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81.
L.-H. Zhang P. Ozias-Akins G. Kochert S. Kresovich R. Dean W. Hanna 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(6-7):895-902
Bermudagrasses (Cynodon spp.) are major turfgrasses for home lawns, public parks, golf courses and sport fields, and are widely adapted to tropical
and warmer temperate climates. Morphological and physiological characteristics are not sufficient to differentiate some bermudagrass
genotypes because the differences between them are often subtle and subject to environmental influence. In this study, a DNA-typing
technique, amplified fragment length polymorphism (AFLP), was used to differentiate bermudagrass genotypes and to explore
their genetic relationships. Twenty seven bermudagrass cultivars and introductions, mostly from the Coastal Plain Experiment
Station in Tifton, Ga., were assayed by the radioactive (32P) and the fluorescence-labeled AFLP methods. The AFLP technique produced enough polymorphism to differentiate all 27 bermudagrass
genotypes, even the closely related ones. An average of 48–74 bands in the 30–600-bp size range was detected by the 32P-labeled AFLP method. The results indicated that most of the 14 primer combinations tested in this study could be used to
distinguish bermudagrass genotypes, and that some single primer-pairs could differentiate all 27 of them. To test the reliability
and reproducibility of the AFLP procedure, three DNA isolations (replications) of the 27 bermudagrass genotypes were assayed
using five primer pairs. Only 0.6% of the bands were evaluated differently among the three replications. One replication of
one genotype (which was most likely a planting contaminant) was grouped in an unexpected cluster using the Unweighted Pair
Group Mean Average (UPGMA) method. A one- or two-band difference in scoring did not change the clustering of genotypes or
the replications within genotypes. The 27 genotypes were grouped into three major clusters, many of which were in agreement
with known pedigrees. Trees constructed with different primer combinations using 32P- and fluorescence-labelling formed similar major groupings. The semi-automated fluorescence-based AFLP technique offered
significant improvements on fragment sizing and data handling. It was also more accurate for detection and more efficient
than the radioactive labelling method. This study shows that the AFLP technique is a reliable tool for differentiating bermudagrass
genotypes and for determining genetic relationships among them.
Received: 28 July 1998 / Accepted: 3 November 1998 相似文献
82.
Keizo Yonemori Chitose Honsho Shinya Kanzaki Hitofumi Ino Ayako Ikegami Akira Kitajima Akira Sugiura Dan E. Parfitt 《Tree Genetics & Genomes》2008,4(2):149-158
To elucidate the relationships among Diospyros kaki and species closely related in previous studies, the nuclear ribosomal internal transcribed spacer (ITS) DNA sequence and
the chloroplast matK gene were sequenced and compared with those of nine Diospyros species from Thailand, four species from temperate regions, and one species of southern Africa, D. lycioides. Maximum parsimony, maximum likelihood, and neighbor joining analyses of the matK and ITS data sets revealed that D. kaki is closely related to two diploid species, D. oleifera and D. glandulosa. D. kaki, D. glandulosa, and D. oleifera were placed differently in the trees obtained from ITS and matK data sets, suggesting that hybridization and/or introgression may have occurred during the development of these species.
D. kaki was not found to be closely related to D. ehretioides, a diploid species from Thailand. These results differed from a prior analysis of this genus performed with chloroplast DNA
(cpDNA) restriction site mutations in 3.2- and 2.1-kb amplified sequences. The results supported Ng’s hypothesis that D. glandulosa and D. kaki may share a common ancestor. D. oleifera was also closely associated with D. kaki. 相似文献
83.
Dermacentor reticulatus and D. marginatus exhibit overlapping phenotypes. The possibility of conspecificity was investigated on the nucleotide level by comparing DNA sequences of the second internal transcribed spacer (ITS 2) of the rDNA gene. The inter-specific polymorphism was more than 20-times greater than the intra-specific polymorphism of 3 D. reticulatus strains of different geographic origins. Furthermore, the degree of polymorphisms between D. reticulatus and D. marginatus was found to be of the same order of magnitude as that between D. andersoni and D. variabilis, for which separate species status is accepted. These genomic findings do not support a possible conspecificity of D. reticulatus and D. marginatus. 相似文献
84.
A study of the mycobiota in the digestive tract of 5 important species of triatomines, Triatoma brasiliensis, T. infestans, T. sordida, T. pseudomaculata and T. vitticeps, was made. The digestive tracts of 164 adults and 535 nymphs of those triatomines were studied and 393 fungal strains were isolated.The genera with the greatest number of species were Penicillium (19 species), Aspergillus (17 species) and Acremonium (5 species) and the most frequent species, in decreasing order, were Penicillium corylophilum, Aspergillus niger, Penicillium fellutanum, Cladosporium herbarum, Penicillium waksmanii, Aspergillus awamori and Paecilomyces variotii. Among the isolated fungi, we found species that are recognized as entomopathogenic and pathogenic for humans and animals.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
85.
86.
