A tomato cultivar with high quality fruit and a long shelf life is a main goal in tomato breeding and it would be achieved using wild germplasm. The objective of this work was to explore the inheritance for fruit quality traits, especially fruit shelf life, in three tomato crosses using a standard Argentinean cultivar (Ca, cv 'Caimanta'), a ripening mutant (nor, homozygous for the nor gene) of Solanum lycopersicum, and a wild cherry type (Ce, LA1385 of S. lycopersicum var. cerasiforme). The wild parent had a shorter fruit shelf life than the mutant genotype but higher than Ca. When the Ce genotype was analyzed in hybrid combination, the F 1 (Ca9Ce) was similar to the wild genotype for shelf life whereas the F 1 (nor 9 Ce) had a longer shelf life. Both F 1 crosses and backcrosses to the cherry type genotype had significantly lower fruit weight than the cultivated genotypes but higher than the cherry type parent. In the F 2 analysis, it was found that the inheritance underlying quality traits is complex since non allelic interactions were detected. A significant additive genetic variance was found for fruit shelf life as well as for other fruit quality traits in each cross. The genetic parameters analyzed by mean values and variances in parental, F 1 and F 2 and backcross generations indicated that the cross between the normal ripening cultivar and LA1385 of S. lycopersicum var. cerasiforme offers the best possibility to obtain long shelf life tomato genotypes with good fruit quality.

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The development of imidazolinone (IMI) resistant sunflower cultivars represents a great advantage in controlling weeds. The aim of this study was to evaluate the response of sunflower genotypes to the presence of IMIs in a soil-less bioassay. Six genotypes differing in IMI resistance were planted in pots filled with perlite and watered with different imazapyr doses. Differences among resistant, intermediate and susceptible genotypes were observed 8-15 days after planting. The susceptible genotype showed stunted plantlets. The intermediate genotypes developed reduced lateral roots when exposed to imazapyr. The resistant inbred line was only affected at the highest herbicide concentrations. Differences in aerial growth were also observed among genotypes. The bioassay described in this study is a rapid, simple and cost-effective method for early screening herbicide resistant genotypes. This diagnostic test could be a useful tool when breeding for IMI resistance in sunflower.