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... The Passiflora L. (Passifloraceae) genus consists of about 500 species widely distributed throughout tropical and subtropical regions, commonly known as the passion flower. The passion flowers are considered ornamental plants because of the exotic beauty of their flowers and variant foliage. Since their introduction to the Old World, around 1625, seventeenth century, they have been used to decorat ...
... For commercial development of hybrids the four pre-requisites are; availability of perfect male-sterility system, efficient mass pollen transfer mechanism, hybrid vigor, and the large scale seed production of hybrids for commercialization. The type of male-sterility governs the acceptance of hybrids by farmers. Genetic male-sterility (GMS) system was not accepted by farmers due to the economics of ...
... In the past 20 years, very little progress has been achieved in reducing food insecurity, child malnutrition and hunger in Africa. Under-nutrition and micronutrients deficiencies are widespread and affect mainly women and children. To address these problems, increased consumption of African leafy vegetables is promoted as sources of both micronutrients and bio-active compounds. Widely promoted Afr ...
... Low soil nitrogen (Low N), Striga hermonthica and recurrent drought are major constraints to maize production and productivity in sub-Saharan Africa (SSA). Only a few extra-early maturing hybrids with combined tolerance to drought, Striga and low N have been commercialized in SSA. The objectives of the study were to determine the general combining ability (GCA) and specific combining ability (SCA) ...
... We developed new F₁ hybrids of Chinese cabbage (Brassica rapa L. ssp. pekinensis) that allow cultivation earlier in spring without heating by introducing extremely late-bolting alleles at two homologs of the flowering repressor Flowering Locus C (BrFLC2 and BrFLC3) from non-heading ‘Leafy Green Parental Line No. 2’. These new F₁ hybrids were produced by the following four steps. First, the extreme ...
... Maize (Zea mays L.) is the most important cereal crop produced in Ghana. However, yield of the crop is generally low, producing just about 1.7 t/ha. The low yield is attributed to continuous use of local/unimproved varieties. Generally, hybrid varieties have proven to out-yield the local/unimproved varieties due to improved vigour. Development of hybrid varieties depend on good understanding of co ...
... Soybean scientists in China have tried to utilize heterosis for yield enhancement. A number of cytoplasmic-nuclear male-sterile (CMS) lines, their maintainers and restorers were developed, but the commercialized hybrid seed production is still a bottleneck. Five soybean CMS lines with their maintainers and restorers were studied for the sufficiency of viable and effective pollens from maintainers/ ...
... Present study was conducted to evaluate the relationship between parental genetic distances, combining ability and heterosis in rapeseed (Brassica napus L.). Nine elite inbreds widely used in Chinese rapeseed breeding programs, were crossed in a diallel design to develop 36 hybrids and evaluated together with their parents across four environments. Genetic distances among lines were measured from ...
... The development of hybrid cultivars is one of the most important contributions of a breeding program. A high allelic fixation of the parent lines is essential to guarantee the uniformity of developed hybrids. In this sense, papaya segregation has been observed in the parent lines, impacting the pattern of the hybrids obtained and, consequently, their commercialization. Thus, this study aimed to ev ...