水氮限量供给下高产小麦品种籽粒灌浆特性及氮磷钾积累动态

Grain-filling characteristics and accumulation dynamics of nitrogen,phosphorus and potassium in high-yield winter wheat cultivars under limited irrigation and nitrogen supply

选用华北地区两个主栽小麦品种济麦22和石麦15,在大田条件下,设置2个灌溉水平:春灌一水(W1)和春灌二水(W2);在每个灌溉水平下设置2个施氮处理:192kg/hm2(N1)和270kg/hm2(N2)。研究并探讨了在水氮限量供给下高产高效群体强、弱势粒灌浆特性及其籽粒氮磷钾积累的变化。结果表明,在籽粒灌浆期,两小麦品种强、弱势粒重均呈"S"型的变化趋势,而灌浆速率呈"抛物线"的变化趋势;且强势粒的粒重和灌浆速率显著高于弱势粒。在相同灌溉水平下,N1处理强、弱势粒灌浆持续天数均高于N2处理,而灌浆速率则低于N1处理;在相同施氮水平下,W2处理强、弱势粒灌浆持续天数高于W1处理。在不同水氮模式下,济麦22强、弱势粒重、灌浆速率和灌浆持续天数均高于石麦15。在籽粒灌浆期,两小麦品种籽粒氮磷钾积累量均呈"S"型变化趋势。在相同灌溉水平下,两小麦品种N2处理籽粒氮磷钾素积累量总体高于N1处理。在相同施氮水平下,W2处理籽粒氮磷钾素积累量均高于W1处理。在不同水氮模式下,济麦22籽粒氮磷钾素积累量高于石麦15。综合研究认为,适当水氮投入,提高了两小麦品种灌浆后期强、弱势粒灌浆速率,延长了灌浆持续期,促进了强、弱势粒均衡灌浆和籽粒中营养元素均衡分配,最终实现高产高效,对提高粒重和品质具有重要作用。

Irrigation-nitrogen regulation is one of the most important measures to increase crop yield in agricul- tural production. The two main local winter wheat cultivars, Jimai 22 and Shimai 15, were used in a field ex- periment to investigate their grain-filling characteristics and nitrogen, phosphorus and potassium accumulation dynamics under limited irrigation and nitrogen in the North China Plain. The experiment was carried out at the Wuqiao experiment station of China Agricultural University in the 2009--2010 growth seasons. There were two irrigation treatments： W1 （spring irrigation at jointing stage） and W2 （spring irrigation at jointing and an-thesis stages）; and two nitrogen fertilizer treatments： N1 （192 kg/ha） and N2 （270 kg/ha）. The results showed that at the grain-filling stage the grain weight of superior and inferior spikelets for both cultivars presented a ＂S＂ variation tendency, whereas the grain-filling rate presented a parabola variation tendency. The grain weight and grain-filling rate of superior spikelets was significant higher than inferior spikelets in both cultivars. Under the same irrigation level, grain-filling durations of superior and inferior spikelets in the N1 treatment were high- er than N2, whereas the grain-filling rate was contrary. Under the same N level, the grain-filling durations of superior and inferior spikelets in W2 was higher than Wl. Under different irrigation and nitrogen regimes, grain weight, grain-filling rate and durations of superior and inferior spikelets of Jimai 22 were higher than Shimai 15. During the grain-filling period, grain nitrogen, phosphorus and potassium accumulation amounts present a ＂S＂ variation tendency in both cultivars. Under the same irrigation level, grain nitrogen, phosphorus and po- tassium accumulation amounts in the N2 treatment were higher than N1. Under the same N level, grain nitro- gen, phosphorus and potassium accumulation amounts in the W2 treatment were higher than W~. Under differ- ent irrigation and nitrogen regimes, the grain nitrogen, phosphorus and potassium accumulation amounts of Ji- mai 22 were higher than Shimai 15. The results suggest that moderate irrigation and nitrogen supply enhances the grain-filling rate of superior and inferior spikelets at the late grain-filling stage, prolongs grain-filling dura- tions, promotes balance filling of superior and inferior grains and equilibrium in the distribution of nutrient ele- ments, improves grain weight and quality, producing in sum high yield gains and efficiency.