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101.
102.
Tian Guo 《Biocontrol Science and Technology》2014,24(1):116-121
We have identified a promising antagonistic micro-organism for suppressing Rhizoctonia solani and triggering induced resistance in rice. The isolate PS04 was identified as Paenibacillus kribbensis. PS04 and its crude metabolites showed inhibitory effects against R. solani both in vitro and in vivo, and with high stability against temperature and pH. Strain PS04 is a great biocontrol agent. 相似文献
103.
R Samiyappan G Amutha A Kandan R Nandakumar S Babu A Vijayasamundeeswari 《Archives Of Phytopathology And Plant Protection》2013,46(3-4):247-256
An extracellular, hydrophilic, thermostable phytotoxin was purified to homogeneity from culture fluids of Sarocladium oryzae and sheath rot infected rice plants. The phytotoxin was purified by solvent extraction, gel filtration on Sephadex G-75 and HPLC. Toxicity was evaluated with detached leaf sheath and electrolyte leakage bioassays. Purified phytotoxin induced visible symptoms of the disease, when applied to rice sheath even at a low concentration of 5?μg. The toxin is a glycoprotein with carbohydrate as major component. The importances of the carbohydrate moiety for toxic activity was indicated by inactivation of toxic compound after periodate oxidation. The toxin caused lesions on a number of other monocots and dicots and proved to be non-host specific. This is the first report of the purification and characterization of S. oryzae toxin from in vitro and in vivo and we propose its name SO-toxin. 相似文献
104.
Transition protein 2 is a basic chromosomal protein which functions as an intermediate in the replacement of histones by protamines, and the mitochondrial capsule seleno-protein is a constituent of the outer membrane of mitochondria which functions in constructing the mitochondrial sheath surrounding the flagellum. To determine precisely the stages in spermatogenesis when these mRNAs are present, paraffin sections of sexually mature testes were hybridized to 35S- and 3H-labeled antisense RNAs and exposed to autoradiographic emulsion. The cell types hybridizing to probes in situ were determined by staining with hematoxylin and periodic acid Schiff. The in situ hybridizations reveal that the transition protein 2 mRNA is first detectable in step 7 round spermatids, persists at high levels through step 13, and is degraded before step 14. By contrast, the mitochondrial capsule seleno-protein mRNA is first detected in step 3 round spermatids and persists at high levels until step 16, the end of spermiogenesis. The mitochondrial capsule seleno-protein mRNA appears to be expressed only in haploid cells since low levels could not be detected in Northern blots of RNA from pachytene primary spermatocytes from 18 day prepubertal mice. These results demonstrate that the transition protein 2 and mitochondrial capsule seleno-protein mRNAs are transcribed and degraded at different times during the haploid phase of spermatogenesis. 相似文献
105.
Anatomy of non-uniform leaf photosynthesis 总被引:24,自引:0,他引:24
Ichiro Terashima 《Photosynthesis research》1992,31(3):195-212
Since 1986, non-uniform photosynthesis over the leaf area that may be attributed to patchy stomatal closure, has been an important issue in stress physiology of photosynthesis. In this review, I first outline the gaseous environment within the intercellular spaces, because this is the most fundamental background of this problem. Then, recent studies approaching non-uniform photosynthesis are reviwed. After examining techniques for the detection of non-uniform photosynthesis or non-uniform stomatal aperture, results of the relevant studies are discussed for respective stress factors, seeking causes and consequences of non-uniform photosynthesis. From these, mechanisms responsible for, and consequences of non-uniform photosynthesis, are considered. The problems which should be challenged are also pointed out.Abbreviations A
rate of photosynthetic CO2 fixation (assimilation rate)
- ABA
abscisic acid
- g
conductance for CO2 or H2O
- pa
partial pressure of CO2 in the ambient air
- pi
partial pressure of CO2 in the intercellular space
- pi
pi estimated by the conventional gas exchange techniques
- qN
non-photochemical quenching
- qp
photochemical quenching 相似文献
106.
107.
