磷肥对小麦籽粒HMW-GS积累及GMP粒度分布的影响

Effects of Phosphorus Fertilizer on Accumulation of High Molecular Weight Glutenin Subunits and Glutenin Macropolymer Size Distribution in Wheat Grain

在112.5kghm-2和225kghm-2两种氮水平下,检测了施磷量对强筋小麦山农12籽粒高分子量谷蛋白亚基(HMW-GS)积累及谷蛋白大聚合体(GMP)粒度分布的调控效应。结果表明,小麦籽粒HMW-GS在花后14d已形成,成熟期籽粒HMW-GS含量表现为施磷处理高于不施磷处理。在低氮条件下,施磷有助于HMW-GS的积累,而在正常施氮条件下过多施磷则不利于其积累。在低氮条件下,粒径<10μmGMP颗粒体积百分比随施磷量增加而显著降低;在正常氮水平下,施磷降低粒径<10μmGMP颗粒体积百分比,其效应表现施磷0kghm-2处理最大,其次为施磷40kghm-2和100kghm-2处理,施磷160kghm-2处理最小。两种施氮水平下分别增施磷肥,粒径在10～100μm和>100μmGMP颗粒的体积百分比均呈现随磷肥用量增加而增加的趋势。在正常氮水平下,各施磷处理间籽粒中GMP颗粒数目百分比无明显差异。成熟期籽粒中HMW-GS含量与粒径<10μmGMP颗粒体积百分比呈显著负相关,而与10～100μmGMP颗粒体积百分比呈显著正相关。说明较大粒径GMP颗粒具有较高的HMW-GS含量。

For gaining insights into the relationship between the accumulation of high-molecular-weight glutenin subunit（HMW-GS） and the distribution of glutenin macropolymer（GMP） in wheat（Triticum aestivum L.）,Shannong 12,a cultivar with high glutenin,was used in a field experiment with four phosphorus（P） application levels（0,40,100,and 160 kg ha-） under low nitrogen（112.5 kg ha^-1） and normal nitrogen（225 kg ha^-1） conditions,respectively.The result showed that HMW-GS in grains formed before 14 d after anthesis,and its content at maturity was higher in P application treatments than in the treatment with no P fertilizer applied.Phosphorus was in favor of the accumulation of HMW-GS under the low nitrogen（N） condition,but caused a negative effect in high P levels under the normal N condition.The content of GMP particle in 10 μm in diameter was significantly reduced with increasing P application.The effect increased with increasing P level under the low N condition,but showed the largest reduction at P level of 100 kg ha^-1 and the smallest reduction at P level of 40 kg ha^-1.For GMP particle in 10–100 μm and 100 μm groups,their contents tended to increase with more P applied under both N conditions.Under the normal N condition,there was no significant effect of P level on the number distribution of GMP particle.At maturity,the content of HMW-GS was negatively correlated with the volume of GMP particle in 10 μm group,but positively correlated with that in 10–100 μm group.The result suggested that larger GMP particles have higher HMW-GS content than the smaller GMP particles.