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91.
 利用聚丙烯酰胺凝胶电泳(SDS-PAGE)方法,在蛋白质水平上对多个亲本及其杂交获得的正反交F1代杂交籽粒进行小麦高分子量谷蛋白亚基(HMW-GS)分析,研究其遗传规律。结果表明:小麦高分子量谷蛋白亚基具有品种特性,表达受遗传控制, 不受环境影响;小麦高分子量谷蛋白亚基在F1代有些组合呈共显性,有些组合呈倾母性的遗传特性。  相似文献   
92.
Bacterial leaf blight of rice (BLB), caused by Xanthomonas oryzae pv. oryzae, is one of the most destructive diseases in Asian rice fields. A high-quality rice variety, LT2, was used as the recipient parent. IRBB21, which carries the Xa21 gene, was used as the donor parent. The resistance gene Xa21 was introduced into LT2 by marker-assisted backcrossing. Three Xoo races were used to inoculate the improved lines following the clipping method. Eleven BC3F3 lines carrying Xa21 were obtained based on molecular markers and agronomic performance. The 11 lines were then inoculated with the three Xoo races. All the 11 improved lines showed better resistance to BLB than the recipient parent LT2. Based on the level of resistance to BLB and their agronomic performance, five lines (BC3F3 5.1.5.1, BC3F3 5.1.5.12, BC3F3 8.5.6.44, BC3F3 9.5.4.1 and BC3F3 9.5.4.23) were selected as the most promising for commercial release. These improved lines could contribute to rice production in terms of food security.  相似文献   
93.
三白草属于三白草科,其花没有花萼和花瓣,开花时顶端三片苞片变白。A-class MADS-box基因在花发育过程中起着重要作用。APETALA1(AP1)基因属于花分生组织识别基因,调控花分生组织向花器官的转变;同时AP1基因又是花器官形态特征基因,在花发育的ABCDE模型中,AP1基因属于A类基因,是萼片和花瓣正常发育所必需的。本研究通过RACE方法克隆三白草的MADS-box AP1基因的cDNA全长并与其他物种的AP1同源基因C-末端的结构域进行比较,同时对AP1 MADS-box基因在苞叶变化过程中表达进行分析,无被花三白草的研究对正确了解花被起源和演化过程具有重要的意义。  相似文献   
94.
Lavandula stoechas L. plant is a perennial evergreen used as a fragrant ornamental and medicinal plant. In order to study the effect of foliar spray of zinc sulfate (ZnSO4) (0, 1000, and 2000 mgL?1) and sodium chloride (NaCl) salinity (0, 75, and 150 mM) on some physiological characteristics of Lavandula stoechas L. plants, a pot experiment was carried out at the Research Greenhouse of Azarbaijan Shahid Madani University, Iran. Physiological characteristics [root and leaf dry weights, total soluble solids (TSSs), total anthocyanins, chlorophyll b, Zn2+, potassium (K+) contents, and K+/Na+ ratio] were significantly affected by the interaction effects of ZnSO4 foliar application and salinity levels. The highest root dry weight, chlorophyll b, anthocyanin, and Zn contents as well as TSS were found in the plants with NaCl0 × ZnSO4 2000 mgL?1. For Na+, the greatest value was recorded with NaCl 150 × ZnSO40. The highest K+/Na+ ratio was found in the control plants. Foliar application of ZnSO4 promoted the total phenolic content, especially at 2000 mgL–1. The highest amounts of flower dry weights were recorded at NaCl0. Chlorophyll a, total flavonoids, stem dry weight, and essential oil content were affected with ZnSO4 treatment and salinity levels. The highest values for the essential oil content, chlorophyll a content, and stem dry weight were attained by the nonsaline treatment. Both foliar application levels positively influenced the essential oil and flavonoid contents of the plants. The results reveal that zinc application had marked effects on the physiological characteristics of Lavandula stoechas L. plants growing under salinity stress conditions.  相似文献   
95.
