Post-harvest decay and biochemical changes in kinnow fruits in relation to pre-harvest spray schedules

Spray schedules comprising carbendazim @ 0.1% and propineb @ 0.2% proved significantly superior to rest of the spray treatments in controlling post-harvest fruit decay during cold storage to the extent of 77.99 and 73.73 per cent, respectively over control, differing nonsignificantly to each other. Spray schedules of yeast bioagent Sporidiobolus pararoseus (KFY-1) @ 10⁹ cfu/ml and carbendazim 12% + mancozeb 63% @ 0.15% were found to be next in terms of efficacy against post-harvest spoilage, provided 62.70 and 56.80 per cent protection, respectively. Out of eight fungi found associated with the decayed fruits during cold storage, Botryodiplodia theobromae, Colletotrichum gloeosporioides, Alternaria alternata, Penicillium digitatum and P. italicum were responsible for more than 85 per cent fruit rotting. Maximum total soluble solids were determined in fruits sprayed with carbendazim (14.60%) statistically at par with GA₃ (13.90%) but significantly higher than control. Fruits sprayed with mancozeb, propineb, yeast bioagent S. pararoseus, mixture of carbendazim 12% + mancozeb 63%, copper oxychloride and carbendazim rendered at par acidity (1.03–1.14%) but significantly less compared to control. Gibberellic acid (34.96 mg/100 ml) and mancozeb (33.71 mg/100 ml) provided significantly higher ascorbic acid as compared to control.