Abstract:
An experiment was conducted in bottle gourd to study the effect of boron and three plant growth regulator (PGR)
viz., gibberellic acid (GA), maleic hydrazide (MH) and ethrel (E) for vegetative, physiological and fruit characters of bottle gourd. Two concentrations of each PGR (50 ppm & 100 ppm) were used for foliar spray at 2 and 4 true leaf stages along with the 12 hours seed soaking by boron (0.05%) in combination with each level of PGRs. The vegetative characters
viz., vine length, number of leaves, number of nodes and inter-nodal length were significantly superior by application of GA
100 (gibberellic acid 100 ppm). Seed soaking of boron (B
1) was also found significant in increasing number of leaves and inter-nodal length on main vine. It reveals that the best treatment combination was B
1GA
100 (boron 0.05% + gibberellic acid 100 ppm) regarding overall vegetative characters. The earliest flower initiation was observed in GA
50 (52.47 days after sowing) and MH
100 (maleic hydrazide 100 ppm) both, while the best combination was B
1MH
100. The first female flower appearance and node number of first flower (male/female) were significantly lowered by E
100 (ethrel 100 ppm) as well as B
1 (boron 0.05% seed treatment) application and the best treatment was B
1MH
100. This combination also gave maximum number of female flower and lowest number of sex-ratio (M/F). Among the fruit characters
viz., fruit maturity, fruit length, fruit diameter, average fruit weight, yield/vine and yield/ha were found significant effect by E
100 and B
1 and best treatment combination was B
1E
100. The number of fruits/vine was observed maximum in B
1GA
100 (4.0) followed by B
1E
100 (3.93) and yield/plant was maximum in B
1E
100 (4.91 kg) followed by B
1GA
100 (4.79 kg). Inter-action effect of PGR and boron was found non-significant for all the characters studied. Based on these observations, it could be suggested that the significant increase in growth, sex-expression and fruit characters would be obtained by the spraying of E
100 at 2 and 4 true leaf stages along with the seed soaking by boron (0.05%) for 12 hours.