Combined effects of silicon and growth regulator on plant growth parameters of maize (Zea mays L.)

Abstract

Abstract A microplot experiment was carried out during rabi 2021-22 at Thoppur village of Virudhunagar district, to examine the impact of silicon sources and growth regulators on plant growth parameters of maize. Basal application of calcium silicate at six different doses and foliar applications of silicic acid (SA), gibberellic acid (GA) and potassium silicate were evaluated at critical phases in maize crop. The results revealed that basal application of 150 kg of calcium silicate / ha + 0.2 % silicic acid at 15 and 45 DAS + 50 ppm GA at 30 and 60 DAS was found to be effective with enhanced plant height of 121.84, 258.33 and 271.74 cm / plant during vegetative, tasseling and harvesting stage. Stem girth (5.48, 8.43 and 8.85 cm / plant), leaf length (49.64 cm, 77.62 cm and 84.37 cm / plant), leaf breadth (5.87, 8.73 and 8.96 cm / plant) were also increased during vegetative, tasseling and harvesting stage. The chlorophyll index was found higher during tasseling stage (55.17) compared to vegetative stage (54.32) in this treatment. Further, the treatment with basal application of 150 kg of calcium silicate / ha + 0.2 % SA + 50 ppm GA improved the yield parameters viz., cob length (25.43 cm), cob girth (19.03), test weight ( 41.84 g), number of grains row cob-1 (15.30), number of grains cob-1 (337), grain yield (7, 287 kg ha-1), stover yield (9.94 t ha-1) and harvest index (73.31 per cent ha-1). The BC ratio observed was higher in the basal application of 75 kg of calcium silicate + 0.2 % SA at 15 and 45 DAS + 50 ppm GA at 30 and 60 DAS (2.54) followed ½ dose of T2 (150 kg) + 0.2 % SA at 15 and 45 DAS + 50 ppm GA at 30 and 60 DAS (T4) (2.51).