Analisis Pengaruh Faktor Cuaca Untuk Prediksi Serangan Organisme Pengganggu Tanaman (OPT) pada Tanaman Bawang

Abstract

Pest and disease are the main factors which cause low onion productivity in Brebes. The aim of this reasearch was to find out the effect of weather parameter and pest predator toward the intensity of pest attack (Spodoptera exigua, Liriomyza sp dan Thrips tabaci) using Correlation, Stepwise Regression and Principal Component Regresion technique in two regions. The intensity of Spodoptera exigua, Liriomyza sp and Thrips tabaci attack were influenced by various weather variables from at least one of the combined data of Tmax, Tmin, RH and rain , one until three weeks before the attack period. The intensity of the Spodoptera exigua’s attack showed significant positive correlation with the intensity of the attack in the previous week and predator, while Tmax, RH and rain showed significant negative relationship. The intensity of the Liriomyza sp’s attack showed a significant negative correlation with Tmax, Tmin, RH and rain. Thrips tabaci particularly showed significant negative correlation with Tmax and Tmin. The regression result using Stepwise method for predicting the intensity of Spodoptera exigua's pest attack in region 1 (Karangbale and Pamulian) and region 2 (Kedungbokor, Larangan and Sitanggal) based on intensity attack data from previous week, the predator and weather elements showed a high R2 value if it is analyzed for each areas, that are 99,7% and 100% and for Lyriomiza sp with the R2 value are 45,9% and 94,8%. Particularly for Thrips tabaci, attack analysis based on weather element got a good value if both areas are combined, that is 39,6%. Used of the data, though the obtained linear regression equation get high values of R 2 but has not shown the consistency of weather influenced between sites, the weather and other physical factors observed were no different. For each region and each pest’s cases, the affected weather elements are different.