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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]

Fertilization is an effective agronomic management technique for increasing crop production. However, the overuse of chemical fertilizer stimulates energy consumption and greenhouse gas (GHG) emissions, which are antagonistic to sustainable wheat production. In this study, we estimated the energy and GHG performances of different fertilization regimes based on a 32−year fertilization experiment. In this long−term experiment, there are five treatments: CK (no fertilizer with wheat residue removal), NPK (chemical fertilizer with wheat residue removal), NPKPM (chemical fertilizer and pig manure with wheat residue removal), NPKCM (chemical fertilizer and cattle manure with wheat residue removal), and NPKWS (chemical fertilizer with wheat residue retention). The results indicated that NPKCM and NPKPM consumed higher total energy than NPK and NPKWS, which was attributed to the extra energy usage of farmyard manure. Although NPKCM and NPKPM increased energy output by 4.7 and 2.8%, NPKWS stood out by delivering the highest energy use efficiency (EUE) of 6.66, energy productivity of 0.26 kg MJ−1, energy profitability of 5.66, net return of 1799.82 US$ ha−1 and lower specific energy of 3.84 MJ kg−1. Moreover, the yield scale carbon footprint of NPKWS decreased by 66.7 and 52.3% compared with NPKCM and NPKPM, respectively. This study shows that the application of chemical fertilizer in combination with wheat residue retention is a good strategy to increase EUE and economic benefits while decreasing the carbon footprint of wheat production. [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]

A field experiment was conducted to study the forage yield and qualitative traits of different varieties of millet with different days of harvest during the summer, 2014 at Agronomic Research Area, University of Agriculture Faisalabad. Experiment was laid out in randomized complete block design (RCBD) under factorial arrangement having three replications. Pearl millet seeds of three varieties viz. BS-2011, Ghana White and MB-87 were grown in 30 cm apart rows. Net plot size was 3.6 m × 8.0 m. Three different harvesting times were adopted i.e. 55, 65 and 75 days after sowing (DAS). Maximum plant height of pearl millet was recorded for cultivar BS-2011 at harvest time of 75 DAS. Maximum leaf area per plant was observed for the cultivar BS-2011 when it was harvested 75 DAS. Maximum dry matter percentage was also attained in cultivar BS-2011 where plots were harvested at 75 DAS. The highest forage yield was obtained where variety BS-2011 was grown and harvested at 75 DAS. Similarly, maximum dry matter production of BS-2011 was recorded in plots harvested at 75 DAS followed by Ghana White and MB-87 harvested at 55 DAS. Higher crude protein content was recorded where plots were harvested at 55 DAS and cultivar BS-2011 was sown. Higher crude fiber and total ash percentage was also seen in BS-2011. Finally, cultivar BS-2011 proved best for cultivation with harvest time of 75 DAS under Faisalabad conditions to obtain higher forage yield and better quality. [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]

Understanding the actual impacts of climatic warming on winter-sown wheat production will benefit cultivar breeding efforts and agronomic innovations and may help to improve food security. Therefore, we conducted a comprehensive study across the main Chinese winter wheat cropping regions, comprising field warming experiments at four locations and an analysis of 36 years of winter wheat yield data. In the field warming experiments, an increase of 1.0 °C in nighttime temperature enhanced wheat yield by 10.1% on average ( P < 0.05 ). Warming-induced enhancement of 1000-grain weight explained most of these yield increases. Warming shortened the length of pre-flowering phase by 5.4 days, while it prolonged the length of post-flowering phase by 3.8 days. Grain yield increases with warming were similar across experimental sites, even though warming-induced changes in the length of growth periods decreased with increasing ambient temperature. Our analysis of the historical data set was consistent with our field warming experiments; between 1980 and 2015, the major Chinese cropping regions experienced significant warming, especially in daily minimum temperature. Across the historical data set, daily minimum temperature was positively correlated with wheat yield (142.0 kg ha −1 °C −1 ). Our findings are inconsistent with previous reports of yield decreases with warming and may help to inform policy decisions and agronomic innovations of Chinese wheat production to better cope with future climate warming. [ABSTRACT FROM AUTHOR]