Six F1 populations derived from crosses among 4 orchardgrass (Dactylis glomerata L.) cultivars were studied by morphological and simple sequence repeat molecular markers to test for hybrid vigor and a correlation between genetic distance and heterosis. Heterosis was observed for days to length of culm, leaf traits, tiller numbers, etc. Significant differences between obverse and inverse crosses were found for eleven traits. A cytoplasmic effect existed for the agronomic traits considered in this study.
Corn grits are used for various purposes such as flakes, snacks, livestock feed, hominy, extruded products, beer, etc. The grit size proportion varies according to the hybrid, and thus, once the use of the grits is linked to the particle size, determining the genetic effects is essential to develop hybrids for any specific use. For this purpose a complete diallel series of crosses, involving eight parents, was performed near Maringá, PR, Brazil.
Elephant grass is a tropical forage plant widely distributed throughout Brazil. It was first exclusively used in the livestock sector as cattle feed. The grass is characterized by its high productivity and photosynthetic capacity and is considered as an alternative source of renewable energy. Here, we estimated the general combining ability of the parents and specific combining ability of the hybrids based on morpho-agronomic biomass-quality traits. The experiment was conducted in a randomized block design with 3 replicates.
Wide hybridization expands the gene pool of cultivated species and can produce genotypes with practical value, often resistant to diseases. In plants, ISSRs are often used for hybrid identification as well as for diversity evaluation. We estimated genetic similarity among advanced genetic stocks of triticale hybrids and identified Aegilops juvenalis introgressions into triticale. Fourteen ISSR primers amplified from 12 to 23 DNA fragments. The number of polymorphic products per primer ranged from three to nine, with a mean of 5.1.
The intensity of genetic diversity amongst chickpea genotypes and their crosses is unknown. The current study investigated the genetic diversity of chickpea genotypes and their F1 crosses by using random amplified polymorphic DNA (RAPD) markers. We assessed the variation among six chickpea genotypes and 15 F1 crosses with the RAPD markers. The six parents and their 21 hybrids were carefully studied based on the presence or absence of bands. The level of polymorphism varied with different primers.
In breeding programs, commercial hybrids are frequently used as a source of inbred lines to obtain new hybrids. Considering that maize production is dependent on viable gametes, the selection of populations to obtain inbred lines with high meiotic stability could contribute to the formation of new silage corn hybrids adapted to specific region. We evaluated the meiotic stability of five commercial hybrids of silage corn used in southern Brazil with conventional squashing methods. All of them showed meiotic abnormalities.
Studies of genetic effects of early selection of maize based on seed quality traits are rare, especially those that use materials from different heterotic groups. These studies are also useful in tropical environments and for the advancement of sustainable agriculture with cropping during seasons not commonly used for cultivation.