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1.
Ming Pei You Brandon Lancaster Krishnapillai Sivasithamparam Martin John Barbetti 《Plant and Soil》2008,302(1-2):203-211
In Australia, in the past, pasture legumes were rotated mainly with cereals, but increasingly these rotations now involve
pasture legumes with a wider range of crops, including legumes. This increasing frequency of the leguminous host in the rotation
system may be associated with increased root rots in legumes in the current pasture-crop rotations. The primary aim of this
study was to see whether the pathogenicity on pasture legumes of strains of Rhizoctonia solani sourced from lupins and cereals (common crops in rotation with pastures) is associated with increased incidence of root rots
in pasture legumes in the disease conducive sandy soils of the Mediterranean regions of southern Australia. The second aim
was to determine sources of resistance among newly introduced pasture legumes to R. solani strains originating from rotational crops as this would reduce the impact of disease in the pasture phase. Fifteen pasture
legume genotypes were assessed for their resistance/susceptibility to five different zymogram groups (ZG) of the root rot
pathogen R. solani under glasshouse conditions. Of the R. solani groups tested, ZG1–5 and ZG1–4 (both known to be pathogenic on cereals and legumes) overall, caused the most severe root
disease across the genotypes tested, significantly more than ZG6 (known to be pathogenic on legumes), in turn significantly
>ZG4 (known to be pathogenic on legumes) which in turn was >ZG11 (known to be pathogenic on legumes including tropical species).
Overall, Ornithopus sativus Brot. cvs Cadiz and Margurita, Trifolium michelianum Savi. cvs Paradana and Frontier and T. purpureum Loisel. cv. Electro showed a significant level of resistance to root rot caused by R. solani ZG11 (root disease scores ≤1.2 on a 1–3 scale where 3 = maximum disease severity) while O. sativus cvs Cadiz and Erica showed a significant level of resistance to root rot caused by R. solani ZG4 (scores ≤1.2). O. compressus L. cvs Charano and Frontier, O. sativus cv. Erica, and T. purpureum cv. Electro showed some useful resistance to root rot caused by R. solani ZG6 (scores ≤1.8). This is the first time that cvs Cadiz, Electro, Frontier, Margurita and Paradana have been recognised
for their levels of resistance to root rot caused by R. solani ZG11; and similarly for cvs Cadiz and Erica against ZG4; and for cvs Charano, Erica, and Electro against ZG6. These genotypes
with resistance may also serve as useful sources of resistance in pasture legume breeding programs and also could potentially
be exploited directly into areas where other rotation crops are affected by these R. solani strains. None of the tested genotypes showed useful resistance to R. solani ZG1–4 (scores ≥2.0) or ZG1–5 (scores ≥2.5). This study demonstrates the relative potential of the various R. solani ZG strains, and particularly ZG1–4, ZG1–5, ZG4 and ZG6 to attack legume pastures and pose a significant threat to non-pasture
crop species susceptible to these strains grown in rotation with these pasture legumes. Significantly, the cross-pathogenicity
of these strains could result in the continuous build-up of inoculum of these strains that may seriously affect the productivity
eventually of legumes in all rotations. In particular, when choosing pasture legumes as rotation crops, caution needs to be
exercised so that the cultivars deployed are those with the best resistance to the R. solani ZGs most likely to be prevalent at the location. 相似文献
2.
3.
A determinant of polyomavirus virulence enhances virus growth in cells of renal origin. 总被引:3,自引:2,他引:1 下载免费PDF全文
J B Bolen S E Fisher K Chowdhury T C Shan J E Williams C J Dawe M A Israel 《Journal of virology》1985,53(1):335-339
We have identified a strain of polyomavirus, Py(L), which is unusual in causing acute morbidity and early death after inoculation of newborn mice. We determined that these animals died of kidney failure associated with extensive, virus-mediated destruction of renal tissue. Interestingly, the Py(L) strain infects baby mouse kidney cell cultures more efficiently than do other strains. 相似文献
4.
