Proposta para ampliação da base genética por meio de cruzamento interespecífico no pré-melhoramento do tomateiro / Proposal for amplification the genetic base for interespecific cross in tomato pre-breeding.
AUTOR(ES)
Gabriel Belfort Rodrigues
FONTE
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia
DATA DE PUBLICAÇÃO
12/03/2010
RESUMO
The aim of this study was to evaluate: 1 - the variability among families resistant PepYMV from the crossing between S.lycopersicum and S.habrochaites; 2 - the contribution of variability in this cross for the breeding of tomato. The diversity assessment was performed with a square lattice design experiment with two replications and three plants per plot. The lattice was less efficient than randomized block design. In the analysis there were significant differences for all characteristics. The Scott-Knott test was detected over a group of medium only for EPP, DE, PTF, PMF, SST, AT and QO. Cluster analysis of Tocher formed 4 groups, but there was not a group formed by both families and witnesses. The canonical variables analysis confirmed the divergence between the families F2:5 and witnesses. In the test of importance of traits you can delete CFo and LFo. We conclude that the families F2:5 are in fact divergent and in relation to witnesses, representing a source of variation for new genes. With the confirmation of the existence of vaiabilidade among the 45 families F2:5 were selected five least and five more divergent than witnesses ( Santa Clara , Debora , Fanny and Alambra ) to construct the partial diallel. The 40 hybrids and 14 parents were assessed in randomized blocks designs with three replications and four plants per plot. There was no significant in analysis of variance only for EPP, CE and CM. In the Scott Knott test hybrids in the same group there were witnesses. In the analysis of the crosses was observed for group I (families F2:5) significance for general combining ability (GCA) for CFo, DE, SST, AT, QO and FF. For 11 traits for the estimates of GCA for the most divergent families were equal to or larger family less divergent. For Group II (witness) to CGC was significant for the CFO, LFO, DE, PTF, pH and QO. In this group the cultivars Santa Clara and Fanny stood out in the estimates. For specific combining ability was 53% of the features significant by F test For the traits that the average household is greater than the average witness the selection of families for the most divergent backcross program is more advantageous.
ASSUNTO(S)
genetic base genética quantitativa recursos genéticos base genética pré-melhoramento melhoramento vegetal pre-breeding genetic resources quantitative genetics
