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151.
The combined effect of Vesicular Arbuscular Mycorrhizae (VAM) and Rhizobium on the cold season legumes, lentil and faba bean,
as well as on summer legume, soybean, were studied in soils with low indeginous VA mycorrhizal spores. Inoculation of the
plant with VA mycorrhizal fungi increased the level of mycorrhizal root infection of lentil, faba bean and soybean. The inoculation
with Rhizobium had no significant effect on VA mycorrhizal infection percent, but VA mycorrhizal inoculation increased nodulation
of the three legumes.
The inoculation with Rhizobium alone significantly increased plant dry weight and N content of lentil and faba bean as well
as seed yield of soybean. VA mycorrhizal inoculation also significantly increased plant dry weight and phosphorus content
of the plants as did fertilization with superphosphate. Rock phosphate fertilization, however, had no significant effect on
plant growth or phosphorus uptake. The addition of rock phosphate in combination with VA mycorrhizal inoculation significantly
increased plant dry weight and P uptake of the plants.
The dual inoculation with both rhizobia and mycorrhizae induced more significant increases in plant dry weight, N and P content
of lentil and faba bean as well as seed yield of soybean than inoculation with either VA mycorrhizae or Rhizobium alone. 相似文献
152.
A nearly universal feature of intron sequences is that even closely related
species exhibit a large number of insertion/deletion differences. The goal
of the analysis described here is to test whether the observed pattern of
insertion/deletion events in the genealogy of the myosin alkali light chain
(Mlc1) gene is consistent with neutrality, and if not, to determine the
underlying forces of evolutionary change. Mlc1 pre-mRNA is alternatively
spliced, and one constraint is that signals necessary for
tissue-specificity of directed splicing must be conserved. If the total
length of an intron is functionally constrained, then the distribution of
indels on branches of the gene genealogy should reflect a departure from
randomness. Here we perform a phylogenetic analysis, inferring ancestral
states wherever possible on a phylogeny of 29 alleles of Mlc1 from six
species of Drosophila. Observed patterns of indels on the genealogy were
compared to those from simulated data, with the result that we cannot
reject the null hypothesis of neutrality. A clear departure from a neutral
prediction was seen in the excess folding free energy predicted for the
introns flanking the alternatively spliced exon. Relative rate tests also
suggest a retardation in the rate of Mlc1 sequence evolution in the
simulans clade.
相似文献
153.
Nouran Abd-ElMoemen Ahmed Menshawy Ahmed Negida Marwa Alaa El-Din Ahmed Kamel Alaa Ehab Farouk 《International journal of peptide research and therapeutics》2016,22(1):135-141
One of the current international public health emergencies is the outbreak of Ebola virus disease (EVD), requiring extraordinary response. The current outbreak in West Africa is the most dangerous since Ebola was first discovered on 26 August 1976. Till January 6th 2015, It resulted in 13,387 laboratory confirmed human cases and 8274 deaths. Ebola virus has 5 strains, 4 are pathogenic in humans while the 5th strain Ebola reston strain is not. The current outbreak is caused by Ebola most pathogenic strain, Ebola Zaire strain whose genome differs from that of Reston Ebola virus strain, by the existence of several open reading frames containing large numbers of UGA codons. These codons act as stop codons and in addition they may encode for Selenocysteine, the 21st aminoacid, which is essential for the formation of Selenoproteins. Selenoproteins are integral to the metabolism and have been linked to the progression of certain viral diseases. In this review, we discuss the relation between Selenium and the progression of the current EVD in Africa supported by geographical distribution of Se and genetic evidence. 相似文献
154.
