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Lemon is a prominent citrus fruit that supports regional economies worldwide. Several agronomic and fruit quality attributes are affected by the rootstock selection, thus its selection is essential for a successful grove. This study aims to compare the agronomic and quality attributes of four lemon cultivars (‘Mikrokarpo Messaras’, ‘Nouvel Athos’, ‘Femminello Commune,’ and ‘Zia gara Bianca’) grafted onto three rootstocks (‘Sour Orange’, ‘Yuma Ponderosa lemon’, and ‘Volkameriana’). The yield and rootstock/scion ratio were estimated along with fruit morphological characteristics (size, equatorial, and polar diameter). Internal fruit quality was also estimated (total soluble solids, total acidity, juiciness, ascorbic acid, total phenols, and total antioxidant activity). ‘Volkameriana’ rootstock stood out among the studied rootstocks, as all grafted lemon varieties increased their productivity. Its combination with the Italian cultivar ‘Femminello Commune’ exhibited enhanced tree vigor and tree yield. For all studied cultivars, the use of ‘Volkameriana’ or ‘Yuma Ponderosa lemon’ rootstocks decreased the total soluble content and total acidity, increased the ascorbic acid content, and did not influence the TSS/TA ratio, total phenols or total antioxidant activity. In conclusion, the vigorous ‘Volkameriana’ and ‘Yuma Ponderosa lemon’ rootstocks are a promising replacement for ‘sour orange’. This research provides valuable insights into the potential use of ‘Yuma Ponderosa lemon’ as a rootstock for lemons, as existing literature is rather limited.

Cotton is a precious commodity that offers raw material to the textile industry. This crop is grown in tropical and sub-tropical regions of the world. Abiotic stresses exerts negative impact on cotton production, but water scarcity has the worst impact. It is rising due to current situation, in which global warming is producing a decrease in precipitation while an increase in evapo-transpiration is causing an agricultural drought. Thus, it is a difficult task for cotton breeders to identify cotton lines that can respond to areas with limited water supplies without lowering yields and might be utilized as suitable parents in a breeding program to produce drought-tolerant indices. The primary objective of this research was the estimation of drought tolerance indices in upland cotton under water deficit conditions. For this purpose, fifty accessions of upland cotton were assessed for their ability to tolerate the water stress under three conditions, namely control, 50% FC, and 75% FC. These genotypes showed significant variations based on morpho-physiological and biochemical characteristics. At control conditions, these genotypes exhibited enhanced growth and better performance. Whereas, the behavior of some indices under 75% FC showed less growth as compared to control, while under the 50% FC highly significant reductions were observed among genotypes. The genotypes that are resistant to drought and those that are susceptible were found using the K-means cluster and biplot analysis. In terms of performance, the genotypes namely Cyto-515, CIM-595, FH-142, and IR-3701 exhibited relatively better in all the treatments and low excised leaf water loss, high relative water contents, chlorophyll contents, free proline contents, and peroxidase activity were observed to be useful selection criteria for drought resistance. These identified genotypes namely, Cyto-515, CIM-595, FH-142, and IR-3701 may be grown in water deficit areas of the country to assess their potential, could be used in breeding programs for development of germplasm suitable for water stress conditions.

The intrinsic and extrinsic traits of citrus fruits change throughout their developmental process, and, therefore, to ensure the highest quality, fruit must be harvested at an appropriate stage of maturity. In a 2-year study, mandarin (Citrus reticulata Blanco) cultivars (Kinnow and Feutrell’s Early) grafted on rough lemon (C. jambheri Lush) rootstock were selected to analyze the effect of harvest time on their physicochemical characteristics and antioxidant potential in two consecutive growing seasons in the Multan region of South Pakistan, which has a subtropical climate. Fruits were harvested from commercial citrus groves at intervals of one month (from September to February). The results showed that different maturity stages/harvesting dates have a significant effect on the fruit quality and yield characteristics of mandarin cultivars. An increase in fruit weight, juice content, total soluble solids, ripening index, juice pH, and total sugar content was observed with the advancement of fruit maturity, while juice acidity, antioxidant capacity, total phenolic content, and vitamin C content had a decreasing trend towards fruit maturity. Overall, both cultivars showed similar profiles to the change in fruit quality traits during growth and development, but their amounts showed great variation. Based on the comprehensive consideration, Kinnow attained the maximum fruit quality and yield values from mid-January to February, whilst Feutrell’s Early attained the maximum values of these parameters from mid-December to mid-January, attributing to higher consumer acceptability. This study demonstrated that harvest time plays a key role in controlling the fruit quality and yield of mandarin cultivars. In practice, harvest time should be highly considered for the fresh and processed citrus market and industry.

The present study investigates the comparative effect of pre- and post-storage quarantine heat treatments (hot water treatment (HWT) and vapor heat treatment (VHT)) on the post-harvest performance of the mango fruit cv. ‘Chenab Gold’. The results indicate that the application of HWT at 48 °C for 60 min or VHT at 47 °C for 25 min after 21 days under cold storage enhanced the ethylene production and fruit weight loss, while decreasing fruit firmness and vitamin C content. Noticeably, the post-storage heat treatments ruptured the fruit and destroyed their market value. However, fruit treated with HWT or VHT at harvest exhibited slow weight loss, better skin color, and maintained biochemical attributes as compared to the control when kept under ambient storage conditions. Taken together, the application of hot water before storage has a positive influence on mango fruit quality, while post-storage heat treatment has a devastating impact upon fruit quality and shelf life, cancelling its potential commercial application.

Wizened buds are frequently observed in pear (Pyrus spp.) trees, which greatly reduces the yield. However, little is known about the mechanism of wizened bud formation. Here, we analyzed physiological and transcriptomic differences between normal buds and wizened buds of ‘710’ pear trees. The results indicated that the sorbitol and boron (B) contents, during bud differentiation, were significantly reduced in wizened buds. The microscopic observation and transcriptome analysis revealed that the collapse of the organ structure and cell wall loosening process may have a close relation with wizened bud formation. Moreover, reduced transcript levels of PpyMYB39.1 and its downstream genes (PpyHT1, PpyHT2, PpyPMEI1 and PpyPMEI2) were found in wizened buds. However, the transcript levels of pentose and glucuronate interconversion pathway genes (PpyPME3, PpyPL18.1, PpyPL18.2, PpyPG1 and PpyPG2) and the concentration of pectin-degradation-related enzymes were increased in wizened buds. Correspondingly, the pectin concentration was significantly reduced in wizened buds. Taken together, PpyMYB39.1 may promote pectin degradation and decrease carbohydrate transport by regulating its downstream genes and is supposed to play a vital role in the wizened bud formation resulting from the cell wall loosening process. Our study provides fundamental insights into wizened bud formation and strategies to reduce the wizened bud occurrence in pear trees.