Agronomic optimization of nitrogen application, planting geometry and harvesting stage for fodder yield and quality in barnyard millet

Abstract

A field experiment was conducted to evaluate the influence of nitrogen levels, planting geometry and harvesting stages on fodder yield and quality of barnyard millet. The treatments included three nitrogen doses (40 kg N ha-1, 60 kg N ha-1 and 80 kg N ha-1), two planting geometries (30 × 10 cm and 22.5 × 10 cm) and two harvesting stages (earhead emergence and physiological maturity). Among the nitrogen levels, 80 kg N ha-1 yielded the maximum green fodder (15.73 t ha-1) and dry fodder (3.97 t ha-1). The closer spacing of 22.5 × 10 cm resulted in markedly higher yield of green fodder (14.99 t ha-1) as well as dry fodder (3.60 t ha-1) compared to the wider spacing of 30 × 10 cm. Harvesting at the ear head emergence stage gave the maximum green fodder (16.26 t ha-1), whereas the dry fodder (3.60 t ha-1) yield was greater when harvested at physiological maturity. Increased nitrogen dose (40–80 kg ha-1) decreased hemicellulose content (24.3–21.5%) and other fibre fractions (ADF, NDF and lignin), while improvement in total digestible nutrients (64.1–70.0%), dry matter digestibility (66.4–70.0%) and protein (crude) content (6.26–7.30%) together with crude protein yield (170–293 kg ha-1) was observed with the higher doses of nitrogen. Early harvesting enhanced crude protein (8.17%), total digestible nutrients and dry matter digestibility, whereas physiological maturity led to higher crude fibre (32.29%), ADF (28.61%), NDF (53.2%) and lignin (3.5%) contents. Planting geometry did not significantly affect fodder quality attributes. The results specified that 80 kg N ha-1 together with harvesting at earhead emergence phase is optimal for obtaining higher fodder yield with better nutritive quality of barnyard millet under rainfed conditions.