Response of forage sorghum cultivars to different water availability

To explore the effects of varied irrigation regimes on different sorghum [ Sorghum bicolor (L.) Moench] cultivars, a split‐plot experiment adhering to a randomized complete block design with three replications was conducted in 2016 across the Khaveh and Varamin regions. The experimental treatments encompassed irrigation levels as the primary factor and four different sorghum cultivars as the secondary factor. Cultivars exhibiting larger leaf areas were associated with higher chlorophyll content, which enhanced biomass production and the quality of sorghum products. Notable variability in leaf area and crude fiber content was observed across irrigation regimes and cultivars, with 2121 cm 2 to 7153 cm 2 and 40.4% to 50.7%, respectively. Plant height, total dry weight, and water use efficiency were markedly higher under well‐irrigated conditions than those under moderate and severe water deficit conditions. Specifically, the Pegah cultivar displayed the highest leaf area in the Varamin region, measuring 4612 cm 2 and 5911 cm 2 , whereas the Thin Stem cultivar exhibited the lowest leaf area at both locations. Our findings suggest that the Pegah cultivar maintained a high leaf area without reducing total dry weight, indicating its stability across different environments. Therefore, to produce sorghums in similar climatic conditions, full irrigation is recommended. These results underscore the significance of ongoing research and breeding initiatives to leverage genetic diversity and improve sorghum cultivars. Iran faces twin challenges of water stress and food insecurity—challenges that are already pressing and are projected to grow. Yield, quality and quantity, will have to adapt to water shortage and improved water productivity to meet food requirements. An experiment was conducted in two zones of Iran where water scarcity is a major limitation to crop production to determine if limited irrigation regimes may produce high‐yielding forage sorghum with acceptable forage quality. Results of this study indicated that total dry weight and forage quality parameters were significantly influenced by irrigation regimes and cultivars. Increasing water shortage from well‐watered to mild water shortage stress and severe water shortage stress resulted in 19.6% and 39.2% less total dry matter. Crude protein was also higher when applying mild and severe water shortage stress than with the well‐watered irrigation regime, whereas other forage quality parameters did not affect