Impact of Fertility Variation on Gene Diversity and Drift in two Clonal Seed Orchards of Teak (Tectona grandis Linn. f.)

Processos evolutivos e a origem das plantas cultivadas

“…Tal processo também foi importante na domesticação de espécies arbóreas como a teca (Tectona grandis) (VARGHESE et al, 2006) e de plantas daninhas que coevoluiram com as plantas cultivadas, como é o caso de Lythrum salicaria, a qual foi introduzida nos EUA a partir da Europa (ECKERT et al, 1996). Estimativas da intensidade dessa perda de diversidade genética encontrada nos ancestrais selvagens variam consideravelmente, desde 80% no milho (WRIGHT & GAUT, 2005) para 40-50% no girassol (LIU & BURKE, 2006) e 10-20% no arroz (ZHU et al, 2007).…”

Fertility Variation and Effective Population Size in A Teak Clonal Seed Orchard

“…Total fertility of a tree (or a clone, parent or genotype) (pi) was taken as the average of the male (mi) and female (fi) fertilities of each tree. When equal number of fruits is collected from each tree, the female fertility is assumed to be constant, equal to 1/N, where N is the census number of trees in the orchard (Varghese et al, 2006).…”

“…The reference population, which is a teak clonal seed orchard where that the plus trees were selected from, is considered to have very low group coancestry as it has an infinite number of unrelated individuals in its calculation. (Varghese et al, 2006): Group coancestry can be seen as the fraction of gene diversity lost since tree breeding was initiated.…”

“…A general lack of flowering in CSOs resulted in considerable fertility variation between clones (Kjaer, 1996in Varghese, et al, 2006. Although site has a marked effect on flowering habit (early flowering is observed in dry sites) of trees, fertility is reported to be strongly inherited (Kaosard, 1996in Varghese, et al, 2006 and the proportion of non-flowering clones may be high during low flowering years (Nikkanen and Ruotsalainen, 2000).…”

Contribución al conocimiento de las semillas de cinco especies forestales nativas y dos exóticas de Córdoba, Colombia

“…No obstante, en diferentes partes del mundo, varios estudios se han realizado sobre variabilidad gené ca, parámetros gené cos y el efecto de lotes mezclados de semillas en diferentes especies (Davidson et al, 1996;Murillo, 1998;Leishmann et al, 2000;Cordazzo, 2002;Costa et al, 2005;Rego et al, 2005;Varghese et al, 2006;Resende & Duarte, 2007;Tenorio-Galindo et al, 2008;Costa et al, 2009;Fofana et al, 2009;Rocha et al, 2011;Silva et al, 2012;Correa, 2012;Silveira et al, 2012;Correa et al, 2013;Souza & Fagundes, 2014). En general, los resultados han sido par culares y diferentes para cada especie, por ello se recomienda muy puntualmente analizar cada situación o caso por separado, con el objeto de tomar la mejor decisión de acuerdo con los obje vos puntuales que se busquen.…”