Rl. Villareal et al., AGRONOMIC PERFORMANCE OF CHROMOSOMES 1B AND T1BL.1RS NEAR-ISOLINES INTHE SPRING BREAD WHEAT SERI M82, Euphytica, 103(2), 1998, pp. 195-202
The T1BL.1RS wheat (Triticum aestivum L.) - rye (Secale cereale L.) tr
anslocations have been of particular interest and are widely used in b
read wheat breeding programs. The objective of this study was to deter
mine the effect of the T1BL.1RS chromosome on grain yield and its comp
onents using 20 near-isolines of spring bread wheat cultivar 'Seri M82
' (10 homozygous for chromosome 1B substitution and 10 homozygous for
T1BL.1RS). The test lines have been produced by substituting the 1B ch
romosome in Seri M82 (T1BL.1RS, T1BL.1RS) through backrossing. Two fie
ld experiments were evaluated under optimum (five irrigations) and red
uced (one irrigation) moisture conditions for two consecutive producti
on cycles at the Mexican National Agricultural Research Institute, Ciu
dad Obregon, Sonora, Mexico. The presence of T1BL.1RS had a significan
t effect on grain yield, harvest index, grains/m(2), grains/spike, 100
0-grain weight, test weight, flowering date and physiological maturity
in both moisture conditions. The agronomic advantage of the 1B substi
tution lines on above-ground biomass yield at maturity, spikes/m(2) an
d grain-filling duration was expressed only under the optimum moisture
condition. The presence of T1BL.1RS increased grain yield 1.6% and 11
.3% for optimum and reduced moisture conditions, respectively. These r
esults encourage further use of T1BL.1RS wheats in improving agronomic
traits, especially for reduced irrigation or rainfed environments.