An in vitro effect of agrochemicals on the growth of plant growth promoting rhizobacteria isolated from the soil
Sajid Shaikh, BS Naphade
In the present study effect of four commonly used agrochemicals (2, 4-Dichlorophenoxyacetic acid, Diammonium phosphate, Nitrogen-Phosphorus-Potassium Fertilizer and Urea) was studied on the growth of ten previously isolated PGPR. The herbicide 2, 4- D inhibited the growth of isolate-7 completely at 0.01%. On the other hand isolate-5, 8, 9 and 10 showed growth up to 1% concentration. Isolate 4 was the most tolerant to DAP followed by isolate-5 and isolate-10, Isolate 4 tolerated up to 4% of DAP, While isolate-5 and 10 tolerated 3% DAP. Low concentration was beneficial for the growth of all isolates but growth was inhibited with the increase in concentration of urea. Most of the isolates were inhibited at 4% urea except isolate-10. it was able to grow even at 5% urea. NPK also initially enhance the growth of all isolated but higher concentrations were inhibitory for all isolates. Most tolerant isolates to urea were 4, 7 and 10. They survived up to 3% concentration. Among all isolate-10 was most resistant to all agrochemicals studied.