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Despite the immense market and growing demand of Pakistani mango, there has been a rapid decrease in the production and export of mango in the last few years. Low yield and poor quality are considered the major limiting factors in export. Therefore, some high yielding good quality exotic mango cultivars were acclimatized in the country and a comprehensive research studies were executed to investigate the yield potential, fruit physico-chemical characters and sensorial aspects. Diverse seventeen commercial and noncommercial indigenous and exotic mango varieties were selected to collect and analyze fruit morphological data under randomized complete block design (RCBD). There was significantly high fruit weight and pulp contents in 'Kensington Pride'. Total soluble solids (TSS) were higher (21.9 B°) in 'Chaunsa', while, titratable acidity (TA) was lowest in 'Lambay Alfansu' and 'Momi-K'. However, reducing sugars (RS) (4.83%), non-reducing sugars (NRS) (16.38%) and total sugars (TS) (21.21%) were significantly high in 'Surkha Burma'. Ascorbic acid contents (AA) were high in 'Momi-K', whereas, total antioxidants (0.68 mM Trolox g-1), total carotenoids (TC) (52.0 µg 100-1) and flavonoids (1.79 µg 100-1) were significantly high in 'Faisalabad Selection'. Faisalabad Selection and 'Surkha Burma' exhibited high score for taste, flavor, texture, aroma and pulp color compared to other indigenous and exotic varieties. It is concluded that 'Faisalabad Selection', 'Surkha Burma' and 'Kensington Pride' among indigenous and exotic varieties, respectively, had potential in commercial trading and can expend the supply window of mango. [ABSTRACT FROM AUTHOR]

Poor fruit quality of young 'Kinnow' mandarin orchards limits its export potential and hence causes significant economic loss to the growers. Plant growth regulators (PGRs) are widely applied in mature citrus trees to improve fruit quality. However, their application in young orchards is scarce. The current study was designed to evaluate the influence of before and after color break (CB) applications of gibberellic acid (GA3) 10 mg L-1, 2, 4 dichlorophenoxy acetic acid (2, 4-D) 10 mg L-1, putrescine (Put) 0.1 mg L-1 and spermine (Spm) 0.1 mg L-1, on fruit quality of young 'Kinnow' orchards, at harvest, after seven days at ambient conditions (20±2°C and 60?65% relative humidity) and after 45 days at cold storage (4±1°C and 75?80% relative humidity). Application of 2, 4-D significantly reduced titratable acidity (TA) and improved TSS:TA ratio. The GA3 reduced fruit colour development and enhanced mass loss (%); Spm reduced juice mass (%) and increased rind mass (%). The GA3 application before CB significantly decreased reducing sugars (%) whereas, after CB application significantly increased rind mass (%) total soluble solids (TSS), total and non reducing sugars (%) in comparison with control. Polyamines (PAs) application after CB significantly reduced juice mass (%) and increased rind mass (%), TSS, total and non-reducing sugars (%). The 2, 4-D application after CB significantly decreased juice mass (%) and increased TSS, total and non reducing sugars (%) in comparison with control. After 45 days of cold storage 2, 4-D application significantly improved reducing sugars while, Put enhanced mass loss (%). In conclusion, 2, 4-D may be applied in young 'Kinnow' mandarin orchards after CB; however, PAs applications may be restricted due to their undesirable effect on fruit quality. [ABSTRACT FROM AUTHOR]

Drought and salinity are causing significant loss in crop yield worldwide. Genetically engineered salt and drought tolerant crop varieties can be a potential remedy for the recovery of lost uncultivated saline and low rain fall areas. In eukaryotes, transcription factors are involved in gene expression which activate or repress the transcription under specific conditions. Hence, the present study has been designed to characterize a fully modified synthetic hsr1 gene. This gene encodes for a transcription factor of heat shock family and has been found to be involved in drought and salinity tolerance in yeast. The synthetic hsr1 gene was cloned under double 35S promoter and caMV terminator for high level of expression in the transgenic plants. Initially the gene was cloned into pJIT163 and then into expression vector pGreen0029. Agrobacterium tumefaciens strain GV was used as a vector for transformation into tobacco. In three different experiments about 34.5% transformation efficiency was observed. Putative transgenic plants were confirmed by PcR analysis using hsr1 gene specific primers. Further screening of these putative transgenic plants against different salinity levels and drought stress showed that transgenic plants were tolerant to drought and salinity conditions. Transformation in the model plant paves the way to genetically engineer vital crops for the development of drought and salinity resistant genotypes. © 2015 Friends Science Publishers [ABSTRACT FROM AUTHOR]