The present study compared six near-isogenic lines from different backgrounds, varying in Rht (reduced height) alleles for gibberellin (GA) response, for heat and drought tolerance. Various temperature (day/night: 20/12 °C to 39/31 °C), and irrigation (100% field capacity and no irrigation) treatments were imposed at booting stage. Results depicted a 50% reduction in grain yield at 36.7 °C with irrigation and at 31.2 °C without irrigation. Number of grains per spike was severely reduced over 26 °C for water-stressed plants while irrigated plants did not show any significant reduction up to 34 °C. Ear numbers per pot and spikelets per spike were unaffected by irrigation till 33 °C. In Mercia, grain nitrogen, sulphur, and Hagberg falling number (HFN) were significantly higher for severe dwarfs (Rht-D1c and Rht-12), however, in Maris Widgeon, rht (tall) recorded higher nitrogen and sulphur concentration while Rht-B1b presented the maximum sedimentation of sodium dodecyl sulphate (SDS). The SDS was higher in Maris Widgeon while HFN were superior in Mercia. Conclusively, the present study demonstrated that heat and drought stresses severely reduced the grain yield while improved grain quality traits. The GA-insensitive semi dwarf Rht-B1b was the most promising genotype for grain yield and HFN under combined drought and heat stresses.  相似文献   
96.
不同生育阶段气象因子对玉米产量及构成要素的影响分析   总被引:5,自引:3,他引:2  
为揭示气象因子对玉米产量构成要素的影响机理,以‘吉单27’为试验材料,于2012、2013年在佳木斯市农业气象试验站进行分期播种试验,通过调整播期改变玉米生育期内的气象条件,分析产量及产量构成要素与气象因子的关系,为抵御阶段性不良气象因子的胁迫并实现玉米高产提供理论依据。结果表明:产量构成要素与不同生育阶段的多个气象因子显著相关。拔节至大喇叭口期日均降水量为玉米产量的限制因子,通过影响秃尖比、穗粒数和株粒数重影响产量;吐丝至乳熟期温度为限制因子,该生育期随着日平均气温、日均最高温度、日均最低温度的升高,秃尖比减小,穗粒数、株粒数重均增加;大喇叭口至抽雄期,日照时数与秃尖比呈显著负相关,此期随着日照时数的增加秃尖比减小;乳熟到成熟期,日均相对湿度影响穗粒数、株粒数重的提升。‘吉单27’在佳木斯的最佳播种时间为5月上中旬,6月下旬至7月上旬的日均降水量,7月下旬至8月上旬的日平均气温、日均最高温度、日均最低温度成为玉米产量提升的限制因子,在试验设定的密度条件及栽培管理水平下,产量提升主要受穗粒数的制约。  相似文献   
97.
解淀粉芽孢杆菌B9601-Y2对玉米的防病促生长效果研究   总被引:8,自引:4,他引:4  
通过平板对峙培养及盆栽试验,研究解淀粉芽孢杆菌B9601-Y2(Y2)防治玉米小斑病和茎基腐病以及提高玉米生物量的效果。平板对峙培养结果表明,Y2发酵液、无菌滤液及菌体悬液对玉米小斑病菌和茎基腐病原菌均有拮抗作用。盆栽实验结果显示,3种处理对玉米小斑病防效60%左右,对茎腐病防效50%左右,防效依次为Y2发酵液菌体悬液无菌滤液。单独使用Y2发酵液、无菌滤液及菌体悬液处理的苗根长、株高、鲜重和干重均显著高于清水和病原菌对照20%以上,喷施或灌溉接种病原菌的玉米苗生长量显著高于单独接种病原菌处理,有效消除了病原菌对植株生长的影响。因此,生防菌Y2具有用于防治玉米病害和具有根肥及叶面肥的潜力。  相似文献   
98.
