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Prasad, K. V.

Publications and source records attributed to Prasad, K. V..

3 recordsLinked to original sources

Deciphering the Population Ecology of Blossom Midge, Contarinia maculipennis Felt: An Emerging Threat to Tuberose Cultivation in India

The blossom midge Contarinia maculipennis is a devastating pest of ornamental and vegetable crops, yet its population ecology remains poorly understood. This study employs an age-stage two-sex life table model to analyze its life history with additional focus on below-ground soil environment. Tuberose (Agave amica), a newly identified host, was selected for study. The average fecundity of C. maculipennis was 39.13 eggs, with an intrinsic rate of increase (r) of 0.137, and a mean generation time (T) of 19.73 days. The population doubling time was 5.05 days, with the highest survival rate observed in the first instar larvae (0.95), and the lowest in the adult stage (< 0.38). The population doubling time was 5.05 days. Survival was highest in first-instar larvae (0.95) and lowest in adults (< 0.38). Life expectancy peaked at age zero (e0 =15.57 days) and decreased with pivotal age. The reproductive value (Vx) peaked between 13 and 19 days post-field appearance. Pupal development was fastest, with a significantly higher adult-emergence recorded in sandy clay loam soil (9.67 days); however pupal development and adult-emergence were severely impacted in black cotton and marshy soils. Moderate soil moisture (20%) favored pupation and eclosion rate, while dry (10%) and saturated (30%) soils hindered pupation and emergence. Population projections over 90 days, starting with 133 eggs, estimated an adult population of 3,80738. These findings highlight pupal and adult stages as critical targets for management. Soil type and moisture strongly influence population dynamics, with strategies such as maintaining dry conditions between rows, deep ploughing to bury pupae, and mass trapping recommended for effective control. These insights offer practical strategies for the sustainable management of C. maculipennis.

ecology↗

New Record of Four Thrips Species Infesting Flower Buds of Magnolia champaca in India

The golden-flowered, highly fragrant local variety of Magnolia champaca, known as Sonchafa, is very popular loose flower crop in Maharashtra and adjoining states of India. In response to the rising thrips problems in Sonchafa (M. champaca) fields leading to significant economic losses, we looked into the thrips species composition infesting the plant in the Western Maharashtra region of India. Four thrips species were newly recorded as pests, including Psephenothrips machili (Moulton), Thrips florum Schmutz, Thrips hawaiiensis (Morgan) and Thrips orientalis (Bagnall). Among these, P. machili was identified as the dominant species, responsible for 63% to 71% of bud damage across various fields. This study also marks the first report of an anthophilous host association of P. machili with M. champaca, causing significant economic damage. The observed damage symptoms include, the typical distortion of flower tissues and buds, black spots on buds were ascribed to P. machili. The other three species were found in groups and caused silvery streaks on early-stage buds. The diagnostic characteristics of all the reported species are provided here, accompanied by photomicrographs.

zoology↗

Grey Pineapple Mealybug, Dysmicoccus neobrevipes Beardsley: A New Devastating Pest of Tuberose in India

Tuberose (Agave amica) is a highly valued flower crop in India, known for its consistently high returns and ability to thrive in various climatic conditions. Severe outbreaks of the grey pineapple mealybug, Dysmicoccus neobrevipes Beardsley (Hemiptera: Pseudococcidae), have been observed in several villages of the Pune district, Maharashtra (India), since 2021, leading to significant economic losses. This report provides an illustrative morphological diagnosis of D. neobrevipes and basic information on its field establishment, impact on tuberose crops, nature of the damage and field symptoms etc. Surveys conducted in major tuberose-growing areas of Pune district (Maharashtra) revealed that the mealybug primarily infests the underground and basal portion of tuberose plants, causing stunted growth, drooping, and ultimately death of the plants. D. neobrevipes produces honeydew, fostering sooty mold growth that impairs photosynthesis, reduces flower yield. It also infests tuberose bulbs, spoiling them in storage. Based on primary scientific literature, this study represents the first scientifically confirmed record of D. neobrevipes as a new pest of tuberose in India. The ant species Solenopsis geminata was found attending to mealybug colonies, aiding their spread and creating a nuisance for farmers during routine field activities. A total of 87.09% of the surveyed fields (n=62) showed mealybug infestation, ranging from 68% to 97%. Raising awareness among the farmers and implementing regular monitoring in tuberose-growing areas are crucial steps for developing effective management practices and preventing the further spread of this pest to other regions.

zoology↗