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Palynological Study of the Genus Crepis from Pakistan  [PDF]
Sohail Jamil Qureshi,Abdul Ghani Awan,Mir Ajab Khan,Sofia Bano
Asian Journal of Plant Sciences , 2002,
Abstract: Pollen morphology of four different species, Crepis flexuosa, Crepis multicaulis, Crepis sancta and Crepis thomsonii, belonging to genus Crepis of family Asteraceae were studied from Pakistan. Morphology of pollen grains of each of the species is based on 20 specimens selected at random. Proposed characters i.e., grain, shape of pollen grain, equatorial view, polar view, equatorial diameter (E), polar diameter (P), P / E ratio, length of colpus, exine surface, exine thickness, inter poral distance, inter spinal distance, inter spinal outline, length of spines and number of spines between colpi in each species were recorded for comparison. At species level, micromorphological differences and distribution of surface pattern, shape and size of pollen have been found to exist. The pollen grains are consistently echinate and trizonocolporate. Maximum equatorial diameter, polar diameter and colpus length was observed in Crepis multicaulis while in Crepis flexuosa spine length and exine thickness is found top be maximum. Inter poral distance is minimum in Crepis flexuosa. Inter spinal distance & P/E ratio is higher in Crepis thomsonii. This study demonstrates the potential of pollen studies in distinguishing some taxonomic groups in the Asteraceae.
Sesquiterpene lactones from Crepis setosa Hal.
Wanda Kisiel,Stanis?aw Kohlmünzer
Acta Societatis Botanicorum Poloniae , 1990, DOI: 10.5586/asbp.1990.008
Abstract: The roots of Crepis setosa Hall. afforded four sesquiterpene lactones, among them three glycosides, all derived from 11β,13-dihydrozaluzanin C and not previously reported from this species.
Factors affecting the development of Septoria leaf spotof tomato  [cached]
Indian Phytopathology , 2012,
Abstract: The roles of inoculum load, host extracts, leachates, dew and leaf wetness were determined on the development of Septoria leaf spot (Septoria lycopersici) of tomato in Himachal Pradesh, India. An increase in inoculum accelerated the progress of disease development. An inoculum load of 525-1050 spores/ml and leaf wetness in the range of 48-60 h were optimum for the normal development of disease under artificial inoculation tests. Inoculum in extract and leachate of various host parts and dew accelerated development of the disease. Leaf extract and leachate were stimulatory and extracts of unripe fruits were inhibitory to disease development.
Influence of the Presence of B Chromosomes on DNA Damage in Crepis capillaris  [PDF]
Jolanta Kwasniewska, Agnieszka Mikolajczyk
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0087337
Abstract: The sensitivity of different plant species to mutagenic agents is related to the DNA content and organization of the chromatin, which have been described in ABCW and bodyguard hypotheses, respectively. Plant species that have B chromosomes are good models for the study of these hypotheses. This study presents an analysis of the correlation between the occurrence of B chromosomes and the DNA damage that is induced by the chemical mutagen, maleic hydrazide (MH), in Crepis capillaris plants using comet assay. The presence of B chromosomes has a detectable impact on the level of DNA damage. The level of DNA damage after MH treatment was correlated with the number of B chromosomes and it was observed that it increased significantly in plants with 3B chromosomes. We did not find evidence of the protective role from chemical mutagens of the constitutive heterochromatin for euchromatin in relation to DNA damage. The DNA damage involving the 25S rDNA sequences was analyzed using the comet-FISH technique. Fragmentation within or near the 25S rDNA involved the loci on the A and B chromosomes. The presence of B chromosomes in C. capillaris cells had an influence on the level of DNA damage that involves the 25S rDNA region.
Septoria的新种和国内新记录种  [PDF]
菌物学报 , 1993,
Abstract: 作者在1987-1991年间从东北地区收集和采集Septoria真菌标本221份,鉴定出Septoria84种,其中2个新种:SeptoriadioscoricalLuGuo-zhongetBaiJin-kai和SeptoriasaposhinikoviaeLuGuo-zhongetBaiJin-kai,以及13个国内新记录种.Septoria属真菌的产孢方式为全壁芽生合轴式(holoblasticsympodial)。
Crepis capillaris Wallr. (Compositae, Lactuceae), una adición a la flora adventicia de México
Jerzy Rzedowski,Graciela Calderón De Rzedowski
Acta botánica mexicana , 2005,
Abstract: Se registra por primera vez para México la presencia de Crepis capillaris, maleza originaria de Europa. Se le observó como ruderal e invadiendo agostaderos en la parte central del estado de Veracruz, entre 1900 y 2450 m de altitud, en condiciones de clima húmedo. Se estima que su arribo a esta área debe datar de hace no mucho más de 20 a os.
