Journal of Advances in Biology & Biotechnology

Background: The whitefly (Bemisia tabaci) (Hemiptera: Aleyrodidae) is a destructive insect pest and vector of begomo viruses, which transmits virus diseases in several important crop plants leading to severe losses in yield and quality.

Aims: Whitefly population and weather data, including temperature (minimum and maximum), minimum relative humidity, and maximum relative humidity, were correlated. The effectiveness of several compounds against whiteflies on roses.

Study Design: RCBD (Randomized Complete Block Design) was the method used in the experiment. The polyhouse, which was separated into three equal-sized blocks (14.6 m × 1.52 m), was used to plant the rose variety "Top secret." Eleven subplots, each measuring 1.11 m by 1.52 m, were created from each block. Five plants were cultivated at a suggested spacing of 35 cm by 25 cm in each plot.

Place and Duration of Study: The present investigation was worked out in the experimental block of Division of Floriculture & Landscaping Architecture, SKUAST-K, Shalimar campus, Srinagar from March 2022 to December 2022 under protected condition.

Methodology: Ten rose plants were chosen at random to be observed in a polyhouse setting in order to document the seasonal occurrence of whiteflies. Observations were made with a hand lens (10X). One day before the initial spray, the pre-count of whiteflies on roses was taken. Post-count observations were made at 1, 3, 7, and 15 days following the spray. Three randomly chosen plants from each treatment were observed. At intervals of 14 days, a second round of spraying was carried out, and the same observations were made. A statistical analysis was performed on the recorded data.

Results: The peak whitefly incidence on leaves was observed in 31^st SMW (3.55 whiteflies/leaf) at 20.4°C (minimum temperature), 33°C (maximum temperature), 66.7% (minimum RH) and 88.5% (maximum RH) whereas peak whitefly incidence on flowers was observed in 28^th SMW (11.05 whitefly/flower) at 20°C (minimum temperature), 29.5°C (maximum temperature), 92% (maximum RH) and 70% (minimum RH). Correlation studies revealed whitefly population to be positively and highly significantly correlated with temperature (minimum and maximum) while highly significantly and negatively correlated with RH (minimum and maximum). Regression analysis revealed 65.3 and 55.9 per cent variation in whitefly population on leaves and flowers respectively due to weather parameters. In management of whitefly/leaf/flower, T₆ (Acetamiprid 20% SP @ 0.2g/L) was reported as most effective treatment followed by T₇ (Thiamethoxam 25% WDG @ 0.3g/L).

Conclusion: The peak incidence of whitefly was observed in August. Use of different newer molecules along with entomopathogens and botanicals and also use of bio control agents for the control of whitefly.