Vol. 12, Issue 10 (2023)

Author(s):
Tamilselvan Sakthivel, Perumal Renukadevi, M Suganthy, A Sankari and B Rajagopal

Abstract:
Bitter gourd is an important vegetable crop, which is well known for its nutritive and medicinal value. For the last five year, bitter gourd cultivable area is gradually decreasing by a devastating yellow mosaic disease. The disease is caused by two important Begomoviruses viz., Tomato leaf curl New Delhi virus (ToLCNDV) and Bitter gourd yellow mosaic virus (BgYMV). In which, ToLCNDV is more prevalent in Coimbatore district of Tamil Nadu. The survey indicated that the disease incidence was from 58.1 to 89.3% in five locations viz., Agarapatti, Narasipuram, Pappampatti, Thondamuthur and Vellimalaipattinam. The incidence was high at Pappampatti village with 89.3% with high whitefly population of 8.75/plant. The PCR analysis confirmed the presence of ToLCNDV in all the five locations by using specific primers for specific for the AV1 and AC3 regions. The Pappampatti isolate of ToLCNDV (ToLCNDV BGPP; Accession number-OR051905) was sequenced and BLAST search showed 98.01% similarity with ToLCNDV isolate of tomato (MT890778) and bitter gourd isolates (MT966792) from Karnataka. The ToLCNDV BGPP isolate was successfully transmitted by a group of 20 whiteflies with 93.33% transmission efficiency. The ToLCNDV BGPP was detected in whiteflies after 24h AAP and 24h IAP through PCR. Out of 15 plants transmitted with whiteflies, five symptomatic and nine asymptomatic plants were positive for ToLCNDV specific primers.