Aggressiveness and physiological specialization of Septoria tritici Rob. isolates
Gieco, Jorge Omar;Dubcovsky, Jorge;Camargo, Luis Eduardo Aranha;
Scientia Agricola , 2004, DOI: 10.1590/S0103-90162004000400010
Abstract: pathogenicity tests verifying the behavior of septoria tritici isolates should be considered as a priority in the selection of resistant wheat materials to this pathogen, since the aggressiveness of each isolate can vary significantly, causing problems in the evaluation and selection of resistant genotypes. the objective of this work was to determine whether physiologic specialization exists among argentinean and american septoria tritici isolates, through the analysis of their pathogenicity on cultivars and lines of bread wheat (triticum aestivum l.). the experiments were carried out in castelar-argentina and in davis-usa. in castelar, a split plot design (n = 4) was used. the cultivars or lines were randomized in the plots and the isolates in the subplots. each subplot consisted of three plants belonging to a cultivar or line. in davis, a strip split plot design (n = 6) was used. a pot containing three plants of each cultivar or line constituted the experimental plots. in both sites, the inoculation was made at the flag leaf phenological stage through foliar aspersion of a conidial suspension adjusted to 106-108 conidia ml-1. evaluations were made by recording the leaf area covered with pycnidia (lacp) at the flag leaf stage with the use of rating scales. differences (p < 0.0001) in lacp were detected among cultivars or lines. isolate effects and the interaction cultivar × isolate were significant (p < 0.0001). variations in aggressiveness and virulence were found among the isolates, indicating the presence of horizontal and vertical resistance in the host cultivars.
The Screening Research of Anti-Inflammatory Bioactive Markers from Different Flowering Phases of Flos Lonicerae Japonicae  [PDF]
Min Jiang, Yan-qi Han, Meng-ge Zhou, Hong-zhi Zhao, Xue Xiao, Yuan-yuan Hou, Jie Gao, Gang Bai, Guo-an Luo
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0096214
Abstract: Flos Lonicerae Japonicae (FLJ) is an important cash crop in eastern Asia, and it is an anti-inflammatory Traditional Chinese Medicine. There are large variations in the quality of the marketed FLJ products. To find marker ingredients useful for quality control, a tandem technology integrating ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-Q/TOF), principal component analysis (PCA), heat map analysis and hierarchical cluster analysis coupled with a NF-κB luciferase reporter gene assay were used to identify the different ingredients from the green bud, white bud, flowering stage and leaf stages, as well as to screen the anti-inflammatory activity of FLJ compositions. As flowering progressed, the anti-inflammatory effects of FLJ gradually decreased; however, chlorogenic acid, swertiamarin and sweroside should be used to evaluate the quality of FLJ products.
Reduction of incidence and severity of Septoria lycopersici leaf spot of tomato with bacteria and yeasts
Blum, Luiz Eduardo Bassay;
Ciência Rural , 2000, DOI: 10.1590/S0103-84782000000500003
Abstract: septoria leaf spot, caused by septoria lycopersici, is an important disease of tomato (lycopersicon esculentum) which is mainly controlled by fungicide sprays. one of the alternatives to reduce fungicide applications is the use of leaf antagonists such as yeast and bacterium. this study was conducted from 1994 through 1995 in auburn, al, usa. the pathogen and one antagonist were isolated from field plants. in greenhouse, six yeast and one bacterial isolates were tested, in a set of seven experiments. the experiments were conducted in a completely randomized design with four to eight treatments and six replications. the antagonists (1-3 ′ 108 colony forming units ml-1) were inoculated 48h before the inoculation of the pathogen (1-2 ′ 105 conidia ml-1), under conditions of intermittent misting. the yeast isolate y236 (cryptococcus laurentii) and the bacterial isolate btl (pseudomonas putida) significantly (p £ 0.05) reduced the incidence or the severity of the disease in most experiments.
抗Septoria颖(叶)枯病的小麦样本  [PDF]
麦类作物学报 , 1991, DOI: 10.7606/j.issn.1009-1041.1991.04.074
Abstract: 近几年来,早已危害不大的一些真菌病危害程度又在急剧增大.小麦颖枯病(LeptosphaerianodorumMuller)或小麦叶枯病(Mycosphaerellagraminicola〔Fuckel〕Schroeter)就属于这类病害.众所周知,对这些病原体的抗性是多基因控制的数量性状(BronnimanuA.,1982;MullaneyE.J.等,1982).在小麦胚的原生质中含有完全符合免疫育种所需的抗Septoria颖(叶)枯病的因子.但这种抗性常与高秆、晚熟等不良经济性状相关(ShiptonW.A.等,1971;ScottP.R.等,1982).抗Septoria颖(叶)桔病病原体
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