Bahiagrass,Corn, Cotton Rotations,and Pesticides for Managing Nematodes,Diseases, and Insects on Peanut 总被引:1,自引:0,他引:1
A. W. Johnson N. A. Minton T. B. Brenneman G. W. Burton A. K. Culbreath G. J. Gascho S. H. Baker 《Journal of nematology》1999,31(2):191-200
Florunner peanut was grown after 1 and 2 years of Tifton 9 bahiagrass, corn, cotton, and continuous peanut as whole-plots. Pesticide treatments aldicarb (3.4 kg a.i./ha), flutolanil (1.7 kg a.i./ha), aldicarb + flutolanil, and untreated (control) were sub-plots. Numbers of Meloidogyne arenaria second-stage juveniles in the soil and root-gall indices of peanut at harvest were consistently lower in plots treated with aldicarb and aldicarb + flutolanil than in flutolanil-treated and untreated plots. Percentages of peanut leaflets damaged by thrips and leafhoppers were consistently greater in flutolaniltreated and untreated plots than in plots treated with aldicarb or aldicarb + flutolanil but not affected by cropping sequences. Incidence of southern stem rot was moderate to high for all chemical treatments except those that included flutolanil. Stem rot loci were low in peanut following 2 years of bahiagrass, intermediate following 2 years of corn or cotton, and highest in continuous peanut. Rhizoctonia limb rot was more severe in the peanut monoculture than in peanut following 2 years of bahiagrass, corn, or cotton. Flutolanil alone or combined with aldicarb suppressed limb rot compared with aldicarb-treated and untreated plots. Peanut pod yields were 4,186 kg/ha from aldicarb + flutolanil-treated plots, 3,627 kg/ha from aldicarb-treated plots, 3,426 kg/ha from flutolanil-treated plots, and 3,056 kg/ha from untreated plots. Yields of peanut following 2 years of bahiagrass, corn, and cotton were 29% to 33% higher than yield of monocultured peanut. 相似文献
87.
Heinz Duewell 《Biochemical Systematics and Ecology》1997,25(8):717-738
It was found that the composition of the resins produced by members of the genus Xanthorrhoea was sufficiently taxon-specific to allow the setting up of a chemotaxonomic key. A generalized procedure for the isolation of flavanoids from Xanthorrhoea resins is given together with details of all isolated components. 相似文献
88.
Viviane Fátima de Oliveira Lucas Figueiredo Gabriel de Oliveira Correia Maria de Fátima Pires da Silva Machado Hugo Zeni Neto Wanderley Dantas dos Santos Claudete Aparecida Mangolin 《Global Change Biology Bioenergy》2023,15(12):1465-1476
The burgeoning cellulosic ethanol industry necessitates advancements in enzymatic saccharification, effective pretreatments for lignin removal, and the cultivation of crops more amenable to saccharification. Studies have demonstrated that natural inhibitors of lignin biosynthesis can enhance the saccharification of lignocellulose, even in tissues generated several months post-treatment. In this study, we applied daidzin (a competitive inhibitor of coniferaldehyde dehydrogenase), piperonylic acid (a quasi-irreversible inhibitor of cinnamate 4-hydroxylase), and methylenedioxy cinnamic acid (a competitive inhibitor of 4-coenzyme A ligase) to 60-day-old crops of two conventional Brazilian sugarcane cultivars and two energy cane clones, bred specifically for enhanced biomass production. The resultant biomasses were evaluated for lignin content and enzymatic saccharification efficiency without additional lignin-removal pretreatments. The treatments amplified the production of fermentable sugars in both the sugarcane cultivars and energy cane clones. The most successful results softened the most recalcitrant lignocellulose to the level of the least recalcitrant of the biomasses tested. Interestingly, the softest material became even more susceptible to saccharification. 相似文献
89.
中国特产雉类—褐马鸡,藏马鸡和蓝马鸡卵壳的电镜观察 总被引:12,自引:4,他引:12
迄今为止,在国内有关野生鸟类卵壳的超微结构报道尚少。我们对中国特产鸡类——三种马鸡卵壳的表皮、气孔、木栅层、锥体层、乳头结、壳膜和基帽进行了扫描巨镜观察,并对结果进行了比较、讨论。认为三种马鸡不同结构的形态,对研究它们的亲缘关系提供了新的价值。 相似文献
90.
The anticancer agent miltefosine and the antifungal drug voriconazole were tested in vitro against Balamuthia mandrillaris, Acanthamoeba spp., and Naegleria fowleri. All three amebas are etiologic agents of chronic (Balamuthia, Acanthamoeba) or fulminant (Naegleria) encephalitides in humans and animals and, in the case of Acanthamoeba, amebic keratitis. Balamuthia exposed to <40 microm concentrations of miltefosine survived, while concentrations of >or=40 microM were generally amebacidal, with variation in sensitivity between strains. At amebastatic drug concentrations, recovery from drug effects could take as long as 2 weeks. Acanthamoeba spp. recovered from exposure to 40 microM, but not 80 microM miltefosin. Attempts to define more narrowly the minimal inhibitory (MIC) and minimal amebacidal concentrations (MAC) for Balamuthia and Acanthamoeba were difficult due to persistence of non-proliferating trophic amebas in the medium. For N. fowleri, 40 and 55 microM were the MIC and MAC, respectively, with no trophic amebas seen at the MAC. Voriconazole had little or no inhibitory effect on Balamuthia at concentrations up to 40 microg/ml, but had a strong inhibitory effect upon Acanthamoeba spp. and N. fowleri at all drug concentrations through 40 microg/ml. Following transfer to drug-free medium, Acanthamoeba polyphaga recovered within a period of 2 weeks; N. fowleri amebas recovered from exposure to 1 microg/ml, but not from higher concentrations. All testing was done on trophic amebas; drug sensitivities of cysts were not examined. Miltefosine and voriconazole are potentially useful drugs for treatment of free-living amebic infections, though sensitivities differ between genera, species, and strains. 相似文献