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71.
NO Agbenin AM Emechebe PS Marley 《Archives Of Phytopathology And Plant Protection》2013,46(4):319-326
Fusarium wilt and root-knot are important diseases of tomato. The use of chemical is becoming less appealing because of the health implications. Also, the chemicals required are often not within the reach of farmers in most of the developing part of the world. This research is aimed at finding an alternative mode of control. Tomato variety Roma VF inoculated with Meloidogyne and Fusarium were treated with 2 g/kg soil neem seed powder in the screenhouse and 2 Mg ha ? 1 in the field. An untreated and Furadan treated plot in the field served as control. Neem seed powder significantly reduced the disease severity of Fusarium and root-knot in both screenhouse and field. Results suggest the possible use of neem seed powder for control of the root-knot nematodes - Fusarium wilt disease complex. 相似文献
72.
Background
The introduction of transgenes into plants may cause unintended phenotypic effects which could have an impact on the plant itself and the environment. Little is published in the scientific literature about the interrelation of environmental factors and possible unintended effects in genetically modified (GM) plants.Methods and Findings
We studied transgenic bread wheat Triticum aestivum lines expressing the wheat Pm3b gene against the fungus powdery mildew Blumeria graminis f.sp. tritici. Four independent offspring pairs, each consisting of a GM line and its corresponding non-GM control line, were grown under different soil nutrient conditions and with and without fungicide treatment in the glasshouse. Furthermore, we performed a field experiment with a similar design to validate our glasshouse results.The transgene increased the resistance to powdery mildew in all environments. However, GM plants reacted sensitive to fungicide spraying in the glasshouse. Without fungicide treatment, in the glasshouse GM lines had increased vegetative biomass and seed number and a twofold yield compared with control lines. In the field these results were reversed. Fertilization generally increased GM/control differences in the glasshouse but not in the field. Two of four GM lines showed up to 56% yield reduction and a 40-fold increase of infection with ergot disease Claviceps purpurea compared with their control lines in the field experiment; one GM line was very similar to its control.Conclusions
Our results demonstrate that, depending on the insertion event, a particular transgene can have large effects on the entire phenotype of a plant and that these effects can sometimes be reversed when plants are moved from the glasshouse to the field. However, it remains unclear which mechanisms underlie these effects and how they may affect concepts in molecular plant breeding and plant evolutionary ecology. 相似文献73.
L V Kalinina 《Tsitologiia》1968,10(12):1588-1597
74.
A phylogenetic analysis of sex-chromosomal zinc-finger genes (Zfx and Zfy)
indicates that the genes have not evolved completely independently since
their initial separation. The sequence similarities suggest gene conversion
in the last exon between the duplicated Y-chromosomal genes Zfy-1 and Zfy-2
in the mouse. There are also indications of conversion (or recombination)
between the X- and Y-chromosomal genes in the crab- eating fox and in the
mouse. The method for estimating synonymous and nonsynonymous substitutions
is modified by incorporating the substitutions in the twofold-degenerate
sites in a novel way. The estimates of synonymous substitutions support the
generation-time hypothesis in that the obtained rates are higher in mice
(by a factor of 4.7) than in humans and higher in the Y-chromosomal genes
(by a factor of 1.9) than in the X-chromosomal genes.
相似文献
75.
Studies have been made on viability and hereditary properties of the progeny of amoebae after micrurgical coercions (sectioning of cells, suction of cytoplasm) during metaphase and early anaphase. The progeny of the fragments as well as of the cells with the reduced bulk of the cytoplasm exhibits unusual methionine resistance. Possible mechanism of the observed phenomemon are discussed. 相似文献
76.
A set of plasmids carrying different initiator codons--either AUG, or GUG, or UUG, or CUG (as a control) in the hybrid gene lacIZ--was constructed by using synthetic oligonucleotides. GUG and UUG codons were demonstrated to be 2-3 times less effective than AUG in translation initiation. Furthermore, the correlation between the efficiencies of different initiator codons in translation initiation proved to vary, depending on the phase of bacterial growth. The rarely occurring usage in nature of the initiator codons GUG and UUG is supposed to be due to the particular role played by the initiator triplets in regulation of gene expression. 相似文献
77.
R V Petrov L V Koval'chuk A R Kalinina A S Pavliuk T Iu Ul'ianova 《Biulleten' eksperimental'no? biologii i meditsiny》1989,107(6):713-715
The methodological aspects of Lak-cells functional activity test were determined. NK-resistance of P-815 culture cells and NK-sensitive K-562 cells were used as target cells. The highest cytotoxicity level was registered at the 5-th day of culturing MNC with rIL-2 at the final concentration (100 U/ml). The method developed was used for testing healthy donors group and group of patients with IL-2 dependent immunodeficiency (ophthalmic herpes). Data obtained show the significant decrease of LAK-cells functional activity of patients in comparison with healthy donors. Thus, the developed method is recommended for complex estimation of immune status of patients with IL-2-dependent immuno deficiency. 相似文献
78.
Kalinina IaM 《T?Sitologii?a i genetika》2006,40(5):21-27
Using confocal microscopy the organization of tubulin cytoskeleton including endoplasmic and cortical microtubules (CMTs) has been studied in epidermal and cortical cells of the different growth zones of main root of Brassica rapa L. 6-days-old seedlings in control conditions and under clinorotation. It was shown that changes in CMTs orientation occured only in the distal elongation zone (DEZ). In the control, CMT arrays oriented transversely to the root long axis. Under clinorotation appearance of the shorter randomly organized CMTs was observed. Simultaneously, a significant decrease in the cell length in the central elongation zone (CEZ) under clinorotation was detected. It is suggested that the decline of anisotropic growth typical for CEZ cells is connected with CMTs disorientation under clinorotation. 相似文献
79.
Isocitrate and isopropylmalalte dehydrogenases are homologous enzymes important for the cell metabolism. They oxidize their substrates using NAD or NADP as cofactors. Thus, they have two specificities, towards the substrate and the cofactor, appearing in three combinations. Although many three-dimensional (3D) structures are resolved, identification of amino acids determining these specificities remains a challenge. We present computational identification and analysis of specificity-determining positions (SDPs). Besides many experimentally proven SDPs, we predict new SDPs, for example, four substrate-specific positions (103Leu, 105Thr, 337Ala, and 341Thr in IDH from E. coli) that contact the cofactor and may play a role in the recognition process. 相似文献
80.
M. V. Kalinina P. A. Zadorozhnyi N. A. Vinnikova 《Russian Journal of Developmental Biology》2009,40(3):176-182
The sexual cycle of Japanese mitten crab Eriocheir japonica (de Haan, 1835) in its northern range in water bodies of the Primorye proved to have specific properties including changed seasonal dynamics of gonad maturity stages, delayed spawning period, and reduced breeding season. The ovary color regularly changed during the gonad growth in females, which was accompanied by an increase in total carotenoid content from 1.4 to 22.2 mg/100 g tissue and by changes in the proportion of major pigments. The relative content of the carotene fraction notably decreased and that of astaxanthin slightly decreased during gonad maturation. The revealed changes in carotenoid levels in the ovary point to the activity and significance of pigment metabolism in the reproductive cycle of E. japonica. 相似文献