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Inheritance of fiber quality and lint yield in a chemically mutated population of cotton 总被引:2,自引:0,他引:2
Andy D. Herring Dick L. Auld M. Dean Ethridge Eric F. Hequet E. Bechere Cary J. Green Roy G. Cantrell 《Euphytica》2004,136(3):333-339
The narrow germplasm base of the upland cotton (Gossypium hirsutum L.), grown on the Texas high plains historically, has limited improvement of fiber quality. Chemical mutagenesis and subsequent selection have helped the development of lines with improved fiber quality in cultivars adapted to this region. This study was conducted to determine the inheritance of improvements in fiber quality. M3 lines with divergent fiber properties of micronaire, length, and strength were selected from a population of Paymaster HS 200 treated with 3% v/v ethyl methanesulfonate (EMS) for two hours. The 115 selected lines of M4 and M5 generation were evaluated for fiber quality and lint yield. Regression of the M4 and M5 on the M3 generation, as well as the M5 on the M4 was used to generate narrow sense heritability coefficients. Significant variations were observed between the mutant lines in all generations except for lint yield in the M5 (1997). The highest heritability estimates were found in fiber length (h
2= 0.29** to 0.46**). Micronaire and strength showed intermediate heritability estimates of h
2= 0.14 to 0.19, while lint yield had a very low heritability estimate of h
2= 0.03. Fiber length and strength were correlated (r= 0.58** to 0.46**) in all the three generations. The mutants identified in these studies have the potential to improve fiber quality of upland cotton without introducing alien genes that may reduce adaptation to short growing season production regions. 相似文献
3.
Getachew Belay T. Tesemma E. Bechere D. Mitiku 《Genetic Resources and Crop Evolution》1995,42(4):387-391
Summary Purple-grain tetraploid wheats (Triticum turgidum L.) are widely cultivated in the Ethiopian highlands despite the claim that they have lower industrial quality properties
and market prices than the white or red/brown seed-colour types. In an attempt to find a possible explanation for this, the
three seed-colour groups were compared for grain yield, other 11 agronomic traits and protein content. Five traits displayed
significant differences between seed colour groups where the purple-seed was superior; earlier maturity, shorter height, and
higher fertility, tillering capacity and harvest index. Most of these are important adaptive traits to waterlogging stress
on dark-clay soils (pellic vertisols) where the great bulk of the Ethiopian tetraploid wheats have been grown. Furthermore,
among the three seed-colour groups, purple-seed wheat has the best malting quality for the preparation of arekie, a locally
distilled spirituous liquor. It, therefore, appears that both natural and human selections have been reponsible for their
continued cultivation. Hence, the notion that purple-seeded wheat is the “least preferred” should be interpreted carefully
not to necessarily address the whole community in Ethiopia. As to their taxonomy, all tetraploid wheat taxa (T. turgidum L. sensu lato, 2n = 4x = 28) that are found in Ethiopia, with the possible exception of T. dicoccon Shrank (locally known
as Adja), may possess the purple pericarp-colour, although in varying frequencies; very low inT. polonicum L., and high inT. carthlicum Nevski andT. durum Desf. 相似文献
4.
Utilization of cotton (Gossypium hirsutum L.) germplasm for genetic improvement of fiber properties requires determination of genetic effects in the germplasm lines. A study was designed to analyze genetic populations derived from multiple crosses between nine germplasm lines as male parents and five cultivars and elite breeding lines as female parents to determine genetic values of fiber properties. Parents and F2 populations were planted at 2 field sites in 2010 and 2011 with 4 and 3 replicates, respectively, and parents and F3 populations were planted at 2 field sites in 2011 with 3 replicates. Lint yield and seven fiber properties were analyzed by an additive and dominant model with genotype by environment interaction effects. Significant additive and dominant effects were identified for both lint yield and fiber properties. Germplasm lines JC60, JC65, JC186, and SP205 were good general combiners for micronaire, elongation, strength, 50 % span length, short fiber content, and fineness. Six to fifteen crosses were detected with favorable heterozygous dominant effects for lint yield and diverse fiber traits, which suggest useful heterosis of these hybrids. Favorable additive correlations were identified between fiber properties such as micronaire versus 50 % span length (?0.57), micronaire versus fineness (0.82), strength versus 50 % span length (0.54), strength versus short fiber content (?0.69), and 50 % span length versus short fiber content (?0.78) while unfavorable additive correlations were not identified among fiber properties. These results indicated potential of simultaneous genetic improvement for these multiple properties in breeding populations derived from these germplasm lines. 相似文献
5.
