ABSTRACT
A field study was conducted to determine the effect of plant growth promoting rhizobacteria (PGPR) on growth and yield of bitter gourd. Four PGPR strains (Azospirillum, Phosphorous solubilising bacteria, Pseudomonas flourescens and Bacillus subtilis), one commercial organic product (Aishwarya) and non inoculated control were used. The study revealed that seeds inoculated with Azospirillum (basal @ 5 kg ha-1 + 40 days after sowing (DAS) @ 5 kg ha-1) recorded early germination (6.48 days). The maximum vine length (4.42 m) was recorded in basal @ 2 l/plant application of both Bacillus subtilis and Pseudomonas flourescens @ 2.5 kg ha-1. Number of primary branches was maximum (4.80) in plants applied with phosphorous solubilising bacteria (PSB) as basal @ 5 kg/ha and 40 DAS @ 5 kg/ha. Tap root length (23.57 cm) and secondary root length (39.88 cm) were highest in the plants supplied with Azospirillum (basal @ 5 kg ha-1 + 40 DAS @ 5 kg ha-1) where as, dry root weight (4.64 g) was more in case of double application of Bacillus subtilis basal @ 2 l plant -1 + 40 DAS @ 2 l plant -1. Two time application of Bacillus subtilis basal + 40 DAS @ 2 l plant -1 produced the maximum yield plant -1 and yield plot -1 (2.72 kg and 16.33 kg respectively).