Performance of Permanent Vegetable Production Systems Designed with the PermVeg Model for the Red River Delta, Vietnam

The aim of the research described was to design permanent vegetable production systems for the Red River Delta in Vietnam. Permanent vegetable production systems better meet the increasing consumer demand for vegetables and may increase farmers’ income. Optimum crop sequences for permanent vegetable production in the Red River Delta were designed with the recently developed model PermVeg. The crop sequences designed were tested in a field experiment from May 2007 to May 2009. The production systems tested were five systems designed according to the scenarios of (i) high profitability, (ii) low labor requirement, (iii) low costs of pesticide use, (iv) high level of crop biodiversity, and (v) low perishable products, respectively. The five systems were compared with the traditional vegetable production system. At local prices, only the high profitability and low labor requirement systems yielded significantly higher profits than the traditional system. At city wholesale market prices, profits of all permanent vegetable production systems were significantly higher than that of the traditional system, except for the low perishability system. Permanent vegetable production systems required more labor than the traditional system. Labor-day incomes of permanent vegetable production systems generally were not higher than those of the traditional system. The labor-day income increased only with the low labor requirement system at city wholesale market prices. The model outcomes correlated reasonably well with the labor requirement and the length in days of production systems in the field. The model poorly predicted profits and costs of pesticide use. We concluded that permanent vegetable production systems can yield higher profits than the traditional system, and can contribute to enhancing employment opportunities and increasing household income.