Fruit softening and quality management is very important to reduce postharvest losses in peach. Present study was conducted to observe the effect of harvest location and cultivars on peach fruit softening and quality during ripening at ambient conditions (30±1°C and 60-65% RH). Fruit harvested from Sillanwali exhibited significantly higher ethylene production (24.27 μL C2H4 kg-1 h-1), respiration rate (1.04 mL CO2 kg-1 h-1), ascorbic acid contents (11.11 mg 100 g-1), activities of catalase (CAT; 47.53 U mg protein-1), peroxidase (POD; 32.48 U mg protein-1), endo-polygalacturonase [(endo-PG; 11.61 Δ viscosity (mg protein-1h-1)], exo-polygalacturonase (exo-PG; 138.9 μg gal acid mg protein-1 h-1) enzymes, and significantly lower fruit firmness (25.83 N), ground colour (1.65 score), soluble solid contents (SSC; 11.15 °Brix), total phenolic contents (TPC; 72.28 mg GAE 100g-1), antioxidant scavenging activity (ASA 47.72%), activities of pectin esterase (PE; 1.19 mM NaOH mg protein-1h-1) and endo-1,4-β-D-Glucanase [(EGase; 2.57 Δ viscosity (mg protein-1 h-1)] enzymes as compared to fruit harvested from Soan Valley. Peach cv. "Early Grand" showed significantly higher ethylene production (22.35 μL C2H4 kg-1 h-1), respiration rate (0.85 mL CO2 kg-1 h-1), ASA (59.5%), activities of CAT (49.35 U mg protein-1), endo-PG [(11.43 Δ viscosity (mg protein-1 h-1)] and exo-PG (147.22 μg gal acid mg protein-1 h-1) enzymes, whereas lower fruit firmness (30 N), TPC (108.33 mg GAE 100 g-1), activities of superoxide dismutase (SOD; 27.75 U mg protein-1), PE (1.17 mM NaOH mg protein-1 h-1) and EGase [(2.54 Δ viscosity (mg protein-1 h-1)] enzymes than "Flordaking". In conclusion, harvest locations and cultivars have significant influence on the various physico-chemical attributes including activities of various fruit softening and antioxidative enzymes in peach fruit. [ABSTRACT FROM AUTHOR]

Occurrence of postharvest pericarp browning and rapid decay limit the postharvest storage life of litchi fruit. Effect of low temperature storage on the physico-chemical characteristics of two commercial litchi cultivars 'Bedana' and 'Serai' stored at 5°C for 0, 7, 14, 21 and 28 days were investigated. Incidence of pericarp browning, disease severity and fruit physicochemical characteristics were determined immediately after each removal. During cold storage fruit firmness (15-5.1 N), weight loss (7.06-1.92%), aril: stone ratio (15.3-11.7) and sensory values of fruit decreased, whereas fruit pericarp browning index (0.33-3.25), postharvest disease index (0.5-2.4) and fruit cracking (0.08-1.16%) increased. Fruit weight loss, pericarp browning and disease severity were higher in 'Serai' than 'Bedana' fruit. The fruit of cv. 'Bedana' showed better aril: stone ratio (23.07), firmness (2.1 N), pH (4.15), SSC (19.04%), TA (0.14%), total sugars (12.11%) and ascorbic acid (44.8 mg 100 g-1) contents than 'Serai'. Fruit flavour, texture and aroma changed rapidly during cold storage in 'Serai' than 'Bedana'. The pH of fruit juice showed slightly increasing trend during the whole span of storage, while SSC (20.4-17.4%), TA (0.23-0.05%), ascorbic acid (55-32.8 mg 100g-1), total sugars (13.5-10.5%) and phenolics (0.71-0.45 μg 100 g-1) showed decreasing trend. Litchi cv. 'Bedana' exhibited higher total phenolic contents (0.71 μg 100 g-1) than 'Serai' (0.55 μg 100 g-1). The fruit of cv. 'Bedana' were found superior having less weight loss, pericarp browning index and disease severity index, with higher aril: stone ratio, flavour, texture, aroma, pH, SSC, TA, ascorbic acid, total sugars and phenolic contents. Results suggest that postharvest pericarp browning and fruit quality deterioration can be delayed by cold storage. [ABSTRACT FROM AUTHOR]

