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131.
Xiaohan Sun Feng Wang Rong Cui Xiao Liu Xiangxiang Li Jibin Dong Lu Sun Siqi Qin Renqing Wang Peiming Zheng Hui Wang 《Ecology and evolution》2020,10(12):5270-5280
Vitex negundo L. var. heterophylla (Franch.) Rehder (Lamiaceae) is an important tree species for soil and water conservation, yet the reproductive ecology of this species remains to be elucidated. To investigate the reproductive traits of V. negundo var. heterophylla, the phenology, morphological characteristics (a suite of characters was assessed: floral morphology, nectar production, pollen viability, and stigma receptivity) and mating system of this species were systematically revealed for the first time in this study. Phenological observations, morphological measurements, and nectar production analysis were conducted during anthesis. Pollen viability and stigma receptivity at different flowering stages were measured by biochemical methods. Finally, genetic analysis based on SSR markers was used to reveal the mating system; outcrossing index and pollen‐ovule ratio were also calculated to help analysis. V. negundo var. heterophylla showed several obvious characteristics of outcrossing, such as abundant and attractive flowers, secreting nectar, and emitting scent. In addition, mechanisms such as homogamy and a short anther‐stigma distance that can promote self‐fertilization were also identified in this species. The coexistence of selfing and outcrossing characteristics demonstrates a predominantly outcrossed mixed mating system (outcrossing rate, t = 95%). The scientific information provided by this study may contribute to conservation of V. negundo var. heterophylla from a reproductive perspective. 相似文献
132.
Sambucus adnata Wall. belongs to Caprifoliaceae family. Phytochemical investigation on the aerial parts of S. adnata led to the isolation and identification of 17 known compounds (1–17) including triterpenoids and sterols. Compounds 1 and 8 are isolated from Sambucus adnata for the first time, and it is the first report that compounds 2, 5–6, 9–10, 12–15, and 17 are isolated from the plants of genus Sambucus. Importantly, three types of abundant components: (3β)-urs-12-en-3-yl stearate (0.33 g/kg, ursane type), (3β)-olean-12-en-3-yl stearate (0.17 g/kg, oleanane type), and lupenyl palmitate (0.52 g/kg, lupinane type) could be used as potential chemotaxonomic markers to distinguish among species of Sambucus. 相似文献
133.
This review summarizes the flavonoids isolated from three genera, namely, Aconitum, Delphinium, and Consolida, belonging to tribe Delphineae in the Ranunculaceae family for the first time. A total of 104 distinct flavonoid components, including 85 flavonols, 13 anthocyanins, four flavones, and two neoflavones, have been isolated from 44 members of tribe Delphineae. Flavonols account for the largest proportion and can be regarded as the dominant group of flavonoids in this tribe. Of the 104 isolated flavonoids, 55 are novel, indicating the high chemical diversity among the flavonoid constituents of Delphineae plants. Flavonoids in Delphineae plants exhibit chemotaxonomic significance, characterizing certain Delphineae species well. Flavonol glycosides, as the major flavonoid constituents in the investigated Delphineae species, could also serve as valuable chemotaxonomic markers in addition to diterpenoid alkaloids for the identification of Delphineae species. 相似文献
134.
Teer Eman Joseph Danzil E. Dominick Leanne Glashoff Richard H. Essop M. Faadiel 《中国病毒学》2021,36(5):1133-1143
Virologica Sinica - Although antiretroviral treatment lowers the burden of human immunodeficiency virus (HIV)-related disease, it does not always result in immunological recovery. This manifests as... 相似文献
135.
136.
