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Cucumber mosaic cucumovirus (CMV) is a known devastating pathogen and menace threat to several important vegetables worldwide including Pakistan. This study was conducted to determine the incidence, distribution and genetic variability of CMV isolates infecting cucurbits and solanaceous vegetables in the Pothwar region of Pakistan, a rich region for vegetable production. Symptomatic leaf and fruit samples were subjected to double antibody sandwich enzyme linked immunosorbent assay (DAS-ELISA) using polyclonal antibodies for CMV. Moreover, it was further characterized by Triple Antibody Sandwich ELISA (TAS-ELISA), molecular assays and genetic recombination. The pathogen was prevalent in all districts and detected in all 10 tested vegetables i.e. cucumber, round gourd, watermelon, melon, pumpkin, bitter gourd, ridge gourd, smooth gourd, chilli and tomato, with an average incidence ranging from 11.85% to 25.89%, with the highest incidence in district Attock (25.17%) followed by Rawalpindi (23.04%), Jhelum (18.57%), Chakwal (18.30%) and Islamabad (14.45%). Cucumber, tomato, watermelon and chilli were found to be most affected by CMV with an average disease incidence (D.I.) of 45.38%, 21.15%, 19.39% and 19.05%, respectively. Capsid protein (CP) cistron nucleotides based In silico restriction and Phylogenetic analyses revealed that among 10 Pakistani CMV under studied isolates; the four viz., AAJAC, AARpCu, AAHAWM and AACCu isolates were grouped as member of CMV subgroup IB and they shared 94.96% identity with each other while rest of the six isolates viz., AARCF, AARwCu, AARTF, AAHAPu, AAICu and AAJABG grouped in to CMV subgroup II with 92.8% identity among themselves. In recombination detection analysis, the Pakistani CMV isolate AAICu (MH119070) was found likely to be a recombinant between the Indian (X89652) and Pakistani (MH119068) isolates with recombinant breakpoints between 370th and 630th nucleotides. Further research is needed to comprehend the economic impact of the virus and breeding programs for screening of resistant genotypes as per recombinant strains and there is also a need to focus on training of farmer communities to manage disease through adaption of resistant cultivars and controlling vector populations. [ABSTRACT FROM AUTHOR]

The present study was carried out to characterize the exotic olive cultivars on morphological as well as phenological basis and to assess their adaptability in Pothwar (Chakwal area) climatic condition of Pakistan. Majority of the parameters indicated significant variability between the cultivars and positive significant correlation were obtained between the parameters. Cultivars Ottobratica and Arbequina could be used for pollination purpose against maximum cultivars due to the longest flowering duration. Maximum fruit set percentage was recorded in cultivar Arbequina (5.49%) while poor fruit set was observed in cultivar Koroneiki (1.15%) with the mean of 2.66 for all cultivars. Maximum yield per plant was obtained from the cultivar Coratina (22kg) while minimum was recorded from the cultivar Leccino (2.5kg) with mean of 10.54kg. It is concluded from the correlation that bold size cultivars like Coratina, Gemlik, Jerboui and Nabali could be recommended for projection of olive industry in Pakistan under the climatic condition of Chakwal as fruit set percentage has positive correlation with fruit weight. The grouping of above mentioned cultivars in bi-plot on the basis of oil percentage, fruit set percentage and yield per tree also confirmed the recommendation of cultivars. Overall the trait of final fruit set percentage showed the greatest variability among all the traits among all the cultivars. Five cultivars included Coratina, Gemlik, Nabali, Picholine and Jerboui were most suitable for oil and yield production under the climatic condition of Pothwar, Pakistan. [ABSTRACT FROM AUTHOR]

Bell pepper (Capsicum annuum) has been in high demand since ever. High quality of fruit and increased yield are desired characters both for the researchers and the growers. The impact of foliar application of chitosan (CHT), Salicylic Acid (SA) and Putrescine (PUT) on fruit yield and physico-chemical characteristics of "Yolo Wonder" bell pepper cultivar was studied for two consecutive years (2012 and 2013). Results indicate application of chitosan (0.5), putrescine (3 mM) and SA (3 mM) increased fruit weight, fruit diameter, and yield as compared to control and other treatments. Fruit firmness was increased in PUT (2 mM, 3 mM) and SA (3 mM) as compared to control. Furthermore, fruit harvested from these treated plants did not affect days to fruit maturity and number of fruits per plant. Higher PUT (3 mM) and SA (3 mM) concentration proved significantly better in reducing disease incidence. Present research proves SA and PUT sprays more effective than CHT for improving fruit physical and chemical characteristics such as fruit size, fruit weight, yield, fruit firmness, and vitamin C content. Finally, the biostimulants used in this study can easily be used to improve yield and quality of bell pepper without compromising the food safety standards. [ABSTRACT FROM AUTHOR]

