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991.
15个小麦重组自交系群体抗纹枯病性的遗传分析 总被引:5,自引:1,他引:5
为了研究小麦抗纹枯病性的基因控制,利用15个小麦重组自交系群体(RIL)在4个主基因鉴别模型(Ⅰ、Ⅱ、Ⅲ、Ⅳ)下对抗纹枯病性进行了遗传分析。结果表明,不符合正态分布的群体能在表现型水平上检测到主基因的存在,符合正态分布的群体也能在表现型水平上检测到主基因的存在,所分析的群体都是由主基因和微效基因共同控制的;符合4种主基因鉴别模型的情况都存在,模型Ⅳ即2对主基因相斥型连锁占总群体的比例较大;在2对主基因存在时,均有主基因间的互作效应,其值一般小于加性效应;主基因对变异的平均贡献为58%,比微效基因的贡献率大。 相似文献
992.
利用两系法配制玉米不育杂交种。应具备条件是:(1)不育系抗病性强;(2)所采用的不育系应归属C群;(3)不一育系应持有较多的保持系。研究指出,按照不育系双保持特性,利用掺和法配制杂交种。本文还就利用不育化单交种组配三交种、制种产量高的原因和恢复系的利用做了讨论。 相似文献
993.
Electroless metal plated fabrics are favorable to be used as e-textiles due to the excellent conductivity and peculiar properties
of textiles such as flexibility. But, the electrical durability is not enough to be used as e-textiles. Therefore, we applied
polyurethane(PU)-sealing (single-sealing vs. double-sealing) onto the electroless metal plated polyester fabrics (Ripstop
vs. Mesh) to reinforce the electrical durability. We investigated the changes of electrical properties of the PU-sealed metal
plated fabrics after laundering by a multi-meter, examined the surface changes using scanning electron microscope, and checked
the metal existence using energy dispersive X-ray spectroscopy. And, we finally proved the possibility of the fabric strips
as transmission lines by alternating conventional earphone lines. PU double-sealing showed higher performance on Ripstop polyester
fabrics even after being laundered 10 times, which was almost the same as Cu-based typical conductive lines did. 相似文献
994.
Elisa Sandra Tanaka de Farias José Carlos Pintro Maria Anita Gonçalves da Silva Antonio Saraiva Muniz Marlene Estevão Marchetti Antonio Nolla 《Journal of plant nutrition》2013,36(3):465-475
The objective of the present study was to evaluate the phytotoxic effect of aluminum (Al) in corn plants in nutrient solution under high ionic strength (0.0094 uM) and low ionic strength (0.00001 uM). Regarding the low ionic strengths, nutrient solution was added daily until the end of the experimental period. The findings showed that the pH of the nutrient solution reduced with the increase in Al concentration, under both high and low ionic strengths solutions. Electrical conductivity of the nutrient solution increased with Al concentrations only in the solution with low ionic strength, demonstrating that the plant was more sensible to the element toxicity, thus reducing its growth and absorption of nutrients. The production of the total dry mass of corn was affected by the increase of Al concentration in the solution only under low ionic strengths, which reinforces the greater activity and absorption of the element under such condition. 相似文献
995.
Wild relatives of wheat may possess useful traits or genes for efficient use of nitrogen (N) or phosphorus (P). Forty-three wheat addition lines with alien chromosomes from Leymus, Agropyron, Hordeum, Psathyrostachys, Aegilops, and Secale cereale, along with their common parent Chinese Spring (CS) were cultured by hydroponics, and their phenotypic variation, N/P uptake and utilization efficiency were investigated at seedling stage. The phenotypic variation showed that N deficiency decreased plant height, shoot dry weight, and total dry weight, while increased root length, number of leaves, SPAD value, and root to shoot ratio (R/S); while P deficiency decreased all the measured traits except root dry weight and R/S. Aegilops longissima 2S and Aegilops searsii 4SS addition lines were identified as both N- and P-efficient germplasm, of which Ae. longissima 2S addition line showed significant increased N and P uptake efficiency than CS under all treatments. 相似文献
996.
