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101.
Skorpil P Saad MM Boukli NM Kobayashi H Ares-Orpel F Broughton WJ Deakin WJ 《Molecular microbiology》2005,57(5):1304-1317
Rhizobium sp. NGR234 nodulates many plants, some of which react to proteins secreted via a type three secretion system (T3SS) in a positive- (Flemingia congesta, Tephrosia vogelii) or negative- (Crotalaria juncea, Pachyrhizus tuberosus) manner. T3SSs are devices that Gram-negative bacteria use to inject effector proteins into the cytoplasm of eukaryotic cells. The only two rhizobial T3SS effector proteins characterized to date are NopL and NopP of NGR234. NopL can be phosphorylated by plant kinases and we show this to be true for NopP as well. Mutation of nopP leads to a dramatic reduction in nodule numbers on F. congesta and T. vogelii. Concomitant mutation of nopL and nopP further diminishes nodulation capacity to levels that, on T. vogelii, are lower than those produced by the T3SS null mutant NGR(Omega)rhcN. We also show that the T3SS of NGR234 secretes at least one additional effector, which remains to be identified. In other words, NGR234 secretes a cocktail of effectors, some of which have positive effects on nodulation of certain plants while others are perceived negatively and block nodulation. NopL and NopP are two components of this mix that extend the ability of NGR234 to nodulate certain legumes. 相似文献
102.
Andrea Novelletto Mohammad Hafez Ann Di Rienzo Luciano Felicetti Giancarlo Deidda Zacharias El Morsi Youssef Al-Tonbary Magdi El-Ziny Nawal Abd-El-Gelil Luciano Terrenato 《Human genetics》1989,81(3):211-213
Summary The frequency of deletional -thalassemia in the Egyptian population was estimated at 0.08 by DNA analysis of a newborn random sample. No 0 determinants were found. The most frequent + determinant was the –3.7 type I in association with the medium allele at inter-zeta HVR. The –4.2 and anti 3.7 arrangements were found at very low frequencies. 相似文献
103.
Muhammad Zafar Siraj Ahmed Muhammad Kashif Munir Nawal Zafar Muhammad Saqib Muhammad Aleem Sarwar Saba Iqbal Baber Ali Naveed Akhtar Basharat Ali Sadam Hussain Muhammad Saeed Mohammad Khalid Al-Sadoon Aneela Gulnaz 《Phyton》2023,92(4):983-999
Deficiencies of essential vitamins, iron (Fe), and zinc (Zn) affect over one-half of the world’s population. A significant progress has been made to control micronutrient deficiencies through supplementation, but new approaches are needed, especially to reach the rural poor. Agronomic biofortification of pulses with Zn, Fe, and boron (B) offers a pragmatic solution to combat hidden hunger instead of food fortification and supplementation. Moreover, it also has positive effects on crop production as well. Therefore, we conducted three separate field experiments for two consecutive years to evaluate the impact of soil and foliar application of the aforementioned nutrients on the yield and seed biofortification of mungbean. Soil application of Zn at 0, 4.125, 8.25, Fe at 0, 2.5, 5.0 and B at 0, 0.55, 1.1 kg ha−1 was done in the first, second and third experiment, respectively. Foliar application in these experiments was done at 0.3% Zn, 0.2% Fe and 0.1% B respectively one week after flowering initiation. Data revealed that soil-applied Zn, Fe and B at 8.25, 5.0 and 1.1 kg ha−1, respectively, enhanced the grain yield of mungbean; however, this increase in yield was statistically similar to that recorded with Zn, Fe and B at 4.125, 2.5 and 0.55 kg ha−1, respectively. Foliar application of these nutrients at flower initiation significantly enhanced the Zn contents by 28% and 31%, Fe contents by 80% and 78%, while B contents by 98% and 116% over control during 2019 and 2020, respectively. It was concluded from the results that soil application of Zn, Fe, and B enhanced the yield performance of mungbean; while significant improvements in seed Zn, Fe, and B contents were recorded with foliar application of these nutrients. 相似文献
104.
