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411.
412.
Developmental stages of Meloidogyne javanica were successfully released from roots by treatment with commercially available cellulase and pectinase. The average percentage recovery of nematode developmental stages from Dolichos lablab, Elymus glaucus, and Lycopersicon esculentum were as follows: eggs = 526%, J2 = 272%, J3 = 783%, J4 = 549%, adult females = 285%, and total = 425%, expressed as percentages of the counts obtained from stained roots spread on glass plates. Root digestion was more accurate and sensitive in detecting low numbers of nematodes in roots than was the glass plate method. No simple linear, quadratic, or cubic relationship was found between the two methods that would allow a conversion factor to be developed. 相似文献
413.
414.
Braulio Esteve-Zarzoso María José Peris-Torán Daniel Ramón Amparo Querol 《Antonie van Leeuwenhoek》2001,80(1):85-92
The sequences of the internal transcribed spacers (ITS regions) and the 5.8S rRNA gene, together with the electrophoretic karyotypes of 27 strains representative of the six species belonging to the genus Hanseniaspora, were examined. From the analysis of the 5.8S rRNA gene and the ITS regions, the genus Hanseniaspora is monophyletic and can be divided into two subgroups. This subdivision was supported by electrophoretic chromosome patterns. Hanseniaspora guilliermondii, H. uvarum and H. valbyensis show 6–7 bands (8 to 9 chromosomes), while the second group comprises the species H. occidentalis, H. osmophila and H. vineae which have only 5 chromosomes. 相似文献
415.
Two novel dihydroanthracenones, menamesone A and menamesone B, and two known hydronaphthalenones of a rare type, rubiasins B and C, have been isolated from the roots of Plocama pendula, a paleoendemism of the Canary Islands. 相似文献
416.
417.
Alejandro Araya Rodolfo Amthauer Gloria Leon Manuel Krauskopf 《Molecular & general genetics : MGG》1984,196(1):43-52
Summary The mitochondrial genome from Cyprinus carpio oocytes is a 10.5 megadalton, circular DNA molecule. The carp mitochondrial DNA was cloned in pBR325. Three recombinant plasmids accounted for the entire genome. Mapping of this DNA using 11 different restriction endonucleases is reported here. Both the large and small rRNA genes were then localized using Southern blot analysis. The subunit I of the cytochrome oxidase, the cytochrome b, the tRNAGlu and the URF 4 genes were localized by nucleotide sequence analysis and homology studies with human mtDNA.Our results suggest that a similar gene order has been maintained in the mitochondrial genomes of Chordata and support the hypothesis of a common ancestor for all vertebrate organelle genomes.This study constitutes the first report on the genome organization of a fish mtDNA and provides information for further investigation in connection with sequence determination, replication, and gene expression in carp mitochondria.This work was supported by proyect RS-82-21 from the Universidad Austral de Chile and Grant No 1116 from Fondo Nacional de Desarrollo Cientifico y Tecnologico 相似文献
418.
Summary Seasonal growth dynamics of the root and shoot systems of dominant shrubs of the Chilean matorral were studied. In some species root and shoot activity were synchronous, while in others production of fine roots was observed prior to bud burst and shoot elongation. Biomass production of new roots was significantly higher in spring than in autumn. Maximum biomass of dead roots was concomitant with the maximum amounts of litter under the canopy. 相似文献
419.
Since the establishment of abalone farming, there has been an increase in the demand for Macrocystis as a food source. Therefore, the pressure on natural stock has also augmented and the sustainability of the actual harvesting
practices has been questioned. In this article, an attempt to farm Macrocystis pyrifera by zoospores in northern Chile is described; initially under laboratory conditions and subsequently by cultivation in the
sea. The experiments were executed during 1 year and two different cultivation methodologies were used: a direct and an indirect
method. A maximum frond length of 175 cm was reached and 22 kg m−1of rope was produced after 120 to 150 days of cultivation in the sea. The algae grew under both methodologies, and no differences
in algal length and biomass were detected between the two cultivation systems. However, the direct culture method can be recommended
for productive and practical reasons. 相似文献