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1.
以1年生毛竹实生苗为研究对象,研究多效唑对不同水分条件下毛竹实生苗的叶绿素含量、光合参数、非结构性碳水化合物(NSC)含量、碳氮比、根系活力的影响。设置3个水分梯度:W1(75%相对田间持水量,CK)、W2(50%相对田间持水量,中度干旱)和W3(35%相对田间持水量,重度干旱),以及2个多效唑浓度:P1(0mg/L)、P2(40mg/L)。结果表明:随干旱强度增加,P1W1、P1W2、P1W3处理叶色逐渐变淡。与对照P1W1相比,P1W2和P1W3处理下叶绿素a、叶绿素b、类胡萝卜素、叶绿素a/b和叶绿素总含量显著下降(P0.05),Pn、Tr、WUE显著下降(P0.05),Ls显著上升(P0.05),毛竹叶片及根系中非结构性碳水化合物(NSC)含量显著上升(P0.05),毛竹根系活力显著下降。多效唑处理后,P2W2和P2W3的叶片色素含量相对于P2W1显著提高,但P2W2与P2W3无显著差异。同时,施加多效唑使Pn显著提高,P2W3较P1W3增加了146.9%。此外,P2W3处理使可溶性糖大量积累,达最大值3.41mg/g;毛竹叶片及根系淀粉含量显著上升,根系活力显著提高。试验揭示了多效唑通过提高干旱水平下毛竹实生苗的根系活力、光合速率,增加光合色素、非结构性碳水化合物含量,并将养分从地上转移到地下部分,进而抵御干旱胁迫带来的伤害。  相似文献   

2.
Pleione ‘Frank Kingdon Ward’ first appeared in collections in the 1950s and has persisted. It has been considered to be a form of the spring flowered Pleione humilis but cytological examination shows it to be a triploid hybrid. Its identity is examined here and a formal hybrid name is proposed for it.  相似文献   

3.
Phylogenetic relationships among those yeast species that form saturn-shaped ascospores and which are assigned to the generaWilliopsis andPichia were estimated from their extent of nucleotide sequence divergence in three regions of ribosomal RNA. ThePichia species (P. dispora, P. saitoi, P. zaruensis andP. sp. nov.) are a closely clustered group only distantly related toWilliopsis, and it is proposed that they be reassigned toSaturnospora gen. nov. The extent of divergence amongWilliopsis species (W. californica, W. mucosa, W. pratensis, W. saturnus andW. sp. nov.) is greater than that previously observed within other ascomycetous yeast genera.  相似文献   

4.
Cytochrome c peroxidase (CcP) variants with an engineered Mn(II) binding site, including MnCcP [CcP(MI, G41E, V45E, H181D)], MnCcP(W191F), and MnCcP(W191F, W51F), that mimic manganese peroxidase (MnP), have been characterized by resonance Raman (RR) spectroscopy. Analysis of the Raman bands in the 200–700 cm–1 and 1300–1650 cm–1 regions indicates that both the coordination and spin state of the heme iron in the variants differ from that of CcP(MI), the recombinant yeast CcP containing additional Met-Ile residues at the N-terminus. At neutral pH the frequencies of the 3 mode indicate that a pure five-coordinate heme iron exists in CcP(MI) whereas a six-coordinate low-spin iron is the dominant species in the CcP variants with the engineered Mn(II) binding site. The H181D mutation, which weakens the proximal linkage to the heme iron, may be responsible for these spectral and structural changes. Raman spectra of the variants CcP(MI, W191F) and CcP(MI, W191F, W51F) were also obtained to clarify the structural and functional roles of mutations at two tryptophan sites. The W51F mutation was found to disrupt H-bonding to the distal water molecules and the resulting variants tended to form transitional or mixed coordination states that possess spectral and structural features similar to that of MnP. Such structural features, with a loosened distal water, may facilitate the binding of H2O2 and increase the rate constant for compound I formation. This effect, in addition to the elimination of an H-bond to ferryl oxygen by the same mutation, accounts for the increased MnP specific activity of MnCcP(W191F, W51F).Electronic Supplementary Material Supplementary material is available in the online version of this article at .Abbreviations CcP cytochrome c peroxidase - CcP(MI) recombinant yeast CcP containing Met-Ile at the N-terminus in addition to the normal wild-type CcP sequence - HRP horseradish peroxidase - MnCcP CcP(MI, G41E, V45E, H181D) - MnCcP(W191F) CcP(MI, G41E, V45E, H181D, W191F) - MnCcP(W191F, W51F) CcP(MI, G41E, V45E, H181D, W191F, W51F) - MnP manganese peroxidase - RR resonance Raman - WtCcP wild-type cytochrome c peroxidase  相似文献   

