Saffron Bulb Mite Rhizoglyphus robini (Claparede) Its Occurrence, Biology and Chemical Intervention Tactics on Saffron Corms in Kashmir, India

Abstract

Saffron corms are attacked by a wide variety of arthropod pest species and mites are one of them. Among Arachnida class bulb mite causes considerable damage to saffron crop and presence of this pest is a regular feature in its cultivation. To record the occurrence of saffron bulb mite, field study was conducted at different saffron growing areas of Kashmir. For biology of the pest, laboratory study was conducted at Department of Entomology, Faculty of Horticulture, Sher-e-Kashmir University of Agricultural Sciences and Technology, Shalimar. The mean percent infestation of saffron bulb mite from all the locations revealed highest and lowest percent mite infestation of 25.83 and 12.50 recorded from Dhussu and Saffron research station respectively. Passing through five active stages viz., Egg, Larva, Protonymph, Tritonymph and adult completed the life cycle of Rhizoglyphus robini. The heteromorphic deutonymph or hypopal stage is sometimes produced for phoresis when population is overcrowded, but this stage was not observed during the study. The results revealed that the females laid their eggs on the corms. The average incubation period of egg was observed to be of 6.16 ±0.78 days while as other developmental periods Larva, Protonymph, and Tritonymph were of 5.22 ±0.68, 5.76 ±0.52, and 7.00 ±0.91 days at 25± 50C respectively. The longevity of adult male and female were 27.9 ±0.44 and 22.9 ±0.69 days respectively. The efficacy of different doses of acaricides against Saffron bulb mite revealed that drenching the soil with chlorpyrifos 20 EC + foliar spray with cyenopyrafen 30 SC showed best results with 4.23 percent leaves with stunted growth and chlorosis, 97.34 percent flower emergence and 2.23 percent bulb rot.