Growth, Yield and Radiation Energy Conversion of Sweet potato Plant under Different Stick Angles and Various Mulch Type in the Papua Highlands 1 Alberth Soplanit 1 Merlin K Rumbarar and 2 Nur Edy Suminarti
1) Assessment Institute for Agricultural Technology of Papua, Indonesia
2) Faculty of Agriculture, Brawijaya University, Malang, Indonesia
Abstract
The low solar radiation intensity and the short irradiation duration are limiting factors for the crop rate growth and dry matter production of sweet potato plants in the Papua highlands. The aim of this study was to obtain the right type of reflector in sweet potato cultivation combined with a stick technique to increase the efficient use of solar radiation energy and plant productivity. Crop growth rate, dry matter production, tuber yields, and radiation energy conversion are monitored during the growth period of Cangkuang variety. Field trials were conducted at height of 1.560 masl from November 2016 to April 2017. The experiment was arranged in a Split Plot Design with three replications. The main plot consisted of Cangkuang variety with 90 degree and 60 degree sticks angle. The subplots were consisted of without mulch, straw mulch, white sand mulch, clear plastic mulch and black silver plastic mulch. The result shows increasing total dry weight, but then slows down when the crop growth rate decreases. The total dry weight at the silver black plastic mulch with a 60 degree stick angle increased by 70.13 % at the age of 70 to 100 DAP and only increased by 17.50 % at the age of 100 to 130 DAP. Conversion efficiency of radiation energy increases for all mulch that used as a reflector, especially for 60 degree stick angle by 32.03 % at the highest yields 34.15 t/ha while for 90 degree stick angles by 27.35 % at the highest yields 29.72 t/ha.
