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1.
Summary The relationships of Agropyron intermedium chromosomes in two wheat-Agropyron addition series were determined. Chromosome pairing behaviour revealed that the alien chromosome in lines TAF-2 and L7 of Vilmorin-A. intermedium set are homologous to the alien chromosomes in lines P and C of the Caribo-A. intermedium set respectively. Localization of alcohol dehydrogenase isozyme genes in Vilmorin-Agropyron addition line L4 and in Caribo-Agropyron line O indicated relationships with wheat chromosomes of homoeologous group 4.  相似文献   

2.
W. Hofmann 《Hydrobiologia》1980,73(1-3):255-258
Keratella cochlearis occurs in many Holstein lakes (northern Germany) as three well defined and separated forms: cochlearis, hispida, and tecta, each showing very little variation between the lakes. The present data show that the tecta form did not originate from a Lauterborn cycle.  相似文献   

3.
Summary Genotypic stability of grain yield and yield related traits was estimated for the 8 wheat-Agropyron derivatives, 441, 442, Vostock, PPG 56, PPG 56SS, 449, 450 and 441SS, together with two spring wheat controls, Drabant and Sv 01382, grown under varying watering regimes for two years. Differences among environments, genotypes and their interactions were highly significant for all traits. The genotypes X environments linear response were significant for number of spikelets per main spike, grain number per main spike and single grain weight. No significant linear responses were detected for grain yield or the rest of yield related traits. Deviations from linear responses were highly significant for all traits under study. Grain yield stability was not associated with the stability of yield components. PPG 56SS was identified as the stable variety with the highest mean grain yield per plant under the severe stress environment. Mean grain yields in the severe stress environment were correlated with the genotypic stability parameter . The severe stress environment was recognized as the optimum test environment. The study revealed a shift in the association between grain yield per plant and its components under the varying environments.  相似文献   

4.
Four glycosidases were analyzed in 10 mm apical segments prepared from growing roots (15 mm) of Zea mays L. The pH optima were found to be 5.8 for -glucosidase, 4.4 for -galactosidase, 6.4 for -glucosidase and 6.0 for -galactosidase. The -glucosidase showed 4-fold higher activity than the -galactosidase. The distribution of the -glucosidase activity was signifcantly different from that of the -galactosidase, -glucosidase and -galactosidase.Abbreviations -Glu -glucosidase - -Gal -galactosidase - -Glu -glucosidase - -Gal -galactosidase  相似文献   

5.
Zeins from Zea mays L cv. Maya and coixins from Coix lacryma-jobi L. cv. Adlay were fractionated to obtain -, -, and -zein and -, -, and -coixin. The -coixins were composed of 4 polypeptide classes of 27 kDa (C1), 25 kDa (C2), 17 kDa (C4) and 15 kDa (C5) with solubility properties very similar to those of the 22 kDa and 19 kDa -zeins. Like the -zeins, the C1 and C2 -coixins corresponded to 80% of total Coix prolamins. The fraction corresponding to -coixin contained only one protein band of 22 kDa (C3). This coixin fraction has solubility properties similar to those of -zein and represents 15% of the total coixin. The -zein fraction was composed of a major 17 kDa protein band, while the -coixin fraction consisted of a mixture of - and -coixins.Polyclonal antibodies raised against C1 recognized C1 and C2 and cross-reacted strongly with the 22 kDa -zein, as did C4 and C5 antisera. The antiserum against -coixin showed strong cross-reaction with -zein. The homology between coixins and zeins was further investigated by using Southern hybridization analyses. The genomic DNA of maize and Coix were digested with several restriction enzymes and probed with cDNA clones representing 19 and 22 kDa -zeins as well as the 28 and 16 kDa -zeins. The Coix genome showed complex cross-hybridization sequences with the 22 kDa -zein cDNA, while no cross-hybridization was observed with the 19 kDa cDNA clone. The cDNA clone representing the 28 kDa -zein cross-hybridized with only one band of Coix genomic DNA, in contrast to the three bands observed in maize. This same Coix sequence also cross-hybridized with the cDNA clone representing the 16 kDa -zein. The relevance of these findings are discussed in the context of the origin of zein and coixin genes.  相似文献   

