I. Goldringer et al., THEORETICAL COMPARISON OF RECURRENT SELECTION METHODS FOR THE IMPROVEMENT OF SELF-POLLINATED CROPS, Crop science, 36(5), 1996, pp. 1171-1180
Choosing a recurrent selection strategy depends on the resources of th
e breeder and on the efficiency of the possible selection schemes. An
experimental comparison is difficult and time consuming, but a theoret
ical comparison may provide some guidelines. This study was conducted
to compare theoretically the efficiency of different recurrent selecti
on methods of improving the line value of a population, in this case,
of self-pollinated crops. We considered five methods that are well ada
pted to breeding autogamous species: single-doubled-haploid descent se
lection with a 4-yr (SDH1) or 5-yr cycle (SDH2); selection on S-1 fami
ly (S-1); selection on S-2 bulk (S2B) and on S-2 family (S2F); and two
other methods-selection on half-sib progeny (HSP) and on full-sib Fam
ily (FSF)- used for the improvement of per se or combining ability val
ues. Analytical expressions for the corresponding expected genetic adv
ances (per growing season) were derived and compared according to the
values of the narrow sense heritability and the variance components in
an inbred system. SDH1 always appeared as the most efficient method,
SDH2 and S2F were the next best methods for realistic values of parame
ters. S-1 efficiency was restricted to very high heritabilities and ad
ditive variances, Gain due to higher gene fixation in the St families
balanced the short cycle of S-1. As the proportion of nonadditive and
environmental effects increased, SDH2 became more efficient than S2F,
and S2F more efficient than S-1, S2B was always the least efficient ex
cept when the possibility to reduce the between-plot environmental var
iance through a larger plot size was taken into account, In that case,
S2B could be more efficient than S2F for medium to low heritabilities
. HSP and FSF appeared only marginally as the second or third most eff
icient methods. SDH is the best method to improve autogamous crops eve
n though cycle length is 5 yr; however, if haplo-diploidization techno
logies are not available or are too expensive, a selection scheme base
d on SI family may be the most economical method.