Seed rate and nitrogen application effects on production and brix value of forage sorghum cultivars

Field experiments were carried out during two consecutive years at the National Agricultural Research Centre, Islamabad, with the hypothesis that seed rate and nitrogen (N) application improves plant morphology, yield production and brix value of forage sorghum cultivars. Twenty‐seven treatment combinations comprising three sorghum cultivars, namely, ‘JS–2002,’ ‘Chakwal sorghum’ and ‘JS–263’ were sown with three seed rates (75, 100 and 125 kg ha −1 ) and three N levels (0, 60 and 120 kg ha −1 ). Experiments were laid out in randomized complete block design with split–split plot arrangement in triplicate. Seed rate changed the plant morphology, yield traits and brix value variably. Increasing N application (0–120 kg ha −1 ) had a positive impact on growth and yield traits except brix value. Results revealed that ‘JS–2002’ surpassed the other two cultivars for plant height, number of leaves, leaf area per plant, leaf to stem ratio, green forage yield and dry biomass yield, dry matter content and brix value at given developmental stages at seed rate of 125 kg ha −1 with applied N level of 120 kg ha −1 , during both the years. The highest N application (120 kg ha −1 ) in ‘JS–2002’ gave an increase of 45% forage yield as compared to control.