Felipe Berti Valer Maiaro Cabral Rosa Machado Rui Milton Patrício Silva‐Junior Ricardo Guelerman Pinheiro Ramos 《Genesis (New York, N.Y. : 2000)》2018,56(9)
The Irre cell‐recognition module (IRM) is a group of evolutionarily conserved and structurally related transmembrane glycoproteins of the immunoglobulin superfamily. In Drosophila melanogaster, it comprises the products of the genes roughest (rst; also known as irreC‐rst), kin‐of‐irre (kirre; also known as duf), sticks‐and‐stones (sns), and hibris (hbs). In this model organism, the behavior of this group of proteins as a partly redundant functional unit mediating selective cell recognition was demonstrated in a variety of developmental contexts, but their possible involvement in ovarian development and oogenesis has not been investigated, notwithstanding the fact that some rst mutant alleles are also female sterile. Here, we show that IRM genes are dynamically and, to some extent, coordinately transcribed in both pupal and adult ovaries. Additionally, the spatial distribution of Hbs, Kirre, and Rst proteins indicates that they perform cooperative, although largely nonredundant, functions. Finally, phenotypical characterization of three different female sterile rst alleles uncovered two temporally separated and functionally distinct requirements for this locus in ovarian development: one in pupa, essential for the organization of peritoneal and epithelial sheaths that maintain the structural integrity of the adult organ and another, in mature ovarioles, needed for the progression of oogenesis beyond stage 10. 相似文献
108.
Rhizosphere‐associated Alcaligenes and Bacillus strains that induce resistance against blast and sheath blight diseases,enhance plant growth and improve mineral content in rice 下载免费PDF全文
K.U. Kakar Z. Nawaz Z. Cui A.A. Almoneafy R. Ullah Q.‐Y. Shu 《Journal of applied microbiology》2018,124(3):779-796
109.
Versatile Core–Sheath Yarn for Sustainable Biomechanical Energy Harvesting and Real‐Time Human‐Interactive Sensing 下载免费PDF全文
Kai Dong Jianan Deng Wenbo Ding Aurelia C. Wang Peihong Wang Chaoyu Cheng Yi‐Cheng Wang Limin Jin Bohong Gu Baozhong Sun Zhong Lin Wang 《Liver Transplantation》2018,8(23)
The emergence of stretchable textile‐based mechanical energy harvester and self‐powered active sensor brings a new life for wearable functional electronics. However, single energy conversion mode and weak sensing capabilities have largely hindered their development. Here, in virtue of silver‐coated nylon yarn and silicone rubber elastomer, a highly stretchable yarn‐based triboelectric nanogenerator (TENG) with coaxial core–sheath and built‐in spring‐like spiral winding structures is designed for biomechanical energy harvesting and real‐time human‐interactive sensing. Based on the two advanced structural designs, the yarn‐based TENG can effectively harvest or respond rapidly to omnifarious external mechanical stimuli, such as compressing, stretching, bending, and twisting. With these excellent performances, the yarn‐based TENG can be used in a self‐counting skipping rope, a self‐powered gesture‐recognizing glove, and a real‐time golf scoring system. Furthermore, the yarn‐based TENG can also be woven into a large‐area energy‐harvesting fabric, which is capable of lighting up light emitting diodes (LEDs), charging a commercial capacitor, powering a smart watch, and integrating the four operational modes of TENGs together. This work provides a new direction for textile‐based multimode mechanical energy harvesters and highly sensitive self‐powered motion sensors with potential applications in sustainable power supplies, self‐powered wearable electronics, personalized motion/health monitoring, and real‐time human‐machine interactions. 相似文献
110.
Sergey Nazarov Johannes P Schneider Maximilian Brackmann Kenneth N Goldie Henning Stahlberg Marek Basler 《The EMBO journal》2018,37(4)
The bacterial Type VI secretion system (T6SS) assembles from three major parts: a membrane complex that spans inner and outer membranes, a baseplate, and a sheath–tube polymer. The baseplate assembles around a tip complex with associated effectors and connects to the membrane complex by TssK. The baseplate assembly initiates sheath–tube polymerization, which in some organisms requires TssA. Here, we analyzed both ends of isolated non‐contractile Vibrio cholerae sheaths by cryo‐electron microscopy. Our analysis suggests that the baseplate, solved to an average 8.0 Å resolution, is composed of six subunits of TssE/F2/G and the baseplate periphery is decorated by six TssK trimers. The VgrG/PAAR tip complex in the center of the baseplate is surrounded by a cavity, which may accommodate up to ~450 kDa of effector proteins. The distal end of the sheath, resolved to an average 7.5 Å resolution, shows sixfold symmetry; however, its protein composition is unclear. Our structures provide an important step toward an atomic model of the complete T6SS assembly. 相似文献