The effect of constant 26, 30, 34, and 37 C temperatures on diapause incidence (percentage of diapause females) and intensity (duration of preoviposition period) was compared in field-collected (FC) and laboratory-reared (LR) F1 and F2 female A. (P.) arboreus. Diapause incidence, 89–100%, and intensity 115–133 days, in the FC were high at all temperatures except at 30 C when the intensity was reduced (84 days). Diapause incidence, 91–94%, and intensity, 132–137 days, in LRF1 were high at 26 and 30 C. At 34 and 37 C, both (33% and 78 days) were lower than in FC and LRF1 at 26 and 30 C. Diapause incidence was always lower in LRF2 than in FC and LRF1 and decreased as the temperature increased (58, 30, 17, and 0%, respectively). Diapause intensity in LRF2 at 26 C (133 days) was high and similar to that in FC and LRF1 at 26 C but was low at 30 and 34 C (84 and 87 days, respectively). In all groups, diapause intensity was higher in females kept outdoors (191–218 days) than in those held in the laboratory. The results suggest that rearing in the laboratory caused an increased sensitivity of diapause LRF1 and F2 females to high temperature. 相似文献
105.
106.
Singh Swati Singh Vijay Pratap Prasad Sheo Mohan Sharma Shivesh Ramawat Naleeni Dubey Nawal Kishore Tripathi Durgesh Kumar Chauhan Devendra Kumar 《Journal of Plant Growth Regulation》2019,38(4):1587-1597
Journal of Plant Growth Regulation - The present study has been conducted to evaluate the impact of silicon (Si) and salicylic acid (SA) in the regulation of Cd-induced toxicity in maize seedlings.... 相似文献
107.
Effects of contemporary environment and Quaternary climate change on drylands plant diversity differ between growth forms 总被引:1,自引:0,他引:1
Yunpeng Liu Xiangyan Su Nawal Shrestha Xiaoting Xu Siyang Wang Yaoqi Li Qinggang Wang Denis Sandanov Zhiheng Wang 《Ecography》2019,42(2):334-345
Previous studies on large‐scale patterns in plant richness and underlying mechanisms have mostly focused on forests and mountains, while drylands covering most of the world's grasslands and deserts are more poorly investigated for lack of data. Here, we aim to 1) evaluate the plant richness patterns in Inner Asian drylands; 2) compare the relative importance of contemporary environment, historical climate, vegetation changes, and mid‐domain effect (MDE); and 3) explore whether the dominant drivers of species richness differ across growth forms (woody vs herbaceous) and range sizes (common vs rare). Distribution data and growth forms of 13 248 seed plants were compiled from literature and species range sizes were estimated. Generalized linear models and hierarchical partitioning were used to evaluate the relative contribution of different factors. We found that habitat heterogeneity strongly affected both woody and herbaceous species. Precipitation, climate change since the mid‐Holocene and climate seasonality dominated herbaceous richness patterns, while climate change since the Last Glacial Maximum dominated woody richness patterns. Rare species richness was strongly correlated with precipitation, habitat heterogeneity and historical climatic changes, while common species richness was strongly correlated with MDE (woody) or climate seasonality (herbaceous). Temperature had little effects on the species richness patterns of all groups. This study represents the first evaluation of the large‐scale patterns of plant species richness in the Inner Asian drylands. Our results suggest that increasing water deficit due to anthropogenic activities combined with future global warming may increase the extinction risk of many grassland species. Rare species (both herbaceous and woody) may face severe challenges in the future due to increased habitat destruction caused by urbanization and resource exploitation. Overall, our findings indicate that the hypotheses on species richness patterns based on woody plants alone can be insufficient to explain the richness patterns of herbaceous species. 相似文献
108.
