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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]

First report of cucurbit aphid borne yellows virus (CABYV) infecting melon in Pakistan Keywords: RNA virus; CABYV; Coat protein; Melon EN RNA virus CABYV Coat protein Melon 563 564 2 05/29/20 20200501 NES 200501 Melon ( I Cucumis melo i L.) is one of the most important crops in Pakistan and ranked as 4th largest produced with an annual production of 0.54 M tonnes over an area of 0.037 M hectares (GOP [1]). The presence of this potentially destructive virus on melon could be a serious threat to this important crop, and therefore further studies are needed to monitor CABYV disease impact on cucurbits across the country. [Extracted from the article]

The genus Jasminum L., of the family Oleaceae, includes many species occurring in the wild, or cultivated worldwide. A preliminary investigation based on inter-simple sequence repeats (ISSR) was performed to assess the genetic diversity among 28 accessions, representing nine species of Jasminum from various regions, representing a range of altitudes in Pakistan. A total of 21 ISSR primers were used, which produced 570 amplified bands of different sizes, with a mean polymorphic band percentage of 98.26%. The maximum resolving power, polymorphism information content, and index values of the ISSR markers recorded for primers 6, 16, and 19 were 0.40, 12.32, and 24.21, respectively. Based on the data of the ISSR markers, the resulting UPGMA dendrogram with the Jaccard coefficient divided the 28 accessions into two main clades. At the species level, the highest values for Shannon's information index, polymorphism percentage, effective allele number, Nei's genetic variations, and genetic unbiased diversity were found in Jasminum sambac L. and J. humile L., while the lowest were observed in J. mesnyi Hance and J. nitidum Skan. Based on Nei's unbiased genetic identity pairwise population matrix, the maximum identity (0.804) was observed between J. elongatum Willd and J. multiflorum (Burm. f.) Andrews, and the lowest (0.566) between J. nitidum Skan. and J. azoricum L. Molecular variance analysis displayed a genetic variation of 79% among the nine populations. The study was aimed to established genetic diversity in Jasminum species using ISSR markers. With the help of this technique, we were able to establish immense intra- and interspecific diversity across the Jasminum species. [ABSTRACT FROM AUTHOR]

Jasminum L. is the largest genus containing ~200 species found wild mostly in the tropical regions of the world. The comparative palynological study of nine Pakistani Jasminum species with SEM showed zonocolpus, trilobate, and tricolpus pollen types with simple endocolpus apertures which are plesiomorphic and conserved in the Jasminum species. The equatorial pollen view was prolate, subprolate, and perprolate with elliptic, lobate, subcircular whereas polar view was subtriangular in all species. Few characters were specific to some species like heteropolarity in Jasminum grandiflorum and foveolate exine ornamentation with rounded heterobrochate in Jasminum angulare whereas reticulate and angular homobrochate character was common in other species. The UPGMA dendrogram based on qualitative characters did not support the phylogenetic classification of the genus Jasminum as these are highly conserved. The quantitative data showed more variation in some characters whereas few characters showed little or no variation. A greater variation in pollen size was observed among the variants of same species, for example, Jasminum humile showed highly variable polar length and equatorial diameter as compared to other species. Minimum variation was observed in colpus length which divided all species in to two groups. The large lumina were specific to Jasminum nitidum and broader muri was the prominent characteristic of Jasminum angulare. Some species like Jasminum sambac and Jasminum azoricum were unable to develop true pollen due to structural or functional disabilities. So, the quantitative characters of pollen are only suitable for palynological based grouping of Jasminum species but less suitable to infer their evolutionary relationship., (© 2021 Wiley Periodicals LLC.)

Climate change has not only exacerbated abiotic stress, but has also rendered external conditions more feasible for pests to spread and infest citrus fruit. Citrus leafminer (Phyllocnistis citrella) is a potential pest that directly feeds the newly sprouted leaves and twigs of all three spring, summer and autumn flushes. Increasing temperatures in spring and autumn, leafminer accrued more heat units or developmental degree days to accelerate the biological stages of its life-cycle, thereby increasing the pressure of infestation. Present work was conducted at three different environmental conditions in Sargodha, Toba Tek Singh (TTS) and Vehari districts of the Punjab province, Pakistan; all three experimental sites were located in different agro-ecological zones. More infestation was recorded in all three flushes at TTS and Vehari than in Sargodha. Overall, more damage was observed due to higher temperatures in TTS and Vehari than in Sargodha. After May-June heat stress, spontaneous vegetative growth continued from July to November, produced newly spouted tender leaves for feeding the leafminer larvae, and was seen more in TTS and Vehari. Leafminer larva prefers to enter young and tender leaves with a maximum entrance in leaves up to 1 cm 2 in size while observing no entrance above 3 cm 2 of leaf size. Physiological response of leaves primarily attributed to chlorophyll and carotenoid contents, both of which were recorded lower in the mined leaves, thereby reducing leaf photosynthetic activity. Similarly, lower levels of polyphenols and antioxidant activity were also recorded in the mined leaves. The on-tree age of mined leaves of three vegetative flushes of Kinnow plant was also less counted than non-mined leaves. Climate change has affected vegetative phenology and become feasible for pests due to extemporaneous leaf growth, particularly leafminer, and eventually causes economic loss by supplying low carbohydrates either to hanging fruits or next-season crops.