施氮量对不同花生品种积累氮素来源和产量的影响

Effects of nitrogen application on source of nitrogen accumulation and yields of different peanut cultivars

利用盆栽试验和15N示踪技术,研究了不同施氮量对两个花生品种氮素积累来源和产量的影响。结果表明,两个花生品种的茎、叶片,果针、幼果,根的干物重均表现出随着施氮量的增加而增加的趋势。大花生品种花育17号的荚果产量随着施氮量的增加而增加,而小花生品种白沙1016在施N 09~0 kg/hm2范围内表现为随着施氮量的增加显著增加,但过多施氮（N 135 kg/hm2）荚果产量反而下降,说明两品种对氮肥的增产效应存在差异。两个花生品种均随着施氮量的增加吸收土壤氮和生物固氮量而增加,表明增施氮肥促进了花生植株对土壤氮的吸收和对大气氮的固定。在施氮量01~35 kg/hm2下,花生吸收土壤氮的比例在41.85%4~8.63%之间,吸收肥料氮的比例在0%1~3.93%之间 生物固氮的比例在41.25%5~6.85%之间。吸收肥料氮的比例随着施氮量的增加而增大,生物固氮的比例随着施氮量的增加而减小。

Effects of nitrogen application amounts on source of nitrogen accumulation and yields of two peanut cultivars were studied by using the method of pot culture and 15N tracer.The results indicate that dry matter weights of stem ＋ leaf,peg ＋ unfilled pod and root of the two cultivars are all increased under the higher nitrogen amounts.The pod yields of Huayu17 are increased along with nitrogen amount increases,while the pod yields of Baisha1016 are increased when nitrogen application amount is less than 90 kg/ha,the pod yield would decrease when the amount is larger than 135 kg/ha.These indicate the yield increasing effects of the nitrogen application are different.The nitrogen amount absorbed from soil and fixed from air are both improved along with the increases of nitrogen application amount,which shows that the increases of nitrogen application could enhance the nitrogen amount absorbed from soil and fixed from air by peanut plant.Proportions of nitrogen absorbed from soil,fertilizer and fixed from air by peanut are 41.85%48.63%,0%13.93% and 41.25%56.85% respectively.The proportion of nitrogen absorbed from the fertilizer is increased,while the fixed proportion is decreased along with the increases of nitrogen application amount.