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991.
Phosphorus unavailability and lack of organic matter in calcareous soils under semiarid climates are the major reasons for low crop productivity. A field experiment was conducted at The Agronomy Research Farm of The University of Agriculture Peshawar (semiarid climate), during summer 2015. The objective of the research was to investigate the effect of plant residues, organic and inorganic phosphorus management on improving yield and yield components of hybrid maize (CS-200) with (+) and without (?) phosphate solubilizing bacteria. The experiment was laid out in randomized complete block design with split plot arrangement, using three replications. A combination of plant residues and phosphorus sources were used as mainplot factor, and phosphate solubilizing bacteria were used as a subplot factor. The results revealed that plant residues, phosphorus sources and phosphate solubilizing bacteria significantly affected all parameters under study except number of plants at harvest. Application of legume residues (Faba bean) increased ear length (22.9 cm), grains row?1 (46) and ear?1 (419), 1000 grains weight (365 g), grain yield (6175 kg ha?1) and shelling percentage (83) as compared to paper mulberry and garlic residues. Phosphorus application at the higher rate of 120 kg ha?1 from inorganic source (single super phosphate) was superior in terms of higher ear length (24.4 cm), number of grains row?1 (48) and ear?1 (455), 1000 grains weight (380 g), grain yield (6558 kg ha?1), harvest index (42.7%) and shelling percentage (83%) than the lower rate of phosphorus (60 kg P ha?1). Inoculation of maize seeds with beneficial microbes (phosphate solubilizing bacteria) significantly increased ear length (22.9 cm), number of grains row?1 (45) and ear?1 (413), 1000 grains weight (364 g), grain yield (6237 kg ha?1), harvest index (41.8%) and shelling percentage (82) than without seed inoculation. On the basis of our results from this study, we concluded that application of faba bean residues, 120 kg P ha?1 as single super phosphate along with seed inoculation with phosphate solubilizing bacteria could improve yield and yield components of hybrid maize under semiarid climates.  相似文献   
992.
Aquaporin-4 (AQP4) is a water channel protein that is predominantly expressed in astrocytes in the CNS. The rapid water flux through AQP4 may contribute to electrolyte/water homeostasis and may support neuronal activities in the CNS. On the other hand, little is known about the expression of AQP4 in the peripheral nervous system (PNS). Using AQP4−/− mice as a negative control, we demonstrated that AQP4 is also expressed in sensory ganglia, such as trigeminal ganglia and dorsal root ganglia in the PNS. Immunohistochemistry revealed that AQP4 is exclusively localized to satellite glial cells (SGCs) surrounding the cell bodies of the primary afferent sensory neurons in the sensory ganglia. Biochemical analyses revealed that the expression levels of AQP4 in sensory ganglia were considerably lower than those in astrocytes in the CNS. Consistently, behavioral analyses did not show any significant difference in terms of mechanical and cold sensitivity between wild type and AQP4−/− mice. Overall, although the pathophysiological relevance of AQP4 in somatosensory perception remains unclear, our findings provide new insight into the involvement of water homeostasis in the peripheral sensory system.  相似文献   
993.
994.
新疆艾比湖湿地博乐河入口处土壤细菌多样性分析   总被引:1,自引:0,他引:1  
【目的】了解新疆艾比湖湿地国家级自然保护区非培养土壤细菌群落组成及多样性。【方法】采用非培养法直接从湿地土壤提取总DNA进行16S r RNA基因扩增,构建细菌16S r RNA基因克隆文库。使用MspⅠ和AfaⅠ限制性内切酶对阳性克隆进行16S r RNA基因扩增片段的限制性酶切分析(Amplified r DNA restriction analysis,ARDRA),挑取具有不同双酶切图谱的克隆进行测序,序列比对并构建16S r RNA基因系统发育树。【结果】从土壤细菌的16S r RNA基因文库中随机挑取75个不同谱型的克隆子,共得到58个OTUs,系统发育归类为8个细菌类群:绿弯菌门(Chloroflexi)、蓝藻门(Cyanobacteria)、变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、放线菌门(Actinobacteria)、拟杆菌门(Bacteroidetes)、疣微菌门(Verrucomicrob)和芽单胞菌门(Gemmatimonadetes)。其中,变形菌门为第一优势菌群,拟杆菌门为第二优势菌群,两者约占总克隆的65%。【结论】艾比湖湿地博乐河入口处土壤细菌多样性丰富,且存在一定数量的潜在微生物新种。  相似文献   
995.
