasitism are incorporated in the boundary conditions of the models. The selective attack probability of parasite adults on pest larvae characterizes the pest-parasite coupling in the boundary conditions. The pest population is coupled to the crop dynamics by the reduced leaf surface area which results from larval feeding. An analytical solution is presented for the pest dynamics. Procedures are given for evaluating the parameters in the coupled pest-parasite-plant model using field measurements. Results of a complete computer simulation of the coupled model and comparisons with experimental data are presented.

Resistance of Small Grains to The Cereal Leaf Beetle123

Studies of resistance in small grains to the cereal leaf beetle Oulema melanopus (L.), were conducted near Galien, Michigan, during 1963. Field-planted wheat, oat, and barley varieties (687) were examined for damage from adult and larval feeding, and the eggs and larvae were counted. Results indicated that wheats were preferred less than oats and barleys for oviposition and had less damage from adult and larval feeding. Wheats with highly pubescent leaves were largely avoided for oviposition; thus leaf pubescence may be a factor of resistance. A 14-chromosome wheat, Triticum persicum fuliginosum Vavilov, with highly pubescent leaves, had great resistance to the cereal leaf beetle.