Incidence of invasive mealybug (Phenacoccus solenopsis Tinsley) on cotton

Abstract: Mealybug incidence was assessed in the scale of zero to four grades as well as percent incidence. Survey revealed that infestation ranged between zero to 3.62 through out the cotton growing Northern districts. Mealybug infestation on cotton was high in Thungabhadra Project area (TBP) and Upper Krishna Project area (UKP) which comprises of Bellary, Raichur and Gulbarga districts. Mean mealybug grade was as high as 3.42, 3.15 and 3.34 in Raichur, Gulbarga and Bellary districts, respectively as compared to Dharwad, Haveri and Belguam districts during 2008-09. Similarly, 2009-10, Phenacoccus solenopsis was severe in some parts of Bellary and Raichur districts and the mean infestation grade ranged between zero to 2.78 and zero to 2.58, respectively. Field infestation varied from 8.33 to 36.30 per cent in different talukas of North Karnataka. At Dharwad and Hubli talukas, several cotton fields were infested moderately with the mealybug and the per cent infestation ranged from zero to 18.5. Infestation in Gokak and Bailhongal taluks of Belgaum district ranged from zero to 24.22 per cent with a mean of 12.56 to 10.64 per cent, respectively. During 2009-10 cropping season, mean per cent infestation of mealybug on cotton across North Karnataka ranged from lowest of 2.96 in Dharwad district to highest of 12.47 in Raichur district