摘要:

Some results concerning the reconstruction of barley karyotype are presented and discussed with respect to their used in genetic and breeding studies aimed at chromosome manipulation based improvement of this plant crop. It is shown that structural rearrangements can be used as cytological markers for the identification of the individual chromosomes. The different aspects of the application of cytologically marked karyotypes in the plant cytogenetics and chromosome engineering are also described. A special emphasis is laid to the use of reconstructed karyotypes as a model system in physical mapping of genes and DNA sequences.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818945

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

For several years now, intensive efforts are made in studding of different PPV strains. A range of biological, serological and molecular criteria's are applied for strain delineation of Sharka virus. This review is an attempt to synthesize the results obtained till now by different methods on PPV strain variability and differentiation.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818946

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

Tomato is one of the major vegetable crops. The wild relatives of cultivated tomato are a source of agronomically important germplasm but sexual crosses between them and the cultivated tomato are limited due to unilateral and bilateral incompatibility barriers. The aim of this review is to outline nuclear—cytoplasmic interrelations on the basis of interspecific and somatic hybridization data with the species from genus Lycopersicon. An attempt is done to summarize the published results of the studies on the mitochondrial genome of species, interspecies and somatic hybrids as well as the results concerning cytoplasmic male sterility in the genus Lycopersicon.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818935

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

The effect of Phytophthora infestons culture filtrate (CF) upon the ultrastructure of cellular organelles in potato tuber and stem derived calli has been studied. During the callus growth at light a transformation of proplastides in chloroplasts has been observed: first, continuous thylakoid membranes are formed around the starch inclusion, secondly, the assembly in grana of thylakoid took place. In CF treated calli the following changes were noted: (a) transformation of the cellular content into amorphous mass indicating the necrosis of the tissues; (b) distrophy of the nucleus; (c) disintegration of the plastid and peroxisome envelopes and of the cytoplasmic membrane, which resulted in vesicles and (d) swelling of the mitochondria followed by fragmentations of cristae and matrix lysis. CF resistant calli having normal growth presented more developed photosynthetic apparatus in stem derived calli.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818947

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

Phospholipases C are defined as enzymes that catalyze the hydrolysis of phospholipids into 1,2-diacylglycerols (or N-acylsphingosine in the case of sphingomyelin) and phosphate monoester. Some of the phospholipaes C act best towards phosphatidylcholine (sometimes referred to as PC-specific phospholipase C) and show some activity towards other phospholipids. Other phospholipases C act optimally on phosphatidyinositol (Pi-specific phospholipase C). Sphingomyelinases carry out the same type of reaction, and some of phospholipases can also utilize sphingomyeline as a substrate (11).

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818936

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

Two possibilities, based on the androgenic and gynogenic approach for development of haploid plants in vitro, were studied in the Genus Helianthus. Six F1 interspecific hybrids between the wild species H.decapetalus, H.hirsutus, H.rigidus, H.mollis, H.eggertii and H.laevigatus, and the cultivated H. animus L. have been used as donor plants for anther culture. Anthers were plated on two different callus induction media: AA medium (Alissa et al., 1985) and mod. L4M medium (Lenee P. and Chupea Y., 1985). Depending on the genotype callus induction occurred in a range of 50–100% on the mod. L4M medium and 15–60% on the AA medium. Plant regeneration and shoot multiplication were observed in the F1 hybrids of H.eggertii, H.mollis, H.decapetalus and H.rigidus after the third transfer of the calluses on the B5hormone free medium (Chandler and Beard, 1983). For inducing gynogenic development 8 wild sunflower species (H. decapetalus, H. hirsutus, H.rigidus, H. eggertii, H. laevigatas, H. ciliaris, H. x laetiflorus and H. strumosus), were pollinated with inactivated through gamma—irradiation pollen of Rf line 147. The formed embryos were cultured in vitro. Seven plants of the variant H.x laetiflorus x Rf 147, where the pollen were treated with 600 Gy gamma rays, were grown in greenhouse.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818948

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

The pulse-discharge electroporation system HPES-3 has been used to transfer the bialaphos acetyltransferase gene of plasmid pDM302 into three commercial spring wheat cultivars T2003, Huanong No. 400 and Qu an Mai No. 1. These three cultivars are widely farmed in South China. The immature embryos, collected at 12–15 days after anthesis, were electropo- rated and exposed to phosphinothricin-containing medium. Phosphinothricin-resistant embryogenic calli were induced and from these a plantlet of cultivar T2003 was recovered. PCR analysis and DNA dot blot hybridization showed that the bialaphos acetyltransferase gene was present in the cells of the transgenic plant.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818937

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

Somatic embryos obtained via microspore culture of Brassica napus have been used for study plant regeneration and double haploid production. Two mode of plant regeneration were observed: direct embryo germination and secondary adventitious buds formation. Different number of plants have been obtained for studied genotypes. Improved direct embryo development was achieved when ABA in concentration 10 μmol for 14 days at 15°C was applied. Plants were successfully colchicine treated in in vitro rooting stage by double layer media. Colchicine solution in 0.1% concentration added as a second layer for 24 hours was optimal for double haploid production and did not suppress significantly plant development. Colchicine treatment of pot plants by cuttings or roots delay 3–4 months seeds harvesting. Sufficient number of double haploid plants for breeding purposes have been obtained.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818949

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

Embryogenie response of rapeseed microspore culture from ten hybrid combinations have been evaluated. The frequency of embryo formation was strongly influenced by genotype. Bud size correlated with microspore stage of development has been determined for any of studied genotype. Embryo formation occur when microspores are predominantly in late uninucleate stage of development. Our experiments suggest that optimal density for embryo induction is between 40000 to 60000 microspore per ml. The increased embryo induction rate have been achieved when growth hormones were included in culture media.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818938

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor

摘要:

Experiments were conducted to establish the effect from infestation with varying densities of Tetranychus urticae Koch on the yield of Sandra variety cucumbers grown in greenhouses. It was establish that when experimental plants had been infested with 2 mites per leaf in their 7–8 -th leaf phase during the spring, the cucumber yield was reduced by 23.8% as compared to that of the non-infested plants, while at infestation densities of 5 and 10 mites per leaf the decrease in cucumber yield was respectively 57.8 and 66.1%. During the summer period, the same infestation densities resulted in even greater lowering of the yield, 2–6% being added to the above-mentioned yield reduction percentages.

ISSN:1310-2818    

DOI:10.1080/13102818.1997.10818950

出版商:Taylor & Francis    

年代:1997

数据来源: Taylor