Cytoplasmic male sterility exists widely in most natural populations of welsh onion (Alliumfistulosum L.), which makes it possible to breed out many male sterile lines for heterosis utilization. Unfortunately, the breeding of cytoplasmic male sterility in welsh onion has a little progress due to the limitation of its biological characteristic and traditional selection approach. To study the feasibility and the efficiency of utilizing marker assisted selection for male sterile lines in welsh onion, one SCAR marker, SCS13, and one RAPD marker, S2002400, which could distinguish between N and S cytoplasm in several welsh onion cultivars, were identified. The two markers were then confirmed by Southern blotting, and used to screen the N or S cytoplasm of individual plants in seven welsh onion cultivars in this study. Male sterile and fertile plants were evaluated by aceto-carmine dying. The frequency of N-cytoplasmic plants and maintainer genotype was calculated in the seven open populations of welsh onion. The minimum number of plants needed to identify a maintainer was evaluated to be 95% reliable. Results showed that 20 to 80% decrease of crosses and self-crosses for identifying a maintainer genotype could be achieved by the marker-assisted selection compared with traditional selection method. It was proved that the molecular markers could precisely identify cytoplasmic types individually, performed by one generation of cross and two generations of testcrosses and self-crosses. Finally, several maintainer genotype plants were selected with the help of the two markers in the seven cultivars. The screened markers could assist and accelerate sterile and maintainer lines selection with less labor and cost.  相似文献   
99.
Phytic acid (PA) is the main storage organic form of phosphorus (P) in seeds of cereals and legumes. It is a strong inhibitor against the absorption of nutrients in monogastric animals. The objective of this study was to determine the variation of total P (TP) in seeds of mungbean germplasm and investigate the inheritance of seed P compound and phytate contents. TP content in seeds of 250 accessions were found to range from 2.34 to 5.75 mg/g. The inheritance was studied in the F2 population derived from a cross between 2 accessions with the lowest and highest PA contents, viz. V1658BBR and V1141BG. Broad-sense heritability estimates of TP, inorganic P (IP), and phytate P (PhyP) contents were 80.8, 78.6 and 80.7%, respectively. The 9:7 segregation ratio of F2 population in this study indicated that high TP and PhyP were controlled by dominant alleles at 2 independent loci of major genes showing duplicated recessive epistasis.  相似文献   
100.
核转录因子NF-κB与动物机体的炎症反应、免疫应答、细胞分化和凋亡等密切相关,而Toll样受体(TLR)通过对侵入机体的病原微生物的抗原识别和信号转导,在NF-κB介导的炎症和免疫应答反应中发挥着重要作用。本研究在新疆褐牛和荷斯坦牛隐性乳房炎调查和TLR4外显子3 +2021 位点(E3+2021)SNP基因型与隐性乳房炎相关性研究的基础上,分析和比较了E3+2021 SNP位点3种不同基因型奶牛个体NF-κB信号通路上9个基因(NFκB1、NFκB2、RelA、c-Rel、RelB、IKKα、IKKβ、IKKγ和IκBα基因)转录水平的差异。结果显示,在BB基因型中,NFκB1和IKKα基因的mRNA转录水平在新疆褐牛与荷斯坦牛品种间差异显著(P<0.05),RelA、RelB、IKKβ、IKKγ和IκBα基因mRNA转录水平在品种间差异极显著(P<0.01)。在AB基因型中,IκBα基因mRNA转录水平在品种间差异显著(P<0.05)。在对新疆褐牛的研究中发现,RelB、IKKγ和IκBα基因mRNA转录水平在AB和BB两种基因型间差异显著(P<0.05);而在荷斯坦牛检测的9个基因的mRNA转录水平在AB和BB两种基因型间差异均不显著。因此,Toll样受体信号转导通路下游NFκB1、RelA、IKKβ、IKKγ和IκBα基因的mRNA转录水平在品种间的变化,可能与新疆褐牛乳汁中体细胞数(SCS)显著低于荷斯坦牛相关。在新疆褐牛中,RelB、IKKγ和IκBα基因mRNA转录水平的变化可能是AA基因型SCS显著高于AB基因型的原因之一。  相似文献   
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