Interference with sex expression, estimation of yield and bioactive compounds in bitter gourd under PGRs-induced conditions

Abstract

Abstract Background The bitter gourd fruit yields are not at a desirable level due to maleness. Maleness is one of the biggest difficulties with bitter gourd, reducing fruit yields substantially. On the other hand, plant stages are the most important consideration for PGR application because of their sensitive responsiveness. Therefore, it is necessary to determine how bitter gourd plants respond to plant growth regulators, namely PGR0 (control: application of water as control treatment), PGR1 (GA3-Gibberellic acid, 100 mgL−1), PGR2 (NAA-Naphthalene acetic acid, 100 mgL−1), and PGR3 (MH- Maleic hydrazide, 100 mgL−1) at three application phases, S1: soaking of seeds; S2: four-leaf; and S3: flower bud in terms of vegetative development, male–female flower sex alteration, and fruit features including bioactive compounds. Results Physiological, floral and yield characteristics of bitter gourd exposed significant changes by GA3 and MH at various stages. The number of leaves plant−1, the fresh mass of the plant, and the fresh mass of fruit and fruit dry matter content were enhanced remarkably for MH application at the seed soaking stage except for plant height and the number of branches plant−1. MH increased the number of female flowers plant−1, the number of fruits plant−1 and the yield at the 4-leaf stage of application. PGRs substantially influenced the quantity of sugar, chlorophyll, total carotenoids, protein, and water content at various phases of their application but not on ascorbic acid, TSS, or total phenol concentration. Conclusions For sex expression and yield attributes, 100 mgL−1 MH at the 4-leaf stage would be effective in bitter gourd. Exogenous NAA showed a considerable dual influence on plant development and antioxidant enzyme activity in bitter gourd fruits.