Abscisic acid (ABA) is a ubiquitous hormone that regulates plant growth, development and responses to environmental stresses. In recent researches, pyrabactin resistance 1-like protein (PYL) and protein phosphatase type 2C (PP2C) were identified as the direct receptor and the second component of ABA signaling pathway, respectively. However, a lot of PYL and PP2C members were found in Arabidopsis and several other plants. Some of them were found not to be involved in ABA signaling. Because of the complex diversity of the genome, few documents have been available on the molecular details of the ABA signal perception system in maize. In the present study, we conducted bioinformatics analysis to find out the candidates (ZmPYL3 and ZmPP2C16) of the PYL and PP2C members most probably involved in ABA signaling in maize, cloned their encoding genes (ZmPYL3 and ZmPP2C16), verified the interaction between these two proteins in response to exogenous ABA induction by yeast two-hybrid assay and bimolecular fluorescence complementation, and investigated the expression patterns of these two genes under the induction of exogenous ABA by real-time fluorescence quantitative PCR. The results indicated that the ZmPYL3 and ZmPP2C16 proteins interacted in vitro and in vivo in response to the induction of exogenous ABA. The downregulated expression of the ZmPYL3 gene and the upregulated expression of the ZmPP2C16 gene are responsive to the induction of exogenous ABA. The ZmPYL3 and ZmPP2C16 proteins are the most probable members of the receptors and the second components of ABA signaling pathway, respectively.  相似文献   
996.
997.
Ramie fiber extracted from stem bark is one of the most important natural fibers. The root-lesion nematode (RLN) Pratylenchus coffeae is a major ramie pest and causes large fiber yield losses in China annually. The response mechanism of ramie to RLN infection is poorly understood. In this study, we identified genes that are potentially involved in the RLN-resistance in ramie using Illumina pair-end sequencing in two RLN-infected plants (Inf1 and Inf2) and two control plants (CO1 and CO2). Approximately 56.3, 51.7, 43.4, and 45.0 million sequencing reads were generated from the libraries of CO1, CO2, Inf1, and Inf2, respectively. De novo assembly for these 196 million reads yielded 50,486 unigenes with an average length of 853.3 bp. A total of 24,820 (49.2%) genes were annotated for their function. Comparison of gene expression levels between CO and Inf ramie revealed 777 differentially expressed genes (DEGs). The expression levels of 12 DEGs were further confirmed by real-time quantitative PCR (qRT-PCR). Pathway enrichment analysis showed that three pathways (phenylalanine metabolism, carotenoid biosynthesis, and phenylpropanoid biosynthesis) were strongly influenced by RLN infection. A series of candidate genes and pathways that may contribute to the defense response against RLN in ramie will be helpful for further improving resistance to RLN infection.  相似文献   
998.
Complement factor H (CFH) is an essential regulator of the complement system and plays very important roles in animal innate immunity. Although the complement system of amphioxus has been extensively studied, the expression in amphioxus and evolution of CFH gene remain unknown. In this study, we identified and characterized an amphioxus (Branchiostoma belcheri) CFH gene (designated as AmphiCFH). Our results showed that the full-length cDNA of AmphiCFH gene consists of 1295 bp nucleotides containing an 855 bp open reading frame (ORF) that was predicted to encode a 284 amino acid protein. The putative AmphiCFH protein possessed the characteristic of the CFH protein family, including typical CCP (complement control protein) domain. Real-time PCR analysis showed that the AmphiCFH was ubiquitously and differentially expressed in five investigated tissues (intestine, gills, notochord, muscles, and hepatic cecum). The expression level of the AmphiCFH gene was induced upon lipopolysaccharide stimulation, indicating that the AmphiCFH gene might be involved in innate immunity. In addition, phylogenetic analysis showed that the AmphiCFH gene was located between that of invertebrates and vertebrates, suggesting that the AmphiCFH gene is a member of the CFH gene family. In conclusion, our findings provided an insight into animal innate immunity and evolution of the CFH gene family.  相似文献   
999.
我国大陆一新入侵种:七角星蜡蚧(半翅目:蚧总科:蚧科)   总被引:1,自引:1,他引:0  
七角星蜡蚧Ceroplastes stellifera(Westwood)是一种多食、热带广布害虫,2007年被列入《中华人民共和国进境植物检疫性有害生物名录》中。该虫在我国以前仅记录于台湾省,2013年10月下旬,发现该虫在云南省西双版纳地区危害鹅掌柴(Schefflera octophylla)和芒果(Mangifera indica),为我国大陆的新入侵害虫。本文介绍了其形态特征、地理分布、寄主植物、经济重要性等。  相似文献   
1000.
An almost complete skeleton with partial cranial material (ZMNH-M8739) is recovered from the Early or Middle Jurassic of southwest China. ZMNH-M8739 is identified as a juvenile individual of basal sauropodomorph dinosaur, Yunnanosaurus robustus Young, 1951. The revised diagnoses are as follows: absence of anteroposterior expansion on the medial end of astragalus and dorsoventrally compressed medium shaft of the metatarsal IV. Unfused neural arch and finely grooved long bone surface texture indicate that this individual is in the immature growth stage. ZMNH-M8739 possesses the tooth–tooth wear facet on its mesial maxillary and dentary teeth. However, the distal maxillary teeth have coarse serrations. Such a characteristic dentition could represent a unique feeding mechanism of this animal. Finally, ZMNH-M8739 constitutes a monophyletic group with Y. robustus (holotype), and Y. huangi is nesting this clade in the phylogenetic tree of the present analysis. Comparison of juvenile and adult specimen reveals distinctive growth changes of Y. robustus. This clade is positioned in an unnamed clade at a sister taxon of Sauropoda. Finally, some members of the so-called prosauropod dinosaurs constitute a monophyletic group in the present result.  相似文献   
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