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Crop growth models can be valuable tools for researchers, academia, extension educators, and policy makers/planners for the evaluation of sustainable and long-term husbandry practices. Determining the optimum sowing window, which can be determined using crop growth models, is imperative under changing climate conditions. Thus, the main objectives herein were to 1) assess the performance of the cropping system model-crop environment resource synthesis-maize model for hybrids and sowing dates in the spring and autumn, and 2) determine the optimum sowing window in 15 districts of Punjab, Pakistan. In the spring experiment, 3 hybrids (P-33M15, M-DK6525, and S-NK8441) were planted in the main plots and then on 5 different sowing dates (January 15th, February 5th, February 25th, March 15th, and April 5th), they were planted in the subplots. In the autumn experiment, 3 hybrids (P-30R50, M-DK6714, and S-NK6621) were planted in the main plots and then on 5 different sowing dates (June 15th, July 5th, July 25th, August 15th, and September 5th), they were planted in the subplots. Model calibration and evaluation results were better in the spring and autumn. Performance of the model was good for the grain yield in the autumn (mean percentage difference (MPD): 7.47% to 8.90%) compared to the spring (MPD: 9.42% to 11.72%). Model evaluation was good for the early sowing dates (January 15th and February 5th) (error range: 6.26% to 9.65%) compared to the delayed dates (February 25th to April 5th) (error range: 9.34 to 14.91%). In the autumn, the model showed better performance for the delayed sowing dates (February 25th and August 15th) (error range: 5.22% to 9.43%) compared to the early dates (June 15th and July 5th) (error range: 8.56% to 11.27%). The model simulated good growth, development, grain yield, and yield components in the spring and autumn and of both 2016 and 2017. For the model application simulation of data over the long-term (1980 to 2017), the optimum sowing window in the spring was January 15th to March 5th and for the autumn it was July 23rd to August 27th for the 15 districts in Punjab, Pakistan. Simulation of the sowing dates for the whole year indicated that the spring was better compared to the autumn for obtaining the maximum grain yield. The results of the model were in line with the recommendations of the agricultural extension department for the sowing window for spring and autumn maize. It is therefore suggested that farmers should complete the sowing of spring and autumn maize within the sowing window to attain a higher yield of maize in arid and semiarid areas of Punjab, Pakistan. [ABSTRACT FROM AUTHOR]

Blue mold caused by Penicillium species is a major fungal disease threatening the viticulture industry in Pakistan, responsible for deteriorating the quality of grapes during handling, transportation, and distribution. Identification-based approaches of Penicillium species provide a better strategy on accurate diagnosis and effective management. In this study, 13 isolates were recovered from symptomatic grape bunches at five main fruit markets of Rawalpindi district, Punjab province. Based on morphological data and multi-loci phylogenetic analysis, the isolates were identified as two distinct species viz. Penicillium expansum (eight isolates) and Penicillium crustosum (five isolates). Meanwhile, the pathogenicity test of Penicillium isolates presented by the inoculation of grape bunches showed various degrees of severity. For improving the fruit quality and eliminating the needs of synthetic fungicides, botanicals such as thyme (Thymus vulgaris L.), fennel (Foeniculum vulgare L.), garlic (Allium sativum L.), ginger (Zingiber officinale L.), and carum (Carum capticum L.) essential oils (EOs) at concentrations of 0.6, 0.9, 1.2, and 1.5 mg/mL were evaluated. In vitro studies indicated that thyme EO showed a highly significant reduction of fungal growth. Furthermore, the experiments related to reducing the decay development and average weight loss percentage of grapes revealed similar findings. Based on the results of this study, it is recommended that thyme EO can be used as an eco-friendly botanical fungicide against Penicillium spp. causing blue mold disease. [ABSTRACT FROM AUTHOR]

This endeavor includes thirty grapes' genotypes grown in northern zones of Punjab, Pakistan to determine similarities and dissimilarities in forty-four morphological traits according to the descriptor "International Plant Genetic Resources Institute (IPGRI)". The relation between the genotypes was determined by principal component analysis (PCA), and similarity was worked out by using cluster analysis. The dendrogram divided the genotypes into two main groups with classes and subclasses. The variation present within the class was up to 81.72% while the difference between classes was 18.28%. The morphological quantitative traits such as bunch length, bunch width, bunch weight, peduncle length, the weight of 10 berries, number of berry in a bunch, berry length, and berry width were in the following range 27.50-11 cm, 13.75-5 cm, 583.56-77.70 g, 6.50-1.55 cm, 53.70-9.70 g, 354-28, 27.37-11.40 mm and 18.06-10.41 mm respectively, which indicated a wide level of diversity in the selected genotypes. Based on phenological attributes, "Regina", "Perlet", and "Early White" were found early maturing genotypes to prevent berry rotting due to monsoon rains at the final stage of ripening. The data generated in this study would be helpful to preserve the existing germplasm and be available for designing future breeding programs. [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]