Stem bleeding disease caused by Thielaviopsis paradoxa is one of the major diseases of coconut in almost all the coconut growing regions of Andhra Pradesh. Bioefficacy of native bioagents viz., Trichoderma spp and Pseudomonas fluroscens on stem bleeding pathogen Thielaviopsis paradoxa under in vitro conditions revealed that all the three isolated native Trichoderma spp were found inhibitory to the mycelia growth of Thielaviopsis paradoxa on Potato Dexose Agar media. Maximum percent inhibition of mycelia growth of Thielaviopsis.paradoxa was obtained by Trichoderma viride (69.35%) followed by Pseudomonas fluroscence to 69.32 % as against only 62.90% growth inhibition of Thielaviopsis paradoxa by Trichoderma harzianum. Twelve substrates tested for mass multiplication of biocontrol agents viz., T.viride, T.harzianum and T.hamatum under in vitro conditions noticed that maximum mycelial growth of Trichoderma spp was found on 30% neem cake and 7% neem cake. Evaluation of native biogents under field conditions revealed that among the eleven treatments imposed, maximum decrease in bleeding patch (13.11 cm) was obtained with T8 i.e., basal application of T. harzianum (50 g) + neemcake (5kg)/year) + smearing of talc formulation of T.harzianum paste on stem bleeding patches) closely followed by T7 treatment (11.55 cm) i.e., basal application of T. viride (50 g) + neemcake(5kg)/year) + smearing of talc formulation of T. viride paste on stem bleeding patches) and T9 treatment i.e., basal application of T.hamatum (50 g) + neemcake (5kg)/year) + smearing of talc formulation of T.hamatum paste on stem bleeding patches) with a reduction in perimeter by 11.55cm and 8.51 cm respectively. On the other hand, un treated control palms showed an increase of 2.68 cm of perimeter of the bleeding patch. Thus, soil application of Trichoderma spp. along with neem cake and smearing of Trichoderma spp paste to the stem bleeding patches was effective in controlling the stem bleeding disease under field condition.

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