S01 - Session P5 - Evaluation of World Vegetable Cente's ridge gourd F1 hybrids at the begomovirus hotspot in India

Authors: Kamal Yadav, Gopalkrishna Hegde, Suyuporn Lertlam *, Narinder Dhillon

Ridge gourd ( Luffa acutangula ) fruit is an important source of micro-nutrients and vitamin A for human diets. This gourd is also a significant to the livelihood of smallhold farmers in Asia as it can be cultivated in various agro-climates. Tomato leaf curl New Delhi virus (ToLCNDV) (genus Begomovirus , family Geminiviridae) can cause severe epidemics in this crop and therefore is a major constraint to ridge gourd production in Asia that can result in economically significant losses. From MarchnJune 2021, 15 ToLCNDV-resistant ridge gourd F1 hybrids developed at the World Vegetable Center (WorldVeg) were evaluated along with commercial hybrids in a randomized complete block design with two replications and 20 plants per plot under severe ToLCNDV pressure at an infection hotspot in Bangalore, India. Phylogenetic analysis of the nucleotide sequence of the Begomovirus DNA-A components amplified by PCR from infected ridge gourd leaf samples collected from the test fields confirmed infection by ToLCNDV strains. Worldveg F1 hybrids of the short fruit market segment, AVLA21693 (20.71 t/ha) and AVLA21463 (20.59 t/ha), yielded significantly ( P < 0.05) better than the commercial hybrid 'Rama' (13.37 t/ha). Worldveg hybrids of the medium fruit market segment, AVLA21699 (23.81 t/ha) and AVLA21622 (19.98 t/ha), achieved significantly ( P < 0.05) higher yields than the commercial references 'Aneeta (12.83 t/ha) and 'Arti' (14.33 t/ha). Fruit yields of long fruit market segment hybrids, AVLA21694 (19.51 t/ha) and AVLA21574 (18.95 t/ha), were comparable to the commercial hybrid 'Naga' (16.47 t/ha). WorldVeg hybrids remained virusfree 40 days after transplanting, whereas the commercial hybrids exhibited 50n90% virus incidence.