5.
Saturn-spored species assigned to the generaWilliopsis andPichia were compared from extent of nuclear DNA complementarity. Of thePichia spp., four were recognized as distinct taxa:P. dispora, P. saitoi, P. zaruensis andPichia sp. nov. AmongWilliopsis spp., the following were accepted:W. californica, W. mucosa comb. nov.,W. pratensis, W. saturnus var.saturnus, W. saturnus var.mrakii comb. nov.,W. saturnus var.sargentensis comb. nov.,W. saturnus var.subsufficiens comb. nov. andWilliopsis sp. nov. The newPichia andWilliopsis species are described elsewhere. Moderate (36–68%) DNA relatedness was detected between the formerPichia sargentensis and varieties ofW. saturnus again demonstrating that nitrate assimilation is not a reliable criterion for separating yeast species.  相似文献   

6.
In this paper, we propose that Rhododendron clementinae Forrest ex W. W. Sm. subsp. aureodorsale W. P. Fang ex J. Q. Fu should be recognized at species rank as Rhododendron aureodorsale (W. P. Fang ex J. Q. Fu) Y. P. Ma & J. Nielsen. This species is similar to R. clementinae, but has an isolated distribution range, and differs by having tawny indumentum without pellicle on the abaxial leaf surface, sparse hairs on both pedicel and sepals, and always 7 corolla lobes.  相似文献   

7.
Callicarpa peichieniana W. Y. Chun & S. L. Chen ex W. Z. Fang’ is a replacement name for Premna peii W. Y. Chun ex H. T. Chang. However, this replacement name was not validly published in 1982 by W. Z. Fang because the reference citation of the replaced synonym P. peii that was published in 1960 was contrary to Article 33.4 of ICBN. The first publication of Premna peii in 1960 was invalid due to lack of type indication, in conflict with Article 37.1, and it was subsequently validated in 1963. In this study, we correct the place of valid publication of P. peii, thereby validating C. peichieniana W. Y. Chun & S. L. Chen ex H. Ma & W. B. Yu.  相似文献   

8.
Cloned highly repeated DNA sequences were used to investigate the origins of W. virgo. The chromosomal and genomic organization of these sequences in the parthenogenetic grasshopper W. virgo and its sexual relatives indicate that W. virgo has had two independent origins. Data from the cloned sequences together with that from rapidly renaturing DNA are consistent with a hybridization event between two sexual species for each origin of the parthenogenetic species. Previously published data on C-banding and other karyotypic features (White and Contreras 1981) strengthen the dual origin conclusion. — The cloned DNA sequences, pWv 1 and pWv 5, have differentiated northern and southern races in the sexual species P196. The southern race appears to have hybridized with another sexual species, P169, to give rise to the Boulder/Zanthus clones of W. virgo. The northern race of P196 may have crossed with a species similar to P169 to give rise to the remaining W. virgo clones which are now present in both eastern and western Australia. White (1980) proposed that the origin of W. virgo was in western Australia and that the eastern populations were established by migration. Consistent with this hypothesis is our finding that the cloned DNA sequences have identical genomic and chromosomal organisation in populations of W. virgo in the two disjunct areas.Respectfully dedicated to Professor Wolfgang Beermann on his 60th birthday, in recognition of his great contributions to modern cytogenetics  相似文献   

9.
The aim of this study was to examine the relationships between the characteristics of anaerobic exercise in the upper limb and important indicators of growth and developmental age such as height (h), body mass (m b), skeletal age (SA), plasma testosterone (T) and pubertal stage (PS). We used the force-velocity (F-) relationship test in a population of 66 healthy adolescent male junior jockeys, with considerable variation in these indicators but of the same physical fitness level (training effect). The mean values of the maximal anaerobic power (W an,max) were 391 (SD 93) W. The values of the variables in the F- relationship for the upper limb were only slightly or uncorrelated with the chronological age, but highly correlated with h, m b and SA (P<0.001). The correlation with T was less significant. Using ANOVA a highly significant effect of PS on the variables in the F- relationship was found (P<0.001). The absolute or relative (normalized to m b) increase in W an,max during puberty was greater from PS P2 and P3 than at other stages. Therefore PS would appear to be a significant factor for developmental changes in anaerobic characteristics during puberty in the adolescent. The PS P3 determined only by public hair might be an easy and accurate indicator for sports category classification of adolescents during puberty  相似文献   

