Sorghum and pearl millet as sustainable alternative forage options for water limited environments: Opportunities and challenges

Abstract

Forage maize (Zea mays L.,), also referred to as silage maize or fodder maize, is a vital feed crop cultivated for livestock consumption, valued for its high yield potential and nutritional content, making it a staple feed source for ruminant animals like dairy cows, beef cattle, and sheep. Water scarcity poses a significant challenge to livestock feed production, particularly in arid and semi-arid regions, highlighting the urgent need to explore alternative forage crops that are resilient to adverse climatic conditions. Forage sorghum (Sorghum bicolor (L.) Moench) and pearl millet (Pennisetum glaucum (L.) R. Br.) are recognized for their adaptation to drought and heat tolerance, allowing them to achieve high forage yields with lower water requirements compared to maize. In the present chapter, we provide a comparative assessment of the dry matter contents and nutritional compositions of annual forages, including maize, sorghum, and pearl millet, while examining antinutritional compounds such as dhurrin and nitrates and their variations due to genetic, management conditions, and environmental factors. We also discuss the impact of dhurrin and nitrates on health and productivity of livestock. Recommendations for future research are proposed to advance sorghum and pearl millet as alternative forages for water-limited arid and semi-arid agricultural regions globally. By embracing these recommendations, stakeholders can harness sorghum and pearl millet forages as better alternatives to maize in feeding ruminant livestock in water-limited regions, thereby promoting sustainable livestock production and improving food security.