Effect of preharvest spray of plant growth regulators on size, composition and storage behaviour of coorg mandarins [ Citrus reticulata (blanco)]

Mandarin orange trees bearing the monsoon crop* were sprayed with CLPA and 2,4,5‐T and NOA 8 weeks before harvest. Fruits treated with 2,4,5‐T (25 and 50 ppm) and CLPA (25 ppm) had 34, 35 and 28% more weight, respectively, than the control and also had higher percentage of juice and reduced pomace content with a corresponding increase in peel moisture. When stored for 35 days at 42‐45° F and 85‐90% R.H., the treated fruits suffered less physiological loss in weight, a greater percentage of them being in marketable condition as compared with the untreated ones. The vitamin C loss also was much less during storage. The treatments had little effect on respiratory activity, although there was a peak on the fourteenth day of storage, possibly a respiratory climacteric.