El-Din El-Assal S Alonso-Blanco C Peeters AJ Wagemaker C Weller JL Koornneef M 《Plant physiology》2003,133(4):1504-1516
We have investigated the genetic interactions between cry2 and the various flowering pathways in relation to the regulation of flowering by photoperiod and vernalization. For this, we combined three alleles of CRY2, the wild-type CRY2-Landsberg erecta (Ler), a cry2 loss-of-function null allele, and the gain-of-function CRY2-Cape Verde Islands (Cvi), with mutants representing the various photoreceptors and flowering pathways. The analysis of CRY2 alleles combined with photoreceptor mutants showed that CRY2-Cvi could compensate the loss of phyA and cry1, also indicating that cry2 does not require functional phyA or cry1. The analysis of mutants of the photoperiod pathway showed epistasis of co and gi to the CRY2 alleles, indicating that cry2 needs the product of CO and GI genes to promote flowering. All double mutants of this pathway showed a photoperiod response very much reduced compared with Ler. In contrast, mutations in the autonomous pathway genes were additive to the CRY2 alleles, partially overcoming the effects of CRY2-Cvi and restoring day length responsiveness. The three CRY2 alleles were day length sensitive when combined with FRI-Sf2 and/or FLC-Sf2 genes, which could be reverted when the delay of flowering caused by FRI-Sf2 and FLC-Sf2 alleles was removed by vernalization. In addition, we looked at the expression of FLC and CRY2 genes and showed that CRY2 is negatively regulated by FLC. These results indicate an interaction between the photoperiod and the FLC-dependent pathways upstream to the common downstream targets of both pathways, SOC1 and FT. 相似文献
155.
Adelmo L Cechin Marialva Sinigaglia Ney Lemke Sérgio Echeverrigaray Odalys G Cabrera Gonçalo AG Pereira José CM Mombach 《BMC plant biology》2008,8(1):50
Background
NEP1-like proteins (NLPs) are a novel family of microbial elicitors of plant necrosis. Some NLPs induce a hypersensitive-like response in dicot plants though the basis for this response remains unclear. In addition, the spatial structure and the role of these highly conserved proteins are not known. 相似文献156.
157.
SDS — dissociated proteins from eight isolates belonging to threeFusarium species were assessed and compared using polyacrylamide gel electrophoresis. Intra and inter specific variation in banding patterns were analyzed both qualitatively and quantitatively. Special emphasis was placed on variability of protein banding pattern between two nonpathogenic strains ofF. oxysporum (C5 and C14). Protein profiles from host-associated isolates were distinct, and each isolate showed a uniquely characteristic profile. Attempts were made to provide information on the genetic system controlling pathogenicity, compared to nonpathogenicity, at the protein level. The data obtained from electrophoresis support the potential use of this experimental approach to help distinguish between differentFusarium isolates. 相似文献
158.
Biochemical Decomposition of the Herbicide N-(3,4-Dichlorophenyl)-2-Methylpentanamide and Related Compounds 总被引:4,自引:4,他引:0 下载免费PDF全文
Organisms capable of decomposing N-(3,4-dichlorophenyl)-2-methylpentanamide (Karsil) were isolated, identified, and tested for their ability to hydrolyze this herbicide. Primary products of Karsil decomposition by cells and cell-free extracts of a Penicillium sp. were identified as 2-methyl-valeric acid and 3,4-dichloroaniline. The Karsil acylamidase (EC 3.5.1.a aryl acylamine amidohydrolase) was an induced enzyme. It was partially purified and tested for its ability to hydrolyze 25 related compounds. Some relations between the structures of these compounds and their susceptibility to enzymatic hydrolysis were discerned. 相似文献
159.
Industrial biotechnology employs the controlled use of microorganisms for the production of synthetic chemicals or simple
biomass that can further be used in a diverse array of applications that span the pharmaceutical, chemical and nutraceutical
industries. Recent advances in metagenomics and in the incorporation of entire biosynthetic pathways into Saccharomyces cerevisiae have greatly expanded both the fitness and the repertoire of biochemicals that can be synthesized from this popular microorganism.
Further, the availability of the S. cerevisiae entire genome sequence allows the application of systems biology approaches for improving its enormous biosynthetic potential.
In this review, we will describe some of the efforts on using S. cerevisiae as a cell factory for the biosynthesis of high-value natural products that belong to the families of isoprenoids, flavonoids
and long chain polyunsaturated fatty acids. As natural products are increasingly becoming the center of attention of the pharmaceutical
and nutraceutical industries, the use of S. cerevisiae for their production is only expected to expand in the future, further allowing the biosynthesis of novel molecular structures
with unique properties. 相似文献
160.