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Salinity and Orobanche or Phelipanche spp. infection are important crop stress factors in agricultural areas. In this study, we investigated the effect of salt stress on Phelipanche ramosa seed germination and its attachment onto Arabidopsis thaliana roots. We also evaluated the effect of both stresses on the expression of genes regulated by abiotic and biotic stresses. According to our results, high concentration of NaCl delayed P. ramosa seed germination in the presence of a strigolactone analogue (GR24). A similar pattern was observed in the presence of A. thaliana plants. Furthermore, we found that salt‐treated A. thaliana seedlings were more sensitive to P. ramosa attachment compared with the untreated plants, indicating that there was a positive correlation between salt sensitivity and the ability of P. ramosa to infect A. thaliana plants. At the molecular level, a synergystic effect of both salt and P. ramosa stresses was observed on the cold‐regulated (COR) gene expression profile of treated A. thaliana seedlings. Our data clarify the interaction between parasitic plants and their hosts under abiotic stress conditions. 相似文献
76.
The normal embryonic development of organs and other tissues in mice and all species is preprogrammed by genes. Inactivation of a gene involved in any stage of normal embryonic development can have severe consequences leading to embryonic or postnatal developmental defects and lethality. Pathology methods are reviewed for evaluating normal and abnormal placenta and embryo, especially after E12.5. These methods include pathology protocols for necropsy and histopathology in addition to references that will provide additional knowledge for embryo assessment including histology atlases and advanced embryo imaging techniques. 相似文献
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In 1967, 1968 and 1969 the efficacy of aerial low volume and ultra-low volume bait-spraying against Dacus oleae (Gmel.) was compared in Greece. Results were mainly assessed by periodical trapping and by post-treatment countings of the percentage of attack in sampled olives. No difference between the effect of the two methods became apparent. It is deemed necessary, however, to repeat the experiments under conditions of heavier infestation. 相似文献
79.
A. Tempel J. Meltzer B. G. van den Bos 《European journal of plant pathology / European Foundation for Plant Pathology》1968,74(5):133-139
The compounds referred to in the title have been investigated for fungicidal, insecticidal and acaricidal activities in laboratory and greenhouse tests. Several representatives of this class of compounds were active against powdery mildew on apple, cucumber, and barley, and against aphids and spider mites, both when applied to the leaves and when added to the nutrient solutions of test plants. Treatment of leaf halves resulted in protection of the entire leaves. A striking difference in pesticidal activity was observed between two series of isomers. Representatives of the series with the phosphoryl group in the 1-position showed much greater pesticidal activities than their corresponding isomers with the phosphoryl group in the 2-position. The optimum activity within the two homologous series (R-H, CH3 ... C6H13) was determined: generally the lower homologues (R-H, CH3, C2H5 and i-C3H7) showed the greatest pesticidal activity in the systemic tests. After leaf-application the influence of the length of R was less pronounced or even reversed.Samenvatting De in de titel genoemde stoffen zijn onderzocht op fungicide, insecticide en acaricide werking in laboratorium en kasproeven. Verscheidene vertegenwoordigers van dit type verbindingen waren werkzaam tegen echte meeldauw van appel, komkommer en gerst, en tegen bladluizen en spint, dit zowel na toepassing op de bladeren als na toevoeging aan de voedingsoplossingen van proefplanten. Behandeling van bladhelften resulteerde in bescherming van de gehele bladeren. Een opvallend verschil werd waargenomen tussen de werking van twee reeksen isomeren. Vertegenwoordigers van de reeks met de fosforylgroep op de 1-plaats waren veel werkzamer dan hun isomeren met de fosforylgroep op de 2-plaats. Het optimum binnen de twee homologe reeksen (R-H, CH3 ... C6H13) werd bepaald: in het algemeen waren de lagere homologen (R-H, CH3; C2H5 en i-C3H7) het werkzaamst in de systemische proeven. Na een preventieve bladbespuiting was de invloed van de lengte van R minder uitgesproken of zelfs omgekeerd. 相似文献
80.
Circulating antibodies to larval Argas polonicus antigen detected in the blood of pigeons by means of ELISA reach their highest level 3-6 days post-tick attachment. During 6-8 days post infestation when most larvae detach from their host, there is an abrupt drop of the antibody level in blood followed by second peak at day 10-15. During the secondary and subsequent infestations the dynamics of the antibody production is analogous, but the maximum absorbance values found are higher with each following infestation. This is in direct correlation with the growth of immune resistance of hosts. The transfer of immunoglobulins of resistant pigeons produces in naive hosts a partial resistance in a statistically significant (P less than 0.01) reduction of the number of engorged larvae, in the shortening of larval feeding period and in the decrease of their mean weight after feeding. However this resistance was significantly (P less than 0.01) less expressed than in naturally resistant pigeons during secondary infestation. The protracted effect on the duration of premoulting period and the percentage of moulted larvae manifested in larvae after secondary infestation was not apparent in molecular weight of approximately 19, 21, 23, 27, 45 and 165 kilodaltons, were recognized by serum of resistant pigeons. 相似文献