Biomass production, water and nitrogen use efficiency in photoperiod-sensitive sorghum in the Texas High Plains
Academic Article
Overview
Research
Identity
Additional Document Info
Other
View All
Overview
abstract
Photoperiod-sensitive sorghum (Sorghum bicolor L. Moench) (PSS) has been identified as a potential bioenergy crop. However, little information is available for water and nitrogen (N) management in PSS in the Texas High Plains. The objectives of this study were to optimize water and N management for improving biomass yield, and to maximize water and N use efficiency in PSS. Two field experiments were conducted at different N rates (experiment I) and irrigation levels (experiment II). In experiment I, biomass yield ranged from 12Mgha-1 to 18Mgha-1 in two years. The optimum N rate and N use efficiency (NUE) were 183kgha-1 and 78kgkg-1 in 2010, and 148kgha-1 and 90kgkg-1 in 2011. In experiment II, biomass yield and evapotranspiration (ET) increased with increasing irrigation, but water use efficiency (WUE) was not affected by irrigation. ET was about 500mm at full irrigation, 360mm at limited irrigation, and 240mm under dryland. Biomass yield ranged from 15Mgha-1 to 23Mgha-1, from 11Mgha-1 to 18Mgha-1, and from 8Mgha-1 to 13Mgha-1 at full and limited irrigation, and under dryland, respectively. WUE ranged from 30kgha-1mm-1 to 47kgha-1mm-1. Biomass yield and WUE varied among years but ET was relatively stable, suggesting higher WUE was due to increased biomass rather than reduced ET. The results of this study indicated PSS may achieve high biomass yield under limited irrigation. 2014 Elsevier Ltd.