6.
Regeneration of adventitious shoots from leaves of several in vitro-cultured Rubus genotypes was affected by media components and incubation conditions. Leaves cultured at 20°C with a photosynthetic photon flux (PPF) of 40 mol m-2 s-1 had a higher regeneration frequency and more shoots per regenerating leaf than ones cultured at 25°C with a PPF of either 40 or 80 mol m-2 s-1. Thidiazuron (TDZ) was significantly more effective than benzyladenine. Medium containing 1 M TDZ had the highest percentage regeneration for leaves of Autumn Bliss, Canby, Summit and Sentry red raspberries, whereas leaves of MD-ETCE-1 blackberry hybrid responded more to 10 M TDZ. Higher regeneration frequencies were obtained with 0.5 M indolebutyric acid (IBA) than with 1 M, but no significant difference was observed between 0.5 M and no IBA in other experiments. More shoots per regenerating leaf formed on Murashige and Skoog (MS) and N6 media, than on half-strength MS, Anderson, or Woody Plant media for all genotypes tested. The youngest two expanding leaves near the shoot apex were the most regenerative and yielded the highest number of shoots per regenerating leaf.Abbreviations AND Anderson (1980) - BA benzyladenine - IBA indolebutyric acid - MS Murashige & Skoog (1962) - N6 Chu et al. (1975) - NAA naphthaleneacetic acid - PPF photosynthetic photon flux - TDZ thidiazuron (N-phenyl-N'-1, 2, 3-thiadiazol-5-ylurea) - WPM Woody Plant Medium [Lloyd & McCown (1980)]  相似文献   

7.
Summary Tobacco plants (Nicotiana tabacum L.) of four varieties (Badischer Burley, White Burley, Techne, Kupchunos) were raised at different temperatures and daylengths and the effect of genotype on embryogenic pollen grain formation in situ and on pollen plant formation in anther and pollen cultures from these plants was studied. Genotype controlled embryogenic pollen grain and pollen plant formation by defining productivity under standard growth conditions (long days at 24 °C). Kupchunos was the most productive variety, followed by White Burley, Techne, and Badischer Burley. Furthermore, genotype defined which environmental factor was able to affect embryogenic pollen grain and pollen plant formation and also to which degree. In anther cultures, in addition to these effects, genotype controlled the formation of (an) inhibitory substance(s) in the anther wall in interaction with the plant growth conditions. In Badischer Burley and Techne, inhibitor action could be prevented by isolation of the pollen after one week of anther culture. Finally, direct pollen cultures in Badischer Burley and Techne produced embryos were only when the pollen was isolated from nearly mature anthers, while in White Burley and Kupchunos, embryos also produced at earlier stages and at higher yields. This indicated that genotype controls the time when the embryogenic pollen grains become ready to divide. The results are discussed in relation to strategies to overcome recalcitrance of species and genotypes.  相似文献   

8.
Expression of the RI regulatory subunit of protein kinase A type I is increased in human cancer cell lines, in primary tumors, in cells after transformation, and in cells upon stimulation of growth. Ala99 (the pseudophosphorylation site) of human RI was replaced with Ser (RI-p) for the structure-function analysis of RI. MCF-7 hormone- dependent breast cancer cells were transfected with an expression vector for the wild-type RI or mutant RI-p. Overexpression of RI-P resulted in suppression of protein kinase A type II, the isozyme of type I kinase, production of kinase exhibiting reduced cAMP activation, and inhibition of cell growth showing an increase in G0/G1 phase of the cell cycle and apoptosis. The wild-type RI overexpression had no effect on protein kinase A isozyme distribution or cell growth. Overexpression of protein kinase A type II regulatory subunit, RII, suppressed RI and protein kinase A type I and inhibited cell growth. These results show that the growth of hormone-dependent breast cancer cells is dependent on the functional protein kinase A type I.  相似文献   