Corrugated cardboard boxes are being used for the export of mango fruit worldwide. However, for sea freight, the performance of cardboard box (open vs closed) needs to be evaluated for shipment under low temperature conditions. Under this perspective, two different types of corrugated cardboard box packagings were compared for their effect on the quality, marketability and consumer acceptability in two commercial mango cultivars (Sindhri & Sufaid Chaunsa) of Pakistan under simulated harvest, handling and shipping conditions with storage (11°C; 80-85% RH) intervals of 3, 4 and 5 weeks. Both Sindhri and Sufaid Chaunsa mangoes packed in open top boxes had higher marketability with better firmness and higher sugar contents (less softness score; significant in case of cv. Sufaid Chaunsa only) at ripening as compared to the fruit of closed top boxes. However, the problem of comparatively less peel color development in case of open top packaging needs to be addressed for improving the competitiveness of fruit at retail. Physiological weight loss and rate of respiration were statistically at par in both types of packaging in both cultivars. The low temperature storage duration had significant impact on various physico-chemical and organoleptic fruit quality attributes of both cultivars. Fruit peel color and textural softness were significantly increased with the increase of storage period (from three to five weeks). Moreover, increased weight loss percentage and reduced marketable fruit percentage were observed as the storage/shipping period was extended from three weeks to five weeks. But overall, cv. Sindhri had higher percentage of marketable fruit at all removals due to lower incidence of disease. The trend of disease development was increased in duration of low temperature storage; however, it was less in case of cv. Sindhri, thus indicating its better shipping potential with lower disease incidence as compared to cv. Sufaid Chaunsa. The respiration rate increased with advancement in post shipment ripening stages (i.e., at removal day, after ethylene treatment & at final day of ripening). Overall, open top packaging was found to be more advantageous as compared to closed top packaging, in both cultivars under low temperature storage (11°C; 80-85% RH). More research work is needed for post harvest disease management, particularly in cv. Sufaid Chaunsa, to have commercial success in sea-freighting this cultivar. [ABSTRACT FROM AUTHOR]

Mango fruit quality, marketability and shelflife are adversely affected by postharvest disease development. The fungicides and plant activators suppress the disease development in fruits and vegetables. These studies were targeted to evaluate the potential of pre and postharvest fungicidal applications and on-tree foliar spray of a plant activator viz. a viz. salicylic acid for postharvest disease management in two commercial mango cultivars (Sindhri & Samar Bahisht Chaunsa) of Pakistan. Alternaria alternata (49.3% in Sindhri; 58.5% in Chaunsa), Phomopsis mangiferae (20.0% in Sindhri; 18.2% in Chaunsa) and Botryodiplodia sp. (3.9% in Sindhri; 2.7% in Chaunsa) were found to be associated with mango fruit stem end rot (SER) under agro-ecological conditions of Punjab, Pakistan. Penecillium sp. and Aspergillus sp. (A. niger & A. flavus) were identified to be associated with secondary infections in the diseased mango fruit tissues. Among the postharvest diseases, fruit side rots were predominant (5-10% affected area) followed by stem end and distal end rots (<5% affected area). Postharvest fungicidal treatments gave significantly better disease control as compared to preharvest applications. Postharvest hot water (52°C; 5min) application of Tecto (1.8 mL/L) a.i. Thiabendazole (TBZ) individually and in combination with Sportak (0.5 mL/L) a.i. Prochloraz (tank mix) resulted in significantly lower postharvest disease development than other pre and postharvest treatments. Pre and postharvest fungicidal applications significantly affected fruit peel color development. Relatively better color development was observed in the fruit subjected to postharvest fungicidal treatments as compared to preharvest applications. Non significant effect of both pre and postharvest fungicidal treatments was observed on biochemical quality attributes (TSS & titratable acidity). On tree foliar sprays of salicylic acid (250, 500 & 1000 μM) in cvs. Sindhri and Samar Bahisht Chaunsa at the time of panicle pushing/flower opening, fruit set and stone hardening could not perform well against postharvest disease development. [ABSTRACT FROM AUTHOR]