Stereospecificity for nicotinamide nucleotides in enzymatic and chemical hydride transfer reactions 总被引:3,自引:0,他引:3
K S You 《CRC critical reviews in biochemistry》1985,17(4):313-451
The pyridine nucleotide (NAD and NADP)-linked enzymes are a large class of enzymes constituting approximately 17% of all classified enzymes. When these enzymes catalyze their reactions, the hydride transfer between the substrate and the reaction site (i.e., C-4 of the nicotinamide/dihydronicotinamide ring) of the coenzyme takes place in a stereospecific manner. Thus, in the reaction of oxidation of the reduced coenzyme, one group of enzymes catalyzes the extraction of only the hydrogen having the R configuration at the No. 4 carbon, while the other group catalyzes the removal of only that with the S configuration. Because this aspect of enzyme stereospecificity provides essential information for a given enzyme's reaction mechanism, active site structure, and evolutionary relationship with other enzymes, intensive effort has been made to establish the stereospecificities of as many enzymes as possible. This review presents the compilation of the stereospecificities of these enzymes. Some empirical rules, which are useful but not definitive, in predicting a given enzyme's stereospecificity are also described. In addition, the stereospecificity in enzymatic reactions is compared to the stereo-preference in chemical oxidoreduction of the coenzyme. In order to elucidate the mechanism for the enzyme stereospecificity, the conformations of the coenzyme in free-state and enzyme-bound state are extensively discussed here. 相似文献
5.
6.
兴安落叶松结实规律与长短枝习性的关系 总被引:1,自引:0,他引:1
1987年5月,大兴安岭林区发生的特大森林火灾,实属世界罕见,火灾面积达1.0×10~6ha 多。大量的火烧迹地亟待更新、无论是人工更新还是人工促进天然更新,其中关键的问题之一是种子的来源,在大兴安岭地区,兴 相似文献
7.
8.
Yeast Mutants That Produce a Novel Type of Ascus Containing Asci Instead of Spores 总被引:2,自引:0,他引:2 下载免费PDF全文
Tetraploid yeast cells lacking BFR1 or overexpressing an essential gene BBP1 produce a novel type of ascus that contains asci instead of spores. We show here that the asci within an ascus likely arise because a/α spores undergo a second round of meiosis. Cells depleted of Bbp1p or lacking Bfr1p are defective in a number of processes such as nuclear segregation, bud formation, cytokinesis and nuclear spindle formation. Furthermore, deletion of BFR1 or overexpression of BBP1 leads to an increase in cell ploidy, indicating that Bfr1p and Bbp1p play roles in both the mitotic cell cycle and meiosis. Bfr1p and Bbp1p interact with each other in a two hybrid assay, further suggesting that they might form a complex important for cell cycle coordination. 相似文献
9.
汉防己甲素(汉甲)及克矽平(Polyvinylpyridine-N-Oxide,PVNO)是目前较为有效的抑制矽肺纤维化的药物。本文研究了其对胶原mRNA水平的影响.斑点杂交实验表明大鼠接尘60天和120天后α1(Ⅰ)及α1(Ⅲ)mRNA水平明显上升,经汉甲或克矽平治疗1个月或3个月后,胶原mRNA水平明显下降。原位杂交结果表明胶原mR-NA银颗粒与细胞性结节和增厚的肺泡壁的成纤维细胞分布重合。汉甲或克矽平治疗后银颗粒数下降。提示汉甲及克矽平对矽肺进程中的胶原基因表达增强有抑制作用。 相似文献
10.
Niraj Shrestha Pallavi Chaturvedi Xiaoyun Zhu Michael J. Dee Varghese George Christopher Janney Jack O. Egan Bai Liu Mark Foster Lynne Marsala Pamela Wong Celia C. Cubitt Jennifer A. Foltz Jennifer Tran Timothy Schappe Karin Hsiao Gilles M. Leclerc Lijing You Christian Echeverri Catherine Spanoudis Ana Carvalho Leah Kanakaraj Crystal Gilkes Nicole Encalada Lin Kong Meng Wang Byron Fang Zheng Wang Jin-an Jiao Gabriela J. Muniz Emily K. Jeng Nicole Valdivieso Liying Li Richard Deth Melissa M. Berrien-Elliott Todd A. Fehniger Peter R. Rhode Hing C. Wong 《Aging cell》2023,22(5):e13806