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111.
红凤菜红色素水溶液的稳定性试验 总被引:8,自引:1,他引:7
从红凤菜(Gynura bicolor DC.)地上部分提取了红色素水溶液。在350-700nm范围内的扫描结果显示,该色素有2个吸收峰,位于543nm和598nm附近。在pH2.2-6.0的范围内色素较稳定。加热使其吸收峰值增大,但波长基本不变。0.2mmol/L Fe^3 引起色素溶液变色并产生大量沉淀;Al^3 也能使其产生沉淀;Cu^2 对该色素的影响较小;Zn^2 、对其无影响。氧化剂(H2O2)与还原剂(Na2SO3)均能使该色素褪色。光照对该色素无明显影响。 相似文献
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114.
交配系统是影响植物种群遗传结构的重要因素之一,测定植物的交配系统不仅可以了解物种的繁殖格局,而且也有助于预测生境条件发生变化(如生境片断化)时物种遗传结构的变化趋势。红凉伞是常绿阔叶林伴生小灌木,雌雄同花。采用水平切片淀粉凝胶电泳法分析种子萌发幼苗的基因型,结合Ritland异交率估算模型(MLT),测定了浙江天童国家森林公园红凉伞的交配系统,共采用了3个酶位点(Adh-1,Fe-2和Amp-2)。两个红凉伞种群的异交率均大于1,分别为1.055和1.159,可能是由于处理过程中将小的集群合并处理的结果,因为小集群内家系数量少,无法计算异交率。计算的家系异交率大多很大,只是在小集群内存在异交率低的家系,表明当红凉伞聚生形成的集群内开花个体数少时,异交率将降低。分析了常绿阔叶林片断化对红凉伞种群交配系统的影响。 相似文献
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116.
CO2 enrichment increases water-use efficiency in sorghum 总被引:3,自引:1,他引:2
117.
G. E. Hart K. F. Schertz Y. Peng N. H. Syed 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,103(8):1232-1242
Grain yield of Sorghum bicolor (L.) Moench is significantly influenced by genetically controlled variation in the number of tillers, plant height, time
of anthesis, and various other morphological and physiological characters. In this study, a minimum of 27 unique QTLs that
control variation in nine morphological traits, including the presence versus the absence and the height of basal tillers,
were mapped, and the percentage of additive genetic variance explained by the QTLs was determined in a population of 137 recombinant
inbred lines in two environments. Four QTLs explained from 86.3% to 48.9% (depending upon the environment) of the additive
genetic variance in the number of basal tillers with heads, and seven QTLs explained from 85.9% to 47.9% of the additive genetic
variance in panicle width. It is unlikely that different alleles were segregating in the mapping population at any of the
major dwarfing loci, but five QTLs that explained from 65.8% to 52.0% of the additive genetic variance in main-culm height
were mapped. QTLs controlling variation in height of the tallest basal tiller, number of basal tillers per basal-tillered
plant, panicle length, leaf angle, maturity, and awn length also were mapped. Three or more QTLs were mapped in linkage groups
A, E, G, and I, while none were mapped in linkage groups B and D. Several of the QTLs mapped in this study are likely candidates
for marker-assisted selection in breeding programs.
Received: 20 September 2000 / Accepted: 26 October 2000 相似文献
118.
Molecular mapping of the rf1 gene for pollen fertility restoration in sorghum (Sorghum bicolor L.) 总被引:5,自引:0,他引:5
R. R. Klein P. E. Klein A. K. Chhabra J. Dong S. Pammi K. L. Childs J. E. Mullet W. L. Rooney K. F. Schertz 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(8):1206-1212
We report the molecular mapping of a gene for pollen fertility in A1 (milo) type cytoplasm of sorghum using AFLP and SSR marker
analysis. DNA from an F2 population comprised of 84 individuals was screened with AFLP genetic markers to detect polymorphic DNAs linked to fertility
restoration. Fifteen AFLP markers were linked to fertility restoration from the initial screening with 49 unique AFLP primer
combinations (+3/+3 selective bases). As many of these AFLP markers had been previously mapped to a high-density genetic map
of sorghum, the target gene (rf1) could be mapped to linkage group H. Confirmation of the map location of rf1 was obtained by demonstrating that additional linkage group-H markers (SSR, STS, AFLP) were linked to fertility restoration.
The closest marker, AFLP Xtxa2582, mapped within 2.4 cM of the target loci while two SSRs, Xtxp18 and Xtxp250, flanked the rf1 locus at 12 cM and 10.8 cM, respectively. The availability of molecular markers will facilitate the selection of pollen fertility
restoration in sorghum inbred-line development and provide the foundation for map-based gene isolation.
Received: 22 August 2000 / Accepted: 18 October 2000 相似文献
119.
Extrapair paternity and egg hatchability in tree swallows: evidence for the genetic compatibility hypothesis? 总被引:8,自引:5,他引:3
Kempenaers Bart; Congdon Brad; Boag Peter; Robertson Raleigh J. 《Behavioral ecology》1999,10(3):304-311
Tree swallows (Tachycineta bicolor) show one of the highestlevels
of extrapair paternity in birds, and there is evidencethat females have
control over who fathers their offspring.However, it is unclear which
benefits female tree swallows obtainfrom mating with multiple males. Using
microsatellite DNA fingerprinting,we studied extrapair paternity in relation
to nesting successand male, female, and offspring characteristics. More than
70%of all nests contained extrapair young, and more than half ofall
offspring were extrapair. Within broods, the extrapair youngwere often
fathered by several males. Despite screening allresident and some floater
males, we could identify the biologicalfather of only 21% of all extrapair
offspring. All identifiedextrapair males were close neighbors. Extrapair
males did notdiffer from within-pair males in any of the measured
characteristics,except that the former had larger cloacal protuberances than
thelatter. Extrapair males were equally successful in gaining paternityin
their own broods as males that did not father extra young.In nests with mixed
paternity, extrapair young did not differfrom within-pair young in body size
or mass. However, nestswith extrapair young had higher hatching success than
nestswithout extrapair young. All examined unhatched eggs were fertilizedand
thus hatch failure resulted from embryo mortality. The availabledata are in
accordance with the genetic diversity and the geneticcompatibility
hypothesis, but not with the good genes hypothesis. 相似文献
120.
NaCl胁迫对高粱根、叶鞘和叶片液泡膜ATP酶和焦磷酸酶活性的影响 总被引:13,自引:0,他引:13
NaCl胁迫初期 ,Na 主要在根和叶鞘中积累。相应地 ,根和叶鞘液泡膜ATP酶和焦磷酸酶水解活性、依赖ATP和PPi的质子泵活性及Na /H 逆向转运活性均明显增加 ,根和叶鞘的生长没有受到抑制。NaCl胁迫后期 ,Na 开始向地上部分运输并在叶片中积累。此时 ,叶片液泡膜质子泵和Na /H 逆向转运活性开始增加 ,根和叶鞘的Na/K比增加 ,其液泡膜ATP酶和焦磷酸酶水解活性、质子泵活性和Na /H 逆向转运活性下降。相应地 ,根和叶鞘的生长也下降。当保温介质中Na/K比超过 1时 ,液泡膜微囊ATP酶和焦磷酸酶活性均随Na/K比的增加而下降。表明非盐生植物液泡膜质子泵在盐胁迫的初期对Na 在液泡内的积累及其耐盐性起重要作用 相似文献