Physiological Screening of Foxtail Millet Genotypes for Water-Use Efficiency and Yield under Rainfed Conditions

Abstract— A field experiment was conducted during kharif 2015 to assess water-use efficiency (WUE) traits and yield potential of foxtail millet (Setaria italica L.) varieties under rainfed conditions. The trial followed a randomized block design with three replications and included nine genotypes Krishnadevaraya, Narasimharaya, Prasad, Sri Lakshmi, SiA 3085, SiA 3156, Suryanandi, SiA 3221 and SiA 3223. Significant genotypic differences were recorded for growth attributes such as plant height, leaf area and dry-matter accumulation at successive growth stages. SiA 3156 attained the greatest plant height, leaf area and leaf-area index at 30 and 60 days after sowing (DAS), while Suryanandi produced the highest dry matter across stages. Water-use efficiency–related traits also varied widely: SiA 3221 expressed the highest specific leaf area (161.2 cm²) and SPAD chlorophyll meter reading (49.4), whereas Narasimharaya maintained the highest relative water content at 30 and 45 DAS. Yield components differed significantly among varieties—Krishnadevaraya produced the maximum tillers per plant (5.44), SiA 3085 registered the greatest test weight (3.20 g) and Suryanandi achieved the highest grain yield (3111 kg ha⁻¹), followed by SiA 3085 (2874 kg ha⁻¹) and Krishnadevaraya (2824 kg ha⁻¹). The lowest grain yield occurred in SiA 3221 (353 kg ha⁻¹). Krishnadevaraya recorded the highest straw yield (6395 kg ha⁻¹), while SiA 3156 showed the greatest harvest index (64.67 %). These findings demonstrate substantial genetic variability for WUE traits and yield, highlighting the potential to identify superior foxtail millet genotypes for rainfed cultivation.