文冠果落果机理及提高座果率和种子品质的研究

STUDIES ON THE PREMATURE DROP MECHANISM, METHODS OF INCREASE FRUITAGE AND SEED QUALITY OF Xanthoceras sorbifolia Bge.

Shingleave yellow hern (Xanthoceras sorbifolia Bge.) is a domestic oil-producting tree species in China. Yet it has been found that, during young fruit period, a premature drop is very serious and the rate of fruit setting is only 2.2-6.3%.The present paper deals with the causes of premature drop in details and the methods for increasing yields.Experimental results show that genetic factors,insufficient organic nutrients during the blossom and young fruit periods and the increase of endangering ABA are the main factors causing the premature drops. From the fruit enlargening period till the ripening period, lack of water and nutrients are the dominant limiting factors which place restrictions on the development of the volume of seeds and the increase of the weight of a thousand seeds. It has been suggested that a fine variety is the key to raise output. We selected IMFC 2 and IMFC 52 as fine trees. The seed output of the two trees raised yields by 1.8 and 2.48 times in comparison with the eight su rrounding trees. After seed harvest, rejuvenating manure is applied to encourage well growth of spurs and to ensure enough nutrients for the growth of flowers and young fruits next year. The rate of fruit setting can be raised by 39.4%. During the fruit enlarging period if fruit fertilizers and enough water are supplied to ensure the development of fruits and seeds, then seed output can increase by 25.6%.