Approaches to Cassava Production of Cassava after the Harvest of Rice

Abstract

Prang cassava; cassava is grown in paddy fields after the harvest of rice, usually starts from late October to November (late rainy season), harvested from May to June and has a duration of approximately 5 - 6 months after planting. The cassavas cultivated are Rayong 7, Rayong 72 and Kasetsart 50. Preparation of planting materials is to soak the cassava stakes with chemicals; thiamethoxam (25% WG) or dinotefuran (10% WG)) to prevent pinkish mealy bug (Phenacoccus manihoti),or soaked with organic substances before planting, such as pig manure extract, vermicompost tea,nutrient solution and polysaccharide produced from microorganisms to accelerate root formation and lateral cassava bud emergence during 7-21 days after planting, resulting in clean and pest free seedlings. Vertical planting method produces better root yield than horizontal planting. Soil preparation is done ray plowing the field once using a tractor equipped with 3 or 7 disks and fallowed by making ridges (0.25-0.30 mhigh), so that the soil become loosened and suitable for cassava planning. Cassava is planted immediately on the ridges while the soil moisture content is suitable with the spacing of 0.8 x 0.8 or 0.8 x 1.0 m and cassava yield of 3-4 tons/rai has been reported. The application of inorganic fertilizer having N : P2O5 : K2O rates of 2 : 1 : 2 or 2 : 1 : 3 or 3: 1: 2. This short duration cassava has similar number of storage roots and starch content to the normal harvest one(12 months). The contents of cyanide in leaf and root of this cassava was found to decrease after 5-6 months after planting. Plant growth regulator such as paclobutrazol (PBZ) has been reported to increase the quality of the starch. Decides, growing cassava after rice harvest can reduce the
incidence of root host nematodes, Meloidogyne incognita.