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Citrus holds the position of top ranked fruit crop of Pakistan in terms of area and production. 'Kinnow' (Citrus reticulata Blanco) is considered as the trademark of Pakistan's citriculture industry and occupies the share of 95% out of total citrus production in Pakistan. But there is an alarming problem of single rootstock culture. Rough lemon (Citrus jambhiri Lush.) has monopolized the citrus industry in Punjab province. Rough lemon is susceptible to phytophthora and waterlogging. There is an absolute need for substitute rootstock for higher yield and improved fruit quality of Kinnow. A rootstock scion interaction research trial was conducted during 2017 to 2019. Kinnow was grafted on eight rootstocks, i.e. Cox mandarin, Fraser hybrid, Troyer citrange, Cleopatra mandarin, Poncirus trifoliata, Benton, C-35 and Carrizo citrange. Experiment was laid out according to Randomized complete block design (RCBD). Each rootstock was considered as single treatment and replicated thrice. Performance of six year old Kinnow trees grafted on different rootstocks was evaluated on the basis of physicochemical quality attributes of fruits. Data was taken for two consecutive years and average was calculated. Results revealed that rootstocks had a significant role in manipulating the morphological and biochemical quality attributes of Kinnow fruits. Kinnow fruits from the trees grafted on Poncirus trifoliata rootstock showed the maximum fruit diameter (84.03 mm), peel weight (28.99 g), rag weight (87.68 g) and individual fruit weight (221.85 g). Poor performance of Troyer citrange regarding morphological quality parameters was observed. Total soluble solid (TSS) (13.76 °Brix), Vitamin C (69.38 mg/100 ml) and Total antioxidants (72.32 % inhibition) in Kinnow juice were maximum on Fraser hybrid. Carbohydrate analysis of Kinnow juice by HPLC method revealed that concentration of sucrose, fructose and glucose was highest in Fraser hybrid rootstock. Poor performance of Troyer citrange and C-35 rootstocks was recorded regarding all biochemical parameters of Kinnow. It is concluded that physicochemical quality of Kinnow is manipulated by different rootstocks. Poncirus trifoliata and Fraser hybrid rootstocks can be used as alternate rootstocks for citrus industry of Pakistan to substitute the traditional rootstocks like rough lemon and sour orange. [ABSTRACT FROM AUTHOR]

The effect of Aloe vera (ALV) coating was studied on chillies at 10 ± 1°C for 28 days. ALV gel-coated chillies showed reduced weight loss, disease incidence, red chili percentage, respiration rate, electrolyte leakage, hydrogen peroxide, and superoxide anion contents. The ALV coating maintained general acceptance in terms of visual quality and marketability index with higher chlorophyll contents, ascorbic acid contents, total phenolic contents, and total antioxidants. In addition, ascorbate peroxidase, catalase, superoxide dismutase, and peroxidase activities were markedly higher in coated chillies compared to control. The biochemical attributes such as soluble solids content, acidity, sugar: acid ratio, and juice pH were non-significantly affected by ALV application; however, the said attributes were comparatively higher in contrast to control. In conclusion, ALV edible coating could be used as an eco-friendly approach for delaying senescence and maintaining the postharvest quality of green chillies up to 28 days. Practical applications: Green chilies being highly perishable exhibit limited postharvest life with rapid loss of water, shrivelling, wilting, disease incidence, and reduced consumer acceptability. ALV gel coating significantly delayed postharvest senescence, reduced disease spread, maintained higher antioxidant activities of green chilies during cold storage. Therefore, ALV coating [50%] would be the suitable alternative to synthetic preservatives for extending the storage life and conserving the quality of green chilies. [ABSTRACT FROM AUTHOR]

Aloe vera (ALV) with its unique nutritional profile is being used for food, health, and nutraceutical industries globally. Due to its organic nature, ALV gel coating has created lot of interest for exploring its potential in extending the shelf and storage life of fresh produce. ALV gel coating plays imperative role in delaying fruit ripening by lowering ethylene biosynthesis, respiration rate, and internal metabolic activities associated with fruit softening, color development, enzymatic browning, and decay. ALV gel coating reduces the microbial spoilage due to its antifungal properties and maintains visual appearance, firmness, sugar: acid ratio, total antioxidants, and phenolic contents with conserved eating quality. ALV coated fruits and vegetables showed reduced weight loss, superoxide ion (O2-), hydrogen peroxide (H2O2), ion leakage, and soluble solids content and exhibited higher acidity, anthocyanins, ascorbic acid, catalase (CAT), superoxide dismutase (SOD), and ascorbate peroxidase (APX) activities. It also delayed the enzymatic browning by inducing peroxidase (POD) activity during storage. Recent local studies also revealed that ALV gel coating markedly conserved higher consuming quality and extended storage period (>1.34-fold) of different fruits and vegetables. Overall, Aloe vera gel coating alone or in combination with other organic compounds has shown great potential as a food-safe and eco-friendly coating for maintaining the quality of fruits and vegetables over extended period and reducing postharvest losses in the supply chain. Practical applications: ALV gel is a plant-based natural coating of eco-friendly nature. The present review summarizes the updated information of ALV gel coating application, methods of extraction, combinations with other postharvest coatings, and its impact on quality of various fruits and vegetables. It also provides future insights for the development of commercially applicable ALV gel coating protocols through simulation studies. So, being a natural coating, ALV gel has tremendous potential to be used in fruit and vegetable industries around the globe. [ABSTRACT FROM AUTHOR]

