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Kinnow orchards grown in different agro-ecological regions of Punjab, Pakistan, namely Sargodha, Toba Tek Singh (TTS) and Vehari districts, were selected to assess the effect of climate variables on fruit-bearing patterns. Experiment was laid out in RCBD while selecting identical features Kinnow plants and labeled twigs at analogous canopy positions in all three sites. Temperature was reported higher in TTS and Vehari areas, while relative humidity in Sargodha accounted for different levels of agrometeorological indices by computing more variations in warm districts. Climate variables influenced fruit-bearing habits and vegetative growth trend in all three flushes while recording heavy fruit-bearing plants during on-year and light fruit-bearing in off-year at Vehari. Similarly, three vegetative flushes were recorded unevenly in all three sites due to different fruit-bearing patterns induced by climate variables. Harvesting pattern of orchards began earlier in Sargodha, where maximum orchards were harvested before new flowering to add evenness to fruiting habits during on & off-years. In warm conditions, fruit ripening arrived in the peak of winter and mostly domestic market-driven harvesting resulted in late start of fruit picking with more erratic fruit-bearing habits. Both physiological and pathological fruit drops have been significantly affected by climate variables with a higher degree of physiological drop in warm regions and pathological effects in the humid conditions of Sargodha on heavy fruit-bearing plants. Fruit yield and grading quality were also affected in both seasons by showing more asymmetrical trend in yield and fruit grading in warm areas of TTS and Vehari due to an irregular fruiting pattern compared to Sargodha. From now on, the climate variables of the three sites directly influenced the fruiting patterns, vegetative flushes, fruit drops, yields and grades of Kinnow mandarin. [ABSTRACT FROM AUTHOR]

Climate change is a global phenomenon occurring throughout the world. Greenhouse gases (GHGs) especially carbon dioxide (CO2) considered to be the major culprit to bring these changes. So, carbon (C) sequestration by any mean could be useful to reduce the CO2 level in atmosphere. Turf grasses have the ability to sequester C and minimize the effects of GHGs on the environment. In order to study that how turf grasses can help in C sequestration, Bermuda grass (Cynodon dactylon) was grown both at industrial and urban location and its effect on C storage were assessed by soil and plant analysis. Dry deposition of ammonium and nitrate was maximum at both locations through the year. However wet deposition was highest during the months of high rainfall. It was examined through soil analysis that soil organic matter, soil C and nitrogen in both locations increased after second mowing of grass. However, soil pH 6.68 in urban and 7.00 in industrial area and EC 1.86 dS/m in urban and 1.90 dS/m in industrial area decreased as the grass growth continue. Soil fresh weight (27.6 g) in urban and (27.28 g) industrial area also decreased after first and second mowing of grass. The C levels in plant dry biomass also increased which showed improved ability of plant to uptake C from the soil and store it. Similarly, chlorophyll contents were more in industrial area compared to urban area indicates the positive impact of high C concentration. Whereas stomatal conductance was reduced in high C environment to slow down respiration process. Hence, from present study it can be concluded that the Bermuda grass could be grown in areas with high C concentration in atmosphere for sequestrating C in soil. [ABSTRACT FROM AUTHOR]

Climate change, urbanization and subsequent environmental changes are depleting freshwater resources around the globe. The reuse of domestic, industrial and agricultural wastewater is an alternative approach to freshwater that can be used for irrigation purposes. However, these wastewaters may contain hazardous and toxic elements, such as heavy metals that are hazardous for human health and the environment. Therefore, an experiment was conducted to evaluate the concentration of macro, micro and heavy metals in cucumber irrigated with different resources (tap water, greywater, dairy water and wastewater). The results showed that the use of different irrigation resources has increased the level of macro (sodium (Na), potassium (K), calcium (Ca), magnesium (Mg)), microelements (zinc (Zn), iron (Fe), manganese (Mn)), and heavy metals (copper (Cu), barium (Ba), lead (Pb) and cadmium (Cd)) in cucumber leaves and fruits. However, their levels were in the range that is safe for human health and the environment was as recommended by FAO maximum values of trace elements (Zn, 2.0; Fe 1.0; Mn, 0.2; Cu, 0.2; Pb, 5.0, and Cd, 0.01 mgL−1). Based on observations, it was also revealed that among different irrigation resources, the use of dairy water in cucumber improved its agronomic attributes and maximum plant yield (1191.02 g), while the different irrigation resources showed a non-significant impact on fruit diameter. However, total soluble solid contents (TSS) were more significant in cucumber fruits treated with wastewater (2.26 °brix) followed by dairy water (2.06 °brix), while the least TSS contents (1.57 °brix) were observed in cucumber plants treated with tap water. The significance of non-conventional irrigation water use in agriculture, particularly greenhouse cucumber (Cucumis sativus) production, is discussed. [ABSTRACT FROM AUTHOR]