10.
W. N. Venables 《Biometrics》2010,66(2):656-657
An Introduction to Statistical Inference and Its Applications with R (M. W. Trosset) W. N. Venables ROC Curves for Continuous Data (W. J. Krzanowski and D. J. Hand) Lori E. Dodd A Guide to QTL Mapping with R/qtl (K. W. Broman and S. Sen) R. W. Doerge Design and Analysis of Clinical Trials with Time‐to‐Event Endpoint (K. E. Peace, ed.) Yu Shyr Translational Medicine: Strategies and Statistical Methods (D. Cosmatos and S.‐C. Chow) Yongzhao Shao Clinical Prediction Models: A Practical Approach to Development, Validation and Updating (E. W. Steyerberg) Rumana Omar Maximized Penalized Likelihood Estimation: Volume II: Regression (P. P. Eggermont and V. N. LaRicca) Hao Zhang Morphometrics with R (J. Claude) Alfred Kume Statistical Analysis of Network Data: Methods and Models (E. D. Kolaczyk) Crystal Linkletter  相似文献   

11.
Primula nghialoensis D. W. H. Rankin, a new species from Vietnam is described. It is assigned to the section Chartacea (Balf. f.) W.W.Sm., and its relationships with other members of this section, particularly P. petelotii, are discussed.  相似文献   

12.
The apple snail Pomacea canaliculata has been an invasive species in China for decades and causes enormous losses to agriculture. The predation capability of the leech Whitmania pigra on P. canaliculata was studied for its economic benefit and potential application. In the present study, the leech W. pigra exhibited a strong predatory capacity in controlling P. canaliculata under both laboratory and field conditions, and it showed no bias towards consuming smaller snails during the experiments. More than 80% of the 80 snails (of which half had reached maturity) were preyed upon by 20 developing leeches (2–7?g) in miniature rice fields over a 15-day period, and the number of rice seedlings damaged by P. canaliculata was decreased in the presence of W. pigra. In a separate experiment, 15 developing snails were exposed to caged leeches and conspecific snails for four weeks. The food intake and growth of P. canaliculata were inhibited under the predation risk imposed by W. pigra, but the feeding rate, food conversion efficiency and survival of P. canaliculata were not conspicuously influenced.  相似文献   

13.
The partial base sequences of 18S and 26S rRNAs of strains of Williopsis and Saturnospora species were analyzed. In the three regions partially sequenced, the higher base differences were observed in the strains examined of the three species, W. californica, W. mucosa, and W. pratensis, compared with those of W. saturnus var. saturnus (type species of genus Williopsis), W. beijerinckii, W. mrakii, W. saturnus var. subsufficiens, W. suaveolens, P. membranaefaciens (type species of genus Pichia), C. matritensis (type species of genus Citeromyces), and S’spora dispora (type species of genus Saturnospora): the percent similarities were 52–82 in positions 493–622, 130 bases, of 26S rRNA, and the number of base differences was 28–6 in positions 1611–1835, 225 bases, of 26S rRNA, and the number of base differences was 25–4 in positions 1451–1618, 168 bases, of 18S rRNA. In the 18S rRNA partial base sequencings, W. mucosa had an identical base sequence with P. anomala (≡ H. anomala, type species of genus Hansenula). Based on the sequence data obtained, the taxonomic positions of the three Williopsis species mentioned above are discussed. The genus Zygowilliopsis Kudriavzev was postulated to be retained and emended, and a new genus, Komagataea was proposed for W. pratensis with a new combination, Komagataea pratensis.  相似文献   

14.
Zhao  Lina  Wang  Yuanjian  Dhanasekaran  Solairaj  Guo  Zhipeng  Chen  Shangjian  Zhang  Xiaoyun  Zhang  Hongyin 《BioControl》2021,66(4):547-558

Blue mold decay is the one of most important postharvest disease of apples caused by the fungus, Penicillium expansum. This study aimed to investigate the biocontrol efficacy of the yeast, Wickerhamomyces anomalus, on postharvest blue mold decay of apples and the relative defense mechanisms. The results indicated that W. anomalus could significantly reduce the blue mold decay of apples, and the maximum inhibition was obtained when the concentration of W. anomalus was 1?×?108 cells ml?1. Furthermore, W. anomalus significantly reduced the fruit decay under ambient conditions, without generating any change in fruit quality. In vitro experiments showed that W. anomalus greatly inhibited the spore germination and germ tube elongation of P. expansum. Besides, its ease of adaptation, stable growth and potential colonization of in apple wounds or surfaces indicated that W. anomalus could compete with P. expansum for nutrients and space, leading to considerable inhibition blue mold decay. W. anomalus significantly induced the activities of polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT), phenylalanine ammonia-lyase (PAL), and ascorbate peroxidase (APX) in apples. Moreover, W. anomalus increased the contents of flavonoid and total phenols. All these results suggested that W. anomalus has potential biocontrol efficacy to control the postharvest blue mold decay of apples

