Effect of plant growth regulators and pinching on bud and flower size in Gaillardia

Abstract

The field trial was carried out at College of Horticulture, Dapoli during the Rabi season of 2020-21 to assess the assess the effect of plant growth regulator and pinching on bud and flower size in gaillardia. The experiment was laid out in Factorial Randomized Block Design comprising seven treatments of plant growth regulators (Factor A) coupled with pinching practices (Factor B) and replicated three times. The PGR treatments were T1-Control, T2-Ethephon @ 500 ppm, T3-Ethephon @ 1000 ppm, T4-GA3 @ 100 ppm, T5-GA3 @ 200 ppm, T6-CCC @ 1000 ppm and T7- CCC @ 2000 ppm with pinching each consisting of two levels as P1 - Pinching at 30 days after transplanting and P2 - No pinching. Maximum flower bud length (9.09 mm) was observed in T1 (Control). It was followed by T7 (CCC @ 2000 ppm) 7.48 mm. The lowest flower bud length (6.23 mm) was observed in T2 (Ethephon @ 500 ppm). Largest flower bud (7.44 mm) was observed in P1 (Pinching at 30 DAT) and minimum flower bud length (7.17 mm) was recorded in no- pinching treatment (P1). The interaction effect between plant growth regulator and pinching on average bud length of flower was non-significant. The maximum bud width (16.23 mm) was recorded in treatment T4 (GA3 @ 100 ppm) and was followed by T5 (GA3 @ 200 ppm) 14.76 mm which was at par with Control. The flower bud width was observed minimum (11.78 mm) in the treatment T3 (Ethephon @ 1000 ppm). Maximum flower bud width (14.32 mm) was observed in P1 (Pinching at 30 DAT) and minimum flower bud width (13.53) mm was recorded in P2 (no- pinching treatment). The highest bud width (16.72 mm) was observed in T4P1 (GA3 @ 100 ppm + pinching at 30 DAT). The lowest bud width (11.43 mm) was observed in T3P2 (Ethephon @ 1000 ppm + No-pinching). Significantly maximum flower stalk length (30.53 cm) was observed in the treatment T5 (GA3 @ 200 ppm). The shortest flower stalk length (16.17cm) was recorded in the treatment T3 (Ethephon @ 1000 ppm). Pinching treatment does not significantly influence on flower stalk length. The interaction effect between plant growth regulator and pinching on flower stalk length was also found non-significant. The largest flower diameter (8.23 cm) was recorded in the treatment T7 (CCC @ 2000 ppm) and the least flower diameter (4.26cm) was in GA3 @ 100 ppm treatment (T4). Maximum flower diameter (6.44 cm) was recorded in P1 (pinching at 30 DAT). The shortest flower diameter (6.13 cm) was measured in P2 (no-pinching) treatment. In interaction, maximum flower diameter (8.43 cm) recorded in T7P1 (CCC @ 2000 ppm +pinching at 30 DAT). The minimum flower diameter (4.15 cm) was observed in T4P2 (GA3 @ 100 ppm + no-pinching).