BACKGROUND Arctium species (Asteraceae) are distributed worldwide and are used as food and rich sources of secondary metabolites for the pharmaceutical industry, e.g., against avian influenza virus. RNA silencing is an antiviral defense mechanism that detects and destroys virus-derived double-stranded RNA, resulting in accumulation of virus-derived small RNAs (21-24 nucleotides) that can be use...

The terms senescence and programmed cell death (PCD) have led to some confusion. Senescence as visibly observed in, for example, leaf yellowing and petal wilting, has often been taken to be synonymous with the programmed death of the constituent cells. PCD also obviously refers to cells, which show a programme leading to their death. Some scientists noted that leaf yellowing, if it has not gone...

The RNA silencing pathway mediated by small interfering RNAs (siRNAs) plays an important antiviral role in eukaryotes. To counteract this defense barrier, a large number of plant viruses express proteins with RNA silencing suppression activity. Recently, it was reported that the ipomovirus Cucumber vein yellowing virus (CVYV), which lacks the typical silencing suppressor of members of the famil...

Cucumber is a widely grown vegetable crop plant and host to many different pathogens. vein yellowing virus (CVYV) causes economic losses on cucumber crops in Mediterranean countries some part of India such as West Bengal African Sudan. CVYV an RNA potyvirus transmitted mechanically by whitefly ( Bemisia tabaci ) semipersistent manner. Control this heavily dependent the management insect vector ...

Surveys of yellowing viruses in plastic tunnels and in open field crops of melon (Cucumis melo cultivar catalupo), oriental melon (C. melo cultivar oriental melon), and cucumber (C. sativus) were carried out in two melon-growing areas in 2014, Korea. Severe yellowing symptoms on older leaves of melon and chlorotic spots on younger leaves of melon were observed in the plastic tunnels. The sympto...

Both short- and long-term effects of Mg deficiency on carbohydrate metabolism were investigated in 6-year-old clonal Norway spruce (Picea abies (L.) Karst.) trees cultivated in sand culture with an optimal supply of nutrients, except for Mg which was supplied at 0.203, 0.041 and 0.005 mM to provide optimal, moderately deficient and severely deficient Mg supply, respectively. Annual changes in c...

Oil palm (Elaeis guineensis Jacq.) is an excellent source of vegetable oil for biodiesel production; however, there are still some limitations for its cultivation in Brazil such as Fatal Yellowing (FY) disease. FY has been studied for many years, but its causal agent has never been determined. In Colombia and nearby countries, it was reported that the causal agent of Fatal Yellowing (Pudrición ...