Enhancing Sustainable Cassava Production in Hilly Areas of Van Yen, Yen Bai Province, Vietnam

Abstract

Low awareness on sustainable production and farming techniques are major factors limiting cassava (Manihot esculenta Crantz) production in the northern mountainous region of Vietnam. In 2011, three experiments were conducted in Van Yen District of Yen Bai province, Vietnam, to determine the appropriate plant density (a control at 10,000 plants.ha-1, high stocking at 12,500 plants.ha-1 and extra-high stocking at 14,000 plants.ha-1), the proper NPK+S fertilizer level (low at 800 kg.ha-1, a control at 1,000 kg.ha-1, a high level at 1,200 kg.ha-1 and an extra-high level at 1,400 kg.ha-1), as well as incorporating the study of a suitable cassava intercropping system for controlling soil erosion. The high density and high fertilizer levels signifi cantly increased the fresh root yield, harvest index, root dry matter and starch content compared to those of the control. However, these parameters were not different at both the extra-high density and extra-high fertilizer levels from those of the high density and high fertilizer levels. In addition, there were no signifi cant differences in the sprouting percentage, the stem diameter with increased stocking and the fertilizer level. It was found that cassava intercropped with peanut, using Tephrosia candida hedgerows, not only considerably increased the plant height, fresh root yield, harvest index, root dry matter and starch content, but also effectively decreased the dry soil loss compared to mono-cropping.