Heterosis and combining ability of sweet pepper lines with resistance to yellow mosaic caused Pepper yellow mosaic virus PepYMV. / Heterose e capacidade combinatÃria de linhagens de pimentÃo resistentes ao mosaico amarelo causado por PepYMV (Pepper yellow mosaic virus)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2005

RESUMO

This paper reports on the magnitude of hetrosis, general and specific abilities in pepper hybrids, and on nature of gene action involved in expression of economic traits. Sixty-six genotypes were evaluated: five commercial hybrid checkes (Fortuna Super, Konan, Laser, Magali R and Natalie); 53 treatments composing a partial diallel cross [40 hybrids obtained from crosses between 8 group I lines (PIX-031D-165-04-01, PIX-031D-171-10-04; 171-10-08, PIX- 031D-171-10-10, PIX-031D-188-14-05, PIX-031D-188-14-07, PIX-031D- 18814-10 and PIX-031D-205-04-07) and 5 group II lines (Myr-29, PIM-003, PIM-004 and PIM-016), plus the 13 parental lines] The genotypes were tested in greenhouse trials in randomized complete block design with four replications. The following traits were evaluated total yield, mean fruit mass, early yield, mean mass of early fruit, fruit length, fruit width, fruit shape, russetting, depth of peduncle insertion and plant height. Reaction of lines and hybrids to mechanical inoculation with PepYMV was also evaluated. Hybrids were found with superior sets of traits relatively to the commercial checks: among them F1(PIX-031D- 205-04-07 x PIM-013); F1(PIX-031D-171-14-07 x PIM-013); F1(PIX-031D- 188-14-10 x PIM-004) and F1(PIX-031D-205-04-07 x PIM-004) which are high yielding, have large fruit sizes and are resistance to both PepYM and Phytophthora capsici. Heterosis values relative to mid parent ranged from - 22,46 to 42,24% for total yield; from -17,71 to 58,50% for mean fruit mass; from -15,65 to 58,60% for early yield; from -13,66 to 12,23% for mean mass of early fruit; from -2,72 to 12,02% for fruit length; from -10,37 to 7,69% for fruit width; form -21,36 to 13,40% for fruit shape; from -33,35 to 37,32% for russetting; from -23,86 to 20,74% peduncle insertion depth and from -19,02 to 48,32% for plant height. Heterosis relative to the standard hybrid check Magali R ranged from ranged from -19,00 to 24,00% for total yield; from -19,27 to 31,91% for mean fruit mass; from -11,89 to 42,94% for early yield; from -19,72 to 33,74% for mean mass of early fruit; from -13,36 to 7,83% for fruit length; from -8,68 to 8,33% for fruit width; form -15,12 to 67,44% for fruit shape; from -35,71 to 60,71 peduncle insertion depth and from -11,29 to 43,94 for plant height. Additive gene action was more important than non-additive action for mean ofearly fruit and for fruit russetting. Non-additive gene action was relatively more important for total and early yields, fruit length and depth of peduncle insertion. Both additive and non-additive gene action were important for mean fruit mass, fruit length and fruit shape. Both groups of parental lines in the partial diallel were in general highly divergent for the traits under consideration, both âper seâ and in their performance in hybrids. All lines derived from Magali R (groups I lines) were resistant to PepYMV. Resistance to PepYMV was effective not only in the homozygous lines, bus also inheterozygous hybrids.

ASSUNTO(S)

melhoramento genÃtico vegetal pepper plant breeding pimentÃo produÃÃo melhoramento vegetal production

ACESSO AO ARTIGO

Documentos Relacionados