麻核桃落果规律及影响因素

以不同品系麻核桃(Juglans hopeiensis Hu.)为试材,采用调查和生理测定的方法,研究了品种、树体方位、结果枝状态、果序位置、生理变化与麻核桃落果的关系,以期为麻核桃坐果率的提高和高效栽培管理提供参考依据。结果表明:麻核桃落果率在76.73%~94.77%,落果高峰在花后5~20 d,占总落果率的90%以上,生理落果高峰在花后55~80 d,是否有生理落果高峰因品种而异,中午的落果率明显高于白天其它时段;树体上层、外围、粗壮的斜生结果枝坐果率较高,果实序位对麻核桃落果有影响,落果率随序位的升高呈下降趋势;种仁和外果皮中高含量的ABA是果实脱落的原因之一,外果皮的ABA/(IAA+GA3+ZR)值显著高于正常果,可溶性糖、可溶性蛋白质、氮、磷、钾等营养物质不足是麻核桃生理落果的主要原因,研究结果对麻核桃园的高效管理具有一定指导意义。

Regularity and Influence Factors of Fruits Drop in Juglans hopeiensis Hu

The correlation between fruit drop and some relevant factors including cultivar,position in tree and infructescence,condition of seed bearing branch,and physiological changes in different varieties of Juglans hopeiensis Hu was investigated to provide theoretical basis for improving fruit-bearing rate and high-efficiency cultivation management.The results showed that the rate of fruit drop in Juglans hopeiensis Hu was from 76.73%to 94.77%.The peak period of fruit drop appeared from the 5 th to 20 th day after blooming,which accounted for more than 90%in the whole.The peak period of physiological drop occurred from the 55 th to the 80 th day after blooming.The existence of physiological drop peak period depended on different cultivar.The rate of fruit drop during noon was significantly higher than other time periods in daytime.Upper layer and peripheral of tree,sturdy and oblique bearing branches showed a higher fruit-bearing rate.The fruit position on the inflorescence affected fruit dropping.Rate of fruit drop tended to decrease with the increase of sequence number which representing the fruit position on inflorescence.High contents of ABA in kernel and epicarp was one of the reasons for fruit shedding.The value of ABA/(IAA+GA3+ZR)in the epicarp of shedding fruit was significantly higher than normal one.The deficiency from nutrient content such as soluble sugar,soluble protein,nitrogen,phosphorus and potassium was the main reason for physiological fruit drop of Juglans hopeiensis Hu.These valuable results can suggest to productively guide management in orchards of Juglans hopeiensis Hu.