Effects of Organic Manures and Inoculation on Grwoth an d Yield of Off Season soybean Cultivars Grown on an Acid Soil

Abstract

An off season soybean experiment was carried out during October-December, 1989 at Khon Kaen University to study the effect of organic manures and inoculation upon growth and seed yield of four soybean cultivars. The organic manures used were city garbage compost no. 2 and cattle manure. Each of these was applied at the rates of 0 and 3,750 kg/ha. Inoculation was carried out with the use of Rhizobium japonicum. The plants were grown on an acid Yasothon soil (Oxic Paleustult).
The results showed that shoot, leaf dry weights and leaf areas per plant were affected most by the shortday period. The plants producted only a small amount of shoot growth. There was no differences due to treatment found during the first four harvests but only at the final harvest, the effect due to treament was found i.e. the plants received inoculation and organic manures gave significantly greater shoot, leaf dry weights and leaf areas than those without. Shoot growth was better with city garbage manure than that of the cattle manure. Seed yields were highly related to the total uptake of N in leaves, shoot dry weights, and leaf area duration. Suitable leaf area indes was suggested.