Highlights • Observed data from ten districts were used to simulate the impact of historical climate warming on the rice-wheat cropping in Punjab, Pakistan. • Reductions in rice and wheat phenological phases were observed due to climate warming. • Cultivars with higher thermal time and high temperature tolerance are recommended for an adaptation to climate warming for the rice-wheat system. Abstract The phenological changes of a long-term observed rice-wheat system (RWS) were used to determine the relationships among management practices, climate change, and crop phenology to devise adaptation strategies for RWS for mitigating the potential impact of climate change. The study comprised of 10 sites of observed and simulated rice-wheat system phenological data for the historical period from 1980 to 2014 in Punjab, Pakistan. The observed climate warming from sowing or/transplanting to maturity ranged from 0.50 to 1.20 °C decade−1 for rice and 0.77 to 1.07 °C decade−1 for wheat. The observed rice phenological stages were advanced by an average of 7.90 (sowing (S)), 6.60 (transplanting (T)), 4.30 (panicle initiation (PI)), 5.00 (anthesis (A)) and 6.40 (maturity (M)) days decade−1, while rice phenological phases were reduced by an average of 1.4 (S-T), 6.40 (T-M), 3.00 (PI-A), 4.70 (PI-M) and 4.10 (A-M) days decade−1. For wheat, sowing (S) and emergence (E) dates were delayed by an average of 9.50 and 1.30 days decade−1, while anthesis (A) (5.30 days decade−1) and maturity (M) (5.40 days decade−1) dates were advanced. The duration of wheat phenological phases was reduced by an average of 5.50 (S-A), 5.70 (S-M) and 4.60 (A-M) days decade−1. The S and E dates were positively correlated with increasing temperature and the A and M dates and phases (S-A, A-M, and S-A) were negatively correlated with increasing temperature for all study locations. Using the CSM-CERES-Rice and CSM-CERES-Wheat models for standard, field-tested cultivars of rice and wheat for all locations for the 35-year period showed that the simulated phenology stages were earlier with climate warming compared to the observed phenology stages. A significant portion of the negative impact of warming on rice (35%) and wheat (21%) was offset by growing new cultivars that had higher thermal time requirements. Thus, to mitigate climate change impacts, new cultivars for RWS should be introduced that require higher growing degree days and have a high temperature tolerance. [ABSTRACT FROM AUTHOR]

Crop production is greatly impacted by growing season duration, which is driven by prevailing environmental conditions (mainly temperature) and agronomic management practices (particularly changes in cultivars and shifts in sowing dates). It is imperative to evaluate the impact of climate change and crop husbandry practices on phenology to devise future management strategies to prepare for climate change. Historical changes in spring and autumn maize phenology were observed in Punjab, Pakistan during 1980–2014. Sowing (S) of spring maize was earlier by an average of 4.6 days decade −1 , while autumn maize ‘S’ and emergence (E) were delayed on average 3.0and 1.9 days decade −1 . Observed anthesis (A) plus maturity (M) dates were earlier by 7.1 and 9.2 days decade −1 and 2.8 and 4.4 days decade −1 for spring and autumn maize, respectively. Similarly, S-A, S-M and A-Mphases were shortened on average by 2.4, 4.6 and 1.9 days decade −1 and 5.5, 7.8 and 2.2 days decade −1 for spring and autumn maize, respectively. The variability in phenological phases of spring and autumn maize had significant correlation,with the increase in temperature during 1980–2014. Employing the CSM-CERES-Maize model using standard hybrid for all locations and years illustrated that model-predicted phenology has accelerated with climate change more than infield-observed phenology. These findings suggest that earlier late sowing and shifts of cultivars requiring high total growing degree day during 1980–2014, have partially mitigated the negative impact of climate change on phenology of both spring and autumn grown maize. [ABSTRACT FROM AUTHOR]

• Potato-based system phenology trends using data of 12 districts in Punjab, Pakistan. • Analyzed observed weather from Pakistan Meteorological Department from 1981 to 2018. • Correlated trend with temperature to analyze how climate affected system phenology. • SUBSTOR model used to isolate warming, management & cultivar effect on phenology. Understanding the influence of thermal trends, crop management practices, and genetics on the crop developmental stages and phases is critical to develop adaptation strategies in the face of warming trends. The specific study objectives were to determine the correlation between observed potato phenology with the trends of rising temperature, and to investigate the impacts of thermal trend, crop management practices, and changes in cultivars using a modeling approach. The study was conducted at 12 sites in Punjab, Pakistan from 1980 to 2018 using phenological observations for both the spring and autumn potato crop. For the stages observed during spring, there was an average advance of 6.2 days decade−1 for sowing, 6.0 for emergence, 3.8 for tuber initiation, and 2.0 for maturity. However, for the stages observed during autumn, there was an average delay of 5.2 days decade−1 for sowing, 5.1 for emergence, 3.3 for tuber initiation, and 2.3 for maturity. The average phase duration decreased on average by 2.4 days decade−1 for sowing to tuber initiation, 1.8 days decade−1 for tuber initiation to maturity for spring, and 4.2 days decade−1 for sowing to maturity. The average autumn phase duration decreased on average by 1.9 days decade−1 for sowing to tuber initiation, 1.0 days decade−1 for tuber initiation to maturity, and 2.9 days decade−1 for sowing to maturity. With respect to the local weather observation, the average air temperature had increased 0.8 °C decade−1 for spring and autumn from 1980 to 2018. The differences in spring and autumn phenology had a statistically significant negative correlation with the increase in temperature from 1980 to 2018. When the CSM-SUBSTOR-Potato model was used for a standard variety across locations and years, the predicted phenological stages, on average, occurred earlier due to increase in temperature from 1980 to 2018, while there was less impact on the observed phenological stages. This indicated that during the last four decade, adaptation strategies such as earlier planting for spring potato, and later planting for autumn, as well as the release of new cultivars that require more thermal time compared to the traditional cultivars have been implemented by growers have compensated for some part of temperature induced warming trends of spring and autumn potato phenology. [ABSTRACT FROM AUTHOR]