WEEDS DIVERSITY AND ITS IMPACT ON THE EXISTENCE OF MAIN PESTS AND DISEASES IN THEOBROMA CACAO IN TABANAN DISTRICT, BALI PROVINCE INDONESIA

Abstract

Cocoa is one of the plantation commodities which in the last decade has become a source of income for Balinese farmers. However, the current condition of farmers' income from cocoa cultivation has decreased due to several factors including weeds, pest and diseases. This study aims to determine the type and dominance of weeds on cocoa plantations, their impact on cocoa main pests and diseases. The research was carried out by the observation method, namely direct observation of the farmers' cocoa gardens. Weed samples were calculated using the quadratic method, observing the attack of pests was determined by diagonal methods before and after the maintenance of cocoa plants. The results of the study found that there were 10 species of weeds that disrupted cocoa plants in Tabanan regency namely, Cyperusrotundus L, Imperatacylindrica L, Arachniodesaristata (G. Forst) Tindale, Brachiariamutica, Colocasia esculenta L Schott, Crassocephalumcrepidioides, Axonopuscompressus (Swartz) Beauv , Mikania micrantha Kunt, Ageratum conyzoides L, Synedrellanodiflora L. The highest density was found in the S. nodiflora L. type which was 5.73 units / m2, followed by A. conyzoides L. 4.86 units / m2, and C. crepidioideswhich was 4.0 units / m2. The lowest density is found in I. cylindrica L which is 0.86 units / m2. The poorly maintained cocoa plantations, only 30.14% of the potential results that should have been obtained, 31.37% were damaged by Phytophthora palmivora, 21.16% damaged by Helopeltis sp. and 17.33% were damaged by Conophomorpacramerella. Technical improvement in cultivation canincrease potential the results by 62.86% of total cocoa production. Besides that, there was a decrease in the attack of P. palmivora to only 7.84%, Helopeltis sp. 5.70% and C. cramerella 12.5%.