旱地高产小麦品种籽粒锌含量差异与产量构成和锌吸收利用的关系

【目的】 明确旱地条件下高产小麦品种籽粒锌含量差异与产量构成及锌吸收利用的关系，对通过品种选育和施肥调控提高旱地小麦籽粒产量和锌营养，实现小麦高产优质生产有重要意义。 【方法】 于2013—2016年连续三年在黄土高原典型旱地进行了小麦裂区田间试验。 以我国主要麦区的123个小麦品种为试材，每个品种设置不施肥和施N 150 kg/hm2、P₂O₅ 100 kg/hm2两个处理。分析了高产小麦籽粒锌含量差异及其与干物质累积、产量构成、锌吸收和分配之间的关系。 【结果】 施肥条件下，高产小麦品种籽粒锌含量存在显著差异，小麦籽粒锌含量与籽粒产量间无显著相关性，但与千粒重、锌吸收量、锌收获指数和籽粒锌形成效率呈显著正相关，与穗粒数呈显著负相关。在高产品种中，无论施肥与否高锌品种的籽粒锌含量均显著高于低锌品种；高锌品种的籽粒锌含量因施肥而显著提高，低锌品种却降低。施肥条件下，高锌品种的籽粒产量、生物量和收获指数与低锌品种相比无显著差异，穗数却显著降低；高锌品种的籽粒锌吸收量、地上部锌吸收量、锌收获指数和籽粒锌形成效率均显著高于低锌品种。且高锌品种的产量、生物量、穗数、穗粒数和锌吸收量因施肥引起的提高幅度均亦显著高于低锌品种。 【结论】 在黄土高原旱地低锌土壤上，无论是品种选育还是施肥调控，促进小麦锌的吸收和向籽粒的转移是提高小麦籽粒锌含量的关键。

Grain zinc concentration,yield components,and zinc uptake and utilization of different high-yielding wheat cultivars in dryland fields

【Objectives】 Grain zinc (Zn) concentration varies among cultivars of wheat. The uptake and utilization of Zn are also different from one cultivar to the other. Studying the characteristics of cultivars in Zn nutrition will provide valuable information for improving wheat yield and grain Zn contents through breeding. 【Methods】 A split field experiment was conducted for three growing seasons in the typical dryland area of the Loess Plateau from 2013 to 2016. 123 wheat cultivars, collected from the main wheat production areas in China, were grown under two treatments of no fertilizer control and applying N 150 kg/hm2 and P₂O₅ 100 kg/hm2. The Zn concentrations in grain and their relationship with dry matter accumulation, yield components, Zn uptake and utilization were investigated. 【Results】 Significant differences were found in grain zinc concentration among high-yielding wheat cultivars under fertilization. Grain Zn concentration was not correlated with the grain yield, but was positively and significantly correlated with thousand-grain-weight, Zn uptake, Zn harvest index and grain Zn formation efficiency, negatively and significantly correlated with grain number per spike. Among the cultivars, high-Zn cultivars had significantly higher Zn concentration than low-Zn cultivars regardless of fertilization. Moreover, fertilization led to higher grain Zn concentration in high-Zn cultivars, but the opposite was true for low-Zn cultivars. Under fertilization, there was no difference between high-Zn cultivars and low-Zn cultivars in grain yield, biomass, and harvest index, but the former had lower spike number, and higher Zn uptake in grain and aboveground part, Zn harvest index, and grain Zn formation efficiency than the latter. High-Zn cultivars had greater fertilizer effects than low-Zn cultivars on grain yield, biomass, spike number, grains number per spike. 【Conclusions】 The key to increase wheat grain zinc concentration through breeding or crop management is to promote zinc uptake and its allocation to grains in low-Zn soils in the typical dryland area of the Loess Plateau.