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2.
Summary
Azolla accessions (section Azolla) from the germplasm collections of the International Rice Research Institute and Washington State University were fingerprinted and classified by enzyme electrophoresis and leaf trichome morphology. A. filiculoides was enzymatically distinctive and also reliably identified by its prominent one-celled trichomes. Neotropical accessions labelled as A. filiculoides proved to be members of other species. Two groups of isolates were designated A. rubra, but those from Japan were identified as A. filiculoides. The A. rubra of Australia-New Zealand was biochemically unique and possessed less protuberant trichomes than A. filiculoides. A. microphylla, A. mexicana, and A. caroliniana were phenetically similar, but a. microphylla was identifiable from the others in the banding patterns of certain enzymes. A. mexicana and A. caroliniana were closely related enzymatically. The two-celled leaf trichomes of these three species were similar in size and shape. 相似文献
3.
果实褐腐病的调查与防治研究 总被引:7,自引:0,他引:7
通过系统考察,标本采集,分离培养、鉴定,电镜扫描及酯酶同工酶电泳分析,明确我国丛梗孢属Monilia的种类及其寄主与分布,通过室内毒力测定,筛选出有效化学药剂并对桃褐腐病进行两年的综合防治,防效明显. 相似文献
4.
本实验用聚丙烯酸胺凝胶电泳(PAGE)方法,对塔里木河大狗头鱼(学名:叶尔羌鼓鳔鳅)六种不同组织(骨骼肌、心、肝胰、肾、肠、鳃)中LDH同工酶进行了分析研究,结果表明,LDH同工酶具有组织特异性,其中骨骼肌中含有五种LDH同工酶,即LDH1、LDH2、LDH3、LDH4、LDH5,心、肝胰和肾含有LDH1、LDH2、LDH3,鳃有LDH1和LDH4,肠有LDH4。 相似文献
5.
[目的]为探究克氏原螯虾的食用安全性以及哈夫病的致病因素等提供检测方法。[方法]以孝感市不同水域中生活的克氏原螯虾为材料,对其主要组织的LDH同工酶进行电泳分析。[结果]2处水域的pH、总磷、总氮和化学需氧量存在差异,2处水域中克氏原螯虾的鳃、心脏和肌肉的LDH同工酶酶谱也存在差异。B水域(流水)中克氏原螯虾的酶带数目比A水域(静水)多。从Ldh-5同工酶染色深浅可以看出,静水虾肝胰腺、心脏和眼球的Ldh-5同工酶活力比流水虾的大,而肌肉和腮则是流水虾的Ldh-5同工酶活力较大。[结论]2处水域克氏原螯虾组织LDH同工酶的差异是由水质差异引起的。 相似文献
6.
Previous studies have reported very low rates of gluconeogenesis from lactate in sea raven (Hemitripterus americanus) hepatocytes compared to other teleosts studied. This study examines whether hepatic cell redox or lactate dehydrogenase
(LDH) characteristics may explain this observation. Sea raven hepatic optimal LDH activities (pyruvate reductase direction)
were more than 40 times less compared with rainbow trout liver values (40 vs 1914 μmol·min−1·g−1 protein). The Km(lactate) was 9.24 and 0.86 mM for sea raven and trout hepatic LDH, but the Km(pyruvate) was similar between
the two species (0.11 and 0.21 mM, respectively). These results suggested that sea raven liver LDH did not favour lactate
use and was more indicative of the mammalian M-isozyme. Gel electrophoresis showed a predominant intermediate isozyme, with
a small amount of the M-type LDH. Phosphoenolpyruvate carboxykinase (PEPCK) was localized to the mitochondrial compartment,
while there was no apparent mitochondrial glutamate-oxaloacetate transaminase (GOT) activity. No in vitro lactate flux to glucose was found in untreated, 10 mM ethanol-treated, or 3 mM NH4Cl-treated sea raven hepatocytes, although CO2 production from lactate was decreased by ethanol and increased by NH4Cl. These results provide evidence that cell redox does not limit gluconeogenesis from lactate, while low activities and the
kinetic characteristics of LDH may partially explain the low lactate gluconeogenesis reported in sea raven hepatocytes.
To whom correspondence should be addressed at University of Ottawa. 相似文献
7.
Armillaria species on tea in Kenya identified using isozyme and DNA sequence comparisons 总被引:1,自引:0,他引:1
E. Mwenje B. D. Wingfield M. P. A. Coetzee H. Nemato M. J. Wingfield 《Plant pathology》2006,55(3):343-350
The aim of this study was to identify seven Armillaria isolates obtained from diseased tea bushes in Kenya using pectic enzyme profiles, PCR-RFLP and IGS-I DNA sequence data. The combination of these identification methods confirmed the presence of three distinct Armillaria groups. One of these groups resembled Zimbabwean group I ( A. fuscipes ). The second group was phylogenetically closely related to A. mellea ssp. nipponica . The third group was different from all other African isolates examined, but had isozyme patterns, especially of pectin methylesterases (PMEs), similar to those of isolates related to A. mellea ssp. nipponica. Analyses of sequence data suggested that this group is phylogenetically closely related to A. hinnulea from Australia and New Zealand. 相似文献
8.
9.
The meiotic behavior of three tall fescue (Festuca arundinacea, 2n = 6x = 42) genotypes, giant fescue (F. gigantea, 2n = 6x = 42), and their reciprocal F1 hybrids and C1, amphiploids was evaluated to determine the parental genomic relationships. Isozyme banding patterns were used to confirm the parental identity of the hybrids and amphiploids. At meta-phase I, the parents had predominantly bivalent pairing. The hybrids had an average of 9.51 I, 16.02 II, 0.12 III, 0.02 IV, and the amphiploids had 2.17 I, 38.82 II, 0.60 III, 0.58 IV, 0.01 V—VIII. The prevalence of bivalent pairing in both hybrids and amphiploids suggested a homoeologous relationship between the six genomes, with four of the six being more closely related. Bivalent pairing in the amphiploids indicated genetic regulation of chromosome pairing. Zymograms were obtained for acid phosphatase (ACPH), alcohol dehydrogenase (ADH), glutamate oxaloacetate transaminase (GOT), malate dehydrogenase (MDH), 6-phosphogluconate dehydrogenase (6-PGD) and phosphoglucoisomerase (PGI). The three tall fescue and giant fescue parents had different zymograms for ACPH, MDH, 6-PGD and PGI; thus, the tall fescue parents of the hybrids and amphiploids could be determined based on the banding patterns of these four enzymes. Phenotypes were determined for ACPH-1, PGI-2 and 6-PGD-1. ACPH-1 may be used to follow the introgression of giant fescue chromatin into a certain tall fescue genotype. 相似文献
10.
不同剂量~(60)Co-γ射线对小麦、水稻幼苗生长的影响 总被引:9,自引:0,他引:9
用10—30KR剂量~(60)CO—γ射线处理小麦中引15、St和水稻沪B干种子、幼苗生长期胚根、子叶发育受到明显抑制.对幼苗生长的影响后期(萌发5天后)比早期(开始萌发至萌发第5天)明显,芽鞘的发育对γ射线不敏感.过氧化物酶同工酶的分析结果表明,发育受抑的小麦St、水稻沪B胚根中各增加1—2条负极酶带;发育受抑的小麦中引15、St、水稻沪B子叶中,过氧化物酶同工酶没有产生变化,而从外部形态特征上看没有变化的中引15芽鞘中比对照多2条正极带.上述结果表明,经r射线照射后,植物外部形态特征的变化与内部过氧化物酶同工酶的变化并不完全相关. 相似文献