Water requirement for cocoa (Theobroma cacao L.) plant and the effect of climate factors on the distribution of the cocoa pod borer attacks (Conopomorpha cramerella Snellen) in North Luwu Regency using Cropwat 8.0

Abstract

The research aims to determine the water requirements level for cocoa plant growth, and study the effect of climate factor on the area of cocoa pod borer attack. The research was conducted from April to July 2019 in Batu Alang Village, Sabbang district, North Luwu Regency, South Sulawesi. The research consisted of two stages ie. Survey (literature study, observations, and interviews) to obtain dataset for climate, soil and cocoa plant growth and desktop study (simulation using Cropwat 8.0) to run the model using dataset previously obtained from the survey. The results show that evapotranspiration of cocoa (ETc) on stage 1 is 106.53, Stage 2 is 114.2, Stage 3 is 106.2, and Stage 4 is 85.1. Based on the ETc and the effective rainfall values in the study sites, water needs of cocoa plants in North Luwu Regency for all growth stages are adequate. The highest attack area of cocoa pod borer of 8332 ha occurred in February attributed to climatic conditions with an average temperature of 27.2 °C, 81% humidity, and 308 mm rainfall. On the other hand, the lowest attack area was 3224 ha in May that can be attributed to an average air temperature of 27.4 °C, 83% humidity, and 384 mm rainfall. Some climate factors do not have significant influence on the development and the widespread of the cocoa pod borer attacks.