不同小麦品种吸收利用氮素效率的差异及有关机理研究 Ⅰ.吸收和利用效率对产量的影响

用盆栽试验研究了１２个冬小麦品种（ＴｒｉｔｉｃｕｍａｅｓｔｉｖｕｍＬ．）在低、高氮条件下的籽粒产量差异，及吸收和利用氮素的效率对其影响。结果证明在低氮处理中吸收效率和利用效率（ＵｔＥＧ）的共同影响导致了产量差异，但利用效率的影响更大；高氮处理则主要是吸收效率的影响，利用效率的影响较小。研究还发现能高效吸收或利用氮素的品种多为矮秆品种，因此高产品种多为矮秆。在低氮处理中的高产品种具有高效吸收或高效利用的特点；高氮处理中的高产品种主要具有高效吸收的特点，利用效率并不高。在所有品种中，只有低氮条件下的太核５０２５兼具高效吸收和高效利用的优点，说明多数品种的吸收、利用效率有待提高，以充分发挥氮肥的增产效果，达到少施氮肥多增产和保护环境的目的

Genotypic variations for nitrogen use efficiency in winter wheat I.Effects of N uptake and utilization efficiency on grain yields

The effects of nitrogen uptake,and utilization efficiency on the grain yields of 12 wheat genotypes ( Triticum aestivum L.) were studied in a pot experiment in green house with three replications at two rates of N supply.There were significant differences among genotypes for all the research traits at both N levels.Regression analysis indicated that both N uptake and utilization efficiency affected the genotypic variations for grain yields at low N;while N uptake was the main influencing factor at high N.At both N levels,the genotypes which efficiently absorbed,or utilized N were mainly dwarf;therefore,the genotypes with high grain yields were almost dwarf.The high yield genotypes at low N had high level efficiencies of uptake,or utilization,but the high yield genotypes at high N mainly had high level efficiencies of uptake.Only the genotype Taihe 5025 both absorbed and utilized N efficiently at low N,no such kind of genotypes was found at high N.This suggested that the N use efficiency of most genotypes should be improved to grain higher yields with less N supply.