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Soil compaction due to field trafficking involves a complex interplay of machinesoil properties. In contrast to previous studies simulating worst field scenarios, this two-year field experiment investigated the effects of traffic-induced compaction involving moderate machine operational specifications (axle load, 3.16 Mg; mean ground contact pressure, 77.5 kPa) and lower field moisture contents (< field capacity) at the time of trafficking on soil physical properties, spatial root distribution, and corresponding maize growth and grain yield in sandy loam soil. Two compaction levels, i.e. two (C2) and six (C6) vehicle passes, were compared with a control (C0). Two maize (Zea mays L.) cultivars, i.e. ZD-958 and XY-335, were used. Results showed topsoil (< 30 cm) compaction with increases in bulk density (BD) and penetration resistance (PR) up to 16.42% and 127.76%, respectively, in the 10-20 cm soil layer in 2017. Field trafficking resulted in a shallower and stronger hardpan. An increased number of traffic passes (C6) aggravated the effects, and the carryover effect was found. Higher BD and PR impaired root proliferation in deeper layers of topsoil (10-30 cm) and promoted shallow horizontal root distribution. However, XY-335, compared with ZD-958, showed deeper root distribution under compaction. Compaction-induced reductions in root biomass and length densities were respectively up to 41% and 36% in 10-20 cm and 58% and 42% in the 20-30 cm soil layer. Consequent yield penalties (7.6%-15.5%) underscore the detriments of compaction, even only in topsoil. In crux, despite their low magnitude, the negative impacts of field trafficking under moderate machine-field conditions after just two years of annual trafficking foreground the challenge of soil compaction. [ABSTRACT FROM AUTHOR]

Crop residue mulch in agricultural systems preserves soil health and improves crop productivity through its moderating influence on soil temperature regime and enhanced moisture retention. Therefore, a field experiment was conducted to determine the changes in soil properties and grain yield of irrigated summer maize in response to wheat straw mulching in the Northern maize region in China. The treatments investigated were: i) application of wheat straw mulch (5000 kg ha-1); and ii) no-mulch application (control). Maize growth and yield attributes were determined during various growth stages, and soil hydro-thermal properties were recorded for two depths (0-15 and 15-30 cm). Straw mulch increased the yield by 18% and also increased total dry biomass yield by 20%, compared to no-mulch. Yield increment was attributed to the increased number of ears per area and kernels number per ear. The effect on thousand kernels weight was found non-significant. Vigorous maize growth was observed under straw mulch treatment, having greater leaf area index, unit leaf rate, leaf area duration, and crop growth rate. Similarly, the dry matter partitioning for maize kernels was greater in mulch treatment. At the late reproductive stages (R3 and R5), SPAD values for ear and below-ear leaves were higher under mulch treatment. Straw mulch decreased the daytime soil temperature by 1.9 and 1.5°C on average for 0-15 and 15-30 cm soil layers, respectively. Whereas, the soil moisture content increased about 2.5% (0-15 cm) and 3% (15-30 cm) under the mulch treatment. In crux, leftover crop residue application as mulch in irrigated maize could be a sustainable agronomic option to increase the crop productivity. [ABSTRACT FROM AUTHOR]

High temperature during May to July is a major hurdle for production of sorghum as fodder in Pakistan, ultimately resulting in a deficit with respect to the demand of meat and milk for increasing population. A field study was conducted to investigate the impact of exogenous application of natural plant growth-promoting substances on forage yield and quality of sorghum. Seed priming and foliar application (alone or in combination) with 1% sorghum water extract (SWE), 3% moringa leaf extract (MLE) and water were applied. Two foliar applications, the first at one month after sowing and the second at 45 days after sowing were carried out. Untreated seeds were used as control. The results indicated that priming and foliar spray performed best in combination as compared to priming or foliar application alone. All MLE applications (priming plus foliar application, priming alone, foliar spray alone) enhanced growth parameters and chlorophyll contents, which ultimately improved forage yield and total dry matter production of sorghum plants. An increase in crude protein and total ash and decrease in crude fiber was also recorded in plants treated with MLE. The results of this study revealed that exogenous application of MLE at 3% concentration (priming plus foliar application, priming alone, foliar spray alone) significantly enhanced the yield through improvement in sorghum growth. [ABSTRACT FROM AUTHOR]

Solar power is a promising alternative energy source for a sustainable environment for developing countries in the Asian continent. The assessment of its sustainability particularly in the South Asian countries necessitates a complete and rigorous statistical investigation. In the current study, we investigate solar energy profile and potential in Pakistan's Sindh province as a case study. Although the electrification of Sindh Province using off-grid solar PV systems is relatively easy and also most convenient, the challenge is to measure the province's capacity of solar power and its economic viability. Results show that the rural areas of Pakistan have sufficient solar irradiance in order to produce power. The suitable inclination angles of solar power modules contain the significant capacity of solar power for electricity production. Finding regarding economic viability shows that an off-grid solar photovoltaic system ensures the electricity at price of PKR 6.87/kWh while this is cheap source of energy as compared to traditional energy source (about 20.79 PKR /kWh). Furthermore, the system of off-grid solar photovoltaic could reduce, 119,000 metric tons of CO2 per year simultaneously it ensure the all remote rural areas implement the off-grid solar energy system. The study provides a useful renewable roadmap for energy in South Asian countries and those presently captivating distant and off-grid regions. [ABSTRACT FROM AUTHOR]