著者・編者Ikeura, Hiroshi
Phongchanmixay, Sengthong
Chomxaythong, Amphone
Bounyavong, Bounson
Khanthavong, Phanthasin
Khanthavong, Thanouphone
Matsumoto, Naruo
Kawamura, Kensuke
Homsengchanh, Laeh
Inkhamseng, Somphone
タイトル（掲載誌）JIRCAS Working Report : Potential and Efficiency of Underused Agricultural and Fishery Resources in Laos
一般注記Most lowland rice fields in Savannakhet Province, the main rice-producing region in Laos, are rainfed and cover both lowlands as well as gradual hilly terrain with sandy soils. The water and nutrient conditions of the lowland rice fields likely vary by location and geological conditions. Additionally, high risk of nutrient leaching from applied fertilizer is expected in such sandy rainfed fields. The objectives of this study are 1) to assess rice yield and water and soil conditions in the rainfed rice fields of Savannakhet Province, 2) to identify the determinants of variation in rice yield, and 3) to evaluate rice plant growth and nutrient leaching under different split chemicalfertilizer application patterns. The rice grain yield varied from 0.6 to 3.6 t ha-1, and the yield in the lower position fields was significantly higher than in the upper position fields. Surface water in the observed fields was mostly maintained above ground level throughout the planting period. Total carbon, total nitrogen, available phosphorus, and exchangeable potassium were extremely low, while the exchangeable calcium and exchangeable magnesium were relatively high. Exchangeable calcium was selected as the highest influential factor to rice grain yield, followed by total carbon. The grain yield from six split fertilization was higher than from three split fertilization (standard) and basal fertilization only. The split fertilization is advantageous in that it supplies nitrogen for panicle initiation and maturing stages in sandy paddy fields.
一次資料へのリンクURLjircas_working_report90-_23-37 （fulltext）
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）
提供元機関・データベース国際農林水産業研究センター : 国際農研機関リポジトリ