  相似文献   

15.
For field application of a bacterial strain used to control Phythophthora capsici, we will need a biologically and economically efficient carrier medium. The known antagonist Paenibacillus ehimensisKWN38 was grown in a grass medium where it showed high antifungal and lytic enzyme activities. To demonstrate the potential of P. ehimensisKWN38 for biocontrol of late blight disease in pepper, pot trials were conducted by treating the 1‐month‐old plants with water (W), a selected grass medium (G3), G plus P. ehimensisKWN38 inoculation (G3P) or synthetic fungicide (F). The shoot dry weight in G3P was higher than that in W and F treatments at 15 days after zoospore infection (DZI). The root dry weight in G3P was also higher than that in W. The root mortality of G3 and W increased over 58 and 80% at 15 DZI, and some plants in those treatments wilted due to the failure of root physiology. The plants in G3P and F survived well because of their better root health conditions. Soil cellulase activity of G3P was consistently higher than that of W and F at earlier observation times (0, 2 and 6 DZI). The root β‐1,3‐glucanase activity of G3P promptly increased to maximum shortly after zoospore infection and reached the maximum value of 51.12 unit g?1 of fresh weight at 2 DZI. All these results indicate that inoculation of P. ehimensisKWN38 to the root zone of potted pepper plants increases plant growth, root and soil enzyme activities and alleviates the root death caused by infection with P. capsici zoospores.  相似文献   

16.
The yeast Wickerhamomyces anomalus has been studied for its wide biotechnological potential, mainly for applications in the food industry. Different strains of W. anomalus have been isolated from diverse habitats and recently from insects, including mosquitoes of medical importance. This paper reports the isolation and phylogenetic characterization of W. anomalus from laboratory‐reared adults and larvae of Phlebotomus perniciosus (Diptera: Psychodidae), a main phlebotomine vector of human and canine leishmaniasis. Of 65 yeast strains isolated from P. perniciosus, 15 strains were identified as W. anomalus; one of these was tested for the killer phenotype and demonstrated inhibitory activity against four yeast sensitive strains, as reported for mosquito‐isolated strains. The association between P. perniciosus and W. anomalus deserves further investigation in order to explore the possibility that this yeast may exert inhibitory/killing activity against Leishmania spp.  相似文献   

17.
《Journal of bryology》2013,35(3):309-319
Abstract

Sphagnum. inundatum Russow emend A. Eddy is lectotypified and combined with S. sub secundum Nees at the level of subspecies. S. auriculatum W.P. Schimper is a genetically distinct, but morphologically similar, species. S. subsecundum Nees subsp. subsecundum, S. subsecundum subsp. inundatum (Russ.) A. Eddy, stat. nov. and S. auriculatum W.P. Schimp. are described and figured and a key to their identification is given.  相似文献   

18.
To elucidate the effects of codon optimization and chaperone coexpression on the heterologous expression of mammalian cytochrome P450s (P450) in Escherichia coli, the expression of P450s 2B1, 2S1, 2U1, 2W1, and 27C1 were investigated. With codon optimization for N-terminus or the entire gene, the expression levels of P450 27C1, 2U1 and 2W1 increased 22-fold, 3.6-fold and 2.1-fold, respectively, while those for P450s 2B1 and 2S1 remained unchanged. With coexpression of E. coli molecular chaperones GroEL/ES, the expression level increased up to 14-fold for P450 27C1, and 3- to 5-fold for P450s 2B1, 2S1, and 2W1. Simultaneous application of these two techniques resulted in synergetic effects.  相似文献   

19.
The antifungal activities of 85 lactic acid bacteria strains isolated from fermented wax gourd against the four fungal species, Penicillium oxalicum, Aspergillus flavus, Aspergillus sydowii, and Mucor racemosus, were determined. Inhibitory activity against at least one or more fungal species was observed with 27 Weissella cibaria and 11 Weissella paramesenteroides strains. Among these strains, W. cibaria 861006 and W. paramesenteroides 860509 showed greater inhibitory activities and were therefore selected for further analysis. The results suggested that the antifungal activities were originated from the organic acids produced by W. cibaria 861006 and W. paramesenteroides 860509. The application tests indicated that the growth of P. oxalicum could be effectively inhibited by W. cibaria 861006 for 6 days on grape surfaces. However, W. paramesenteroides 860509 could only remain its inhibition effect for 48 h. The findings obtained in this study suggest the potential use of W. cibaria 861006 as a bio-protective agent against fungi for agricultural purposes or ready-to-eat fresh fruit and vegetable products.  相似文献   

20.
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