9.
Cryopreservation has been recognized as a practical and efficient tool for long-term storage of vegetatively propagated plants. This study was conducted to investigate effects of modified vitrification techniques on cryopreservation of potato. In vitro plants of potato cultivars Superior and Atlantic were cold acclimated, and axillary buds were precultured, osmoprotected, exposed to PVS-2 solution, plunged into liquid nitrogen, thawed, and finally planted in the regeneration medium. In the modified vitrification technique an ice-blocking agent, Supercool X1000, was added with PVS-2 solution. Cold acclimation affected survival of cryopreserved shoot tips, and the highest survival (46.7%) was obtained after 3 weeks of acclimation at 10°C. Shoot tips exposed to 2M glycerol plus 0.6M sucrose for 40 min gave 51.5% and 11.7% survival in Atlantic and Superior at 10°C, respectively. Cold acclimated and osmoprotected shoot tips were dehydrated with PVS-2 containing different concentrations of Supercool X1000 prior to a plunge into liquid nitrogen. Treatments with 0.1% and 1% of Supercool X1000 significantly improved survival by 55% in Superior and 71.3% in Atlantic, respectively. After cryopreservation, vitrified shoot tips resumed growth within a week in a medium (1 mg l–1 GA3, 0.5 mg l–1 zeatin, and 0.1 mg l–1 IAA) with a low level of Pluronic F-68 (0.005%) and survival was 33.7% higher in Atlantic and 14.7% higher in Superior than the control (without Pluronic F-68).  相似文献   

10.
Salmon gonadotropin (GTH II) is a heterodimeric glycoprotein hormone ( and II subunits), serving as a maturational GTH, and is produced in a specific gonadotropic cell-type (GTH II-cells) containing small granules and large globules. In trout GTH II-cells, double immunolabeling for the - and II-subunits shows that colocalization of the - and II-immunolabeling is confined to the small granules, indicating storage of functional GTH II. On the other hand, -immunolabeling is absent in the large globules, even though II labeling is abundant throughout the period of seasonal gametogenesis. The -specific antiserum recognizes the intact -subunit as well as the reduced and deglycosylated -subunits by immunoblotting. These results indicate that an accumulation of the II-subunit is specifically generated in the large globules of these cells. In fact, with sexual maturity, the quantity of II-subunits becomes elevated in the trout pituitary due to a marked increase in GTH II-cells containing many large globules. However, the derivation and function of the large globules and the fate of their contained II-subunits remains unknown.  相似文献   

11.
Our objectives were to quantify and compare soil CO2 efflux of two dominant soil types in an old-growth neotropical rain forest in the Atlantic zone of Costa Rica, and to evaluate the control of environmental factors on CO2 release. We measured soil CO2 efflux from eight permanent soil chambers on six Oxisol sites. Three sites were developed on old river terraces (old alluvium) and the other three were developed on old lava flows (residual). At the same time we measured soil CO2 concentrations, soil water content and soil temperature at various depths in 6 soil shafts (3 m deep). Between old alluvium sites, the two-year average CO2 flux rates ranged from 117.3 to 128.9 mg C m–2 h–1. Significantly higher soil CO2 flux occurred on the residual sites (141.1 to 184.2 mg C m–2 h–1). Spatial differences in CO2 efflux were related to fine root biomass, soil carbon and phosphorus concentration but also to soil water content. Spatial variability in CO2 storage was high and the amount of CO2 stored in the upper and lower soil profile was different between old alluvial and residual sites. The major factor identified for explaining temporal variations in soil CO2 efflux was soil water content. During periods of high soil water content CO2 emission decreased, probably due to lower diffusion and CO2 production rates. During the 2-year study period inter-annual variation in soil CO2 efflux was not detected.  相似文献   

12.
A simple and rapid pea regeneration procedure was developed. An average of up to 20 shoots formed from hypocotyl explants of cvs. Sugar Ann and Patriot cultured on Murashige and Skoog basal medium supplemented with 0.5 or 1.0 M thidiazuron (N-phenyl-N-1,2,3-thiadiazol-5-ylurea). Hypocotyls of Puget and Sugar Daddy did not respond. Regenerated shoots rooted rapidly when cultured on Murashige and Skoog basal medium containing either 2.0 M -naphthaleneacetic acid or 1.0–2.0 M indole-3-butyric acid. Seeds were harvested from regenerated plants after only 9–11 weeks.Abbreviations BAP 6-benzyladenine - 2,4-d 2,4-dichlorophenoxy acetic acid - GA3 gibberellic acid - IBA indole-3-butyric acid - MS Murashige and Skoog (1962) medium - NAA -naphthaleneacetic acid - TDZ thidiazuron (N-phenyl-N-1,2,3-thiadiazol-5-ylurea)  相似文献   

