Diversity of soil Allelopathic Actinobacteria in Tiruchirappalli district, Tamilnadu, India

The present study deals with the diversity of paddy field actinobacterial flora in Tiruchirappalli district. Totally 118 actinobacterial colonies were isolated from 12 different paddy fields, among which 45 isolates were morphologically distinct on the basis of spore color, mycelia formation, pigment production and reverse side color formation. Totally 45 actinobacterial isolates were screened for allelopathic activity against Cyperus rotundus. Among them 6 (13.33%) isolates showed maximum growth inhibition and 17 (37.77%) isolates showed minimum inhibition of weed germination. An attempt was made to correlate the actinobacterial diversity and physico-chemical properties of soils which revealed positive relationship with nitrogen, potassium, copper, and phosphorus. Species diversity indexes (H′), species richness (SR) and species evenness (J′) were also studied.