Design, synthesis, and docking studies of new 1,3,4-thiadiazole-2-thione derivatives with carbonic anhydrase inhibitory activity 总被引:1,自引:0,他引:1
Abdel-Hamid MK Abdel-Hafez AA El-Koussi NA Mahfouz NM Innocenti A Supuran CT 《Bioorganic & medicinal chemistry》2007,15(22):6975-6984
A new series of 1,3,4-thiadiazole-2-thione derivatives have been prepared and assayed for the inhibition of three physiologically relevant carbonic anhydrase (CA, EC 4.2.1.1) isozymes, the cytosolic human isozymes I and II, and the transmembrane, tumor-associated hCA IX. Against hCA I the investigated thiones, showed inhibition constants in the range of 2.55-222 microM, against hCA II in the range of 2.0-433 microM, and against hCA IX in the range of 1.25-148 microM. Compound 5c, 4-(4,5-dihydro-5-thioxo-1,3,4-thiadiazol-2-yl)-1-(5-nitro-2-oxoindolin-3-ylidene)semicarbazide showed interesting inhibition of the tumor-associated hCA IX with K(I) value of 1.25 microM, being the first non-sulfonamide type inhibitor of such activity. This result is rather important taking into consideration the known antitumor activity of thiones. In addition, docking of the tested compounds into CA II active site was performed in order to predict the affinity and orientation of these compounds at the isozyme active site. The results showed similar orientation of the target compounds at CA II active site compared with reported sulfonamide type CAIs with the thione group acting as a zinc-binding moiety. 相似文献
109.
Zhiheng Wang Yaoqi Li Xiangyan Su Shengli Tao Xiao Feng Qinggang Wang Xiaoting Xu Yunpeng Liu Sean T. Michaletz Nawal Shrestha Markku Larjavaara Brian J. Enquist 《Journal of Plant Ecology》2019,12(5):791
Aims
Plant height is a key functional trait related to aboveground biomass, leaf photosynthesis and plant fitness. However, large-scale geographical patterns in community-average plant height (CAPH) of woody species and drivers of these patterns across different life forms remain hotly debated. Moreover, whether CAPH could be used as a predictor of ecosystem primary productivity is unknown. 相似文献
110.
Lian Liu Xiaoting Xu Lei Zhang Yaoqi Li Nawal Shrestha Danilo M. Neves Qinggang Wang Hong Chang Xiangyan Su Yunpeng Liu Jianyong Wu Dimitar Dimitrov Zhiheng Wang Jianquan Liu 《Journal of Plant Ecology》2022,15(2):237
北半球高山和极地虎耳草属物种丰富度的地理格局:温度和生境异质性的作用
现代气候、生境异质性和长期气候变化对森林生态系统中分布的木本植物的物种丰富度格局的影响在以往研究中受到广泛关注,但对高寒-极地生态系统中的草本植物物种丰富度格局及其影响因素的研究仍较少。本研究旨在检验以往研究中基于物种丰富度和环境因子关系提出的假说是否能够解释高寒-极地地区典型草本植物-虎耳草属(Saxifraga)的物种丰富度格局。本研究利用全球437种虎耳草属物种分布数据,探讨了全部物种、广域和狭域物种丰富度格局的影响因素。采用广义线性模型和空间自回归模型,评估了现代气候、生境异质性和历史气候对虎耳草属物种丰富度格局的影响。采用偏回归分析了不同变量对物种丰富度的独立解释率和共同解释率,并检验了4种广泛使用的物种丰富度与环境关系模型对物种丰富度格局的解释能力。研究结果表明,温度与虎耳草属所有物种和广域物种的物种丰富度格局呈显著负相关关系,是影响物种丰富度格局最重要的环境因子,这可能反映了虎耳草属对其祖先温带生态位的保守性。生境异质性和末次冰期以来的气候变化是虎耳草属狭域物种丰富度空间变异的最佳预测因子。总体而言,包含5个预测变量的组合模型可以解释大约40%–50%的虎耳草属物种丰富度的空间变异。此外,进化和生物地理过程在虎耳草属物种丰富度格局形成方面可能发挥了重要作用,这有待进一步研究。 相似文献