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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]

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]

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]

Pakistan is blessed with a wide range of indigenous mango germplasm. Wild mango genotypes, growing at Azad Jammu and Kashmir (AJK) and its vicinity are valuable resource for unique genetic diversity. The DNA fingerprints of this available germplasm have never been worked out. Hence, the aim of this study was to develop DNA profiles of 31 wild and 13 cultivated genotypes of the country to determine the population structure. Number of alleles per locus of the 51 Simple sequence repeat (SSR) markers ranged from 3 to 9 and a total of 296 alleles with an average of 5.80 alleles per locus. The average polymorphism information content value was 0.764. The expected and observed heterozygosity values were 0.805 and 0.720, respectively, which exhibited high level of genetic diversity in the wild and cultivated mango germplasm. The Bayesian cluster, principal coordinate and hierarchical clustering analyses divided the collected genotypes into three groups i.e. A, B and C. Members of group A and B consisted of wild genotypes entirely, while all commercial genotypes were clustered in group C. The obtained results highlighted genetic diversity encompassed by wild mango genotypes of AJK which can be considered as distinct genotypes for further evaluations in the framework of breeding programs and new cultivar identification in mango. [ABSTRACT FROM AUTHOR]

Mango is the second major fruit crop of Pakistan. A large number of unexplored indigenous mango germplasm with great economic significance is present in the country. Hence, 425 mango accessions were studied from Azad Jammu & Kashmir (AJK) as well as Northern and Southern Punjab to explore the genetic diversity. Total 33 traits (25 qualitative and 8 quantitative) enabled the assessment of morphological and physico-chemical diversity of the studied indigenous mango germplasm. The first three principal components (PCs) contributed 68.06% variability among all mango accessions. The PCs also successfully grouped mango accessions according to their morphological and physico-chemical characteristics. Trunk height, tree circumference, crown diameter, leaf colour, leaf blade length, petiole length, inflorescence length, inflorescence width, fruit shape, fruit weight, soluble solid contents, titratable acidity, sugar:acid ratio, reducing sugars, non-reducing sugars and total sugars were found highly variable. Many of these characters are of substantial economic significance and could be used as breeding goals to increase the germplasm repository as well as fruit yield and quality. In conclusion, morphological and physico-chemical traits were highly useful for mango germplasm characterization. Several accessions also showed potentially good traits which could be used to develop new mango cultivars through future breeding schemes. [ABSTRACT FROM AUTHOR]

'Kinnow' mandarin is an important citrus cultivar, which ranks first among all the fruit crops in Pakistan. Being a nonclimacteric fruit, it has low shelflife even in cold storage, may lose its quality because of some physiochemical changes. Wax coating has been proved as an important strategy to maintain the fruit quality under storage. The present study was planned to compare the different types of waxes which include commercial waxes used by the traders and lab. prepared coatings (PHRC wax and benzaldehyde coating) by the scientists of AARI and UAF, respectively. The results revealed that sharine and paraffin wax exhibited minimum fruit rot (2%) with lower weight loss (11.87%) after 90 days of storage and PHRC wax performed statistically at par to commercial waxes regarding weight loss (12%) and fruit rot (3%). The minimum changes in juice weight, TSS/TA ratio, peel/pulp ratio, ascorbic acid and sugar contents were recorded in coated fruits except benzaldehyde coating. Wax coatings also maintained higher levels of total phenolics (240.7 mg GAE 100g-1), antioxidant (63.4%) and enzyme activities of catalase (17.6), peroxidase (0.71), and superoxide dismutase (137.6 U mg-1 protein) during storage. It is concluded that PHRC wax can be recommended for long term storage of citrus fruits as it performed almost at par to commercial waxes and maintained the fruit quality as well as bioactive juice components. [ABSTRACT FROM AUTHOR]

Trees of citrus cvs 'Lane Late' and 'Valencia Late' oranges were sprayed ten days before anticipated harvest with salicylic acid (SA) at different concentrations (2, 3, 4, 6, 8, 9 mM). Fruits were harvested and stored at 5°C for 93 days to investigate the effects of SA on fruit rot, chilling injury and quality relating parameters such as rind and fruit firmness as well as sugar and organic acid contents. Fruits were analyzed before storage and after 31,62 and 93 days of storage and found that SA at 8 mM and 9 mM reduced fruit rot from 16.93% to 6.06% and 12.78% to 5.12% in 'Lane Late' and 'Valencia Late', respectively. Chilling injury was significantly reduced at 8mM and 9mM treatments. Textural properties relating to rind puncture, rind tensile and fruit firmness forces showed that treated fruits were significantly firmer than those of control. Maintained contents of SSC, TA, individual sugars and organic acids in treated fruit with higher doses after 93 confirmed preliminary findings such as SA has anti-senescent effect. Our research suggests that pre-harvest spray of SA can be used effectively to minimize the postharvest/storage losses of sweet oranges cultivars. [ABSTRACT FROM AUTHOR]

Gladiolus (Gladiolus grandifloras L.), a popular and economically profitable bulbous cut flower, has high demand in both Pakistan domestic and international markets on account of its attractive spikes, florets of huge forms, dazzling colors, varying sizes, and long vase life. However, its quality production is badly affected by non-uniform sprouting, poor crop stand, and old cultivars. To overcome these problems, an experiment was conducted to elucidate the effect of humic acid (HA) applied along with NPK (17:17:17) and five exotic cultivars of gladiolus, 'Eminence', 'Cantate', 'Essential', 'Corveira' and 'Fado', on uniform crop stand, growth, flowering, and quality of cut gladiolus. Among HA treatments, three applications of HA and NPK, applied at planting, 3-leaf, and 6-leaf stages of plant development, followed by two applications of HA and NPK, applied at planting and 3-leaf stage, proved best for early and uniform sprouting, more foliage growth per plant, greater leaf area, and total leaf chlorophyll contents, earlier spike emergence, greater number of florets per spike, longer stems and spikes, and greater diameter of a spike, higher flower quality, longer vase life, higher number of cormels per clump, and greater cormel diameter and weight. Plants grown without HA and NPK application (control) or application of NPK alone, applied at planting, had poor growth, reduced yield, and inferior quality. Among cultivars, 'Fado' performed best for commercial cultivation, considering the applications of HA. [ABSTRACT FROM AUTHOR]