Yield of lettuce (Lactuca sativa L.) grown in different types of soil under organic soil amendment

Abstract

Physical properties of coarse and fine textured soils do not promote plant growth which affect the yield and quality of plant. Improving the physical property of soils by amending with organic material before planting is required. The objective of this research was to investigate the effect of amending soil types with organic materials on lettuce quality. The experiment was completely randomized design with six treatments. Green oak lettuce was grown in Ban Thon Soil Series, Ao Luek Soil Series and Ranod Soil Series each amended with cow manure and chicken manure. The results revealed that physical and chemical properties of soils for growing lettuce were significantly different, except for mesopore content, available water capacity and soil hydraulic conductivity. The marketable fresh weight, edible fresh weight and edible dry weight of lettuce grown in different soil treatments did not significantly differ, except for Ban Thon Soil Series. All lettuce yields of Ban Thon Soil Series amended with chicken manure treatment were significantly lower than cow manure treatment by 40%, 42% and 31% for marketable fresh weight, edible fresh weight and edible dry weight respectively. Increasing the marketable fresh weight of lettuce increased the edible parts of both fresh weight and dry weight of lettuce. The marketable fresh weight of lettuce grown in Ao Luek soil series tended to be higher than those in Ranod soil series. Therefore, the yield of lettuce grown in different soil types under organic soil amendments was affected by soil and manure properties as controlling availability and balance of soil nutrient. Also, manure application can improve both lettuce yield and soil quality.