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981.
N. K. Sheeba B. C. Viraktamath S. Sivaramakrishnan M. G. Gangashetti Pawan Khera R. M. Sundaram 《Euphytica》2009,167(2):217-227
The present study was carried out with the objective to validate the molecular markers, which have been previously reported
to be linked to fertility restorer (Rf) gene(s) for WA-CMS lines of rice. Two mapping populations involving fertility restorer lines for WA-cytoplasm, viz., (i)
an F2 population derived from the cross IR58025A/KMR3R consisting of 347 plants and (ii) a BC1F1 population derived from the cross IR62829A/IR10198R//IR62829A consisting of 130 plants were analyzed. Nine SSR and three
CAPS markers reported to be linked to Rf genes along with two previously unreported SSR markers were analyzed in the mapping populations. In both the populations
studied, the trait of fertility restoration was observed to be under digenic control. Eight SSR markers (RM6100, RM228, RM171,
RM216, RM474, RM311, MRG4456 and pRf1&2) showed polymorphism between the parents of the F2 population, while the SSR markers RM6100 and RM474 showed polymorphism between the parents of both the F2 and BC1F1 populations. Only one CAPS marker, RG146FL/RL was polymorphic between the parents of the BC1F1 population. RM6100 was observed to be closely segregating with fertility restoration in both the mapping populations and
was located at a distance of ~1.2 cM. The largest phenotypic variation was accounted for the region located between RM311
and RM6100. Using the marker-trait segregation data derived from analysis of both the mapping populations, a local linkage
map of the genomic region around Rf-4, a major fertility restoration locus on Chromosome 10 was constructed, and RM6100 was observed to be very close to the gene
at a distance of 1.2 cM. The accuracy of the marker RM6100 in predicting fertility restoration was validated in 21 restorers
and 18 maintainers. RM6100 amplified the Rf-4 linked allele in a majority of the restorers with a selection accuracy of 94.87%. Through the present study, we have established
the usefulness of the marker RM6100 in marker-assisted selection for fertility restoration in segregating populations and
identification of restorers while screening rice germplasm for their fertility restoration ability. 相似文献
982.
There is no information in the literature about the variability of resistance of Chinese Brassica vegetables, pak choi and Chinese cabbage, to the white blister disease caused by Albugo candida (Pers.) Kuntze. A collection of 43 accessions of pak choi and 19 accessions of Chinese cabbage was screened for resistance to the Portuguese A. candida isolate Ac 506 at the cotyledon stage. Different levels of resistance were found among the germplasm tested, ranging from complete resistance to full susceptibility. Most of the accessions were highly susceptible with less than 10% of resistant seedlings, and only four accessions of pak choi, presenting more than 50% resistant seedlings, were considered as new sources or resistance to white blister. Inheritance of resistance at the cotyledon stage was studied in two crosses between the most resistant pak choi accession, BRA 117, and the highly susceptible rapid cycling Brassica rapa line CrGC 1.19. It was proposed that resistance to white blister in pak choi BRA 117 is controlled by two nuclear genes with dominant recessive epistatic gene action. 相似文献
983.
984.
介绍了鲜切果蔬的概念、历史、优点、加工工艺及操作技术要点,概述了不同鲜切条件对果蔬生理生化及品质的影响,加工与保鲜过程中微生物污染,褐变机理及营养成分变化等,提出了防止褐变发生及延长保鲜期的具体方法,并探讨了果蔬鲜切和保鲜现状及发展趋势。 相似文献
985.
986.
高压矩形脉冲电场果蔬预处理微观结构变形机理的研究 总被引:2,自引:0,他引:2
基于电磁力学理论,结合苹果单细胞模型,研究其性状的变化,获得了HPEF作用果蔬的微观机理。研究显示,HPEF处理果蔬的效果与物料性质有关,不同物料预处理显著程度不同,主要是由于不同物料的细胞参数以及其结构引起力学性质的改变不同;HPEF处理作用强度越大,细胞膜受到的应力也越大。 相似文献
987.
988.
989.
Wild service tree [Sorbus torminalis (L.) Crantz] is a forest tree widespread in Europe, characterized by a scattered distribution. Its hermaphroditic flowers
are pollinated by insects, and outcrossing is the prominent mating system, also due to the presence of gametophytic self-incompatibility.
Genetic diversity and differentiation of 22 populations from northwestern Italy were investigated by means of variation scored
at 53 polymorphic RAPD (Random Amplified Polymorphic DNA) loci. Populations differed in genetic variation, with Shannon diversity
index ranging from 0.166 to 0.469. According to Analysis of Molecular Variance (AMOVA), most of the genetic variation was
found within populations (61.78%) with a significant proportion of variance attributable to genetic differences between regions
(23.60%) and between populations (14.62%). Evidence for isolation by distance was found in the set of populations sampled.
The effect of habitat fragmentation on genetic variation was also evaluated. The efficacy of RAPD markers in analysing genetic
variation, and the contribution of the results in terms of the preservation of biodiversity are discussed. 相似文献
990.
野生鸭茅生育特性多样性研究 总被引:2,自引:0,他引:2
[目的]系统研究野生鸭茅生长发育特性。[方法]对从我国野生鸭茅主要分布区和国外收集的35份野生鸭茅种质的生育特性进行研究。[结果]早熟型在拔节期前后进入生长高峰期,日均增长速度最快为1.93 cm/d,生育期为249 d,营养、生殖生长期分别为199、50 d;缓慢生长型在整个生长期间的生长速度都极为缓慢,在试验区只有营养生长,而无生殖生长;晚熟型在孕穗期生长速度最快,生育期为289 d,营养、生殖生长分别需251和38 d;中熟型介于早、晚熟型之间;早熟型具有营养生长期比中、晚熟型短,而生殖生长期比中、晚熟型长的特点,前者开花~成熟期要比后两者分别长9和13 d;晚熟型成熟期株高显著高于早、中熟型。[结论]野生鸭茅种质生育特性呈现多样性变异。 相似文献