Breeding Potato for Quality Improvement

Potato is the most important non-cereal food crop in the world, that in general represent a non-fattening, nutritious and wholesome food, which supply important nutrients to the human diet. The potato tubers contain considerable amounts of carbohydrates, vitamin C, essential amino acids and minerals. The potato quality includes biological traits (e.g. proteins, carbohydrates and minerals); sensorial traits (e.g. flavor, texture); and industrial traits (e.g. tuber shape, cold sweetening and starch quality). These traits are deemed very important for fresh consumption, where they are most likely to influence consumer’s choice worldwide. Since most quality traits are genetically controlled, breeding work can successfully meet the quality of potato tubers and fulfills the needs of a changing and demanding world. Breeding potato for quality traits requires a continuous flow of new genes and allelic diversity into the Solanum tuberosum gene pool. However, recent advances in conventional and non-conventional breeding methods have significantly improved the possibilities of producing novel genetic variability for selection of new genotypes, especially when biotechnologists and plant breeders pool the existing resources. The genetics, biochemical and physiology of several quality traits is to be given equal importance that ultimately makes breeding efforts less empirical and more predictable

Molecular screening of tomato (Solanum lycopersicum L.) genotypes for resistance alleles against important biotic stresses

Molecular markers are vastly used as tool for screening of disease resistant/tolerant plant genotypes in early stage of growth in an environment-independent manner. In tomato (Solanum lycopersicum L.), the major biotic stresses like tomato yellow leaf curl virus, Fusarium wilt, tomato spotted wilt virus and root knot nematode cause severe crop loss. Recently, DNA based molecular markers for the screening of resistance alleles for the abovementioned diseases have been reported in tomato. In the present study, a total of eighteen tomato genotypes have been screened for the presence of possible resistance alleles, using sequence characterized amplified region(SCAR) molecular markers. Resistance allele-specific bands for Fusarium wilt disease, tomato spotted wilt disease and partial resistance allele-specifc band for root knot disease have been identified in some of the genotypes used in the present study. However, none of the genotypes was found to contain Ty3 resistance allele-specific band for resistance to tomato yellow leaf curl disease. Thus, possible resistance sources have been identified for three out of the four biotic stresses, mentioned earlier. Thus, the present study has screened the 18 tomato genotypes at molecular level for presence of resistance alleles for biotic stress, which might be further evaluated and explored in future tomato breeding programmes, targeting biotic stress resistance in tomato. At the same time, the study documents the applicability of molecular markers for rapid disease screening in tomato in an environment independent manner

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Not AvailableDrought or moisture stress is one of the most significant environmental stresses causing huge loss to the agriculture worldwide. Vegetables are more sensitive to drought as compare to many other crops. Improving yield under drought is a major goal of plant breeding. An understanding of genetic basis of drought tolerance is a pre-requisite for plant breeders to evolve superior genotype through conventional breeding methodology. Drought is often accompanied by relatively high temperatures, which promote evapotranspiration and affects photosynthetic kinetics, thus intensifying the effects of drought and further reducing crop yields. Traditionally, plant breeders have addressed the problem of environmental stress by selecting for suitability of performance over a series of environmental conditions using extensive testing and biometrical approaches. Progress requires the introduction of traits that reduce the gap between yield potential and actual yield in drought-prone environments. An attempt has been made in this review to compile the scattered information on concepts, genetics, and traditional breeding approaches of drought tolerance with suitable illustrations. A comprehensive list of genes responsible for drought and examples of species and genotypes of vegetables with drought tolerance has also been provided.Not Availabl