A total of 33 simple sequence repeats (SSRs) was analyzed in 52 genotypes of Hordeum spontaneum originally collected from two different soil types (Terra rossa and Basalt) at Tabigha in Israel. Data on the performance of developmental, morphological, and yield‐related traits under well‐watered control and water‐stress conditions were available from previous experimentation, and powdery mildew susceptibility was scored. Regression analyses based on SSR allele class differences were performed. Highly significant associations were detected at the SSR loci Bmac181 (on chromosome 4H) and Bmac316 (6H) for water ‐stress tolerance and powdery mildew resistance, respectively. The study shows that association mapping using SSRs and genetically diverse germplasm provides an effective means of relating genotypes to complex quantitative phenotypes. 相似文献
Summary The slow kinetics of chlorophyll fluorescence were examined in seven potato genotypes grown either fully irrigated or droughted
from the time of plant emergence. Constant and variable fluorescence (Fo andFv respectively) declined with time in plants from both irrigated and droughted treatments, but the decline was greater in droughted
than irrigated plants. However, the yield of variable fluorescence (Fv/(Fo+Fv)) was unaffected by the drought treatment. The main effect of drought was upon the quenching of variable fluorescence. Both
the half life of the decay of variable fluorescence (q1/2) and the secondary maximum (M) were significantly greater in the droughted plants than in those from the irrigated treatment. Significant differences between
genotypes were found forFv/(Fo+Fv),M andq1/2. Genotype-by-treatment interactions were non-significant for all the variables examined. Changes in chlorophyll fluorescence
transients were not closely related to changes in leaf water potential. 相似文献
Summary Relations between measurements of the slow kinetics of chlorophyll fluorescence and growth and yield were examined in seven
potato genotypes grown either fully irrigated or droughted from the time of plant emergence. Drought reduced total dry matter
production and yields and increased tuber dry matter concentration. Drought increased harvest index in cv. Spunta, but decreased
it in cv. Pentland Crown. Total dry matter production was correlated with each of constant fluorescence, variable fluorescence
and the half life of the decay in variable fluorescence. These correlations were determined largely by the effect of treatment,
and did not discriminate effectively between genotypes within a treatment. 相似文献
Soybean plants were subjected, during their growing seasons, to well-watered and water-stressed conditions, and three levels of ozone concentration (zero, low and high) in open top chambers (OTCs). At the end of the soybean growing season accumulated AOT40 values were zero, 3400 and 9000 ppb h for the filtered (control), low and high levels of ozone concentration, respectively.
In well-watered conditions, an increase in ozone concentration led to a reduction in leaf area, dry matter and reproductive organs. Whereas, an increase in ozone had no effect on plants in water-stressed conditions. At a high level of ozone concentration, there was a 47% reduction in yield and a 25% reduction in WUE in comparison with the control treatment. The reduction in yield was due to a lower number of pods per plant and 1000-grain weight. Despite changes in the grain yield, the yield quality was not altered by ozone.
During the 3-year study, AOT40 was significantly correlated with the leaf area and the final above-ground dry matter. The latter was less sensitive to ozone than leaf area. These results were reliable and would be useful in soybean yield-prediction models.
Finally, the conclusion highlights the reliability of the approach adopted, which was to make observations on various time scales (hourly, daily and entire crop cycle). 相似文献