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31.
Two new loci for hybrid sterility in cultivated rice (Oryza sativa L.) 总被引:17,自引:0,他引:17
J. Wan Y. Yamaguchi H. Kato H. Ikehashi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(2):183-190
Female gamete abortion in Indica-Japonica crosses of rice was earlier identified to be due to an allelic interaction at the S-5 locus on chromosome 6. Recently, in other crosses of rice, similar allelic interactions were found at loci designated as S-7 and S-8, located on chromosomes 7 and 6 respectively. All of them are independent of each other. At the S-5 locus, Indica and Japonica rice have S-5
i
and S-5
j
alleles respectively and Javanicas, such as Ketan Nangka, have a neutral allele S-5
n
.The S-5
i
/S-5
j
genotype is semi-sterile due to partial abortion of female gametes carrying S-5
j
, but both the S-5
n
/S-5
i
and S-5
n
/S-5
j
genotypes are fertile. The S-5
n
allele is thus a wide-compatibility gene (WCG), and parents homozygous for this allele are called wide-compatible varieties (WCV). Such parents when crossed with Indica or Japonica varieties do not show F1 hybrid sterility. Wide-compatible parents have been used to overcome sterility barriers in crosses between Indica and Japonica rice. However, a Javanica variety, Ketan Nangka (WCV), showed typical hybrid sterility when crossed to the Indian varieties N22 and Jaya. Further, Dular, another WCV from India, showed typical hybrid sterility when crossed to an IRRI line, IR2061-628-1-6-4-3(IR2061-628). By genetic analyses using isozyme markers, a new locus causing hybrid sterility in crosses between Ketan Nangka and the Indicas was located near isozyme loci Est-1 and Mal-1 on chromosome 4, and was designated as S-9. Another new locus for hybrid sterility in the crosses between Dular and the IR2061-628 was identified and was found linked to four isozyme loci, Sdh-1, Pox-2, Acp-1 and Acp-2, on chromosome 12. It was designated as S-15. On the basis of allelic interactions causing female-gamete abortion, two alleles were found at S-9, S-9
kn
in Ketan Nangka and S-9
i
in N22 and Jaya. In the heterozygote, S-9
kn
/S-9
i
, which was semisterile, female gametes carrying S-9
kn
were aborted. The hybrid of Dular and IR2061-628, with a genetic constitution of S-15
Du
/S-15
i
, was semi-sterile and the female gametes carrying S-15
Du
were aborted. A Japonica tester variety, Akihikari, and an Indica variety, IR36, were found to have neutral alleles, S-9
nand S-15
n, at these loci, in addition to S-7
nand at S-7. The accumulation of three neutral alleles into a breeding line should help solve the hybrid sterility problem in wide crosses of rice. 相似文献
32.
汉滩病毒核壳蛋白(NP)在杆状病毒系统的表达及其免疫原性研究 总被引:11,自引:0,他引:11
应用杆状病毒表达载体成功地表达了汉滩病毒76-118株(HTNV)核壳蛋白,将HTNVS基因插入杆状病毒转染质粒pAcYMIB的多角体基因启动子下游附近,与经Bsu361酶切线性化的杆状病毒(AcVEPA)DNA共同转染S19细胞,经空斑筛选获得了高效表达NP的重组杆状病毒(AcVHanS)。经SDS-PAGE和Western blot证实,表达产物与HTNV毒粒NP分子量均为50KD左右,紫外扫 相似文献
33.
34.
寡糖素对红花及三七培养细胞的生理作用 总被引:5,自引:0,他引:5
三种寡糖素,即来自人参(Panax ginseng)培养细胞的人参寡糖素、红花(Carthamus tinctorius)培养细胞的红花寡糖素、黑节草(Dendrobium candidum)植物的黑节草寡糖素对红花及三七(Panax notoginseng)的培养细胞的生长及代谢产物的含量均有显著的促进作用。寡糖素可耐高温高压(121℃、.bs/cm^2)灭菌15分钟而不失活,其对植物培养细胞的 相似文献
35.
棉铃虫致病菌BT—931菌株的应用研究 总被引:1,自引:0,他引:1
1992-1993年,作者从菏泽、聊城棉田采集的自然罹病死亡棉铃虫幼虫体内,分离到2个较高毒效的Bt菌株,编号为BT—931和BT—021,经室内毒力测定和田间药效试验表明,防效及保蕾效果接近或超过化学农药,菌药混剂3—5天平均防治效果达87.0-91.6%,增效作用显著。经1994年大田防治示范表明,利用BT—931菌剂。配合化学农药防治棉铃虫,具有成本低、保护天敌、持效期长、增产效益高等优点。本研究对菌剂的田间应用技术进行了试验示范。 相似文献
36.
用透明因法和福林──酚法筛选了21种植物中的蛋白酶活性抑制剂,其中来自鼓皮、高粱、玉米和土豆的抑制剂的活性在本研究条件下达50%以上。进一步研究了麸皮、玉米两种抑制剂在不同温度和pH值下的稳定性,结果表明,两者的稳定性相差甚远,是两类不同的抑制剂。玉米抑制剂比麸皮抑制剂更稳定。 相似文献
37.
Soo Wan Nam Byung Moon Kim Bong Hyun Chung Dae Ook Kang Jong Seog Ahn 《Biotechnology letters》1994,16(9):897-902
Summary For the secretion of human lipocortin-1 (LC-1) in yeast, a expression and secretion vector was constructed by using the promoter and signal sequence of glucoamylase gene (STA1) of Saccharomyces diastaticus. After the cDNA of human LC-1 was ligated with the secretion vector, the resulting hybrid plasmid was transformed into S. diastaticus. When the recombinant S. diastaticus was cultivated in YPD medium, LC-1 was expressed and secreted into the extracellular medium, yielding LC-1 protein at a concentration of 2.5 g/mL. 相似文献
38.
人参寡糖素对三七悬浮培养细胞生长的效应 总被引:4,自引:0,他引:4
从人参培养细胞的细胞壁中分离纯化到不同分子量的单体人参寡糖素。试验结果表明命名为人参寡糖素Ⅶ和人参寡糖素Ⅷ的两种寡糖素对三七悬浮培养细胞的生长具有明显的促进作用,其增长率分别为19.34%和10.58%,人参寡糖素Ⅶ的适宜浓度为5—10mg/l。在高浓度下(大于25mg/l)稍抑制培养细胞生长。在细胞培养22天(指数生长期)后.加入10mg/l的人参寡糖素Ⅶ.然后再培养2天。其生长速率即提高,加入人参寡糖素Ⅷ后.缩短了三七细胞悬浮培养生长的延缓期.提前进入对数生长期和指数生长期,并在对数生长期和指数生长期作用最明显,因而最终收获时培养细胞的产率增加。 相似文献
39.
40.