G. Belay E. Bechere D. Mitiku A. Merker S. Tsegaye 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):221-228
Thirty‐four tetraploid (2n = 4x = 28) wheat (Triticum turgidum L.) landrace populations collected from four regions in Ethiopia, and consisting of 4099 entries were characterized for glume colour, glume pubescence, beak awn, seed colour and spike density. The main objective was to analyse the diversity and distribution of these traits on the basis of administrative regions and altitudinal gradients. The Shannon‐Weaver Diversity Index (H') was used to estimate the magnitude of diversity. With the exception of spike density, all characters were polymorphic in all regions and most altitude groups. However, clinal patterns were observed in only a few cases. At the population level, the mean H’ varied from completely monomorphic (H’ = 0.00) to highly polymorphic (H’ = 0.80 ± 0.07). The highest diversity was found in regions with relatively better climatic conditions and in optimal altitude ranges. On country basis, seed colour (H’ = 0.98) and spike density (H’ = 0.43) displayed the highest and the lowest diversity indices, respectively. Spike density was the only character that exhibited significant differences (P<0.01) both “between regions”; and “between altitude groups”;. Across characters, most of the variance was due to the lowest hierarchy, the “within‐population”; component. The “between region”; and “between altitude group”; variances were significant, but spike density alone was responsible for the differences. The overall mean H’ for Ethiopia was 0.77 + 0.09 and did not seem to have reduced appreciably within the past 25 years or so, when compared to previous estimates. 相似文献
6.
Use of chemical mutagenesis has been highly successful in most major crops. The objective of this research was to develop
‘naked-tufted’ seed mutants and to incorporate this genetic trait into cotton to enhance crop quality and reduce processing
costs. In 1997, six commercial cultivars were treated with 2.45% v/v ethyl methane sulfonate. In 1999, three M3 plants were identified that had partially naked seed coats. The trait was stabilized through individual plant selections
from 2000 to 2004. During 2005 and 2006, the homozygous naked-tufted M8 mutant lines were evaluated for lint yield, lint percent, fibers/seed, fibers/mm2, fiber quality, seed oil content, ginning efficiency and yarn spinning performance. Overall, the naked-tufted seed mutants
had lower lint yield, lower fibers/seed, lower lint/seed, and lower fibers/mm2 when compared with their original fuzzy parents. The lint turnout from the mutants was similar to the fuzzy parents and the
commercial cultivars. The naked-tufted seed mutants had higher seed oil percent, 6–17% lower short fiber contents, significantly
reduced seed coat neps (37–42%), higher elongation and yarn tenacity than their fuzzy counterparts. Preliminary data also
showed that the naked-tufted mutants required less energy to gin. 相似文献
7.
Efrem Gebrehawariat Berhan Tamir Azage Tegegne 《Tropical animal health and production》2010,42(8):1705-1710
Thirty-six Boran × Friesian dairy cows (392 ± 12 kg; mean ± SD) in early parity were used in a randomised complete block design.
Cows were blocked by parity into three blocks of 12 animals and offered normal maize (NM) stover (T1), NM silage (T2) or quality
protein maize (QPM) silage (T3) basal diets supplemented with a similar concentrate mix. Feed intake, body weight and condition
changes and milk yield and composition were assessed. The daily intake of DM, OM, NDF and ADF for cows fed the NM stover-based
diet was higher (P < 0.05) than for the cows fed the NM silage and QPM silage-based diets. However, the daily intake of DOM (9.3 kg) and ME
(140.8 MJ) for cows on QPM silage-based diet was higher (P < 0.05) than for cows on NM stover-based diet (8.4 kg and 124.2 MJ) and NM silage-based diet (7.9 kg and 119.1 MJ). Body
weight of cows was affected (P < 0.05) by the diet, but diet had no effect (P > 0.05) on body condition score, milk yield and milk composition. The digestible organic matter in the NM stover-based diet
(724 g/kg DM) was lower (P < 0.05) than that in the NM (770 g/kg DM) and QPM silage-based diet (762 g/kg DM). It was concluded that the performances
of the cows on the NM silage and QPM silage diets were similar and were not superior to that of the NM stover-based diet. 相似文献
8.
