腰果叶片氮磷钾年周期变化及再吸收效率

Annual Variation and Resorption Characteristic of Leaf N,P and K of Cashew

以6龄腰果无性系FL30为对象,采集全年12个月腰果成熟叶片样品,分析腰果叶片N、P、K年周期变化规律;并采集腰果衰老叶片样品,分析腰果树N、P、K再吸收效率。结果表明:腰果叶片N、P、K含量随生育期的改变而变化;叶片N含量从抽梢期至果实成熟呈上升趋势,果实成熟后明显下降,休眠期叶片N含量变化不大;叶片P含量从抽梢期至初果期总体呈下降趋势,初果期至休眠期则呈上升趋势;叶片N/P呈现出与N相似的年周期变化规律;叶片K含量在抽梢期呈下降趋势,初花期骤然上升,盛花坐果期继续缓慢上升,果实生长期至休眠期则呈下降趋势;腰果成熟叶片N、P、K含量显著高于衰老叶片,N、P、K再吸收率较高,再吸收效率顺序为REP>REN>REK。

Six years old cashew clone FL30 was employed to investigate the annual variation characteristic of N, P and K of cashew leaf. The resorption characteristic of N, P and K of old cashew leaf was analyzed. The results indicated that the concentration of N, P and K of cashew leaf changed with the cashew growth period. The concentration of N increased from flush period to fruit maturation period, declined obviously after fruit matured, but didn＇t change too much in dormant period. The concentration of P declined from flush period to initial fruit set period, and then increased until dormant period. The variation characteristic of leaf N/P was similar with leaf N concentration. Leaf K concentration declined during flush period, increased suddenly at initial flowering period, continually increased slowly in full flowering and fruit set period, and then declined from fruit growth period to dormant period. The concentration of N, P and K of mature cashew leaf was obviously higher than that of cashew old leaf. The nutrient resorption efficiencies of N, P and K were high, and the order was REP〉REN〉REK.