Land optimization using tubers based agroforestry system in Semin, Gunung Kidul

Abstract

Private forest farmers in Semin Village, Semin District, Gunung Kidul Regency transformed the cropping patterns from monoculture to polyculture to meet increasing needs. The farmers planted a variety of food crops to fulfill their short and medium-term needs, and woody plants to meet the long-term needs. Beside this, farmers have processed arrowroot tubers into flour, which can increase household income. The tuber plants apart from being able to live under the shade, have a low glycemic index value so they can be consumed by the diabetics. The method used randomized block design, trials were conducted by cultivating 3 species of tuber plants under the teak shade. Species of tuber plants were arrowroot, canna and yam. The treatments given were: 1) without shade, 2) under 5-year-old teak, 3) under 7-year-old teak. The aim was to understand the relationship between tuber plant growth variables and their environments. Tuber plant growth variables were height and diameter of plant, number of leaves and number of shoot. Environment variables were height and diameter of the teak trees, soil characteristic, and micro climate condition. The relationship was analyzed using linear regression. The results of regression analysis showed that there was a relationship between soil characteristics and plant height (R2=100%), stand height and number of leaves (R2=25.50%), air temperature and number of shoots (R2=22.60%), humidity and the number of shoots (R2=16.70%), light intensity and the number of shoots (R2=14.80%), as well as temperature, humidity, light intensity, percent canopy cover simultaneously and tuber weight/clump (R2=39.10%).