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161.
DARJA STANI RACMAN KARA MCGEACHY BRIAN REAVY BORUT TRUKELJ JANA EL HUGH BARKER 《The Annals of applied biology》2001,139(2):269-275
The potato cv. Igor is susceptible to infection with Potato virus Y (PVY) and in Slovenia it has been so severely affected with NTN isolates of PVY causing potato tuber necrotic ringspot disease (PTNRD) that its cultivation has ceased. Plants of cv. Igor were transformed with two transgenes that contained coat protein gene sequence of PVYNTN. Both transgenes used PVY sequence in a sense (+) orientation, one in native translational context (N‐CP), and one with a frame‐shift mutation (FS‐CP). Although most transgenic lines were susceptible to infection with PVYNTN and PVYO, several lines showed resistance that could be classified into two types. Following manual or graft inoculation, plants of partially resistant lines developed some symptoms in foliage and tubers, and virus titre in the foliage, estimated by ELISA, was low or undetectable. In highly resistant (R) lines, symptoms did not develop in foliage and on tubers, and virus could not be detected in foliage by ELISA or infectivity assay. Four lines from 34 tested (two N‐CP and two FS‐CP) were R to PVYNTN and PVYO and one additional line was R to PVYO. When cv. Spey was transformed with the same constructs, they did not confer strong resistance to PVYO. 相似文献
162.
163.
Mohammad Rafiqul Islam Mohd Mostofa Kamal Mohammad Faruk Hossain Jamil Hossain Mohammad Golam Azam Mst Masuma Akhter M. Kamrul Hasan Ibrahim Al-Ashkar Khalid F. Almutairi Ayman EL Sabagh Md Atikur Rahman Muhammad Aamir Iqbal Mohammad Sohidul Islam 《Phyton》2023,92(3):955-981
Drought is one of the critical conditions for the growth and productivity of many crops including mung bean
(Vigna radiata L. Wilczek). Screening of genotypes for variations is one of the suitable strategies for evaluating
crop adaptability and global food security. In this context, the study investigated the physiological and biochemical responses of four drought tolerant (BARI Mung-8, BMX-08010-2, BMX-010015, BMX-08009-7), and four
drought sensitive (BARI Mung-1, BARI Mung-3, BU Mung-4, BMX-05001) mung bean genotypes under wellwatered (WW) and water deficit (WD) conditions. The WW treatment maintained sufficient soil moisture
(22% ± 0.5%, i.e., 30% deficit of available water) by regularly supplying water. Whereas, the WD treatment
was maintained throughout the growing period, and water was applied when the wilting symptom appeared.
The drought tolerant (DT) genotypes BARI Mung-8, BMX-08010-2, BMX-010015, BMX-08009-7 showed a high
level of proline accumulation (2.52–5.99 mg g−1 FW), photosynthetic pigment (total chlorophyll 2.96–3.27 mg g−1
FW at flowering stage, and 1.62–2.38 mg g−1 FW at pod developing stage), plant water relation attributes including relative water content (RWC) (82%–84%), water retention capacity (WRC) (12–14) as well as lower water
saturation deficit (WSD) (19%–23%), and water uptake capacity (WUC) (2.58–2.89) under WD condition, which
provided consequently higher relative seed yield. These indicate that the tolerant genotypes gained better physiobiochemical attributes and adaptability in response to drought conditions. Furthermore, the genotype BMX-
08010-2 showed superiority in terms of those physio-biochemical traits, susceptibility index (SSI) and stress tolerance index (STI) to other genotypes. Based on the physiological and biochemical responses, the BMX-08010-2 was
found to be a suitable genotype for sustaining yield under drought stress, and subsequently, it could be recommended
for crop improvement through hybridization programs. In addition, the identified traits can be used as markers to
identify tolerant genotypes for drought-prone areas. 相似文献
164.
165.
Iron requirement and siderophore production in Rhizobium ciceri during growth on an iron-deficient medium 总被引:1,自引:0,他引:1
Berraho EL. Lesueur D. Diem H.G. Sasson A. 《World journal of microbiology & biotechnology》1997,13(5):501-510
Under conditions of iron limitation many rhizospheric bacteria produce siderophores, ferric iron-specific ligands, which may enhance plant growth by increasing the availability of iron near the roots. Thirty-five strains of Rhizobium ciceri, specific to chickpea (Cicer arietinum L.), were screened for their ability to grow on iron-deficient medium and to produce siderophores. Maximal growth of all strains previously depleted in iron was obtained in medium containing 5 to 10 m of ferric iron. When iron limitation was achieved by the addition of 2,2-bipyridyl or EDDHA [ethylene diamine di(o-hydroxyphenyl) acetic acid] to the medium, only two strains were able to scavenge iron and grow. Siderophore production by these two strains was detected by the Chrome Azurol S assay (CAS), a universal test for siderophores. No hydroxamate-type siderophores were detected in the supernatants of Rhizobium ciceri cultures. However, some strains secreted salicylic acid and 2,3-dihydroxybenzoic acid as phenolate-type siderophores. Addition of ferric iron to the culture medium increased growth yield significantly but depressed the production of siderophores. Although these compounds are produced in response to iron deficiency, nutritive components of the culture medium significantly affected their production. It seems that CuII, MoVI and MnII ions bound competitively with iron to siderophores, resulting in a 34 to 100% increase in production. 相似文献
166.