Monika Sodhi M. Mukesh B. P. Mishra S. P. S. Ahlawat B. Prakash R. C. Sobti 《Animal biotechnology》2013,24(1):16-29
The present study aims to understand the existing genetic diversity and structure of six native cattle breeds (Rathi, Tharparkar, Nagori, Mewati, Gir, and Kankrej) adapted to the north-western arid and semi-arid region of India based on microsatellite loci. Various diversity estimates, mean number of alleles (12.84); effective number of alleles (5.02); gene diversity (0.769), and observed heterozygosity (0.667) reflected the existence of substantial within-breed diversity in all the investigated cattle breeds. Mean estimates of F-statistics: FIT = 0.144 ± 0.023, FIS = 0.071 ± 0.021, and FST = 0.078 ± 0.014 were significantly different from zero (P < 0.05). The interbreed relationships indicated moderate level of breed differentiation between the six cattle breeds with least differentiation between Kankrej-Mewati pair. The phylogeny structuring further supported close grouping of Kankrej and Mewati breeds. Correspondence analysis plotted Rathi, Tharparkar, and Gir individuals into three separate areas of multivariate space; whereas, Kankrej, Mewati, and Nagori cattle showed low breed specific clustering. This reflected the existence of discrete genetic structure for Tharparkar, Rathi, and Gir, the prominent dairy breeds of the region; whereas, admixture was observed for Kankrej, Mewati, and Nagori individuals. 相似文献
137.
The present study was conducted to assess the genetic diversity, population structure, and relatedness in Indian red jungle fowl (RJF, Gallus gallus murgi) from northern India and three domestic chicken populations (gallus gallus domesticus), maintained at the institute farms, namely White Leghorn (WL), Aseel (AS) and Red Cornish (RC) using 25 microsatellite markers. All the markers were polymorphic, the number of alleles at each locus ranged from five (MCW0111) to forty-three (LEI0212) with an average number of 19 alleles per locus. Across all loci, the mean expected heterozygosity and polymorphic information content were 0.883 and 0.872, respectively. Population-specific alleles were found in each population. A UPGMA dendrogram based on shared allele distances clearly revealed two major clusters among the four populations; cluster I had genotypes from RJF and WL whereas cluster II had AS and RC genotypes. Furthermore, the estimation of population structure was performed to understand how genetic variation is partitioned within and among populations. The maximum ?K value was observed for K = 4 with four identified clusters. Furthermore, factorial analysis clearly showed four clustering; each cluster represented the four types of population used in the study. These results clearly, demonstrate the potential of microsatellite markers in elucidating the genetic diversity, relationships, and population structure analysis in RJF and domestic chicken populations. 相似文献
138.
Abstract Recent work, based on morphological and cytotaxonomical information, claimed the independence of Plantago brutia Ten., a narrow endemic of South Italy, with respect to Plantago media L. Here, we present a further evaluation of the systematic relationships occurring between these two taxa as revealed by molecular studies. We sampled P. brutia in most of the known populations and P. media in several European stands, from Sweden to the Iberian Peninsula and Balkans. We then investigated the relationships among the sampled populations by using as molecular markers the internal transcribed spacer regions ITS1 and ITS2. Furthermore, we considered cpDNA to gain further insight into the relationships among P. brutia/P. media populations. Based on nrDNA data, P. brutia appeared to be nested within the P. media complex, but as a well distinct subunit. This is congruent with a subspecific rank for this taxon within P. media. The cpDNA revealed the occurrence of several haplotypes in the studied material. Most of the assessed haplotypes were exclusive for single populations and thus phylogenetically uninformative. Nonetheless, we have found some haplotypes that are shared by different cytotypes or populations throughout the species range, suggesting possible explanations for the phylogenetic relationships occurring between P. brutia and the autopolyploid complex P. media. 相似文献
139.
Marek Banasik † Todd Stedeford † Amanda S. Persad Kunihiro Ueda Seigo Tanaka Carlos Muro-Cacho 《Journal of enzyme inhibition and medicinal chemistry》2013,28(6):551-555
Adult male ICR mice were treated by intraperitoneal injection with 250?mg/kg of bodyweight of commercial malathion (a dose corresponding to 1/12 the LD50). After 6?h, acetylcholinesterase (AChE) activity in blood, liver, and six brain regions was determined. A statistically significant inhibition was observed in whole blood (23%), liver (21%), and, in particular, the central nervous system; the greatest degree of AChE inhibition was observed in the cerebellum (45%), followed by the hippocampus (29%). There was no significant change in AChE activity in the caudate putamen, frontal cortex, midbrain, or pons medulla. These results demonstrate that the magnitude of AChE inhibition in peripheral tissues does not accurately reflect the central-inhibitory effects of malathion on AChE activity in specific brain regions. 相似文献
140.