Preliminary Studies on the Relationship Between Calcium and Fruit-Cracking in Litchi Fruit

A negative correlation was found between the calcitum content in litchi leaves and the rate of fruit cracking. The exchangeable calcium in the soil and the calcium contents in the leaves and fruit peel were significantly lower comparing the orchards where fruits severely cracked with the orchards of light fruit cracking. The calcium content in cracked fruits was significant higher than that in the normal fruits.Sprays with a solution containing calcium compounds increased significantly the calcium levels in the leaves and fruit peel, and significantly lowered fruit cracking rate. Water-stress reduced the calcium accumulation in fruit peel especially in the rapid growth of aril, and thus increased the fruit-cracking rate.It suggested that increasing calcium contents in leaves and the fluit peel should lower fruit-cracking in litchi.