Choline acetyltransferase activity of spinal cord cell cultures increased by co-culture with muscle and by muscle-conditioned medium 总被引:9,自引:3,他引:6
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Activity of the enzyme choline acetyltransferase (CAT), which mediates the synthesis of the neurotransmitter, acetylcholine, was increased up to 20- fold in spinal cord (SC) cells grown in culture with muscle cells for 2 wk. This increase was directly related to the duration of co-culture as well as to the cell density of both the SC and muscle involved and was not affected by the presence of the acetylcholine receptor blocking agent, α-bungarotoxin. Glutamic acid decarboxylase (GAD) activity was often markedly decreased in SC-muscle cultures while the activities of acetylcholinesterase and several other enzymes were little changed. Increased CAT activity was also observed when SC cultures were maintained in medium which had been conditioned by muscle cells or by undifferentiated cells from embryonic muscle. Muscle-conditioned medium (CM) did not affect the activities of SC cell GAD or acetylcholinesterase. Dilution or concentration of the CM directly affected its ability to increase SC CAT activity , as did the duration and timing of exposure of the SC cells to the CM. The medium could be conditioned by muscle cells in the presence or absence of serum, and remained effective after dialysis or heating to 58 degrees C. Membrane filtration data were consistent with the conclusion that the active material(s) in CM had a molecular weight in excess of 50,000 daltons. We conclude that large molecular weight material that is released by muscle cells is capable of producing a specific increase in CAT activity of SC cells. 相似文献
167.
Previously it was shown that stimulation of the P2Y12 receptor activates PKB signalling in C6 glioma cells [K. Van Kolen and H. Slegers, J. Neurochem. 89, 442.]. In the present study, the mechanisms involved in this response were further elucidated. In cells transfected with the Gbetagamma-scavenger beta-ARK1/GRK2 or Rap1GAPII, stimulation with 2MeSADP failed to enhance PKB phosphorylation demonstrating that the signalling proceeds through Gbetagamma-subunits and Rap1. Moreover, Rap1-GTP pull-down assays revealed that P2Y12 receptor stimulation induced a rapid activation of Rap1. Treatment of cells with the Ca2+ chelator BAPTA-AM and inhibition of Src and PLD2 with PP2 or 1-butanol, respectively, abrogated P2Y12 receptor-mediated activation of Rap1 and PKB. In addition inhibition of PKCzeta decreased basal and 2MeSADP-stimulated phosphorylation of PKB indicating a role for this PKC isoform in PKB signalling. Although the increased PKB phosphorylation was abolished in the presence of the IGF-I receptor tyrosine kinase inhibitor AG 1024, 2MeSADP did not significantly increase receptor phosphorylation. Nevertheless, phosphorylation of a 120 kDa IGF-I receptor-associated protein was observed. The latter protein was identified by MALDI-TOF/TOF-MS as the proline-rich tyrosine kinase 2 (Pyk2) that co-operates with Src in a PLD2-dependent manner. Consistent with the signalling towards Rap1 and PKB, activation of Pyk2 was abrogated by Ca2+ chelation, inhibition of PLD2 and IGF-I receptor tyrosine kinase activity. In conclusion, the data reveal a novel type of cross-talk between P2Y12 and IGF-I receptors that proceeds through Gbetagamma-, Ca2+-and PLD2-dependent activation of the Pyk2/Src pathway resulting in GTP-loading of Rap1 required for an increased PKB phosphorylation. 相似文献
168.
169.
The regional malaria epidemics of the early 1900s provided the basis for much of our current understanding of malaria epidemiology. Colonel Gill, an eminent malariologist of that time, suggested that the explosive nature of the regional epidemics was due to a sudden increased infectiousness of the adult population. His pertinent observations underlying this suggestion have, however, gone unheeded. Here, the literature on Plasmodium seasonal behaviour is reviewed and three historical data sets, concerning seasonal transmission of Plasmodium falciparum, are examined. It is proposed that the dramatic seasonal increase in the density of uninfected mosquito bites results in an increased infectiousness of the human reservoir of infection and, therefore, plays a key role in "kick-starting" malaria parasite transmission. 相似文献
170.
Espagne E Lespinet O Malagnac F Da Silva C Jaillon O Porcel BM Couloux A Aury JM Ségurens B Poulain J Anthouard V Grossetete S Khalili H Coppin E Déquard-Chablat M Picard M Contamine V Arnaise S Bourdais A Berteaux-Lecellier V Gautheret D de Vries RP Battaglia E Coutinho PM Danchin EG Henrissat B Khoury RE Sainsard-Chanet A Boivin A Pinan-Lucarré B Sellem CH Debuchy R Wincker P Weissenbach J Silar P 《Genome biology》2008,9(5):R77-22