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921.
Hartmut H. Hilger Mechtild Balzer Wolfgang Frey Dieter Podlech 《Plant Systematics and Evolution》1985,148(3-4):291-312
Microparacaryum (M. Pop. exH. Riedl)Hilger & Podlech is described as a new genus of theBoraginaceae-Cynoglosseae. It comprises the annual species hitherto included inParacaryum (DC.)Boiss. andMattiastrum (Boiss.)Brand. Distribution maps are given for all 3 genera.Microparacaryum consists of two species,M. salsum (Boiss.)Hilger & Podlech (M. s.) andM. intermedium (Fresen.)Hilger & Podlech (M. i.). ParticularlyM. i. is a very variable species, and most of the species formerly recognized belong here. Scattered all over the range of the genus, plants occur with nutlets exhibiting flat or incurved marginal wings, often in mixed populations. This fruit polymorphism is taxonomically treated by recognizing formae. In addition, the following new infraspecific taxa and combinations are described:M. i. var.intermedium formaparacaryoides
Hilger & Podlech,M. i. var.stellatum (H. Riedl)Hilger & Podlech,M. i. var.stellatum formamattiastroides
Hilger & Podlech,M. s. formamattiastroides
Hilger & Podlech. 相似文献
922.
钟纪育 《植物分类与资源学报》1985,7(2):1-3
本文阐述樟科木姜子属及山胡椒属两者在形态、分布、起源及演化等方面有许多共同之处,不仅在属内具有平行演化的情况,而且各自平行演化成单花木姜子属 Dodecade-nia和单花山胡椒属Iteadaphne。同时两者又分别自4药室的拟擦术属Parasassafras和2药室的黄脉擦术属 sinosassafras演化而来。本文将单花木姜子亚属 Litsea subg.Uniflos Yang et P.H.Huang归人单花木姜子属,并把 Litsea monantha Yang et P.H.Hu-ang一种作为单花木姜子(原变种)Dodecadenia grandiflora Nees var.grandiflora的新异名,恢复了单花山胡椒属Iteadaphne Bl.,并将香面叶Lindera caudata(Nees)Hook·f.重新组合归入该属为Ⅰ.caudata(Nees)H.W.Li,comb.nov。此外,本文还发表了一个新属即黄脉擦木屑 Sinosassafras H.W.Li,gen.nov.,它具有2药室花药而不同于其平行演化的拟擦本属。 相似文献
923.
Spondias mombin supplementation attenuated cardiac remodelling process induced by tobacco smoke 下载免费PDF全文
Maria Angélica Martins Lourenço Mariana Gobbo Braz Aline Garcia Aun Bruna Letícia Buzati Pereira Amanda Menezes Figueiredo Renata Aparecida Cândido da Silva Elisa Moya Kazmarek Patrícia Helena Correa Alegre Tatiana Fernanda Bachiega Silmeia Garcia Zanati Paula Schmidt Azevedo Bertha Furlan Polegato Ana Angélica Henrique Fernandes Sergio Alberto Rupp de Paiva Leonardo Antonio Mamede Zornoff Marcos Ferreira Minicucci 《Journal of cellular and molecular medicine》2018,22(8):3996-4004
The objective of this study was to investigate the influence of Spondias mombin (SM) supplementation on the cardiac remodelling process induced by exposure to tobacco smoke (ETS) in rats. Male Wistar rats were divided into 4 groups: group C (control, n = 20) comprised animals not exposed to cigarette smoke and received standard chow; group ETS (n = 20) comprised animals exposed to cigarette smoke and received standard chow; group ETS100 (n = 20) received standard chow supplemented with 100 mg/kg body weight/d of SM; and group ETS250 (n = 20) received standard chow supplemented with 250 mg/kg body weight/d of SM. The observation period was 2 months. The ETS animals had higher values of left cardiac chamber diameters and of left ventricular mass index. SM supplementation attenuated these changes. In addition, the myocyte cross‐sectional area (CSA) was lower in group C compared with the ETS groups; however, the ETS250 group had lower values of CSA compared with the ETS group. The ETS group also showed higher cardiac levels of lipid hydroperoxide (LH) compared with group C; and, groups ETS100 and ETS250 had lower concentrations of LH compared with the ETS group. Regarding energy metabolism, SM supplementation decreased glycolysis and increased the β‐oxidation and the oxidative phosphorylation. There were no differences in the expression of Nrf‐2, SIRT‐1, NF‐κB, interferon‐gamma and interleukin 10. In conclusion, our results suggest that ETS induced the cardiac remodelling process. In addition, SM supplementation attenuated this process, along with oxidative stress reduction and energy metabolism modulation. 相似文献
924.
