Genetics of anthracnose panel canker disease resistance and its relationship with yield and growth characters in half-sib progenies of rubber tree (Hevea brasiliensis)

Abstract

Rubber tree [Hevea brasiliensis (Willd. ex Adr. de Juss.) Muell-Arg] anthracnose panel canker disease resistance, caused by Colletotrichum gloeosporioides (Penz.) Sacc., and growth and yield characters were assessed at three years old in the nursery, in 18 half-sib progenies. There were highly significant (P < 0.01) genetic differences among progenies for most characters. The genetic component of variance accounted for 3.37, 6.07, 12.74, 12.13, 19.82 and 3.58% of the phenotypic variance for anthracnose-infected area, anthracnose lesion stripe length, yield, girth, virgin bark thickness and total number of latex vessel rings, respectively. Narrow-sense heritability estimates for the above characters were 13.45, 24.30, 50.97, 48.52, 79.30 and 14.30%, respectively. No significant genetic correlations were found among anthracnose panel canker resistance, yield and growth characters. The frequency distribution of anthracnose-infected area and anthracnose lesion stripe length suggests polygenic control. Selecting the best three progenies out of 18 progenies would result in a genetic gain of 12.87 and 24.24% for infected area and lesion stripe length, respectively. The best five selected individuals out of 50 individuals within each progeny would result in a genetic gain of 9.47 and 24.62%, with a total gain of 22.34 and 48.87% for these two characters, respectively.<br>Estudos genéticos da relação da resistência da antracnose do painel, caracteres da produção e vigor da seringueira [Hevea brasiliensis (Willd. ex. Adr. de Juss.) Muell-Arg] foram conduzidos em 18 progenies de meios-irmãos na Estação Experimental de Pindorama, Estado de São Paulo. Os resultados obtidos mostraram diferenças genéticas significativas entre progenies para a maioria dos caracteres estudados. Os componentes genéticos da variância contribuíram com 3,37% da variância fenotípica para área infectada, 6,07% para comprimento de estrias, ambos causados pela anthracnose, 12,74% para produção, 12,13% para perímetro do caule, 19,82% para espessura de casca virgem e 3,58% para número total de vasos laticíferos. As herdabilidades no sentido restrito para os caracteres acima foram: 13,45%, 24,30%, 50,97%, 48,52%, 79,30% e 14,30%, respectivamente. Correlações significativas não foram encontradas entre antracnose do painel e caracteres da produção e perímetro do caule. A distribuição de freqüência de antracnose sugere que o caráter é poligênico. A seleção das três melhores progênies resultaria em um ganho genético para antracnose de 12,87% e 24,24% para área infectada e comprimento das estrias, respectivamente. A seleção dos cinco melhores indivíduos dentre os 50 indivíduos de cada progênie, para ambos os caracteres, resultaria em ganho genético de 9,47% e 24,62% com ganho total de 22,34% e 48,87%, respectivamente

Genetic variation in growth traits and yield of rubber trees (Hevea brasiliensis) growing in the Brazilian state of São Paulo

“…Nevertheless, heritabilities estimated in this study were within the range of those estimated in other studies of Hevea. (Moreti et al, 1994) and $ h i 2 = 0.47 (Boock et al, 1995;Gonçalves et al, 1999). The low values for individual plant heritability in our study could be attributable to large progeny by replication interaction and within progeny variances compared with the progeny variances.…”

“…This high variability among trees in open pollinated progenies might be an indicator of many effective pollen parents (Gonçalves et al,1999) …”

Expressão fenotípica de clones de seringueira na região noroeste do estado de São Paulo

“…Na avaliação dos clones quanto à incidência da antracnose do painel, causada pelo fungo Colletotrichum gloeosporioides (Penz.) Sacc., adotou-se em todas as plantas, a contagem do número de cancros acima da superfície de corte, e aplicou-se uma escala de notas graduais, em função do número de cancros presentes: 1-cancros ausentes; 2-um cancro; 3-dois cancros; 4-três a quatro cancros; 5-cinco ou mais cancros, considerando-se como resistentes (R) os clones nota 1; moderadamente resistentes (MR) para as notas 2 e 3, e suscetíveis (S), para as notas 4 e 5 (GONÇALVES et al, 1999).…”

Estimation of variance components and prediction of breeding values in rubber tree breeding using the REML/BLUP procedure

“…In general, their results have revealed that the genetic variation is largely accounted for by additive genetic variance (Valois et al, 1978;Paiva et al, 1982;Alika, 1985;Boock et al, 1995;Gonçalves et al, 1999Gonçalves et al, , 2004and Costa et al, 2000a and b). The results obtained in this study are in accordance with those.…”

“…Rubber tree improvement programs have been conducted in Brazil (Gonçalves et al, 1992(Gonçalves et al, , 1996(Gonçalves et al, , 1999(Gonçalves et al, , 2004Costa, 2000a and b;Paiva, 1994a and b) and in many other countries, such as Malaysia, Indonesia, Thailand, India and Ivory Coast (Tan, 1987;Simmonds, 1989;Priyadarshan, 2003;Clément-Demange et al, 1995. The yield improvement in rubber through breeding and selection has been spectacular.…”