《Soil Science and Plant Nutrition》2013,59(5):734-744
Abstract The objective of the present study was to clarify the influence of volcanic ash addition on soil carbon stocks and the carbon accumulation process in brown forest soils (BFS) in Japan. The degree of volcanic ash addition to the soil was estimated according to the acid ammonium oxalate extractable aluminum (Alox) and lithic fragment contents, and their vertical distribution patterns. The BFS was classified in order of increasing volcanic ash influence on the soil into the following types: high Alox content with no gravel (H-Alox-NGv), high Alox with a high gravel content (H-Alox-Gv), moderate Alox (M-Alox), and low Alox (L-Alox), and then analyzed for carbon content, carbon amount, carbon stock, Alox amount and pyrophosphate extractable aluminum (Alpy) amount. The correlation between the carbon and Alpy amounts and the relationship between the Alpy and Alox amounts in the BFS samples indicated that the amount of carbon is determined by Al—humus complex formation, which is defined by the active Al generated from additional volcanic ash in BFS soil samples of BFS. Therefore, soils with thicker horizons and greater amounts of Alox had higher carbon levels in deeper horizons. For this reason, soil carbon stocks at depths of 0–30 cm and 0–100 cm, and in the effective soil depth of BFS, were larger and followed the order H-Alox-NGv = H-Alox-Gv > M-Alox > L-Alox. Furthermore, successive accumulations of volcanic ash on the soil surface promoted soil carbon accumulation as a result of the development of the surface horizon in H-Alox-NGv BFS. Our results suggest that volcanic ash additions control the soil carbon accumulation of forest soil in Japan. 相似文献
997.
土壤磷水平对柱花草株高、根长及生物量的影响 总被引:3,自引:0,他引:3
通过对8个柱花草品种(系)进行4个不同磷水平处理,在收获前对柱花草的生长情况进行调查,分别测量其株高、主根长和单株生物量,研究土壤磷水平对柱花草株高、根长及生物量的影响,旨在初步筛选耐低磷的柱花草品种(系)。结果表明:随着施磷量的减少,各柱花草品种(系)的平均株高、主根长和单株生物量总体呈下降趋势。其中,1号品种即西卡柱花草最耐低磷,5号品种即热研5号柱花草较耐低磷,7号柱花草即GC1463品系最不耐低磷。 相似文献
998.
999.
Chengfu Su Wei Wang Xinmian Qiu Liu Yang Song Li Meixing Wang Qunbin Pan 《Plant Breeding》2013,132(6):725-730
An initial F2 mapping population of 223 plants of the cross between TM‐1 (Gossypium hirsutum L.) × H102 (Gossypium barbadense L.) was used to map QTLs controlling fibre strength in cotton. A genetic linkage map with 408 SSR markers was constructed with a total length of 3872.6 cM. Multiple‐QTL model of the software MapQTL version 5.0 was used to map QTLs related to fibre strength of the F2 : 3 population. QTL QFS‐D11‐1 conferring fibre strength was mapped between NAU2950 and NAU4855 on chromosome 21 (Chr. 21) which explained 23.4% of phenotypic variation. Introgressed lines (ILs), that is, IL‐D11‐1, IL‐D11‐2 and IL‐D11‐3 were obtained through marker‐assisted backcrossing in TM‐1 background. An F2 population of 758 plants derived from cross IL‐D11‐2 × TM‐1 was used for fine‐mapping QTL QFS‐D11‐1. QFS‐D11‐1 was mapped between markers NAU2110 and NAU2950, adjacent to its initial interval NAU2950–NAU4855 with phenotypic variation explaining 35.8%. QFS‐D11‐1 was further mapped to 0.6 cM from the flanking marker NAU2950. The results will give a basis for marker‐assisted selection of QFS‐D11‐1 in cotton breeding and to lay the foundation for cloning QFS‐D11‐1. 相似文献
1000.
利用人工接种SRBSDV(Southern rice black-streaked dwarf virus)和采用高效液相色谱技术(High Performance Liquid Chromatography,HPLC)测定内源激素的研究方法,对SRBSDV胁迫下高抗SRBSDV水稻光温敏不育系1S和高感SRBSDV水稻光温敏不育系10S两个不同抗性不育系水稻幼苗植株内源激素赤霉素(GA3)、生长素(IAA)、水杨酸(SA)和脱落酸(ABA)的动态变化进行了研究.结果表明:1)人工接种SRBSDV后,促进生长类的激素GA3、IAA在10S处理植株中含量平均值显著低于其对照植株,在第5和第6天感病症状开始出现时达到最低值;在1S处理植株中IAA含量平均值显著低于其对照植株,GA3含量平均值也低于对照植株,但未达到5%显著水平.2)抗御信号分子SA在处理植株中含量平均值显著高于对照植株,在感病症状开始出现时,其含量都达到最高值,但10S在最高值后开始较快下降,而1S的SA含量则保持显著高于对照植株的水平.3)与衰老、死亡有关的内源激素ABA在处理植株中含量高于对照植株,10S的ABA含量显著高于1S,与其对照植株差异显著;1S与其对照差异不显著.4)SRBSDV胁迫改变了植株体内IAA/ABA和GA3/ABA的平衡.结论:SRBSDV胁迫改变了不育系内源激素含量,但这种变化究竟是由病毒侵染直接造成的,还是病毒诱导了细胞损伤或影响了水稻光温敏不育系同化作用后所造成的,还有待深入研究. 相似文献