光周期对青饲玉米养分吸收及利用的影响

Effects of Photoperiod on Nutrient Uptake and Utilization in Ensilage Corn

通过3个对光周期不同敏感型的玉米品种进行光周期试验,研究了光周期对玉米的营养生长及其N、P、K养分吸收及利用率的变化。结果表明,光周期对敏感型青饲玉米品种华农1号的地上部营养生长、根系生长和养分吸收有显著的调控作用,而对相对不敏感型的青饲玉米品种粤农9号的调控作用则不显著。华农1号在长日照条件下根干物重较短日照条件下增幅为390.38%,光周期相对敏感型品种大暑麦的增幅为119.34%,粤农9号的增幅为45.47%;华农1号与粤农9号吸收的N总量分别增加了42.42%和12.38%,吸收P总量分别增加了171.76%和12.23%,吸收的K总量分别增加了319.27%和62.42%。试验结果还表明,随着光照时数的延长,光周期敏感型品种在长日照条件下的N养分利用率提高了,而P、K养分利用率却与光周期敏感特性无显著直接关系。

Three representative corn varieties with different levels of photoperiod sensitivity were selected to study their growth, uptake and utilization of N, P and K nutrients under different photoperiods. The resuits showed that the photoperiod significantly regulated shoot and root growth and nutrient uptake of the photoperiod sensitive type of ensilage corn, Corn cultivar Huanong 1, but had no significant effects on the relatively non-sensitive one, Corn cultivar Yuenong 9. cultivar Huanong 1, the photoperiod sensitive cultivar, produced higher dry root weight under long photoperiod （16 hours of illumination） than under short photoperiod （10 hours of illumination）, which increased by 390.38 %, while relative sensitive cultivar Dashumai increased its dry root weight by 119.34 %, and the cultivar Yuenong 9 by 45.47 %; the cultivar Huanong 1 and Yuenong 9 increased the uptake of total N by 42.42 %, of total P by 171.76 % and 12.23 %, and of total K by 319.27 % and 62.42 %. In addition, with increased illumination hours, photoperiod sensitive varieties improved their N use efficiency under long illumination hours, hut the P and K use efficiency had no direct significant relation with photoperiod sensitivity.