不同氮素处理对中麦175和京冬17产量相关性状和氮素利用效率的影响

本研究旨在了解我国黄淮和北部冬麦区不同施氮量和施氮模式对氮高效吸收和利用的影响,以及中麦175和京冬17产量对不同施氮处理的响应。2013—2014和2014—2015连续两年在河北吴桥和北京顺义两地种植两品种,观测不同施氮量和基追比处理下,冬小麦的群体特性、产量相关性状,以及氮素吸收效率(NUp E)和氮素利用效率(NUt E)。在吴桥点设0、60+0、120+0、120+60、120+120、120+180 kg hm~(-2)(基肥+拔节肥)6个处理,在顺义点仅设前5个处理。在总施氮量0~240 kg hm~(-2)(吴桥)和0~180 kg hm~(-2)(顺义)范围内,随施氮量增加,归一化植被指数(NDVI)和气冠温差(CTD)提高,群体总粒数和成熟期生物量增加,进而产量提高;但继续增加施氮量会导致粒重、开花前干物质向籽粒转运量、转运率、对籽粒贡献率、收获指数、氮肥偏生产力、氮素吸收和利用效率降低。在不同施氮水平下,中麦175的产量和稳定性均优于京冬17,表现出穗数多、穗粒重稳定性好、群体活力持久、生物量和收获指数高、花前干物质积累量高和花后干物质转运能力强、氮素吸收效率高,这可能是其高产高效的重要基础。考虑到产量回报和经济效益,推荐中麦175和京冬17在黄淮麦区(北片)施氮量为180~240 kg hm~(-2),在北部冬麦区施氮量为120~180kg hm~(-2)。灌浆中后期,NDVI和CTD与穗数、产量和生物量相关性高,可作为快速评价品种氮肥敏感性的指标。

Effect of Nitrogen on Yield Related Traits and Nitrogen Utilization Efficiency in Zhongmai 175 and Jingdong 17

The objective of this study was to understand the effects of different nitrogen (N) application amounts and split ratios on high efficiency of N uptake and utilization, as well as the response to different N treatments of Zhongmai 175 and Jingdong 17 planted in Wuqiao, Hebei, and Shunyi, Beijing in 2013–2014 and 2014–2015 cropping seasons. Nitrogen fertilizer was applied in different total and split (basal + jointing stage) amounts, namely 0, 60+0, 120+0, 120+60, 120+120, and 120+180 kg ha?1. In the N range of 0–240 kg ha?1 in Wuqiao and 0–180 kg ha?1 in Shunyi, the canopy temperature depression (CTD), normalized difference vegetation index (NDVI), biomass of wheat population, and population spikelets increased with the increase of N application amount, as a result, higher yield at maturity was obtained; however, further more N application had a negative effect, showing decreased thousand-kernel weight (TKW), translocation amount (TA) and efficiency (TE) of dry matter accumulated before flowering to grain, contribution efficiency (CE), harvest index (HI), partial factor productivity from applied N (PFPN), N uptake efficiency (NUpE) and N utilization efficiency (NUtE). Zhongmai 175 had higher yield and yield stability than Jingdong 17 in different N application treatments, showing higher levels of spike number (SN), stability of kernel number per spike (KNS), kernel weight, population vitality, biomass, HI, dry matter accumulation before flowering, TA, and NUpE. These characters might be the physiological basis of high yield and high efficiency in Zhongmai 175. Considering the return from yield and economic benefits, we suggest that the recommended N application amounts for Zhongmai 175 and Jingdong 17 should be 180–240 kg ha?1 in the northern part of Huang–Huai Rivers Valley Wheat Zone and 120–180 kg ha?1 in the Northern Winter Wheat Zone. NDVI and CTD at middle to late grain filling stage can be used for rapid evaluation of varietal sensitivity to nitrogen because they are highly correlated with SN, yield, and biomass of wheat.