13.
Summary We have synthesized 2(3)-O-(glycyl)-adenosine-5-(O-methylphos-phate), an analogue of the 3-terminus of aminoacylated tRNA. A 0.4M solution of this compound maintained at pH 8.2, yields 5.5% of diglycine and 11.5% of diketopiperazine, in addition to the hydrolysis products glycine and adenosine-5-(O-methylphosphate). Under the same conditions, glycine ethyl ester reacts much more slowly, but ultimately gives similar yields of diglycine and diketopiperazine.The aminolysis of 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) by free glycine is relatively inefficient, but serine reacts 20 times more rapidly and yields up to 50% of N-glycylserine. The prebiotic significance of these reactions is discussed.Abbreviations MepA adenosine-5-(O-methylphosphate) - MepA-gly 2(3)-O-(glycyl)-adenosine-5-(O-methylphosphate) - MepA-bis-gly 2,3-O-(bis-glycyl)-adenosine-5-(O-methylphosphate) - DKP diketopiperazine - gly Et glycine ethyl ester - gly-ser N-glycylserine - O-gly-ser O-glycylserine - O-(gly)-gly-ser O-(glycyl)-glycylserine - Boc-gly N-tert-butyloxycarbonylglycine - MepA-Boc-gly 2(3)-O-(Boc-glycyl)-adenosine-5-(O-methylphosphate) - MepA-bis-Boc-gly 2,3-O-(bis-Boc-glycyl)-adenosine-5(O-methylphosphate) - (gly)2 diglycine - (gly)3 triglycine  相似文献   

14.
A novel syrup containing neofructo-oligosaccharides was produced from sucrose (Brix 70) by whole cells of Penicillium citrinum. The efficiency of fructo-oligosaccharides production was more than 55% and those of the main carbohydrate components, 1-kestose (Fruf 21Fruf 21 Glc), nystose (Fruf 21Fruf 21 Fruf 21 Glc) and neokestose (Fruf 26 Glc12 Fruf), were 22, 14 and 11%, respectively.  相似文献   

15.
The preparation of benzyl 2,3,6,2,6-penta-O-benzyl--d-lactoside, which is a key intermediate for chemical synthesis of oligosaccharide components of glycosphingolipids, was achieved by an improved method. The 3-O-p-methoxybenzyl and 3-O-methyl derivatives were prepared from benzyl 2,3,6,2,6-penta-O-benzyl--d-lactoside through stannylation. By using benzyl -d-lactoside as starting material, benzyl 3-O-methyl-, 3-O-benzyl- and 3-O-p-methoxybenzyl--d-lactoside were regioselectively synthesized using the same procedure.  相似文献   

16.
Summary In the Far East two types of -thalassemia genes, namely -thalassemia1 (-thal1) and -thalassemia2 (-thal2) exist. Definite diagnosis of the -thal1 and -thal2 traits is very difficult because their hematological findings are minimally abnormal or normal. This study attempts to characterize the heterozygotes by hemoglobin chain synthesis in reticulocytes from obligatory cases of the -thal1 and -thal2 traits. Twelve parents of babies with hemoglobin Bart's hydrops fetalis (obligatory -thal1 trait) had the mean total radioactivity / ratio of 0.76±SD 0.04, while that of 7 normal controls was 1.06±SD 0.04. The / globin chain ratios of 16 cases, who were either parents or offspring of patients with hemoglobin H disease, were found to segregate into 2 groups, i.e. 0.78±SD 0.03 (10 cases) and 0.92±SD 0.03 (6 cases), probably representing the -thal1 and -thal2 traits respectively. The hematological data of the first group showed definite hypochromic microcytic red cells, similar to thoseof the parents of the hydrops. The second group had significantly higher mean corpuscular hemoglobin than the first group, compatible with -thal2 trait. Our globin chain synthesis study thus appears to be capable of discriminating normal, -thal1 and -thal2 traits.A preliminary report of the results was presented at the XV Congress of the International Society of Haematology, Israel, September, 1974.  相似文献   