Summary Inheritance of seedling reactions to cultures of races TLM and MBCT of Puccinia graminis f.sp. tritici was studied in crosses of the resistant durum Reichenbachii with susceptible Marruecos 9623 and DZ04-118. The Chi-square test for goodness of fit was used to analyze segregating populations. Two independent recessive genes appeared to control resistance of Reichenbachii to both TLM and MBCT. Depending upon the cross, the two genes interacted cumulatively to condition immunity or higher levels of resistance than either parent conditioned singly. There was no evidence of maternal influence on the inheritance of resistance. Resistance genes in Reichenbachii were recessive; therefore, breeders should consider the use of relatively large F2 populations to effectively transfer these genes to cultivars with good agronomic characteristics. 相似文献
9.
Relationships between lint yield and within-boll yield components are important for genetic improvement of lint yield in cotton (Gossypium hirsutum L.) cultivars. F2 plants derived from crosses between germplasm lines and high yielding cultivars were analyzed to determine the contributions of within-boll yield components to lint yield and to select parents with desirable combining ability for multiple within-boll yield components. Forty-five F2 hybrids were planted at two field sites in 2010 and 2011 with 4 and 3 replicates, respectively. There were a total of six yield components analyzed including lint percentage (LP), seed number per boll, lint weight per seed (LW_S), seed surface area per seed, lint weight per unit seed surface area (LW_SA), and lint number per unit seed surface area (LN_SA). The contributions of these yield components to lint yield were analyzed by commonality analysis that separated the contributions to lint yield into the unique contributions of single yield components and the common contributions of the single yield components with one or more other yield components. The unique contributions of the six yield components to lint yield ranged from 1.6 to 21 % of total variation for lint yield in the 2-year experiments. The greatest common contributions to lint yield among all combinations of the six yield components were identified for a combination of four components, LP, LW_S, LW_SA, and LN_SA with 67 and 44 % of the total variation of lint yield in 2010 and 2011, respectively. Results suggest that all four of these yield components should be considered simultaneously in breeding for genetic improvement of lint yield. The germplasm line SP225 was detected as a good combiner with positive general combining ability (GCA) for LP (1.4 %), LW_SA (0.03 mg mm?2), and LN_SA (14.3 no mm?2), and favorable GCA for fineness (?3.1 mg km?1). 相似文献
10.
Tesfaye Tesemma Seifu Tsegaye Getachew Belay Efrem Bechere Demissie Mitiku 《Euphytica》1998,102(3):301-308
Plant breeding has always been concerned with genotype-environment interaction. Normally high and stable performance are desirable
attributes of cultivars. However, this is practically difficult to achieve where environmental variations are high and unpredictable
and significant genotype-environment interactions occur. Stability of performance of 13 landraces evaluated at 4 different
locations for 3 years in the highlands of Ethiopia was investigated. The testing locations have different climatic and edaphic
conditions providing the conditions necessary for the assessment of stability. Stability parameters like b, s2d, s2, r2 and cv which are in common use were employed. Grain yield and 1000-kernel weight were the agronomic traits considered for
the stability analysis. There were differences in the ranks of genotypes across the locations. Significant main environmental
as well as interaction effects were observed showing the importance of genotype-environment interaction in both traits. Many
of the landraces evaluated are rated as stable for these traits within the environmental conditions prevailing in these highland
locations. Genotypes with specific adaptation to poor and favourable conditions were also identified. Certain genotypes showed
similar manners of adaptation and stability for both of the traits. Grain yield showed low correlations with the stability
parameters showing the possibility of attaining high yield and stability. Correlations between the stability parameters were
mainly positive and significant for grain yield. Only a few of these correlations were found to be significant for kernel
weight. The good adaptability of landraces should be exploited in the improvement of their yield potential.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献