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991.
Genetic main effects and genotype × environment (GE) interaction effects for erucic acid content (EAC) in rapeseed(Brassica napus L.) were analyzed for two year data by using the genetic models and corresponding statistical approaches for quantitative
traits of diploid plant seeds. Eight parents were included in adiallel mating design in two environments. It was found that
the embryo, cytoplasmic and maternal main effects and their GE interaction effects could simultaneously affect the performance
of EAC, especially for the cytoplasmic and maternal effects. Since the amount of genetic main effects from the expression
of genes in different genetic systems accounted for about 64.1%of the total genetic effects, EAC of rapeseed was mainly controlled
by genetic main effects. The total narrow-sense heritability for EAC was 83.6% with the general heritability being 51.9% and
the interaction heritability being 31.7%. It was suggested by the predicted genetic effects, that Tower and Youcai 601 were
better than other parents for reducing EAC in rapeseed quality breeding.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
992.
Water Relations, Abscisic Acid and Yield of Wheat Plants in Relation to the Interactive Effect of Seawater and Growth Bioregulators 总被引:4,自引:0,他引:4
Irrigation of wheat plants with seawater (10 and 25 %) led to significant increases in free and bound abscisic acid (ABA) in leaves, especially at 25 %. The relative water content (RWC) and water use efficiency (calculated from grain yield, WUEG , or from biomass yield, WUEB ) of the seawater-irrigated plants were lower than those of the control. Grain pre-soaking in gibberellic acid (GA3 ), indole-3-acetic acid (IAA) or ABA reduced the levels of accumulated ABA (free and bound) produced by seawater irrigation. The stress imposed by seawater generally reduced yield and yield components of wheat plants and the effect was more pronounced at the higher level of seawater irrigation (25 %). Furthermore, seawater treatments decreased the carbohydrate content and increased the protein content of the developing grains. The effect of seawater treatments on ion concentrations in the developing grains was not consistent. The application of growth bioregulators appeared to mitigate the effect of seawater salinity stress on wheat productivity. GA3 was the most effective hormone in this regard. The economic yield (grain yield) had a strong positive correlation with RWC, WUEG , WUEB , plant height, shoot fresh and dry weight, grain number/main spike, kernel weight and harvest index. 相似文献
993.
Abscisic acid, gibberellin and cell viability in cereal aleurone 总被引:3,自引:0,他引:3
Paul C. Bethke Angelika Fath Yoav N. Spiegel Yong-sic Hwang Russell L. Jones 《Euphytica》2002,126(1):3-11
The aleurone layer of cereals is a secretory tissue whose activity is regulated by abscisic acid (ABA) and gibberellins (GAs).
Whereas GA triggers enzyme synthesis and secretion and initiates a program that culminates in cell death, ABA prevents enzyme
production and cell death. Reactive oxygen species (ROS) are key players in regulating cell viability and GA sensitizes the
aleurone cell to ROS. Sensitivity of GA-treated cells results in part from a reduction in steady-state amounts of mRNAs encoding
enzymes that scavenge ROS. mRNAs encoding catalase, superoxide dismutase and ascorbate peroxidase are almost undetectable
in aleurone layers 24 h after incubation in GA. For layers incubated in ABA, however, the amounts of these mRNAs increase.
Western blotting and enzyme activity assays confirm that GA but not ABA reduced the amount and activity of ROS scavenging
enzymes (Fath et al., 2001b). Substantial amounts of ROS are produced by enzymes engaged in lipid metabolism, and by the electron
transport chain in the mitochondria. Aleurone layers contain abundant stores of triglycerides and ROS are produced as these
lipids are rapidly converted to sugars. We hypothesize that the ROS produced in GA-treated aleurone cells bring about cell
death by disrupting the plasma membrane. Aleurone cells incubated in ABA, on the other hand, are better able to maintain redox
balance. ABA does not initiate rapid triglyceride metabolism, and the activities of ROS-scavenging enzymes remain high in
ABA-treated cells. We conclude that GA initiates a metabolic cascade in aleurone cells that results in death from ROS. ABA
maintains viability by keeping ROS under control.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
994.
Although the Advanced Backcross strategy has proven very useful for QTL detection in tomato, it has been used mainly in identifying
QTL for agronomic traits such as yield, color, etc. Tomato flavor is an important quality characteristic, yet it has been
difficult to assess flavor or traits that affect it. In this study the AB-QTL strategy was applied to four advanced backcross
populations to identify QTL for biochemical properties that may contribute to the flavor of processed tomatoes, such as sugars
and organic acids. A total of 222 QTL were identified for 15 traits, including flavor as assessed by a taste panel. Correlations
of certain biochemicals with flavor and possible methods of assessing and improving flavor are discussed. In particular, QTL
with very significant effects associated with the ratio of sugars/glutamic acid, a trait highly correlated with improved flavor,
have been identified as good targets for future work in improving the flavor of tomatoes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
995.
996.
