Partition
of the genotype x environment interaction variance in effects explained by
molecular markers and deviations.

Heyder Diniz SILVA[1]

Roland VENCOVSKY2

Glauce Cristina Ricardo RUMIN2

§ ABSTRACT: One of the problems found in the QTL
analysis refer to the QTL x
environment interaction. We consider this aspect by partitioning the genotype x environment interaction variance in
components explained by the molecular
markers and deviations. This alowed
estimating the proportion of the genetic variance (pm),
and genotype x environment
variance (pms), explained by the markers.These estimators
are not affected by deviations of allelic frequencies of the markers in relation to the expected
values (1:2:1 in a F2 generation,
1:1 in a backcross, etc). However, there is a high probability of obtaining estimates out of the
parametric range,specially for high values of this proportion. Nevertheless,
these probabilities can be
reduced by increasing the number of replications and/or environments where the progenies are evaluated.

§ KEYWORDS: QTL, QTL’s x environment, Marker
assisted selection, variance components.

[1] 1Faculdade de
Matem´atica, Universidade Federal de Uberlˆandia, CEP 38408-902, Uberlˆandia -
MG, Brasil

2Departamento
de Gen´etica, Escola Superior de Agricultura Luiz de Queir´oz, Universidade de
S˜ao Paulo, CEP 13418-900, Piracicaba, SP, Brasil