INDERJEET SINGH, HEENA JAIN, SHIWANI CHAHAL, ANITA RANI, PRABHAT KUMAR, SATISH KUMAR SAIN AND PRIYANKA SIWACH*
Department of Biotechnology, Ch. Devi Lal University, Sirsa-125 055 (Haryana), India
*e-mail: priyankasiwach@cdlu.ac.in; Mobile: 94669 15002)
(Received: January 5, 2024; Accepted: February 23, 2024)
ABSTRACT
Cotton is one of the major agricultural cash crops worldwide as well as in the Indian subcontinent. Cotton production in India is severely affected by cotton leaf curl virus disease (CLCuD), caused by a complex of CLCuD-associated begomoviruses (CABs) transmitted by whiteflies (Bemisia tabaci). Lately, CLCuD incidence was found to occur in some unpredictable patterns. To assess the disease incidence, the survey was conducted in different locations in the north cotton growing zone of India during the years 2022 and 2023. The per cent disease incidence and per cent disease index (PDI) were recorded based on the morphological symptoms of CLCuD and disease severity grades. The CLCuD incidence was 100% in all the three states during 2022, however, during 2023 it was low and ranged from 13.8 to 23.3%. The PDI of CLCuD varied from location to location in all the three states. During 2022, it ranged from 53.38 to 61.09 % in Haryana, from 49.77 to 54.38% in Punjab and from 53.08 to 56.42% in Rajasthan. However, the PDI was drastically low during 2023 and ranged from 10.27 to 12.7% in Haryana, 5.97 to 10.27% in Punjab and 9.47 to 12.11% in Rajasthan. The huge variability in incidence and PDI indicates the possible role of climate change and recombination in CABs and emphasizes the need to continuously monitor, and to map the disease incidence with climate as well as with the emergence of recombinants to develop suitable management strategies.
Key words: Cotton leaf curl disease, per cent disease incidence, DRS, begomovirus