Sulphur Status And Its Effects On Growth And Yield Of Soyabean In Some Soils Of Abia State

ABSTRACT

This study was designed to determine the sulphur (S) status of some soils of Abia State, establish the relationship between forms of sulphur and some soil properties. It was also to determine the S sorption characteristics of the soils. A pot experiment was also carried out to determine the effect of sulphur level on soyabean production. The soils were collected to represent the four major soil type in the statc. The pot experiment was laid out in a split plot experiment fitted into Randomized Complete Block Design with four replications. The soil type 0CC111)ie(l the mi1 plot while the sulphur levels were assigned to the sub plots. The results obtained showed that the soils were acidic with ph-I values ranging from 4.30 —6.20. They were sandy and generally how in nutrient in most of the soils. Some physical and chemical properties of the soil correlated significantly (p < 0.05) with sulphur forms especially P. The sorption capacity of the soils differs significantly with parent materials. Adsorption maximum ranged from 953.7 ugg in Isiala— Ngwa to 2065.7 ugg1 in Ntigha. Sulphate extracted by K2 504varied considerably among the soils and increased with increasing amounts of sulphate sorbed. Fraction of added sulphate recovered by the extract depended upon sulphate sorption capacity. The bonding energy 'K' was highest in coastal plain sand and lowest in shale so also was maximum sulphur buffering capacity (MSBC). In the pot experiment soyabean responded significantly to the sulphur level. Grain yield of soyabean in the experiment varied with locations iii the order: Amaeke> Owerrinta > Umudike. Grain yield of the different locations followed the trend: Amaeke had 20.41 t/ha, Bende 6.36 t/ha, Owerrinta 2.36 t/ha and Uniüdike 1.92 t/ha.