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Decline in soil physical health and crop productivity are the major concerns in wheat-maize cropping system of northwest India. Depending on objective, conservation and deep tillage are the potential solutions. Therefore, a field study was conducted to investigate the interactive effects of land management practices and irrigation regimes on soil properties and wheat-maize productivity. The tillage treatments comprised of no-tillage, strip tillage, conventional tillage and deep tillage, while the irrigation regimes included three levels based on irrigation water over pan evaporation (IW/PAN-E) ratios i.e. I 0.6 , I 0.9 and I 1.2 for both wheat and maize crops. By shattering soil up to 45 cm depth, the deep tillage helped in improving infiltration rate by 31 % over conventional tillage. However, the no-tillage improved soil aggregation by 38 % than deep tillage. At subsurface depth (15-30 cm) the soil bulk density and penetration resistance were found to be significantly lower under deep tillage (1.52 Mg m -3 and 1.9 MPa) than conventional tillage (1.68 Mg m -3 and 2.8 MPa), respectively. The deep tillage enhanced root proliferation by increasing root length density by 44 % and 34 % than conventional tillage in maize and wheat, respectively. The grain yields (Mg ha -1 ) of maize and wheat were 14 % and 12 % more under deep tillage than conventional tillage, respectively. The water productivity varied significantly under different irrigation regimes and was found to be highest at I 0.9 in maize and I 1.2 in wheat.

To investigate the effect of planting methods and irrigation levels on irrigation water productivity and onion (Allium cepa L.) yield, a field experiment was conducted on sandy loam soil at the Research Farm of Department of Soil Science, Punjab Agricultural University, Ludhiana during rabi 2011-12. Three planting methods tested include drip irrigated beds, furrow irrigated beds and flat flood irrigation. In drip irrigated beds and furrow irrigated beds three onion rows were planted on 55 cm wide beds at a spacing of 15 cm from row to row. Three levels of irrigation water were tested i.e. IW/PAN-E ratio of 0.3, 0.4 and 0.5 in drip irrigated onions and 1.2, 1.6 and 2.0 in both bed furrow and flat flood methods of irrigation. The results of the experiment indicated that in drip irrigated beds by applying same quantity and 50 per cent of water as of flat flood irrigation, the yield was increased by 43 and 25 per cent, respectively. Irrespective of irrigation levels, highest onion yield (32.5 t ha -1 ) was recorded under drip irrigated beds followed by furrow irrigated beds (28.5 t ha -1 ) and least under flat flood irrigation method (25.0 t ha -1 ). The onion yield increases with the increase in irrigation level in all the planting methods. The highest irrigation water productivity was observed under drip irrigated beds (1.26 t ha -1 cm) followed by furrow irrigated beds (0.84 t ha -1 cm) and least under flat flood irrigation (0.48 t ha -1 cm) with equivalent IW/PAN-E ratios. Bigger size onions (40 mm and 50 mm) were observed under drip irrigated beds followed by furrow irrigated beds and smallest size bulbs under flat flood method of irrigation. The results revealed that drip irrigation could successfully be used for onion production with significant water saving and higher production.

Tillage alters soil physical properties and impacts soil water regime, crop's relative water content (RWC), and root distribution. Thus, a field study was conducted to characterize and correlate root distribution and assess RWC of corn (Zea mays L.) with soil physical properties under two tillage systems i.e. no-till (NT), and conventional tillage (CT). The RWC, determined four times during a course of the day at two growth stages (V8, i.e. 60 days after planting; and R2, i.e. 90 days after planting), was significantly different (P < 0.05) among two tillage treatments. Corn grown under NT had significantly higher RWC than that under CT during both growth stages. At the V8 growth stage, the RWC ranged from 73.2 to 95.4 % under NT compared with 60.9 to 89.6 % under CT. Further, during the afternoon measurements, RWC was 15 % higher under NT than CT. A similar trend was observed during the R2 growth stage but with lesser RWC values probably due to the lower soil water content at that time. Higher root mass density (RMD) i.e. 0.50 Mg m -3 was measured in 0-10 cm depth under NT than under CT (0.34 Mg m -3 ), and the opposite was true for 10-20 cm depth. Due to the presence of a compacted layer (plow pan) in CT, roots were concentrated mostly in 10-20 cm depth. Further, higher RMD was measured along the row than within row.Keywords: relative water content, corn root distribution, soil water content, moisture stress, no till, conventional tillage Abbreviations CT = conventional tillage; NT = no-till; PR = penetration resistance of soil; RMD = root mass density; RWC = relative water content of leaves.

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