Optimizing Yield and Grain Protein in Soft White Winter Wheat with Split Nitrogen Applications
Optimizing Yield and Grain Protein in Soft White Winter Wheat with Split Nitrogen Applications
复制标题
DOI：
10.2134/agronj1994.00021962008600060017x
复制
发表时间：
1994-11
期刊：
影响因子：
2.1
通讯作者：
K. Sowers;B. Miller;W. Pan
中科院分区：
文献类型：
--
作者：
K. Sowers;B. Miller;W. Pan
软质白色小麦（Triticum aestivum L.）在过去的十年中，当低于正常的降水量和过度施肥导致土壤残留氮水平过高时，华盛顿东部生产的土壤氮含量已经超过了市场期望的水平。在4个试验点进行了一项田间试验，目的是（i）研究高氮土壤条件下氮素对软质白色冬小麦产量-蛋白质关系bip的影响，（ii）确定分次施氮是否能保持产量和降低籽粒蛋白质，（iii）评估中期籽粒分析作为最终籽粒蛋白质预测因子。施氮量范围为0 ~ 140 kg N ha −1 ;定时处理为秋季种植前施氮和春季追肥或点注氮。施氮可获得高产（> 5900 kg ha −1），氮素对产量的影响范围为0 ~ 22%。秋季氮> 56 kg N ha −1仅在一个地点年增加产量;产量下降是由于另一个地点年过量施氮以及浅层氮耗竭和深层土壤水分提取不足。在四个地点年中的两个，产量增加了50%秋季-50%春季点注入氮相比，100%秋季应用在84公斤总氮公顷-1。在大多数土壤氮素在90厘米深度以下耗尽的地点年中，产生的蛋白质> 100 g kg-1;浅层氮素耗尽与蛋白质较低有关。成熟期籽粒氮浓度与乳熟后期和软面团期籽粒氮浓度高度相关。收获前对最终谷物蛋白质的预测可能有助于在收获时为销售目的分离谷物。在土壤残留氮水平较高的情况下，减少施氮量和秋、春分次施氮可以保持高产，降低籽粒蛋白质含量
Grain protein of soft white winter wheat (Triticum aestivum L.) produced in eastern Washington has increased above market-desired levels over the past decade, when subnormal precipitation and overfertilization contributed to excessive residual soil N levels. A field study was conducted over four site-years to (i) examine N effects on the yield-protein relationsbip of soft white winter wheat under high soil N conditions, (ii) determine if split N applications can maintain yield and reduce grain protein, and (iii) evaluate midseason grain analysis as a predictor of final grain protein. Nitrogen rates ranged from 0 to 140 kg N ha −1 ; timing treatments were fall preplant N and spring topdressed or point-injected N. High yields (> 5900 kg ha −1 ) were produced witbout fertilizer N, and yield responses to N ranged from 0 to 22%. Fall N > 56 kg N ha −1 increased yield in only one site-year; yields were reduced due to excess N fertilization in another site-year in conjunction with shallow N depletion and poor water extraction from deeper soil layers. In two of four site-years, yield increased with a 50% fall-50% spring point-injected N compared with 100% fall application at 84 kg total N ha −1 . Protein > 100 g kg −1 was produced in site-years where most soil N was depleted below the 90-cm depth; shallow N depletion was associated with lower protein. Grain N concentration at maturity was highly correlated with grain N concentration at the late milk and soft dough stages. Preharvest predictions of final grain protein may be useful in segregating grain at harvest for marketing purposes. Under high residual soil N levels, reduced N rates and split N applications between fall and spring can maintain high yields and reduce grain protein