Parâmetros genéticos, dissimilaridade e desempenho per se em acessos de abóbora

Abstract

Genetic parameters, dissimilarity and performance of pumpkin accessionsPumpkin is very important in human and animal food, especially concerning family farms. The germplasm bank of vegetables of Universidade Federal de Viçosa (Federal University of Viçosa, UFV-BGH), Brazil, has several pumpkin accessions with wide genetic variability. All this genetic variability is of great importance for plant breeding. However, little is known about the true potential of BGH-UFV, because there are few scientific papers published with information on these accessions. The objective was to obtain information on genetic parameters, dissimilarity and performance of BGH-UFV pumpkin accessions. We evaluated 11 morphological descriptors of 55 accessions and three cultivars. The genetic parameters, expected gain with selection, phenotypic, genotypic and environmental correlations were estimated. For the dissimilarity study, the Tocher test was carried out and graphic dispersion of the canonical variables was evaluated. There was genetic variability among accessions, with a predominance of genetic effects over the environment. Higher gain selection for mass per fruit, plant appearance and location of the first male flower node are expected. The commercial cultivars Butternut and Tetsukabuto have excelled due to the lower mass per fruit and precocity of flowering, but they had the worst results in terms of phytosanitary aspect. There are negative correlation estimates between the phytosanitary aspect and growth habit, length and growth rate of the main stem, indicating that compact plants may have greater phytossanitary problems. Crossing accession BGH-7003 or cultivar Butternut with accessions BGH-1946 or BGH-7765 can generate progenies with potential for breeding.

Germplasm of Brazilian winter squash (Cucurbita moschataD.) displays vast genetic variability, allowing identification of promising genotypes for agro-morphological traits

“…The variability denoted by the clustering of the accessions corroborates the high estimates of genetic variances and heritabilities displayed by most of the agronomic characteristics, the total carotenoid content of the fruit pulp, and the seed characteristics such as MSF, MS/F and NSF (Table 3). This is also analogous to other studies involving the analysis of variability in this crop in Brazil [18, 20].…”

“…The samples of C. moschata maintained by BGH-UFV constitute one of the largest collections of this species in Brazil [32]. Studies involving the assessment of this germplasm have allowed the identification of accessions with crucial characteristics for this crop, such as phytopathogenic resistance, and for its genetic improvement in terms of the productive and nutritional aspects of its fruits and seed oil [34, 20, 12, 35]. Although BGH-UFV maintains more than 350 accessions of Cucurbita ssp.…”

“…Associated with its socio-economic importance, C. moschata germplasm commonly expresses high genetic variability in all regions where it occurs [15, 16, 17], especially in Brazil [18, 19, 20]. Archaeological evidence indicates that this species was present in Latin America prior to colonisation, and appears to have already been an important component in the diet of the native peoples living there [21, 22, 23].…”

“…The UFV Vegetable Germplasm Bank (BGH-UFV) maintains more than 350 accessions of C. moschata , comprising one of the largest collections of this species in the country [32]. This bank continually carries out work on the characterisation and evaluation of this germplasm [33], which has allowed the identification of sources of resistance for important phyto-pathogenic agents of this crop [34], and for its improvement in terms of production [20] and nutritional aspects of fruits and seed oil [12, 35]. The potential of this germplasm as a source of genes for the improvement of this crop, along with the possibility of elucidating the genetic mechanisms linked to important production parameters, justifies the continuation of studies on its assessment and use.…”

Brazilian germplasm of winter squash (Cucurbita moschata D.) displays vast genetic variability, allowing identification of promising genotypes for agro-morphological traits

“…Associated with its socio-economic importance, C. moschata germplasm commonly expresses high genetic variability in all regions where it occurs [15,16,17,18], especially in Brazil [19,20,21]. Archaeological evidence indicates that this species was present in Latin America prior to colonisation, and appears to have already been an important component in the diet of the native peoples living there [22,23,24].…”