PJB-2011-398
RELATIONSHIP OF PLANT AVAILABLE SULPHUR WITH SOIL CHARACTERISTICS, RAINFALL AND YIELD LEVELS OF OILSEED CROPS IN POTHWAR PAKISTAN
RIZWAN KHALID1, KHALID SAIFULLAH KHAN1*, ZAHID AKRAM2, RAHMATULLAH QURESHI3 AND MUHAMMAD GULFRAZ4
Abstract
A study was carried out in order to assess the status of plant available S in the 15 rain-fed arable soils of Pothwar, Pakistan and to evaluate its relationships with soil characteristics, rainfall distribution and yield levels of oilseed crops in the region. The contents of plant available S (0.01 M CaCl2 extractable SO4-2-S) in the soils varied from 5.7 to 21.7 µg g-1 soil (mean 11.7 µg g-1 soil) and corresponded to 7.0 to 13.8% of the total S in the soils. The adsorbed S contents ranged from 1.9 to 7.8 µg g-1 soil (mean 4.8µg g-1 soil) forming 2.0 to 7.3% of the total S in the soils. The organic S contents ranged from 68.4 to 140.4 µg g-1 soil (mean 97.0 µg g-1 soil) accounting for 81.5 to 89.3% of the total S in the soils. The 0.01 M CaCl2 extractable SO4-2-S was highly significant positive correlated with total S and organic S in the soils. Significant positive relationships also existed between 0.01 M CaCl2 extractable SO4-2-S and the clay, ECe, organic C, total N, and extractable P contents in the soils. Significant negative relationships of 0.01 M CaCl2 extractable SO4-2-S were observed with the CaCO3 and pHs of the soils. Among the climatic factors, 0.01 M CaCl2 extractable SO4-2-S showed significant positive correlation with the mean annual temperature, while the significant negative relationships with rainfall from July to August, total annual rainfall and the rainfall from September to June. A strong positive relationship existed between 0.01 M CaCl2 extractable SO4-2-S contents and the average yield level of oilseed crops (r = 0.80**). Among different crops, groundnut yield had highly significant correlation (r = 0.90**) with the CaCl2 extractable SO4-2-S followed by the sunflower (r = 0.70**), while the rapeseed/ mustard yield had the lowest (r = 0.59*).
To Cite this article:
Download
