author(s)
Kalpesh B More, Satish B Jadhav, Sachin D Magar, Prakash K Lokhande and Swati D Shinde

abstract
The study entitled “Effect of Plant Bioregulators on Colour Development in Table Varieties of Grapes (Vitis vinifera L.)” was conducted at MPKV, Rahuri (Oct 2024-Mar 2025) to address uneven ripening and enhance uniform colour development in four table grape varieties viz Red Globe, Crimson Seedless, Manjari Shyama and Sharad Seedless using plant bioregulators ABA (300 ppm), Ethylene (400 ppm) and control treatments in a Factorial Randomized Block Design. Results revealed significant varietal differences, with Manjari Shyama showing early ripening and superior anthocyanin content, while Red Globe recorded maximum berry size and yield. ABA @ 300 ppm improved yield, sugars content, anthocyanin concentration and shelf life, whereas Ethylene accelerated ripening and colour uniformity but reduced shelf life. Significant interaction effects indicated that treatment combinations, particularly Red Globe + ABA @ 300 ppm and Manjari Shyama + ABA @ 300 ppm, produced the best yield and quality traits. Overall, ABA and Ethylene effectively enhanced uniform ripening and colour development in table grapes.