Small but attractive: female‐biased nectar production and floral visitors in a dimorphic shrub 下载免费PDF全文
- In sexually dimorphic species, hermaphrodite flowers in gynodioecious species or male flowers in dioecious species are often larger and produce more nectar than their conspecific female flowers. As a consequence, hermaphrodite or male flowers frequently receive more pollinator visits.
- Sex ratio, flower size, floral display, nectar production and floral visits were evaluated in two natural populations of Fuchsia thymifolia, a morphologically gynodioecious but functionally subdioecious insect‐pollinated shrub.
- Sex ratio did not differ from the expected 1:1 in the two studied populations. As expected, hermaphrodite flowers were larger than female flowers, but in contrast to the general pattern, hermaphrodite flowers did not produce nectar or produced much less than female flowers. Flower visitors were flies (68%) and bumblebees (24%), both of which showed a preference for female flowers. No sex difference was detected in either flower longevity or floral display across the flowering season.
- Higher nectar production by females may attract more pollinators, and may be a strategy to enhance female reproductive success in this species. Finally, floral dimorphism and insect preferences did not seem to hamper the maintenance of sub‐dioecy or prevent the evolution of dioecy in F. thymifolia.
925.
Fruit Softening: Revisiting the Role of Pectin 总被引:3,自引:0,他引:3
926.
927.
Herbarium specimens show patterns of fruiting phenology in native and invasive plant species across New England 下载免费PDF全文
Amanda S. Gallinat Luca Russo Eli K. Melaas Charles G. Willis Richard B. Primack 《American journal of botany》2018,105(1):31-41
Premise of the Study
Patterns of fruiting phenology in temperate ecosystems are poorly understood, despite the ecological importance of fruiting for animal nutrition and seed dispersal. Herbarium specimens represent an under‐utilized resource for investigating geographical and climatic factors affecting fruiting times within species, patterns in fruiting times among species, and differences between native and non‐native invasive species.Methods
We examined over 15,000 herbarium specimens, collected and housed across New England, and found 3159 specimens with ripe fruits, collected from 1849–2013. We examined patterns in fruiting phenology among 37 native and 18 invasive woody plant species common to New England. We compared fruiting dates between native and invasive species, and analyzed how fruiting phenology varies with temperature, space, and time.Key Results
Spring temperature and year explained a small but significant amount of the variation in fruiting dates. Accounting for the moderate phylogenetic signal in fruiting phenology, invasive species fruited 26 days later on average than native species, with significantly greater standard deviations.Conclusions
Herbarium specimens can be used to detect patterns in fruiting times among species. However, the amount of intraspecific variation in fruiting times explained by temporal, geographic, and climatic predictors is small, due to a combination of low temporal resolution of fruiting specimens and the protracted nature of fruiting. Later fruiting times in invasive species, combined with delays in autumn bird migrations in New England, may increase the likelihood that migratory birds will consume and disperse invasive seeds in New England later into the year. 相似文献928.
