Characteristics of yield components and population quality in high-nitrogen- utilization wheat cultivars

Abstract

In the rice-wheat rotation system, 24 and 23 wheat cultivars were separately planted in Yangzhou and Suining of Jiangsu province in 2016-2017 and 2017-2018. According to nitrogen utilization rate (NUR), these cultivars were clustered into three groups, i.e., NUR-H (NUR ≥ 50%), NUR-M (NUR 40%-50%), and NUR-L (NUR ≤ 40%), to identify the differences in grain yield, yield components, and population quality, which would provide a reference for cultivar selection for high-yield and high-efficiency in wheat production. Yangmai 25 and Ningmai 21 in Yangzhou and Huaimai 35 in Suining showed NUR-H phe

Study on the Nutrient Optimal Management Strategy of High and Stable Annual Yield in the Rice–Wheat System: A 10-Year Term Experiment

“…Differences in biomass accumulation directly reflect yield formation [11,12,18,19,40]. In our study, at rice season, the year-to-year fluctuations of dry matter accumulation at the jointing-heading stage and after heading were higher than before jointing.…”

“…On the one hand, reducing the nitrogen fertilizer rate in the early growth stage was beneficial to control ineffective tillers, forming a healthy population with good ventilation due to the low nutrient absorption of rice and wheat in this period [7,11,12]. Providing sufficient nutrients during the middle and later growth stage could promote the differentiation of spikelets, reduce the amount of degradation, form a greater number of spikelets and the higher spikelets-leaf ratio [6,11,17,18]; simultaneously, high-efficiency leaves could maintain strong photosynthetic potential and long photosynthetic duration after heading, providing sufficient carbohydrates for yield formation [11,12,18,19,31]. On the other hand, organic amendment application (straw and organic fertilizer) could remarkably improve soil quality and strong ability for immobilization fertilizer-nutrient of fore-crop and current season [13,15,32,33].…”

“…It was due to coordination with the law of fertilizer demands of rice and wheat, namely reducing the amount of fertilizer at the early growth stage and increasing nutrient supply at the late growth stage. Some studies reported that increasing the spikelets number of wheat and rice and promoting biomass accumulation after heading based on guaranteeing the full number of productive tillers was key in the nutrient management of high and stable yield [6,11,[16][17][18][19]. However, many studies only focus on a single-season crop in rice-wheat rotation systems, lack of assessment annual yield, especially yield stability evaluation.…”