Studies on the effect of planofix on the control of preharvest drop in apple (Malus domestica Borkh.)

Effect of planofix to check the preharvest drop in Royal Delicious and Golden Delicious cvs of apple was studied at Regional Fruit Research Station, Mashobra during 1974 and 1975. Large scale field trials were also laid out during-1975 on Red Delicious, Golden Delicious and William’s Favourite cvs of apple in different, orchards at Kotgarh and Kotkhai. Planofix (10 ppm NAA as a.i.) when applied, 20 days before harvest reduced the fruit drop to less than 3% in both cultivars during the years under study. The respective fruit drop in control trees was 20% in Royal Delicious and 25% in Golden Delicious. A fortnight’s delay in picking showed heavy drop of fruits in control trees (44.4%, in Royal Delicious and 41.5% in Golden Delicious) but planofix (10 ppma.i.) checked this drop significantly (8.0% in Royal Delicious and 7.6% in Golden Delicious). Fruit weight and quality was unaffected by these treatments.