Pengaruh Status Nutrisi Medium Pada Efektivitas Penghambatan Trichoderma Harzianum Terhadap Sclerotum Rolfsii Secara In Vitro

Trichorderma has been used as biological agent to control diseases in plantation. The agent is commonly applied in a specific formula for technical conciderat ion. To be succcsfull as biological agent, Trichoderma should be viable in the formula. The experiment was aimed to evaluate the influence of nutrition status of medium on the inhibition activity of Trichoderma harzianum compared to fungicide, against Sclerofium rob/ii. The conidia of T harzianum were dissolved in potato dextrose agar (PDA), soil extract agar (SEA) and tap water agar (TWA) with varying concentration of 0, 103, 104 and lO conidia in1-1. The media were then used for antagonistic test against S. rollcii using dual culture method. The results indicated that nutrition status of media affected the growth of both isolates and inhibition activity of Tharzianuï´. PDA containing Ii)` conidia inhibited the pathogen comparable to that by captafol applied at 20.01) ppm in PDA and TWA and applied at 2.01) ppm in SEA. The same concentrat ion ofconidia but in SEA and TWA also had equal inhibition effect compared to 0.20 ppm captafol in SEA and TWA. Keywords: Trichodermaharzumum.Sclerotium medium nutritio