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31.
Krishna P. Kollipara Ram J. Singh Theodore Hymowitz 《American journal of botany》1995,82(9):1104-1111
We investigated the use of a monoclonal antibody (MAb 238) to the soybean Bowman-Birk inhibitor (BBI) to verify and understand the intergenomic relationships among the wild perennial Glycine species. Competitive enzyme linked immunosorbent assay and western blot screening studies revealed that the accessions of B-genome (G. latifolia, G. microphylla, and G. tabacina, 2n = 40) and C-genome (G. curvata and G. cyrtoloba) species did not contain the MAb 238 crossreactive proteins (BBI-nulls). By contrast, all the A-genome (G. argyrea, G. canescens, G. clandestina, and G. latrobeana), E-genome (G. tomentella, 2n = 38), and F-genome (G. falcata) species, G. arenaria (genome unknown), and the polyploid (2n = 78,80) G. tomentella accessions were BBI-positive. The D-genome G. tomentella (2n = 40) and tetraploid G. tabacina (2n = 80) contained both BBI-null and BBI-positive type accessions. Among the recently described species, G. hirticaulis (2n = 40), G. lactovirens, and G. pindanica contained the MAb 238 crossreactive proteins while G. albicans did not. Glycine hirticaulis, G. pindanica, and G. tomentella (2n = 38) displayed highly similar MAb 238 crossreactive isoelectric focusing banding patterns, indicating that they are genomically close to each other. Glycine hirticaulis was found to have both diploid (2n = 40) and tetraploid (2n = 80) cytotypes. We demonstrated that the MAb 238 was specific to the trypsin inhibitor domain of the BBI. The MAb 238 clearly reflected all the previously established relationships in the genus Glycine, validating its use as a genome marker. 相似文献
32.
Maira Oropeza Palmira Guevara Eva de García José Luis Ramírez 《Plant Molecular Biology Reporter》1995,13(2):182-191
Somaclonal variants resistant to sugarcane mosaic virus (SCMV) were obtained from susceptible sugarcane cv PR62258 through
somatic embryogenesis by increasing the number of subcultures of the embryogenic callus tissue in MS medium with 3 mg/L 2,4-dichlorophenoxyacetic
acid. Transfers were made at 30-day intervals for 1, 2 or 3 subcultures. Two somaclones, namely AT626 and BT627, were selected
by their resistance to SCMV. These subclones have maintained the resistance trait over seven years of testing in the field.
In this report we identified the somaclonal SCMV resistant variants from the maternal line and the nonresistant somaclones,
using the RAPD technique. 相似文献
33.
G. Ramírez-Zarzosa F. Gil R. Latorre A. Ortega A. García-Alcaráz E. Abellán J. M. Vázquez O. López-Albors A. Arencibia F. Moreno 《Cell and tissue research》1995,280(2):217-224
Fibre-type differentiation of the lateral musculature has been studied in Sparus aurata (L.) and Dicentrarchus labrax (L.) during larval development. Histochemical and ultrastructural techniques show two presumptive muscle layers and two germinative zones of presumptive myoblasts. At hatching, myotomal muscle consists of a monolayer of thin undifferentiated cells near the skin (first germinative zone) overlying another mono-layer of small diameter fibres extending hypaxially and epaxially away from the transverse septum. Below this, there is a much thicker, deep layer of fibres, generally large in diameter and polygonal in shape. The presumptive myoblasts are located between these two layers of fibres in the second germinative zone. Initially, the superficial and deep muscle fibres show high and low myosin ATPase activity, respectively. Both layers grow by generating new fibres from the two mentioned germinative zones. At the end of larval life, the superficial layer changes its histochemical profile from high to low myosin ATPase activity and, at the same time, intermediate or pink muscle fibres can be observed by oxidative activity (the NADH-TR reaction). Morphometric analysis shows a significant increase in mean fibre diameter during successive ages, as shown by the Student's t-test (hypertrophic growth). Skewness and kurtosis values of fibre diameters point to the generation of a new fibre population from the germinative zones (hyperplastic growth). 相似文献
34.
