Studies on the effect of PGPR on the growth and yield of tomato (Lycopersicon esculentum) var. PKM-1

Tomato is one of the most popular and widely grown vegetables in the world, ranking second importance next to potato in many countries. Due to the high usage of N and P inorganic chemical fertilizers in agriculture leads to pollution, acidification of soils and emission of greenhouse gases cause economic and environmental losses. In the present study, isolation and characterization of rhizobacteria such as Pseudomonas sp., Azospirillum sp. and Azotobacter sp. were exanimated from different soils of Cuddalore district of Tamil Nadu. The effect of eight combination treatments of biofertilizers were tested on tomato plant growth and development in pot culture. The results, Pseudomonas sp. was found as highest colony forming unit (6.5×10⁶/g) in Sivapuri village followed by Azotobacter (5.1×10⁶/g) and Azospirillum sp. (4.3×10⁵/g). The highest plant height at different days (25, 50, 75 and 100^th) was found (22.34 cm, 41.71 cm, 65.27 cm and 85.36 cm) with the combination of treatment T₈ (Ps+Azo+Azs) and the highest number of fruits per plant, fruit weight and yield were found in the treatment T₈ (Ps+Azo+Azs) such as 26 (fruits/plant), fruit weight 40.95 (g/fruit) and yield 1040 (g/plant). All the results were found highest compared with control.