EFEKTIVITAS AGEN PENGENDALI HAYATI TRICHODERMA HARZIANUM UNTUK

Abstract

Leaf spot disease is an important disease in tobacco plants which is caused by multiple pathogens, including Cercospora nicotianae, Alternaria alternata, and Phytoptora nicotianae. The controling of the use of chemical pesticides has often been the primary choice for the farmers but the use of chemical pesticides in the field can be the problems. Biological control is the alternative way that can be done without giving the negative impact to the environment, one of them is by using biological agents Trichoderma harzianum. Biological control efforts by using Trichoderma harzianum aims to determine the effect of Trichoderma harzianum application frequency in controling the leaf spot disease. This research method used randomized block design (RAK), which consists of seven treatments and four replications. The treatment given is the control treatment, application of a biocontrol agent Trichoderma harzianum with some different application frequencies, begining from one application frequency to five the application frequency, and the fungicide application is made of mankozeb. Based on the observations it showed that the identification results of the disease caused by the fungus Cercospora nicotianae. Applications of the fourth frequency showed the lowest severity disease which results significantly different when compared by control treatment and pesticide treatment, it showed that the antagonistic fungus Trichoderma harzianum really influence in pressing the growth of pathogens causing leaf spot.