We have established an efficient protocol for in vitro callogenesis from leaf explants of Troyer citrange (Poncirus trifoliata x Citrus sinensis) and Feutrell's early (C. reticulata x C. sinensis) using modified MS medium enriched with varied concentrations of 2,4-Dichlorophenoxy acetic acid (2,4-D), Naphthalene acetic acid (NAA) and Benzylaminopurine (BAP). Indirect shoot organogenesis was also achieved from leaf derived calli on medium comprising varied concentrations of BAP, Kinetin (KN) and NAA. Best interaction for callus induction was observed by Troyer citrange with modified MS medium containing 0.5 mg L-1 2,4-D, 0.5 mg L-1 NAA and 0.5 mg L-1 BAP, which resulted in 99.66% of leaf segments producing calli within 16.33 days. Morphological differences were also noticed for calli texture and color with different concentrations of 2,4-D, NAA and BAP used. Compact and hard calli were noticed on MS medium with 0.1 mg L-1 NAA and 0.5 mg L-1 BAP however, medium including 1.0 mg L-1 2,4-D, 0.9 mg L-1 NAA and 0.5 mg L-1 BAP resulted in friable and smooth calli by both cultivars. Exuberant shoot regeneration response (65.33%) with an average of 6.2 shoots/calli was recorded on MS medium with 2 mg L-1 BAP and 0.5 mg L-1 NAA by Feutrell's early. Our findings are the pre-requisite for various biotechnological tools like mutation breeding, somaclonal variations, genetic transformation and somatic hybridization which may be helpful in citrus varietal improvement. [ABSTRACT FROM AUTHOR]

Bell pepper is an important vegetable commodity; getting the intention of industry for fresh exports. However, short postharvest life is one of the major limitations. Comprehensive investigations were made for the possibility of extending storage life of bell pepper through UV-C (Shortwave ultraviolet radiations) and different edible coatings. The UV-C and different edible coatings had significant effects on the shelf life of bell pepper (Capsicum annuum) cv. "Royal Wonder" stored at low temperature. UV-C irradiation (3 and 5 min at 254 nm) as well as edible coatings including; Aloe gel (1.5 and 2.5%), cinnamon oil (0.30 and 0.40%) and chitosan (1 and 1.5%) were applied on the fruit of bell pepper cv. "Royal Wonder". The treated fruit was kept in cold storage for 24 days at 8±1°C with 80-85% RH. The fruit samples were analyzed for physical and chemical attributes with an interval of three days. The results indicated that, all the treatments maintained fruit quality and storage life, but UV-C application for 5 min and 1.5% Aloe gel delayed the changes in firmness, titratable acidity (TA), levels of ascorbic acid, soluble solids content (SSC) and fruit color development during storage. Moreover, weight loss, electrolyte leakage and disease incidence was also lowered by these treatments. Postharvest fruit performance indicated that UV-C application for 5 min and 1.5% Aloe gel significantly maintained the quality of pepper as compared to control up to 24 days. [ABSTRACT FROM AUTHOR]

Despite the ample increase in peach growing area, improvement in quality and average yield is still negligible. The influence of foliar application of calcium chloride (CaCl2), putrescine (PUT) and salicylic acid (SA) on fruit yield and physicochemical characteristics of 'Florida King' peach cultivar was evaluated for two consecutive years (2011 and 2012). Results indicated that, application of CaCl2 (1%), PUT (1, 2 and 3 mM) and SA (2 and 3 mM) increased fruit weight, fruit diameter, pulp: stone ratio and yield compared to control. In addition, fruit harvested from these growth elicitors treated trees did not show significant difference in total soluble solids and total sugar contents. All treatments resulted in higher fruit firmness, acidity and ascorbic acid contents than control. Higher calcium treatments proved toxic and significantly increased the calcium level in leaves and fruit. From present work it can be referred that spraying of CaCl2, PUT and SA, significantly affected yield, and physico-chemical characteristics of peach cv. 'Florida King'. These growth elicitors are considered safe chemicals and can be applied to enhance production and improve fruit quality of peach without compromising the food safety standards. [ABSTRACT FROM AUTHOR]