Polyaspartic acid (PASP)-urea and optimised nitrogen management increase the grain nitrogen concentration of rice

Abstract

Increase in grain nitrogen concentration (GNC), which is directly affected by nitrogen (N) application, can help overcome the issues of malnutrition. Here, the effects of urea type (polyaspartic acid (PASP) urea and conventional urea) and N management method (two splits and four splits) on GNC and N concentration of head rice were investigated in field experiments conducted in Sichuan, China, in 2014 and 2015. N concentration of grain and head rice were significantly (P < 0.05) increased by N redistribution from the leaf lamina, activities of glutamine synthetase (GS), and glutamate synthase (GOGAT) at the heading stage, and N concentration and GOGAT activity in the leaf lamina at the maturity stage. Compared to conventional urea, PASP-urea significantly improved N concentration of grain and head rice by improving the activities of GS and GOGAT, thereby increasing N distribution in the leaf lamina. The four splits method, unlike the two splits method, enhanced N concentration and activities of key N metabolism enzymes of leaf lamina, leading to increased GNC and N concentration in head rice too. Overall, four splits is a feasible method for using PASP-urea and improving GNC.

Effect of Urea Coated with Polyaspartic Acid on the Yield and Nitrogen Use Efficiency of Sorghum (Sorghum bicolor, (L.) Moench.)

“…There are currently two main explanations concerning this. First, PAA is a hydrophilic and biodegradable polymer with a good dispersibility and adsorption capacity [41], and several previous studies have pointed out its capability in retarding the nitrogen release rate and promoting N utilization [24][25][26][27]34]. Second, Wang et al (2018) proved that PAA can increase maize nitrogen assimilation by enhancing nitrate reductase activity under hydroponic conditions [42].…”

“…Du et al (2011) indicated that PAA can inhibit soil urea nitrification and ammonization, thus extending the release of urea and reducing N loss [23]. A series of studies showed that PAA can enhance N utilization and promote rice dry matter accumulation, yield, and NUE in paddy fields [24][25][26][27]. However, related knowledge regarding the effects of PAA-coated urea on sorghum yield and nitrogen utilization, especially when combined with the one-time basal application method, is still limited.…”

Efficiency in nitrogen management using conventional and transgenic technology in the cultivation of maize

“…These can have repercussions on success since they are closely associated with crop yield. The efficiency of this nutrient is related to the application time for the crop development (Mar, Marchetti, Souza, Gonçalves, & Novelino, 2003;Deng et al, 2019), environmental conditions, soil, cultivars and interaction with other nutrients (Sims, Schepers, Olson, & Power, 1998). The application of nitrogen for top-dressing has maximized the utilization of this nutrient by the crop (Arf, Rodrigues, Nascente, & Lacerda, 2015).…”

Genome-Wide Association Analysis Dissects the Genetic Basis of the Grain Carbon and Nitrogen Contents in Milled Rice

“…As a staple food for more than half of the global population, rice is one of the most widely grown cereals worldwide and is critical for food security. Additionally, it is the source of about 25-50% of the daily protein intake of humans in developing countries, especially in Asia (Deng et al 2019). Carbon (C) and nitrogen (N) are two fundamental components of starch and protein, which are important determinants of grain yield and quality that influence the milling, appearance, eating and cooking qualities, nutritional qualities, and health benefits of grains (Martin and Fitzgerald 2002).…”