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Cucumber mosaic virus (CMV) is a tremendous threat to vegetables across the globe, including in Pakistan. The present work was conducted to investigate the genetic variability of CMV isolates infecting pea and spinach vegetables in the Pothwar region of Pakistan. Serological-based surveys during 2016-2017 revealed 31.70% overall CMV disease incidence from pea and spinach crops. Triple-antibody sandwich enzyme-linked immunosorbent assay (TAS-ELISA) revealed that all the positive isolates belong to CMV subgroup II. Two selected cDNA from ELISA-positive samples representing each pea and spinach crops were PCR-amplified (ca.1100 bp) and sequenced corresponding to the CMV CP gene which shared 93.7% nucleotide identity with each other. Both the sequences of CMV pea (AAHAP) and spinach (AARS) isolates from Pakistan were submitted to GenBank as accession nos. MH119071 and MH119073, respectively. BLAST analysis revealed 93.4% sequence identity of AAHAP isolate with SpK (KC763473) from Iran while AARS isolate shared maximum identity (94.5%) with the strain 241 (AJ585519) from Australia and clustered with some reference isolates of CMV subgroup II from UK (Z12818) and USA (AF127976) in a Neighbour-joining phylogenetic reconstruction. A total of 59 polymorphic (segregating) sites (S) with nucleotide diversity (π) of 0.06218 was evident while no INDEL event was observed in Pakistani isolates. The evolutionary distance of Pakistani CMV isolates was recorded as 0.0657 with each other and 0.0574-0.2964 with other CMV isolates reported elsewhere in the world. A frequent gene flow (Fst = 0.30478 <0.33) was observed between Pakistani and earlier reported CMV isolates. In genetic differentiation analysis, the value of three permutation-based statistical tests viz; Z (84.3011), Snn (0.82456), and Ks* (4.04042) were non-significant. The statistical analysis revealed the values 2.02535, 0.01468, and 0.71862 of Tajima's D, Fu, & Li’s F* and D* respectively, demonstrating that the CMV population is under balancing selection.

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Potato crop production is hampered by several fungal, viral, and bacterial diseases. Among the viral Potato leaf roll virus (PLRV), Potato virus Y (PVY), Potato-mop-top-virus (PMTV), Potato virus S (PVS) and Potato virus X (PVX) are the most important. Potato growing fields were surveyed during 2016 and 2017 to determine the incidence of two aphid-borne viruses, PVY and PLRV and to explore the dynamics of potato aphids in four potato-producing district of Azad Jammu & Kashmir (AJK), Pakistan. During survey 930 leaf samples were collected from various locations of Bagh, Sudhnoti, Poonch and Neelum. Parameters determined included aphid population, symptomology, DAC-ELISA based virus incidence, rate of co-infection and disease severity. Overall relative disease incidence of PLRV and PVY was 48.71% and 53.23% respectively. The highest average aphid’s population per field was 390.27 in Sudhnoti due to the low altitude of the surveyed locations. Three aphid species Myzuspersicae Myzusornatusand, Macrosiphum euphorbiaewere identified in AJK potato fields. Themaximum co-infection was recorded from Poonch. It was found that aphid populations decreased with the increase of altitude. The incidence of PLRV and PVY were high where aphid population was high. Therefore, it is necessary to promote awareness among the farmers on virus and aphid symptoms identification and to recommend use of healthy, uncontaminated certified potato seed.