17.
Summary Meiotic pairing in Triticum turgidum cv. Ma (4x) with a mean chiasmata frequency of 27.16 per cell was compared with chiasmata frequencies in its hybrids with several triticale strains, Chinese Spring wheat and its addition lines for Imperial rye chromosomes 4R and 6R. In hybrids between Ma and x Triticosecale cv. Rosner the chiasmata frequency was marginally reduced by an average of 1.25%, by 8.8% in hybrids with x Triticosecale cv. DRIRA HH and by 6.7% with DRIRA EE (lacking 90% telomeric heterochromatin from chromosome arm 7RL). In pentaploid hybrids between Ma and T. aestivum cv. Chinese Spring the reduction was an average of 10.30%, while addition lines with rye chromosome 6R reduced chiasmata frequencies by an average of 7.4% and rye addition line for 4R showed the greatest depression in chiasmata frequency in hybrids by a 25.04% reduction. An interchange difference involving long chromosome segments was observed between Ma and Rosner.Contribution No. 819 Ottawa Research Station  相似文献   

18.
The inheritance of host plant resistance and its effect on the relative infection efficiency for leaf blast was studied in the crosses IR36/CO39 (partially resistant × highly susceptible) and IR36/IR64 (both partially resistant). On the natural scale, gene action appeared multiplicative. After log transformation, additive effects described most of the genetic variation in the cross IR36/CO39, while additive and dominance effects were about equal in magnitude in the cross IR36/IR64. Dominance was towards increased resistance. No transgressive segregation occurred in the cross IR36/CO39. The number of genes that reduce lesion number was estimated to be zero in CO39 and five or more in IR36. The cross IR36/IR64 showed transgressive segregation in both directions, and IR36 and IR64 each contain at least one gene that is not present in the other cultivar. The heritabilities (narrow sense) in the F2 were low (range 0.06–0.16), while narrow sense heritabilities based on F3 lines were much higher (range 0.41–0.68). Lesion numbers in F3 lines were reasonably correlated with those in F5 progenies derived from the same F2 plant (r was±0.6 in both crosses). Partial resistance can be effectively improved by selecting the most resistant plants from the most resistant F3 lines.  相似文献   

19.
Summary The establishment and development of vesicular-arbuscular mycorrhizal (VAM) fungi were studied in three cultivars of potato, which differed in susceptibility to Late blight, in a field experiment on a lateritic sandy-loam during two growing seasons (1980 and 1981). The cultivars SSC 1174 (highly resistant) and Kufri Jyoti (resistant) showed an earlier establishment and more rapid development of VAM fungi than up-to-date (highly susceptible). The first mycorrhizal infection in both SSC 1174 and Kufri Jyoti was observed after 12 days in 1980 and 8 days in 1981, whereas in up-to-date it was observed after 19 and 12 days respectively. The mycorrhizal infection increased with the age of the plants in all the three cultivars.  相似文献   

20.
Summary The inheritance of resistance to whitebacked planthopper Sogatella furcifera (Horvath) was studied in 21 rice varieties. Reactions of F1; F2 and F3 progenies of the crosses of 21 resistant varieties with the susceptible variety TN 1 revealed that a single dominant gene governs resistance in Mushkan 41, Santhi, Siahnakidar 195, SM2-34, Tirisurkh 251, Zirijowaian 245, 18, 24A, 39, 76 S, 78, 180, 213 B, 267, 293, CI 6037-4, NP97, S39 JKW and Bansphul. In varieties 65 and 274 A, resistance is governed by one dominant and one recessive gene which segregate independently of each other. Tests for allelism with the Wbph 1 gene originally identified in N 22 revealed that the dominant gene present in all the test varieties is the same as Wbph 1. Further studies are required to determine the allelic relationships of the recessive gene found in varieties 65 and 274 A.  相似文献   

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