Apple is a fruit crop cultivated worldwide. Apple orchards are exposed to a diverse set of environmental and biological factors that affect the productivity and sustainability of the culture. Many of the efforts and costs for apple production rely on reducing the incidence of fungal diseases, and one of the main diseases is apple scab caused by the fungus Venturia inaequalis. The economic impac...

fire blight disease caused by erwinia amylovora is a destructive disease of pome fruits including apple worldwide. use of resistant cultivars is the most efficient method of disease control. in the present research, we investigated genetic resistance of 89 local and imported commercial apple cultivars in natural contaminated conditions to the bacterial disease using beltsville scoring system (u...

Ten cultivars and 13 germplasms of white clover (Trifolium repens) were evaluated in the greenhouse for resistance to the southern root-knot nematode, Meloidogyne incognita race 4. One hundred plants of each cultivar or germplasm were rated for percentage of the root system galled (PRSG) at 60 days after inoculation with root-knot nematode eggs. Tillman (9%) and SRVR (19%) had the highest perce...

We show here that the pvr2 locus in pepper, conferring recessive resistance against strains of potato virus Y (PVY), corresponds to a eukaryotic initiation factor 4E (eIF4E) gene. RFLP analysis on the PVY-susceptible and resistant pepper cultivars, using an eIF4E cDNA from tobacco as probe, revealed perfect map co-segregation between a polymorphism in the eIF4E gene and the pvr2 alleles, pvr2(1...

A sprouting-resistant and a sprouting-susceptible wheat cultivar were utilized to examine the role of ABA levels and sensitivity responses in wheat embryonic germination. Endogenous embryonic ABA levels were measured in both cultivars throughout grain maturation utilizing a new and sensitive ABA immunoassay. Embryonic ABA levels of each cultivar were similar with the sprouting-susceptible culti...

After completing a three-year (1995-97) evaluation of bell pepper cultivars under induced bacterial spot (Xanthomonas campestris pv. vesicatoria or Xcv) and bacterial spot-free environments, we began a new series of trials in 2000 to compare new cultivars with previously recommended cultivars that were either highly resistant (‘Boynton Bell’) and/or that had very attractive fruits (‘X3R Wizard’...

The total phenol content, peroxidase and polyphenol oxidase enzyme activities and the total protein profile in tomato cultivars (Lycopersicon esculantum Mill.), tolerant and susceptible to Fusarium wilt disease was studied. The tolerant cultivars of tomato viz., FEB-2, FEB-4, FloraDade and NF-31 had significantly higher phenol content as well as peroxidase and polyphenol oxidase activities than...

Fusarium oxysporum f. sp. ciceri (Foc), one of the most important fungal pathogen of chickpea, is a constant threat to this crop plant. In the present study gene expression analysis of chickpea roots during Foc infection was performed using various approaches. cDNAs derived from total mRNA during infection process of susceptible (JG62) and resistant (Digvijay) cultivars, were amplified using ra...

Several studies have expressed concerns about the effects of gene flow from transgenic herbicide-resistant crops to their wild relatives, but no major problems have been observed. This review describes a case study in which what has been feared in transgenics regarding gene flow has actually changed biodiversity and people's lives. Nontransgenic imidazolinone-resistant rice (IMI-rice) cultivars...

The use of resistant cultivars is one of the most practical and cost-efficient strategies for managing plant diseases. However, the efficiency of resistant cultivars in disease management is limited by pathogenic variability in pathogen populations. Knowledge of the evolutionary history and potential of the pathogen population may help to optimize the management of disease-resistance genes, irr...