不同产量结构小麦品种对缺磷反应的分析

Response to Phosphorus Deficiency of Two Winter Wheat Cultivars with Different Yield Components

有关作物对缺磷反应的研究很多 ,但较少涉及到不同产量结构品种的反应差异 ,而这一点对于磷高效育种至关重要。本研究利用大田试验分析了缺磷对产量结构不同的两个品种的影响及原因。试验结果表明 ,缺磷较轻的条件下(Olsen P 6 .6mg kg,施磷P 30kg hm2 ) ,多穗型品种农大 32 91的产量显著减少 ,其原因是成穗数下降 ;中间型品种京 94 2 8的产量及产量因素无显著变化 ;严重缺磷的 (Olsen P 2 .4mg kg ,不施磷 )条件下两个品种对缺磷的反应相同 ,产量及产量因素都减少 ,穗粒数减少的幅度最大。其原因是磷营养的严重匮乏使小穗、小花的数目大幅度减少 ,进而使穗粒数也大幅度减少。对小麦籽粒淀粉累积过程的观察发现小麦籽粒中淀粉的累积基本不受缺磷的影响 ,因而缺磷对千粒重影响较小。

Numerous researches have been done on the response of crops to low phosphorus (P) deficiency, but few is involved in the yield structure of the research materials, which is very crucial for crop P efficiency breeding. The present study analyzed the response to P deficiency of two winter wheat cultivars with different yield components, ND3291(numerous ears) and J9428(few ears). When P deficiency was not serious(olsen-P 6.6 mg/kg, P applied 30 kg/hm 2), the yield of ND 3291 was reduced significantly, which was due to the decrease of ear number .Under this condition, yield and yield components of J9428 were not reduced significantly. When P deficiency was serious(olsen-P 2.4 mg/kg, No P), the effect of P deficiency on two cultivars was identical. Yield and yield components of the two cultivars were all reduced. Among three yield components, ear grain number was reduced greatest. It is because that the low P nutrition level of plant leaded to the decreasing of the number of spikelets and florets per ear. The results also showed P deficiency didn't affect the starch accumulation in grains, so P deficiency had less impaction on thousand-grain weight than other yield components.