Effects of controlled-release urea application on the growth, yield and nitrogen recovery efficiency of cotton

Abstract

Field experiments were conducted to study the effects of the controlled release urea (CRU) application on growth yield and nitrogen recovery efficiency of cotton in the main cotton zone of the Yangtze River basin in 2010. Different nitrogen levels were set in order to determine the suitable dosage of CRU on cotton. The special purpose was to provide evidence for the CRU application in cotton fields. The results show that the application of CRU promotes the growth of cotton significantly and enhances the nitrogen supply in the whole period. Compared to the treatment with total N as base fertilizer (UB), the bod, flower, little bolls and total bolls are increased significantly. There are no significant differences in the yield between the CRU treatment and the treatment of controlled release urea and urea combined application (60%CRU + 40%U), but an increase by 12.38%-22.67% compared to the UB treatment, and an increase by 4.49%-7.23% compared to the treatments of total N split application (UD). The nitrogen uptake of CRU treatment was significantly increased by 13.01%-48.32% and 30.27%-13.01% than UB treatment and UD treatment, respectively. The nutrient recovery efficiency of CRU treatment is increased by 16.42-20.59, 5.92-11.29 and 4.22-12.59 percentage points compared to the UB treatment, UD treatment and 60%CRU + 40%U treatment, respectively. In this study, there was a good linearity relationship between the cotton yield and amount of CRU in Wuxue site. The yield of cotton response to amount of CRU could be described by the model of linear plus plateau in Jingzhou site.

Biochar and slow-releasing nitrogen fertilizers improved growth, nitrogen use, yield, and fiber quality of cotton under arid climatic conditions

“…This slow release of N corresponded well and might substantially be supported in the fast development of roots and leaves due to more production of chlorophyll content resulting in higher biomass accumulation and ultimately higher plant height and peak LAI (Silvertooth et al 2011 ; Geng et al 2016 ). Moreover, improved plant height and peak LAI might be because of maximum canopy development which resulted in maximum net photosynthetic rate and assimilate portioning and ultimately higher plant height and peak leaf area index (Wang, 2013 ; Tian et al 2017 ). Several studies have reported that plant height and LAI increase with the application of slow-release N fertilizers in cotton production (Li et al 2007 ; Geng et al 2016 ).…”

Cumulative release characteristics of controlled-release nitrogen and potassium fertilizers and their effects on soil fertility, and cotton growth

“…Using of CRFs may considerably reduce the energy consumption and time required to grow crops because the nutrients are slowly and gradually released throughout the growing season, hence, only one application is needed. Also consumption of natural gas and waste produced by the fertilizer industry can be reduced because of the more efficient use of nutrients23. However, the use of CRFs is still limited compared with the large amount of more conventional fertilizers applied throughout the world.…”

“…Recently, considerable research has been devoted to studying the effects of CRUs and CRKs on cotton production. For example, application of CRU has been found to enhance the nitrogen supply throughout the cotton growing season thus promoting crop growth2. CRU application not only increased nitrogen use efficiencies and crop yields but also reduced the labor costs and risks to the environment22.…”