Effect of seed-priming methods on nodulation, nutrient uptake and quality in soybean (Glycine max) under bed-sown condition

A experiment was conducted during the rainy (kharif) seasons of 2015 and 2016 at Ludhiana, Punjab, India, to standardize the best seed-priming treatment in relation to symbiotic characters, NPK uptake by seed and straw and quality content of soybean crop [Glycine max (L.) Merr.]. Different methods of priming, viz. hydro-priming, halopriming and hormonal priming, compared to the control (unprimed) were evaluated by soaking seeds for 2 hr duration and at different concentrations such as T₁, unprimed (control); T₂, hydro-priming (water); T₃, halopriming (KNO₃ 5%); T₄, halopriming (KNO₃ 10%); T₅, halopriming (KH₂PO₄ 5%), T₆, halopriming (KH₂PO₄ 10%); T₇, halopriming (KCl 50 ppm); T₈, halopriming (KCl 100 ppm); T₉, hormonal priming (GA₃ 50 ppm); T₁₀, hormonal priming (GA₃ 100 ppm); T₁₁, hormonal priming (cytokinin 50 ppm); and T₁₂, hormonal priming (cytokinin 100 ppm). The seeds treated with 100 ppm GA₃ showed significant increase in root nodules/plant and root nodule dry weight than control, which was statistically similar in result with 100 ppm cytokinin. Similarly, leghaemogobin content in 100 ppm GA₃ treated seeds recorded at par response to 100 ppm cytokinin-treated seed. Nutrient uptake (N, P and K) in seed and straw at harvesting were also higher with 100 ppm GA₃ treatment. Similarly, quality parameters exhibited relatively higher mean performance with hormonal priming of soybean seeds with 100 ppm GA₃.