东北地区大豆品种资源脂肪酸组成的分析研究 总被引:11,自引:1,他引:11
测定2341份我国东北地区大豆品种资源5种脂肪酸含量。以亚油酸含量最高,45—62%。平均含量依次为亚油酸>油酸>棕榈酸>亚麻酸>硬脂酸。分析比较结果,各脂肪酸含量,不同种皮色、脐色、结荚习性、叶形和花色品种间存在显著差异。棕榈酸、油酸、亚油酸和亚麻酸含量,不同栽培类型、不同粒形品种间有显著差异。硬脂酸、油酸和亚麻酸 相似文献
997.
A new sunflower mutant, CAS-12, was obtained, which has both high palmitic (≈30%) and high oleic acid contents, and also a
substantial amount of palmitoleic acid (≈7%). The mutant was selected after X-ray irradiation of dry seeds of the inbred line
BSD-2-423, which had normal palmitic (≈3%) and high oleic (≈88%) acid levels. The increase of palmitic and palmitoleic acids
occurred at the expense of the oleic acid content, which decreased to around 55% in respect to the original line. Linoleic
acid content is always under 5%. Palmitic and palmitoleic acid levels were similar to those of the high palmitic mutant CAS-5
obtained in a previous programme from a low oleic line isogenic to BSD-2-423 using a similar mutagenic treatment. In that
previous programme we also selected three high stearic acid mutants using chemical mutagenic treatment on the same sunflower
line (RDF-1-532). We attempted to obtain mutants in other lines but were unsuccessful. The isolation of similar mutants in
isogenic parental lines illustrates the importance of the genetic background in the development of specific mutants with an
altered seed oil fatty acid composition. The oil of this mutant will increase the range of potential uses of sunflower oil.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
998.
Genetic and environmental effects on abscisic acid accumulation in leaves of field-grown maize 总被引:1,自引:0,他引:1
Summary This study analyzes the components of phenotypic variation for abscisic acid (ABA) content in maize (Zea mays L.) leaves and the correlations with drought sensitivity index (DSI) and silk delay (SD), involved in the reaction to water deficit. Eight early- and seven medium-maturity inbreds were examined in field trials: in 1990 with low irrigation volume and in 1991 with low and high irrigation volumes. ABA concentration and DSI were investigated at growth stages (S) corresponding to stem elongation (S3), appearance of the first husks (S4), and mid-end of silking (S5). The ABA concentration was significantly higher in conditions of water deficit and in the later growth stage. The genetic component for ABA concentration attained higher relative values than those shown by DSI in the same growth stages and by SD; moreover, it increased from growth stage 3 to stage 5. The genotype × year and genotype × irrigation volume interactions were smaller for ABA concentration than for DSI and SD. The broad sense heritability on a plant basis, estimated in drought conditions, for ABA concentration ranged from 21.4 to 55.1% according to maturity group and growth stage. A wide variation was observed among lines for ABA concentration: the medium-maturity group showed a three-fold range (from 219 to 605 ng ABA g–1 dry weight). No clear relationships between ABA concentration, DSI and SD were found. These results indicate the feasibility of a selection for ABA concentration within segregating populations derived from crosses between the inbred lines herein tested.Abbreviations ABA -
abscisic acid
- DSI -
drought sensitivity index
- DW -
dry weight
- SD -
silk delay 相似文献
999.
水稻籽粒蛋白质、游离氨基酸含量的配合力与杂种优势分析 总被引:6,自引:2,他引:6
利用两组5×5双列杂交,以 Griffing模型Ⅰ分析籽粒蛋白质、游离氨基酸含量的配合力与杂种优势表现。结果表明:1.蛋白质、游离氨基酸含量均受加性和非加性基因效应的共同作用,但蛋白质以加性效应为主,游离氨基酸以非加性效应为主;2.蛋白质不存在显著的胞质效应,而游离氨基酸则存在极显著的胞质效应;3.蛋白质杂种优势较小,其最强的组合超中亲优势值仅为13.75%,而游离氨基酸存在强大的杂种优势,最高的组合可达155.17%;4.蛋白质、游离氨基酸一般配合力间存在极显著线性关系,在一般配合力改良上可同步进行; 5.京香1号、培矮64、IR58、Mcp231-2具有较高的一般配合力和较大的特殊配合力方差,可作为优良亲本利用。 相似文献
1000.
大麦DNA导入小麦诱导抗白粉病变异的研究 总被引:9,自引:2,他引:9
本试验利用外源DNA导入技术,研究了大麦DNA导入小麦品种后,D_1,D_2和D_3代的抗白粉病变异株(系)在不同条件下的抗性表现及产量构成、籽粒蛋白质和氨基酸含量的变化。试验结果表明,导入外源DNA的D_1代小麦檀株出。现了抗白粉病等多种变异类型,其中免疫和高抗白粉病变异株古2.77%,且抗性能够向子代传递,其D_2代在大田自然发病和温室接菌条件下,有5个株系抗性保持稳定,8个株系有分离,其中一个株系在D_2和D_3代抗性均稳定。在田间D_2代有2个稳定株系(D_2-20,D_2-29)的籽粒粗蛋白质含量,比受体分别高20.3%和15.76%,17种氨基酸总量分别高23.4%和27.5%。在温室这些性,状的数值也明显高于受体。 相似文献