Abstract
n Pakistan, the soils are mostly developed from calcareous, alluvial and loessial deposits of late
Pleistocene age located partially on old river terrace and relatively on the channel-levee-remnants,
therefore micronutrients instigate from weathering of rock parent materials and their deficiencies are wide
spread because of intensive cultivation and more nutrient uptake than application. This study was started
to determine the authentic information about boron status of calcareous soils having alkaline pH and low
organic matter (OM) contents under canal and tube well irrigated areas of Punjab. Soil samples were
collected from eighty one sites of five districts of Punjab. Soil samples were analyzed for pHs, texture,
ECe, total N, Extractable K, Olsen P, CaCO3, OM and 0.05 M HCl extractable B. The textural analysis
exhibited that 28 % area had more clay contents and was classified as heavy textured, 42 % had loamy
texture while 30 % had sandy or light textured. The results revealed that more B was observed in clay
textured soils. In case of pH, 83 % area (68 sites) had pH ≥ 8.00 while 13 sites had pH ranged from 7.50
to 8.00 and only one site has pH < 7.50. Incredibly low OM was observed in surveyed area and it was <1
% in all the 81 samples (100 % area was low in OM). Similarly CaCO3 contents were in the range of 2.14
to 9.72 % and about 92 % area surveyed had CaCO3 contents in the range of 3-10 %. The data regarding
B concentration in soil reflected an atrocious depiction of B deficiency in the surveyed soils and exhibited
that out of 81 samples, 66 sites (82 %) had B concentration in the range of 0.10 to 0.45 μg g-1 and were
fall in the deficient range (i.e. <0.50 the critical level) while 12 sites (15 %) having B concentration in the
range of 0.46 to 0.55 μg g-1 and only 3 samples had B range 0.56-0.91 μg g-1. Correlation analysis
exhibited that soil B is positively correlated with OM and clay content of soil while it had strong negative
correlation with CaCO3 content and pH.
