8th INTERNATIONAL WHEAT CONFERENCE

effeCTS of SPeCIfIC RhT ANd PPd ALLeLeS oN
AgRoNomIC TRAITS IN The euRoPeAN WINTeR WheAT
CuLTIVARS
Václav Šíp 1 , Jana Chrpová 1 , Zbyněk Milec 1 ,
Kateřina Pánková 1 and John W. Snape 2
1 Crop Research Institute, Department of Genetics and Plant Breeding Methods, Drnovská
507, Prague – Ruzyně, CZ-161 06, Czech Republic;
2 John Innes Centre, Norwich Research Park, Colney, Norwich NR4 7UH, UK
E-mail Address: sip@vurv.cz
Winter wheat cultivars grown in the Czech and Slovak Republics during the period 1976-
2007 were analyzed for the presence of alleles at Rht and Ppd loci and examined for a
range of agronomic traits using official data from multi-location trials. Out of four allelic
variants detected at the Xgwm261 locus on chromosome 2D (174-bp, 192-bp, 165-bp and
198-bp), the 174-bp allele predominated in the area of Czech Republic and the 192-bp
(Rht8) allele in neighbouring Slovakia. GA insensitive alleles on chromosomes 4B and
4D were detected in 43 of 116 cultivars (37.1%) and the photoperiod insensitive allele
Ppd-D1a on 2D in 65 cultivars (55.2%). The analyses of effects of year of registration on
allele frequency showed a decline in GA insensitive cultivars released recently in both
countries, and great changes in the frequency of the ´2D alleles´ during the period 1981-
2007 in the Czech Republic (increase in frequency of the 165-bp and 174-bp alleles and
decrease in frequency of 192-bp allele). Founder effects of the genetic backgrounds used
as donors on yielding ability, grain quality and also resistance to important stress factors
were detected; however, also selection for an appropriate growth type (e.g. optimal plant
height, suitable earliness) could contribute significantly to the improvement of agronomic
traits. The exploitation of the Xgmw261 174-bp allele (and perhaps also the165-bp allele)
in combination with Ppd-D1b appears to be beneficial for obtaining broader adaptability
in grain yield (which is becoming more and more important in all European regions),
but requires careful selection for the improvement of bread-making quality and winterhardiness
level when using new sources of Rht-D1b. The high potential of East European
cultivars (mainly of Russian or Ukrainian origin) can be exploited from this aspect. It
may be easier to obtain desirable agronomic performance by not using the environmentally
sensitive Norin10 Rht genes (Rht-D1b having also negative effect on Fusarium head
blight response), and to select taller lodging resistant plants. Allelic variants of Rht and
Ppd genes are now detectable with the use of molecular markers and this is beneficial for
modelling the optimum plant type for certain growing conditions, optimizing the breeding
strategy and increasing the efficiency of selection.
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