Introduction of new agricultural technology created growing realization of soil physical properties limiting crop production. However, soil physical changes and their impact on crop production are less easily realized because of their exceedingly complex and dynamic nature. Since the nature and arrangement of aggregates in soils could be expected to have a profound influence on pore space, which in turn would govern air and water relations, wide use has been made of aggregate analyses to evaluate spot physical conditions. Experience has sown that it is difficult to interpret these analyses in terms of behaviour on soils. The great difficulty arises from the fact that a given soil permeability can be obtained with an infinity of combinations of different sized aggregates. Rice (Oryza sativa L.) cultivation is due to special conditions of land preparation affect on physical characteristics of soil such as bulk density, infiltration rate, hydraulic conductivity, penetration resistance etc. In this present investigation effect of two establishments viz. direct seeded and manual puddling and three soil moisture regimes viz. on one day after disappearance of ponded water (1DADPW), I2 (3DADPW) and I3 (5 DADPW) on some physical properties of sandy loam soil grown with rice (Oryza sativa L.) c.v. Pant Dhan-12 at four dates viz. D1 (26 May), D2 (10 June), D3 (25 June) and D4 (10 July) during kharif seasons of 2016 and 2017. Results indicated that the magnitude of mean bulk density at surface and sub-surface was found 1.71 and 1.57 Mg m-3 at 30 days after sowing (DAS) and 1.75 and 1.62 Mg m-3 at harvest in direct seeded rice, however in puddled transplanted rice, bulk density was found to be 1.58 and 1.54 Mg m-3 at 30 DAS and 1.61 and 1.56 Mg m-3 at surface and subsurface, respectively. Bulk density increased from surface to sub surface may be due to the presence of fine gravels at the depth. The mean value of hydraulic conductivity (Ks) was observed as 23.63 and 24.23 cm day-1 at 30 DAS and 22.92 and 23.69 cm day-1 at harvest in direct seeded rice. Although in puddled transplanted rice plots Ks was found as 15.62 and 20.21 cm day-1at 30 DAS and 15.25 and 19.60 cm day-1at harvest at surface and subsurface, respectively. Data on infiltration rate (IR) indicated that mean value of IR 32.22 at 30 DAS and 31.16 mm h-1 at harvest in direct seeded and the mean value of IR in puddled transplanted rice it was 29.13 at 30 DAS and 27.55 mm h-1 at harvest at surface and subsurface, respectively. Observations on soil penetration resistance (PR) measurement indicated that the value of PR was found low for direct seeded plots compared with puddled transplanted rice plots. These results clearly indicated that IR and Ks were maximum in direct seeded rice plots compared with the values in puddled rice plots. This study confirmed that puddling can alter the physical properties of soil in rice plots for efficient water management more water can be conserved for optimizing rice yields.

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