Genetic variation and interrelationships ofagronomic characters in landraces of bread wheat fromsoutheastern Iran

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• 作者：Moghaddam ; M. ; Ehdaie ; B. ; Waines ; J.G.
• 关键词：Triticum aestivum L. ; bread wheat ; landraces ; genetic variation ; path ; analysis ; yield and yield components ; selection ; Iran
• 刊名：Euphytica
• 出版年：1997
• 出版时间：1997
• 年：1997
• 卷：95
• 期：3
• 页码：361-369
• 全文大小：69 KB
• 刊物类别：Biomedical and Life Sciences
• 刊物主题：Life Sciences<br>Plant Physiology<br>Plant Sciences<br>Ecology<br>
• 出版者：Springer Netherlands
• ISSN：1573-5060

文摘

There is renewed interest in wheat landraces asimportant sources of genetic variation for agronomiccharacters. Fifty-three pure lines of bread wheat(Triticum aestivum L.) derived from sevenlandraces collected from southeastern Iran were usedto estimate genetic variation and heritability for 13developmental and quantitative characters.Path-analysis was used to partition the geneticcorrelations between grain yield and six grainyield-related traits. Mean values of landraces werealso compared with three improved cultivars fromCalifornia and Iran. Genotypic differences among thelandraces and among the pure lines collected from thelandraces were highly significant for all charactersconsidered. Compared with the modern cultivars, thelandrace genotypes were, on average, later in days toheading and taller than the cultivars but had lowervalues for number of grains per spike, 1000-grainweight, grain yield and harvest index. Some landracegenotypes were similar to the modern cultivars forgrain yield. Moderate to high genetic variation wasdisplayed by number of grains per spike, number ofspikes per plant, 1000-grain weight, and harvestindex. The heritability estimates ranged from 59% forgrain yield to 99% for days to anthesis. Expectedgenetic advance (as % of the mean) was ≈34%for number of spikes per plant, number of grains perspike, and 1000-grain weight. Days to heading and toanthesis correlated positively with number of spikesper plant, shoot biomass, and straw biomass butnegatively with number of grains per spike and harvestindex. The strong direct effect of number of spikesper plant on grain yield was completelycounterbalanced by its indirect negative effects vianumber of grains per spike and 1000-grain weight.Number of grains per spike and 1000-grain weight werepositively correlated with grain yield, and they hadlarge direct effects. These two characters, however,were negatively correlated and exhibited a substantialcounterbalance effect via one another and via numberof spikes per plant. The landraces could be improvedby intercrossing the promising genotypes identified inthis study, with simultaneous selection for earliness,fewer number of spikes per plant, greater number ofgrains per spike and heavier grains. For furtherimprovement, crossing programs between the landracesand introduced germplasm may be necessary.