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Potato Virus Y has become the most important virus of Potato crop. Various strains of Potato Virus Y has emerged which are affecting the yield of crop and causing economic losses. Due to a conducive climatic conditions for aphid vector the only viable method for control of PVy is identification and cultivation of resistant varieties. Three year's trial was conducted to identify advance lines and varieties showing resistance towards prevalent strains of Potato Virus Y. PVYO, PVYLD and PVYVN were found most virulent and destructive. No line was found resistant, 3 lines showed moderately resistant response, 5 lines were moderately susceptible, 12 lines was susceptible whiles 2 lines shown highly susceptible response. Incidence and Severity of plants were calculated in field trials and climate data including the averages of maximum temperature, minimum temperature, relative humidity and precipitation was compared with disease development in field trials. Increase in maximum temperature had strong positive correlation with disease severity, while relative humidity and precipitation were negatively correlated with disease development. [ABSTRACT FROM AUTHOR]

Twenty Peas (Pisum sativum L.) varieties/lines were evaluated against Fusarium wilt caused by Fusarium oxysporum f. sp. pisi by sowing them in sick plot during the year of 2016-17 at the Plant Pathology Research Institute, Faisalabad. Each cultivar/line was planted in a single row of three meter length, with plant to plant and row to row distances of 15cm and 30 cm respectively and replicated thrice by following Randomized Complete Block Design (RCBD). Out of these twenty varieties/lines 13 including check variety Olympia were found highly susceptible ranging from 53.2 to 83.5% plant mortality. Six varieties/lines were susceptible ranging from 30.3 to 44.1% plant mortality. Only a single variety Garrow performed as moderately resistant by showing 21% plant mortality in the field. Efficacy of five fungicides against Fusarium oxysporum f. sp. pisi, at various concentrations was evaluated in-vitro and significant variations among treatments was observed. In general there was a significant decrease in mycelial growth of the fungus with an increase in concentration of fungicides. Tilt (Propiconazol), Daconil (Chlorothalonil) and Crest (Carbendazim) were the most effective fungicides in inhibiting the growth of the fungus in descending order. The Tilt almost 90% inhibited the growth @ 50µg/ml concentration, Daconil and Crest exhibited intermediate effectiveness. Topsin-M (Thiophanate-methyl) and Score (Difenoconazole) were the least effective fungicides. [ABSTRACT FROM AUTHOR]

The current research was conducted to investigate genetic diversity of Ralstonia solanacearum for comparison of different strains that were collected mainly from Netherlands as well as from Bangladesh, Brazil, Kenya, Egypt, Pakistan and Palma. Forty six strains were included in contemporary studies whereas main biovars for these strains included biovar-2 except GMI1000 that belonged to biovar 3. Genetic diversity of bacterial wilt disease caused by R. solancearum was assessed by focusing mainly on three genes i.e. mutL, cbhA and dps. All the genes seem to be conserved but in case of mutL some strains showed divergence. Multi Locus Sequence Typing (MLST) scheme was used in this contemporary research. It was concluded that polymerized chain reaction (PCR) is the most imperative and appropriate modern tool of molecular biology to find genetic diversity in Ralstonia solanacearum causing bacterial wilt. [ABSTRACT FROM AUTHOR]

Fungitoxic effects of three homeo-fungicides viz; Rigrous, Ventage, Vampire and six methanolic plant extracts viz; Garlic Extract, Ginger Extract, Akk Leaf Extract, Neem Leaf Extract, Moringa Leaf Extract and Parthenium Leaf Extract at nine different concentrations viz; 5, 10, 20, 50, 100, 150, 300, 500 and 1000 μg/ml were tested in vitro by applying poisoned food technique method at an incubation period of nine days at 25 ± 2°C. Mycellial growth of the fungus in response to various homeo-fungicidal at different concentrations was compared Vampire proved to be the best as it has reduced the mycelial colony (83.4 percent) which was followed by Rigrous (82.2 percent), while Vantage proved to be the least effective (76.5 percent) at highest concentration (1000 μg/ml). None of the other homeo-fungicides have completely checked the mycelial growth of F. oxysporum f.sp. pisi. The experiment was arranged in randomized complete design (CRD) However, when growth of the fungus in response to various methanolic plant extracts and their concentrations were compared, Neem leaf extract proved to be the best as it had given the maximum colony reduction (60.5 percent) followed by Ginger extract (57.7 percent), while Parthenium leaf extract proved to be the least effective (25.4 percent) at highest concentration (1000 μg/ml). None of the tested Plant extracts and their concentrations tested has completely checked the mycelial growth. There was an overall trend of reduction in mycellial growth of fungus with an increase in the concentration of homeo-fungicides and methanollic plant extracts. [ABSTRACT FROM AUTHOR]