Global Climate Indices and Its Effect to Local Rainfall and Productivity of Rainfed Sugarcane (Saccharum officinarum) = Global Climate Indices and Its Effect to Local Rainfall and Productivity of Rainfed Sugarcane (Saccharum officinarum)

다국어 초록 (Multilingual Abstract)

In Indonesia, rainfall is influenced by global climate indices. In relation, the growth of plant, particularly rainfed crops, is influenced by rainfall. Sugarcane plant in Gunungkidul, Yogyakarta, Indonesia usually cultivated in rainfed areas, its productivity much depend on rainfall and climate condition. So, it is necessary to analyze the effects of global climate indices, which is represented by the Southern Oscillation Index (SOI) and Dipole Mode Index (DMI) to local rainfall and productivity of sugarcane plant in the rainfed areas. Research was conducted in Gunungkidul district, one of district in Yogyakarta Province, Indonesia with almost 90% of sugarcane plant is cultivated in rainfed areas. In this study, rainfall and productivity of sugarcane plant data from 2012 to 2016 were used. The effects of SOI and DMI was analyzed on local rainfall, and further more analyzed the effects of local rainfall to productivity of sugarcane plant. At last, stepwise analysis was used to compute the effects of local rainfall in each stage of sugarcane growth to sugarcane productivity. The result shows that global climate indices has significant correlation with rainfall during dry season (June - August) and transisition season (September - November). Stepwise analysis shows that rainfall during the growth of stalk has significant correlation with productivity of sugarcane plant in Nglipar and Karangmojo subdistricts having the coefficient of correlation (R) equal to 0.96 and 0.95, respectively.