Rice Production Technology Improvements for Higher Productivity Along with the Sustainable Agriculture Process in the Mekong Delta

  This study examines sustainable agricultural development in the Mekong Delta, Vietnam by focusing on technology improvement for minimizing the environmental load in rice production with sufficient yield and quality.  Among rice-producing countries, Vietnam is the third-largest rice export country worldwide. High-yield rice production is still a critical issue in Vietnam. However, in recent years, quality improvement and low environmental load agriculture have been fundamental issues.   In this research, we conducted rice cultivation experiments in 2014, 2015, and 2017 under different conditions of planting density, fertilizer volume, rice variety, use of fertilizer applicator mounted on a transplanter, and use of high-density seedling mat called “Mitsunae.” We conducted 7 seasons with 79 planting patterns in experiments to compare yield, quality, and fertilizer volume in rice production.   As a result of productivity achievement, high-density transplanting does not always produce a high yield. Each performance depends on transplanting density, rice variety, fertilizer volume, or other factors. In general, transplanting machine with a planting width of 25cm achieved a significant yield with short growing duration rice varieties. Those varieties are popular in the Mekong Delta.   We conducted experiments of “high-density seedling mat” called “Mitsunae”, a new nursery technology developed in Japan, to reduce the environmental load and operating costs in rice production. With the “Mitsunae” method, we can reduce the number of rice seedling trays up to three times that of conventional seedling mats. Then, we can minimize the nursery surface area, nursery materials, and total working time, including transplanting time. The “life cycle assessment (LCA)” method is practical for correctly quantifying environmental load reduction. We investigated environmental load reduction caused by “Mitsunae” rice nursery process using LCA method in this research. We could achieve about 20% – 30% reduction of the “greenhouse gas (GHG)” emission volume and economic benefits created by the “Mitsunae” nursery process.