Effect of exposure time on mass‐rearing production of the olive fruit fly parasitoid,Psyttalia lounsburyi (Hymenoptera: Braconidae) 下载免费PDF全文
M. La‐Spina C. Pickett K. M. Daane K. Hoelmer A. Blanchet L. Williams 《Journal of Applied Entomology》2018,142(3):319-326
Classical biological control programmes rely on mass production of high‐quality beneficial insects for subsequent releases into the field. Psyttalia lounsburyi (Silvestri) (Hymenoptera: Braconidae) is a koinobiont larval–pupal endoparasitoid of tephritid flies that is being reared to support a classical biological control programme for olive fruit fly in California. The mass‐rearing system for a P. lounsburyi colony, initiated with insects originally collected in Kenya, was evaluated with the goal of increasing production, while at the same time reducing time requirements for rearing in a quarantine facility. We tested the effect of exposure time of a factitious host Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), on parasitization, adult production, superparasitism, and sex ratio of P. lounsburyi and survival of the host. Parasitization rates were highest (31%) at 3‐ and 4‐hr exposure times, while adult production (i.e., emergence of wasp progeny) was highest (16%) at the 2‐hr exposure time. Superparasitism over the course of the study was 1.5% and did not appear to be a factor affecting parasitoid production. The sex ratio of wasp progeny was male‐biased and did not vary significantly over different exposure times. The rate of stings on host larvae increased with exposure time and was consistent with decreases in pupal eclosion from larvae and emergence rate of adult flies. When compared to current rearing procedures, the 2‐hr exposure time resulted in an overall 2.8‐fold increase in P. lounsburyi production when standardized for time. 相似文献
929.
For genetic linkage analysis of Japanese flounder, 160 doubled haploids (DH) were artificially produced using mitotic gynogenesis and were genotyped for 458 simple sequence repeat (SSR) markers, 101 of which show distortional segregation. The genetic linkage map was constructed by modifying recombination fractions between the distorted markers. Between the corrected and uncorrected genetic maps, there were considerable differences in genetic distance, but not in relative locations among markers. Using a liability model, a segregation distortion locus (SDL), with an additive genetic effect of 1.772, was mapped between markers BDHYP387 and Poli56TUF of chromosome 24 in the corrected genetic map. Additionally, six pairs of epistatic SDLs were identified on chromosomes 1, 5, 8, 9, 23, and 24. Changes in genetic distances between markers did not occur on chromosome regions with main effect SDLs. However, most chromosome regions where genetic distances changed covered the detected epistatic SDLs. This study concluded that epistatic SDLs decrease linkages between markers and lengthen genetic distances in Japanese flounder. This finding has been partially validated in other DH populations derived from three female Japanese flounders. 相似文献
930.
该研究对云南省广南县不同分布点的野生植株大小与结实量,果实、果核性状特征,果皮与果核性状间的关系进行了分析。结果表明:(1)野生成年植株个体间结实量差异大,单株结实量从几十个至几千个,变异系数可达136.38%。结实量与冠幅有正相关关系(R=0.592,P0.01),与胸径和树高无相关关系(P0.05)。(2)扁球型果实平均纵径37.10~40.36 mm,变异系数7.28%~8.65%;平均横径41.15~45.03mm,变异系数6.44%~9.31%;平均果实重量35.77~47.29 g,变异系数18.99%~21.44%。野生蒜头果果实大小差异明显,单个果实重量差别为3.4倍。(3)果核平均纵径27.50~31.69 mm,变异系数7.13%~10.99%;平均横径30.94~34.16 mm,变异系数6.47%~9.41%;平均果核重量14.03~18.77 g,变异系数17.37%~22.68%。单个果核重量差别为3.7倍。(4)平均果皮纵向厚度4.33~4.80 mm,变异系数20.22%~26.91%;平均横向厚度5.10~5.44 mm,变异系数12.92%~20.98%;平均果皮重21.62~28.51 g,变异系数20.01%~24.12%。该研究结果表明野生蒜头果单株结实量、果实和果核大小、果皮厚等表型性状存在广泛的多样性,其资源为人工定向培育和开发利用提供了较为丰富的选择材料。 相似文献