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Climate variability affects the phenological, physiological, and morphological adaptability of Kiwifruit. Hence, five Kiwifruit varieties were evaluated under variable rainfed climatic conditions in Pothowar. Phenological data of all five varieties was observed at both study sites, including bud initiation, bud swelling, and bud burst. Goldflesh (GDF) and Green Flesh 1 (GF1) were observed to be late in bud burst and to have poor physio-morphological responses and plant survival rates. In contrast, Hayward (H), Bruno (B), and Greenflesh 2 (GF2) exhibited superior performance in terms of plant physiological and morphological traits (e.g., heat damage percentage, photosynthetic activity, shoot length, t runk diameter, d isease incidence percentage, and survival rate). Greenflesh 2 (GF2) plants at both study locations exhibited a lower percentage of heat damage (4.25 and 5.83) than Greenflesh 1 (6.2 and 9.87) and Goldflesh (6.11 and 8.83), respectively. Bruno had more photosynthetic activity (627.31 and 773.5 mol m-2 sec-1) than Goldflesh (330.49 and 343.71 mol m-2 sec-1) and Greenflesh 1 (346.96 and 354.25 mol m-2 sec-1, respectively). Hayward (112.56 and 183.44 cm) and Bruno (109.98 and 160.39 cm) had longer shoots compared to Greenflesh 1 (44.23 and 71.26 cm) and Goldflesh (62.49 and 111.16 cm). Bruno (1.02 and 1.6 cm) and Hayward (0.93 and 1.56 cm) had a significantly larger trunk diameter than Greenflesh 1 (0.74 and 1.3 cm) and Goldflesh (0.78 and 1.3 cm), respectively. Hayward, Bruno, and Greenflesh 2 were significantly more resistant to disease incidence (0.27, 0.15, and 0.41) and plant survival was high (80%, 78%, and 79%) in all three varieties at both locations. Bruno and Greenflesh 2 proved to be the most productive varieties under variable climate conditions; thus, their material can be used to develop future Kiwifruit ideotypes in rainfed regions. [ABSTRACT FROM AUTHOR]

Understanding the impact of the warming trend on phenological stages and phases of cotton (Gossypium hirsutum L.) in central and lower Punjab, Pakistan, may assist in optimizing crop management practices to enhance production. This study determined the influence of the thermal trend on cotton phenology from 1980-2015 in 15 selected locations. The results demonstrated that observed phenological stages including sowing (S), emergence (E), anthesis (A) and physiological maturity (M) occurred earlier by, on average, 5.35, 5.08, 2.87 and 1.12 days decade-1, respectively. Phenological phases, sowing anthesis (S-A), anthesis to maturity (A-M) and sowing to maturity (S-M) were reduced by, on average, 2.45, 1.76 and 4.23 days decade-1, respectively. Observed sowing, emergence, anthesis and maturity were negatively correlated with air temperature by, on average, -2.03, -1.93, -1.09 and -0.42 days °C-1, respectively. Observed sowing-anthesis, anthesis to maturity and sowing-maturity were also negatively correlated with temperature by, on average, -0.94, -0.67 and -1.61 days °C-1, respectively. Applying the cropping system model CSM-CROPGRO-Cotton model using a standard variety in all locations indicated that the model-predicted phenology accelerated more due to warming trends than field-observed phenology. However, 30.21% of the harmful influence of the thermal trend was compensated as a result of introducing new cotton cultivars with higher growing degree day (thermal time) requirements. Therefore, new cotton cultivars which have higher thermal times and are high temperature tolerant should be evolved. [ABSTRACT FROM AUTHOR]

• Environmental variability affects grapevine phenology, yield and fruit quality. • STICS was robust and well adaptable to table grape cultivars in new emerging viticulture regions. • Model efficiency (ME) was high for phenology (up to 0.96), yield (0.84) and pruning weight (0.90). • Model predictions may help in planning vineyard operation and selecting suitable cultivar. Plants strongly interact with their environment making phenology a sensitive indicator of climatic variability. Exploring the possibility of early prediction of phenological timings of table grape cultivars has huge socioeconomic benefits for the growers. Various statistical, mechanistic, and theoretical approaches have been used for parameterization of phenology models mainly for wine grapes. The studies on application of process-based models such as STICS (Simulateur mulTIdisciplinaire pour les Cultures Standard) particularly for table grapes and non-traditional viticulture zones are rather limited. The objective of this study was to calibrate the STICS model and evaluate its performance to simulate phenology and yield of four table grape cultivars in Pothwar- a new emerging viticulture zone of south Asia. For this, phenological timings, growth and yield responses were evaluated at two locations (Islamabad and Chakwal) for two consecutive vintages (2019 and 2020). Daily weather data, soil characteristics, genotype and crop specific data were recorded for model calibration. The results indicated a high robustness of the model for simulating table grapes phenology and yield in all cases. The model simulations indicated a satisfactory to high model efficiency (ME) of 0.69 to 0.94 with a prediction variability up to 4 days for growth stages, whereas ME for yield and pruning weight was 0.84 and 0.90, respectively. The model provided an efficient decision support tool (DST) though crucial predictions for viticulture industry. For instance, early maturity (up to 10 days), lesser yield (19–34 %) and pruning weight (19–42 %) for the warmer location (Chakwal) than for the colder Islamabad were simulated by the model with a high skill. The proximity of predicted values to observed values indicates that STICS is powerful tool for predicting vine phenology and yield, thus it provides a valuable insight in timely planning vineyards operations at key growth stages and selecting cultivars with higher yield for sustainable viticulture. [ABSTRACT FROM AUTHOR]

Climate warming is impacting the phenology, growth and productivity of diverse cropping systems at local, regional and global levels. Long-term observed chickpea-mungbean system (CMS) phenological changes were used for the determination of the relationship between crop practices, climate warming and phenology for the making strategies for CMS to minimize negative climate change impacts. Observed thermal trend from sowing to maturity was ranging from 0.82 to 1.15 °C decade−1 for chickpea and 0.64 to 0.97 °C decade−1 for mungbean during 1980–2018. Observed chickpea phenology stages was earlier for mean value of 7.04 (sowing; S), 6.76 (emergence; E), 4.31 (anthesis; A), 2.15 (maturity; M) days decade−1, whereas chickpea phases were decreased averagely 2.73 (S–A), 2.16 (A–M), 4.89 (S–M) days decade−1. Mungbean, 'S' 6.24, 'E' 5.97, 'A' 3.76, and 'M' 2.01 days decade−1 were occurred earlier. Period of mungbean phenology phases were lessened with averaged 2.45 (S–A), 1.76 (S–M) and 4.23 (A–M) days decade−1, respectively. Phenological stages and phases of both crops chickpea and mungbean correlated negatively with rising temperatures at all sites studied. By using CROPGRO-Chickpea and CROPGRO-Legume models for usual chickpea and mungbean cultivars at the sites for 38 years duration indicated that model predicted phenology stages were accelerated with thermal trend more as compared with observed stages. This showed that, during last decades, growing newly evolved cultivars of pulses having more thermal time requirement have significantly offset the increased temperature induced changes in chickpea (33%) and mungbean (20%) phenology. Therefore, for the mitigation of climate warming influences, newly evolved cultivars for CMS must be familiarized that need greater demand for degree days and having higher tolerance to temperature. [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]

• 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]