糯玉米氮肥利用效率的基因型差异

Genotype Differences of Fertilizer-Nitrogen Use Efficiency in Waxy Corn

以近年育成的31个糯玉米(Zea maysL.ceratinaKulesh)品种为试材,对其氮肥吸收利用率(RE)、氮肥生理利用率(PE)、氮肥农学利用率(AE)和氮肥偏生产力(PFP)的差异进行了比较。结果表明,各品种以收获鲜穗、鲜籽粒或成熟籽粒为目的,其AE、RE、PE和PFP均存在显著差异。聚类结果显示,无论收获产品是鲜穗、鲜籽粒还是成熟籽粒,属于高产、高氮肥利用效率(NUE)的品种有6个,即凤糯2146、京科糯267、京科糯218、粤白糯1号、SW42和SAUWX02。与其他品种相比,这6个糯玉米品种的鲜穗、鲜籽粒和成熟籽粒的平均产量分别高17.9%、18.1%和28.6%,平均AE分别高45.2%5、0.2%和64.7%,平均RE分别高35.1%、35.1%和36.7%,平均PE分别高4.5%、9.7%和20.3%,平均PFP分别高17.9%1、8.1%和28.6%。相关分析表明,提高糯玉米氮收获指数,增加氮素在植株体内的运转率有利于NUE的提高。

Many researches have shown that the absorption, translocation and utilization of nitrogen varied markedly in different genotypes of corn. However, there are few reports on waxy corn in this field. In this study, 31 cultivars of waxy corn （Zea mays L. ceratina Kulesh） released recently within China were employed to evaluate their nitrogen use efficiencies （NUE） by indices of agronomic efficiency （ AE）, recovery efficiency （ RE）, physiological efficiency （ PE）, and partial factor productivity （PFP）. The field experiment was split plot design with nitrogen treatment （225 kg N/ha） or control （0 kg N/ha） as main factor, and the 31 cultivars were planted randomly in each plot. Five plants of each cultivar were sampled at anthesis, fresh ear harvest （21 days after anthesis） and physiological maturity stages, respectively for measuring nitrogen contents in different organs of leaf, leaf sheath, culm, tassel, bracteal leaf, ear axis and kernel. Results showed that there were significant genotype differences of N use efficiencies among the 31 cultivars in terms of AE, RE, PE, and PFP （Table 2-4）. Cluster analysis revealed that the cultivars with high yield potential and NUE for whatever product of fresh ear, fresh kernel or maturity kernel were FN 2146, JKN 267, JKN 218, YBN 1, SW42 and SAUWX02 （Fig. 1）. Compared with other cultivars, their average yields of the fresh ear, fresh kernel and maturity kernel were higher by 17.9%, 18.1% and 28.6%, the average AEs of the fresh ear, fresh kernel and maturity kernel were higher by 45.2%, 50.2% and 64.7%, the average REs of the fresh ear, fresh kernel and maturity kernel were higher by 35.1%, 35.1% and 36.7%, the average PEs of the fresh ear, fresh kernel and maturity kernel were higher by 4.5%, 9.7% and 20.3%, and the average PFPs of the fresh ear, fresh kernel and maturity kernel were higher by 17.9%, 18.1% and 28.6 %, respectively. It is confirmed by correlation analysis that increasing the N harvest index and N translocation rate may promote NUE in waxy corn.