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The effects of chemical fertilizers on crop growth and grain yield are relatively well-known, but little is known about their synergistic effects with foliar nutrition. The factorial experiment was conducted using a strip-plot design. The main plots consisted of three chemical fertilization treatments at the following rates: N150P105K75, N180P125K90, and N210P145K105. The sub-plots included four combinations of foliar feeding with carbamide [CO(NH2)2], applied at doses of 4.0, 8.0, and 12.0 kg ha−1 at the tillering, booting, and heading stages of winter wheat (WW), respectively. The results indicated that the WW grain production was increased by 21.2% with foliar nutrition applied at a 4:8:12 kg/ha regime under the N180P125K90 chemical fertilization norm compared to the control, exhibiting the highest yield among tested variables. The total grain yield of WW increased with an increase in chemical fertilization norms, providing a significant increase in the fodder yield parameters. Increasing chemical fertilization increased the grain quality indices, but the highest indicators were observed under the moderate (N180P125K90) chemical fertilization norm applied with the foliar nutrition (4.8:12 kg/ha regime). Overall, this innovative farming technique has the potential to limit land degradation and create sustainable farming systems while improving biodiversity conservation and ecosystem services that require less chemical fertilization.

The overarching goal of this paper was to espouse methods and protocols for water productivity mapping (WPM) using high spatial resolution Landsat remote sensing data. In a world where land and water for agriculture are becoming increasingly scarce, growing “more crop per drop†(increasing water productivity) becomes crucial for food security of future generations. The study used time-series Landsat ETM+ data to produce WPMs of irrigated crops, with emphasis on cotton in the Galaba study area in the Syrdarya river basin of Central Asia. The WPM methods and protocols using remote sensing data consisted of: (1) crop productivity (ton/ha) maps (CPMs) involvingcrop type classification, crop yield and biophysical modeling, and extrapolating yield models to larger areas using remotely sensed data; (2) crop water use (m3/ha) maps (WUMs) (or actual seasonal evapotranspiration or actual ET) developed through Simplified Surface Energy Balance (SSEB) model; and (3) water productivity (kg/m3) maps (WPMs) produced by dividing raster layers of CPMs by WUMs. The SSEB model calculated WUMs (actual ET) by multiplying the ET fractionby reference ET. The ETfraction was determined using Landsat thermal imagery by selecting the “hot†pixels (zero ET) and “cold†pixels (maximum ET). The grass reference ET was calculated by FAO Penman-Monteith method using meteorological data. The WPMs for the Galaba study area demonstrated a wide variations (0-0.54 kg/m3) in water productivity of cotton fields with overwhelming proportion (87%) of the area having WP less than 0.30 kg/m3, 11% of the area having WP in range of 0.30-0.36 kg/m3, and only 2% of the area with WP greater than 0.36 kg/m3. These results clearly imply that there are opportunities for significant WP increases in overwhelming proportion of the existing croplands. The areas of low WP are spatially pin-pointed and can be used as focus for WP improvements through better land and water management practices.