Institute of Characteristic Crops Research, Chongqing Academy of Agricultural Sciences, Yongchuan, 402160, Chongqing, China.
Institute of Jiangxi Oil-Tea Camellia, Jiujiang University, Jiujiang, 332005, Jiangxi, China.
Sci Rep. 2024 Aug 22;14(1):19566. doi: 10.1038/s41598-024-70555-8.
Sorghum ratooning, a time and labor-saving cultivation practice, is increasingly being adopted by farmers in Southwest China as an alternative. Efficient N fertilizer management is critical for economical production of sorghum and the long-term protection of the environment. To investigate the impact of N management on grain yield and nitrogen use efficiencies (NUEs) of ratoon sorghum system, a three-year field experiment was conducted for Jinyunuo3 (a hybrid cultivar) and Guojiaohong1 (an inbred cultivar) using 12 combinations of N rates and splitting ratios. The results showed that increasing N rate and splitting application times led to improvements in various growth parameters such as dry matter weight, crop growth rate (CGR), leaf area index (LAI), and photosynthetic potential (PP). The main, ratoon, and annual yields increased with N rate increase, but there was no significant difference between 225 and 150 kg N ha in the ratoon and annual yields. Splitting the application of N fertilizer enhanced grain yield compared to a single dose application method, especially three-split applications yielded higher than two-split applications. Compared with N rates of 225 and 150 kg ha, N rate of 75 kg ha increased apparent recovery rate of applied nitrogen (RE), agronomic efficiency of applied nitrogen (AE), and partial factor productivity from applied nitrogen (PFP) in both main season and whole year. But through splitting application methods at high N rates could achieve similar or even higher levels of NUEs compared to all applied as basal fertilizer at low N rates. Therefore, it could be recommended that applying 150 kg N ha with a basal-jointing-heading fertilizer ratio of 2:4:4 represented an efficient N management practice to synchronously obtain high grain yield and NUEs in ratoon sorghum system in Southwest China.
高粱再生，一种省时省力的栽培方法，正越来越多地被中国西南地区的农民采用作为替代。高效的氮肥管理对于高粱的经济生产和环境的长期保护至关重要。为了研究氮肥管理对再生高粱系统的籽粒产量和氮肥利用率（NUEs）的影响，进行了为期三年的田间试验，采用 12 种氮素用量和分配比例组合，对金糯诺 3（杂交品种）和国窖红 1（自交品种）进行了研究。结果表明，增加氮素用量和分配次数可提高干物质重量、作物生长率（CGR）、叶面积指数（LAI）和光合潜力（PP）等各种生长参数。主季和再生季产量均随氮素用量的增加而增加，但再生和年际产量在 225 和 150 kg N ha 之间没有显著差异。与单剂量施肥相比，氮肥分次施用可提高籽粒产量，尤其是三次分施的产量高于两次分施。与 225 和 150 kg N ha 的氮素用量相比，75 kg N ha 的氮素用量增加了主季和全年的表观氮回收率（RE）、氮肥农学效率（AE）和氮肥偏生产力（PFP）。但通过在高氮用量下采用分次施肥方法，可以达到与低氮用量下全部作为基肥施用相似甚至更高的氮肥利用率水平。因此，推荐在西南地区再生高粱系统中，采用 150 kg N ha 的氮素用量，基肥-拔节肥-穗肥比例为 2:4:4，是一种高效的氮肥管理实践，可以同步获得高籽粒产量和氮肥利用率。
