TAXONOMY Papaya ringspot virus (PRSV) is an aphid-transmitted plant virus belonging to the genus Potyvirus, family Potyviridae, with a positive sense RNA genome. PRSV isolates belong to either one of two major strains, P or W. The P strains infect both papaya and cucurbits whereas the W strains infect only cucurbits. GEOGRAPHICAL DISTRIBUTION PRSV-P is found in all major papaya-growing areas....

Plants that were infested by the wheat stem sawfly emitted significantly increased amounts of the secondary metabolites linalool, linalool oxide, ß-farnesene, ß-caryophyllene, and 4-heptanone in comparison to uninfested plants. Wheat plants parasitized by Fusarium species also have emitted volatiles. The amount of volatiles released varied by infective species of Fusarium and volatile patterns ...

Recent years have instance that there is a invigoration of interest in drug discovery from medicinal plants for the support of health in all parts of the world . This study was designed to examine the in vitro antimicrobial activities of the flowers and leaves methanolic and ethanolic extracts of Chenopodium album L. Chenopodium album Linn. flowers and leaves were collected from East Esfahan, I...

medicinal plants are infected by fungal diseases. a four years survey indicated that, there are various fungal infections in roots and shoots of several medicinal plants that grown in isfahan. lavender (lavandula angustifolia), rosemarry (rosmarinus officinalis) and viper’s bugloss (borago officinalis) plants were infected by fusarium oxysporum and f. solani on roots, showing wilting and eventu...

the search for alternative ways of controlling sericultural pests has led to the investigation of plant sources for naturally occurring compounds which may have insect growth regulatory, feeding deterrency, repellency and confusantcy characteristics. more than 2000 species of the families asteraceae, fabaceae and euphorbiaceae are known that possess some insecticidal activity. plants with insec...

A wide-ranging examination of plastid (pt)DNA sequence homologies within higher plant nuclear genomes (promiscuous DNA) was undertaken. Digestion with methylation-sensitive restriction enzymes and Southern analysis was used to distinguish plastid and nuclear DNA in order to assess the extent of variability of promiscuous sequences within and between plant species. Some species, such as Gossypiu...