Stability of resistance to papaya ringspot virus in melon (Cucumis melo) and pumpkin (Cucurbita spp.)

The stability of resistance of cucurbit genotypes to Papaya ringspot virus was assessed using four isolates of PRSV-W and two isolates of PRSV-P. Following mechanical inoculation of the resistant accessions Cucurbita maxima ‘Redlands Trailblazer’, C. ecuadorensis and Cucumis melo ‘Cinco’ with these isolates, all proved to be highly resistant, based on symptom expression and ELISA, and are suitable for continued use in cucurbit breeding programs

Response of progeny from the cross Cucurbita moschata X C. ecuadorensis to infection with papaya ringspot virus type W and watermelon mosaic virus type 2

C. moschata cv. Butternut was compared with 11 selected lines produced through 3 backcrosses from cv. Butternut X C. ecuadorensis. The comparisons involved pruned or not, and naturally infected or mechanically inoculated with papaya ringspot (type W) potyvirus (PRV-W) plus watermelon mosaic II potyvirus (WMIIV). The objectives were to determine suitable evaluation procedures and the extent of genetic variation for resistance in the populations. All plants expressed moderately severe leaf symptoms which were only poorly correlated with fruit symptoms (r = 0.46) and yield (r = -0.56). Fruit distortion, which was greatest on manually inoculated and on pruned plants, differed among genotypes being highest in cv. Butternut. Fruit number was highest (5.5) on naturally infected, unpruned plants and lowest (3.3) on mechanically inoculated, pruned plants. The effects of pruning and method of inoculation on yield varied with genotype. Estimates of broad sense heritability on a plot mean basis were high (0.8) for yield and moderate (0.4) for fruit symptoms. It was concluded that sufficient variation existed to improve yield and reduce severity of fruit symptoms but not to decrease leaf symptoms. In the population studied, yield and severity of fruit symptoms on manually early-inoculated, unpruned plants should be the basis of selection

Response of progeny from the cross Cucurbita moschata × C. ecuadorensis to infection with papaya ringspot virus type W and watermelon mosaic virus type 2

C. moschata cv. Butternut was compared with 11 selected lines produced through 3 backcrosses from cv. Butternut × C. ecuadorensis. The comparisons involved pruned or not, and naturally infected or mechanically inoculated with papaya ringspot virus type W (PRV-W) plus watermelon mosaic virus type 2 (WMV-2)

Inheritance of resistance to zucchini yellow mosaic virus in Cucurbita maxima cv. Queensland Blue X C. ecuadorenesis

Inheritance of resistance to a Queensland isolate of ZYMV in Cucurbita ecuadorensis was investigated in a glasshouse using C. maxima as susceptible parent (P1), C. ecuadorensis as resistant parent (P2), F1 , F2 , backcross and self-pollinated backcross populations. Major gene models did not fit all the data well but estimates of heritability were high (h2B = 97%; h2N = 90%), implying that selection of C. maxima genotypes with resistance to ZYMV should be efficient

Inheritance of resistance to zucchini yellow mosaic virus in Cucurbita maxima cv. Queensland Blue × C. ecuadorenesis

Inheritance of resistance to a Queensland isolate of zucchini yellow mosaic potyvirus (ZYMV) in C. ecuadorensis was investigated in a greenhouse using C. maxima as susceptible parent (P1), C. ecuadorensis as resistant parent (P2), F1, F2, backcross and self-pollinated backcross populations

Retinal vascular caliber and brachial flow-mediated dilation: The multi-ethnic study of atherosclerosis

10.1161/STROKEAHA.110.581017Stroke4171343-134