Mango is highly valued crop traded worldwide. Fruit fly is serious issue in mango producing countries, and being a quarantine pest, needs specific disinfestation treatments to fruit before export. This study was aimed to assess the effect of hot water quarantine treatment on two commercial mango cultivars for mango export to China. Mature, physically de-sapped mangoes of both cultivars (Sammar Bahisht Chaunsa and Sufaid Chaunsa) were subjected to hot water treatment (HWT; 48°C for 60 min) as obligatory quarantine protocol for export to China and held at simulated air freight conditions (24 ± 2 °C, 80% RH) for six and eight days till ripening, respectively. At eating soft ripe stage, HWT-treated fruits appeared to maintain visual quality, skin colour, and flesh colour, with substantially reduced disease incidence (stem end rot, side and body rot), skin defects and flesh defects, as compared to control. It was noted that HWT-treated fruits had higher marketability index, taste, flavor, slightly increased soluble solid contents, sugar acid ratio and ascorbic acid in both cultivars, respectively. Fruit weight loss, skin shriveling, firmness, flesh texture, aroma, titratable acidity and antioxidant activities were not significantly affected by HWT. However, HWT-treated fruits exhibited higher total phenolics and carotenoid contents as compared to untreated control fruits. Conclusively, hot water quarantine treatment maintained better fruit physical, biochemical quality and marketability index compared to control, and thus can be used effectively at commercial scale for export of both cultivars to China. [ABSTRACT FROM AUTHOR]

The Kinnow is the extensively cultivated variety of citrus fruit and a common name of mandarin (Citrus reticulate L.) in Pakistan. Being a non-climacteric fruit, it keeps low storage life even in cold storage, because some physiochemical changes may lose its quality. The current study was planned to check the efficacy of plant extracts in comparison with commercial fungicide to enhance the storage life of Kinnow mandarin. Findings regarding the comparison of plant extracts and fungicide (Thiabendazole) indicated that 60% Aloe vera extract showed similar results as synthetic fungicide (TBZ) and controlled fruit decay up to 6.25%. The fruits of same treatment also showed better biochemical characteristics of fruit quality after storage of 90 days. The minimum changes in juice weight, TSS, titratable acidity and ascorbic acid were recorded in Aloe vera extract treated fruits. Fruits coated with 60% Aloe vera extract also maintained higher levels of total phenolic (225.7 mg GAE 100g- 1), antioxidant (76.3%) and enzyme activities of catalase (19.1 mg-1 protein), peroxidase (0.80 mg-1 protein), and superoxide dismutase (130.4 mg-1 protein) during storage. It was evaluated that 60% Aloe vera extract proved valuable for long term storage of Kinnow mandarin and to minimize the rotting of fruit during storage and its performance was almost at par to commercial fungicide and maintained the fruit quality related parameters. Hence it can be recommended to overcome the storage issues of Kinnow fruits. [ABSTRACT FROM AUTHOR]

Modified Atmosphere Packaging (MAP) increases the postharvest life of fresh fruits by suppressing metabolic activities with modified in-package atmosphere. This study was aimed to explore the potential benefits of MAP technology combined with low temperature storage in mango cv. 'Samar Bahisht Chaunsa' to extend its shelf life. Physiologically mature mangoes after harvest were de-sapped (0.5% lime solution), dipped in hot water (52±2°C for 5 min) fungicidal (0.5 mL Prochloraz L-1) solution, packed in 5kg cardboard boxes (T1; Biofresh®, T2; Xtend®, T3; Unbagged) and stored at 13°C±1, RH: 85-90% for 7, 14, 21, 28 and 35 days. Following cold storage, fruit were subjected to two different ripening temperatures (32 and 24°C) with a 24 h 100 ppm ethylene treatment. Data related to physical, physiological, biochemical, organoleptic and marketable attributes was collected. Among MAP bags, the desirable atmosphere comprising high CO2 and low O2 concentration was observed in Biofresh® bags. Tolerance of mangoes under elevated CO2 atmospheres and chilling injury (CI) decreased when storage period exceeded more than 14 days with onset of discolouration issues. Overall, bagged fruit had minimum weight loss, CI intensity, shriveling and remained firmer in comparison to control. Maximum peel colour development was observed in fruit stored up to 14 days in Biofresh® bags when ripened at high temperature (32±1°C). Whereas, fruit kept in Xtend® bags and those without MAP only developed acceptable peel colour up to 7 days of cold storage. Fruit kept in Xtend® bags exhibited minimum ethylene levels (ppm) and endured the least loss in weight and firmness but remained mostly green. Bagged fruit had a higher vitamin C content and lower TA in comparison to unbagged fruits. In conclusion, 'Samar Bahisht Chaunsa' stored at 13°C in Biofresh® bag showed better visual appearance, palatability and nutritive values as compared to Xtend® bag and those without MAP. [ABSTRACT FROM AUTHOR]