Genotype-environment interaction and phenotypic stability for girth growth and rubber yield of Hevea clones in São Paulo State, Brazil

Abstract

The best-yielding, best vigour and most stable Hevea clones are identified by growing clones in different environments. However, research on the stability in Hevea brasiliensis (Willd. Adr. ex Juss.) Muell.-Arg. is scarce. The objectives of this work were to assess genotype-environment interaction and determine stable genotypes. Stability analysis were performed on results for girth growth and rubber yield of seven clones from five comparative trials conducted over 10 years (girth growth) and four years (rubber yield) in São Paulo State, Brazil. Stability was estimated using the Eberhart and Russell (1966) method. Year by location and location variability were the dominant sources of interactions. The stability analysis identified GT 1 and IAN 873 as the most stable clones for girth growth and rubber yield respectively since their regression coefficients were almost the unity (β = 1) and they had one of the lowest deviations from regressions (S di 2 ). Their coefficient of determination (R 2 ) was as high as 89.5% and 89.8%confirming their stability. In contrast, clones such as PB 235, PR 261, and RRIM 701 for girth growth and clones such as GT 1 for rubber yield with regression coefficients greater than one were regarded as sensitive to environment changes.

Estimation of genetic parameters in rubber progenies

“…Gonçalves et al (2009a) found significant effects at 1% probability in a study with progenies at more than one location. The results of test evaluating the genotype can be used to select and recommend clones adapted to a particular agro-climatic condition if the differences can be defined according to environmental factors (Gonçalves et al 2003). …”

“…The high coefficient of variation for rubber yield indicates that the experimental data are subject to experimental errors, despite being within the normal standard for rubber tree (Costa et al 2000, Gonçalves et al 2003.…”

Adaptability, stability, productivity and genetic parameters in slash pine second-generation families in early age

“…MHPRVG*MH value shows the average genotypic value of the progenies in the two sites, and this amount has already been penalized by instability and capitalized by adaptability (Carbonell et al, 2007). Environmental variations can interfere at GxE interactions, thus it is important and necessary to identify stable genotypes that produce well in various conditions (Gonçalves et al, 2003).…”

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

“…Results concerning genetic parameter estimates, genotype x environment interaction, mating system and genetic gain predictions were reported in a number of papers (Gonçalves et al, 1992(Gonçalves et al, , 2003Boock et al, 1995;Costa et al, 2000b).…”