不同类型抗虫棉品种的产量表现和氮素营养效率研究

以7个转Bt(Bacillus thuringiensis)基因抗虫棉(Gossypium hirsutumL)品种(美国品种33B,国产常规棉鲁棉研21、22、28、29,国产杂交棉鲁棉研15和25)为材料,分别在临清和东营种植,比较研究了它们的产量表现和营养效率。结果表明,国产常规抗虫棉品种平均比美国品种33B增产12.5%(临清)和28.3%(东营),抗虫杂交棉则比常规棉增产9.7%。早发型棉花品种(鲁棉研21和29)每生产100 kg皮棉所吸收的氮素量比后发型品种(鲁棉研22和28)少13.9%,营养效率系数高20.4%;杂交种(鲁棉研15和25)每生产100 kg皮棉所吸收的氮素量比常规种少13.8%,营养效率系数高16.8%。早发型棉花品种的氮素营养效率高于后发型,杂交种的氮素营养效率高于常规种。选用棉花杂交种或早熟、高产、经济系数高的常规种,创造正常的棉花熟相是提高氮素营养效率的重要途径。

Genotypic variations of yields and nitrogen nutrition efficiencies in Bt transgenic cotton

Seven Bt （Bacillus thuringiensis）transgenic cotton （Gossypium hirsutum L.）cultivars including 33B from USA, domestic inbred cultivars SCRC21, SCRC22, SCRC28, and SCRC29, and domestic hybrids SCRC15 and 25 were grown in Linqing and Dongying, and managed under normal fertilization. Their yields and nitrogen nutrition efficiencies(NNE)were comparatively examined. The results show that the average yields of the 4 domestic inbred cultivars are 12.5%(Linqing)and 28.3%(Dongying)higher than those of 33B, and are about 9.7% lower than those of the hybrids. Total quantity of nitrogen(TQN)for producing 100 kg fiber of the early-developed(ED)cultivars is 13.9% lower than that of the later-developed(LP)cultivars, and the nitrogen nutrition efficiency coefficient(NNEC)of ED is 20.4% higher than that of LP. TQN of the hybrids is 13.9% lower than that of the inbred cultivars, resulting in 16.8% increase in NNEC relative to that of the inbred cultivars. These results suggest that NNE of ED and the hybrids is better than that of LD and the inbred. NNE can be improved by adoption of hybrid or inbred cultivars with early maturity, better yield and high economic index. NNE is closely related to maturity performance. Realization of normal maturity performance with proper agronomic practice is also important for improving NNE.