P. Ram 《Biocontrol Science and Technology》1995,5(3):329-338
Strains of Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae) collected from six different geographical regions in Eurasia were compared in terms of their biological and morphological characteristics and electrophoretic patterns. Significant differences were observed between the strains for biological characteristics such as the proportion of female progeny, developmental period, longevity, proportion of adults emerging and fecundity. Strains from the Altai region in Russia were more fecund at all hygrothermal conditions in which they were reared (27 C, 80% relative humidity (RH); 27 C, 40% RH; 23 C, 80% RH; and 23 C, 40% RH). Poor adult emergence took place at 27 C and 40% RH in strains from Moldavia and Slovakia. Morphological examination of male antennae showed that strains from Moldavia and Slovakia had the highest ratio of the length of antennal hairs to the maximum width of flagellum. The patterns of esterases after electrophoresis indicated that strains differed in the mobility and intensity of esterase bands. Electrophoretic and morphological relationships among the strains did not correspond with their biological relationships. The possibility of the use of strains from the Altai region in Russia in biocontrol programmes in southern parts of Europe is discussed. 相似文献
35.
Five novel representatives of the yeast genus Candida isolated from advanced stages of wood degradation from fallen trunks of Eucryphia cordifolia Cav., Laurelia sempervirens Weim., Laurelia philippiana Weim., Nothofagus dombeyii (Mirb.) Blume, and Nothofagus obliqua (Mirb.) Blume, in the evergreen rainy Valdivian forest of southern Chile, are described and illustrated. They clearly differ from all accepted Candida species to warrant their establishment as five new species of yeasts: Candida coipomensis sp. nov., Candida ralunensis sp. nov., Candida laureliae sp. nov., Candida osornensis sp. nov., and Candida llanquihuensis sp. nov. 相似文献
36.
Four unusual Apiotrichum, isolated from decayed wood of Eucryphia cordifolia Cav., Nothofagus obliqua (Mirb.) Blume, and Laurelia sempervirens Wein., one of which was also isolated from the intestinal tract of Scaptomyza multispinosa Malloch (Diptera), are described and illustrated. These species differ from all the accepted Apiotrichum species (1–3) to warrant their establishment as four new species: Apiotrichum eucryphiae, Apiotrichum osvaldii, Apiotrichum futronensis and Apiotrichum nothofagi. 相似文献
37.
Two unusual species of Candida and one variety of one of them, isolated from decayed wood (palo podrido) (12) in the ultimate stages of degradation, are described and illustrated. They differ sufficiently from all accepted Candida species to warrant their establishment as two new species and one variety: Candida railenensis, Candida bertae, and Candida bertae var. chiloensis.The DNA base composition of these yeasts was not calculated, since our laboratory is not properly equipped for that purpose. 相似文献
38.
Two new compounds G and H isolated from the roots of Costus speciosus have been characterized as 8-hydroxytriacontan-25-one and Me tritriacontanoat 相似文献
39.
Characterization and Translation of Poly(A)+RNA from Wounded and Crown Gall Tissues of Potato Tubers
Poly(A)+ and poly(A)RNA from wounded potato tuber tissuesand crown gall tumors were separated from total RNA by oligodeoxythymidylicacid-cellulose affinity chromatography. The poly(A)+RNA wascharacterized by sucrose density gradient centrifugation, hybridizationwith 3(H)polyuridylic acid [Poly(U)] and in vitro translationin a rabbit reticulocyte lysate system. The tumor poly(A)+RNAwas a heterodisperse mixture from 3.5S to 35S. Upon poly(U)hybridization of the gradient fractions two major hybridizationpeaks at 7S and 21S and two peaks at 11S and 16S appeared. Inan in vitro translation system the poly(A)+RNA programmed thesynthesis of 23 different polypeptides of 9,000 to 79,800 daltonsmolecular weight as determined by SDS-polyacrylamide gel electrophoresis.The 21S poly(A)+RNA was about 5 times more active in in vitroprotein synthesis than the 7S poly(A)+RNA. The poly(A)+RNA from wounded tissues was also heterodisperse(from 4.5S to 31S) with a modal peak at 18S. This RNA codedfor at least 28 polypeptides, which were different from thoseof crown gall tumor tissues. On a per unit poly(A)+RNA basis the tumor RNA was slightly moreactive in translation than that from wounded tissues. The translationof tumor poly(A)+RNA was completely blocked by 0.5 mM 7-methylguanosine5'-phosphate, but not by 7-methylguanosine, suggesting the presenceof a 5'-cap structure. (Received May 15, 1982; Accepted June 30, 1982) 相似文献
40.
Four new species of Penicillium Link ex Fries are described and illustrated. All of them but one have been isolated from the atmosphere in Madrid, Spain. They clearly differ from all species of the genus described so far and are, therefore, described and proposed as new taxa: Penicillium aurantio-flammiferum sp. nov., Penicillium gallaicum sp. nov., Penicillium granatense sp. nov., and Penicillium ilerdanum sp. nov. 相似文献