HORMONAL-CONTROL OF SPLITTING IN NOVA MANDARINE FRUIT

Fruit splitting, a physiological disorder of peel development in citru s, has been studied in terms of peel thickness and puncturing resistan ce in 'Nova' mandarins. Both features are negatively correlated with s plitting. A mixture of GA(3) and 2,4-D reduced significantly the perce ntage of affected fruits. The best results were obtained with two appl ications at 60 and 30 d before the anticipated onset of the disorder. Calcium nitrate applications have similar effects, but were ineffectiv e in orchards with a low natural incidence of splitting.