Population dynamics of cotton mealybug Phenacoccus solenopsis and its natural enemies Suroshe Sachin S.#, Gautam R. D., Chander Subhash, Fand Babasaheb B.* Division of Entomology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012 *ICAR-Central Cotton Research Institute, Nagpur, 441108 #Email: sachinsuroshe@gmail.com
Online published on 24 October, 2019. Abstract Studies revealed that, Brinjal (var. shyamala) planted on 31st July 2007 recorded highest (33.8 adults) cotton mealybugs, Phenacoccus solenopsis Tinsley, in March 2008 and lowest (0.93 adults) in November 2007, mealybugs found positively correlated with temperature. However, when planted on 14th July 2008 remained free from the mealybugs except scanty population noticed during January 2009. The other variety of Brinjal (var. Vikram) planted on14th July 2008 was found negatively correlated with rainfall (−0.21). The parasitoid, Aenasius arizonensis (Girault), was found negatively correlated with P. solenopsis (−0.21) and Promuscidea unfasciativentris Girault (−0.12). The highest (53.73 adults) population of P. solenopsis was observed during November followed by October (21.13 adults) and the lowest observed in December (1.3 adults) on sorrel planted in 2007. Highest (91.7 adults) population of P. solenopsis was observed during July followed by June (54.5 adults) and lowest was seen in December (1.3 adults) on sorrel planted in 2008. Mealybug found positively correlated with temperature in sorrel planted 10.07.2007 and 15.04.2008 Highest number of P. unfasciativentris were recorded in October 2008 (116 adults) on sorrel and observed negatively correlated (−0.2) with mealybugs. Okra planted 26.06.2008, recorded highest (11.08 adults) population of P. solenopsis during October as compared to lowest (3.4 adults) in November. It was positively correlated with temperature. Highest population of A. arizonensis was observed during October (23 adults), and found positively correlated with temperature (0.68) and P. unfasciativentris (0.11) which was highest in highest in November (26 adults). China rose recorded highest (51.82 adults) population of P. solenopsis in July 2008, while lowest (0.06 adults) in October 2008. Mealybug was positively correlated with temperature (0.53), relative humidity (0.67) and rainfall (0.61). Mealybug, was again found positively correlated with parasitoid, A. arizonensis (0.70), hyper-parasitoid, P. unfasciativentris (0.97) and hyperparasitoid, Aprostocetus purpureus Girault (0.73). Top Keywords Phenacoccus solenopsis, population dynamics, brinjal, China rose, sorrel, okra, parasitoids, hyperparasitoids. Top |