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11.
土壤消毒主要用于土壤病虫草害防控。过去几十年,土壤主要采用化学药品熏蒸消毒,不合理使用容易造成环境污染。土壤蒸汽消毒、火焰消毒和热水浇灌等需要专门的仪器设备,且存在能耗较高、灭生性强、容易破坏土壤结构等缺点。目前,土壤日晒技术受到意大利、美国、以色列等70多个国家农业科学家的广泛关注,但在中国依然处于初级阶段。本文总结了国内外学者关于土壤日晒对农业病虫草害、土壤肥力、农作物产量等方面的影响与应用,分析了土壤日晒存在的局限性,并对土壤日晒在未来农业绿色防控上的应用前景进行了展望,以期为农产品无公害生产提供理论依据和实践参考。  相似文献   
12.
芒是小麦重要的穗部器官和形态特征,是小麦长期进化和适应环境的结果,对产量和抗旱性等具有重要影响。目前,对麦芒的遗传与发育还缺乏系统的研究,相关基因克隆或精细定位的研究尚未见报道。本试验利用短芒材料‘六柱头’与长芒材料‘石矮1号’构建的F2群体(SL-F2)对芒的遗传与发育进行了研究。细胞学观察表明,短芒主要是由细胞长度变短引起;遗传分析表明,‘六柱头’的短芒由显性单基因控制;借助Wheat660K SNP芯片的BSA分析和SL-F2群体的精细定位,确定‘六柱头’的芒长抑制基因是前人报道的B2位点,并将其定位到6B染色体4.84Mb的物理区间(471.28~476.12 Mb)内,该区段在中国春与矮抗58间具有良好的共线性。在B2定位区间共有61个基因,其中5个在中国春穗部特异表达,TraesCS6B02G264400在中国春和Azhurnaya幼穗表达差异显著。这些研究结果为B2基因的克隆、小麦芒形成机理的解析及育种中的应用奠定了基础。  相似文献   
13.
AIM: To investigate the effect of salvianolate on oxidative damage induced by hydrogen peroxide in human endothelial EA.hy926 cells.METHODS: EA.hy926 cells were cultured in vitro and divided into the following groups:control group, damage group, and anti-damage groups (salvianolate+damage groups). The cell viability was measured by CCK-8 assay. The migration ability of the EA.hy926 cells was detected by Transwell assay. The content of nitric oxide (NO) in the culture supernatant of the EA.hy926 cells was examined. The levels of vascular endothelial growth factor (VEGF) were detected by ELISA. The apoptosis,mitochondrial membrane potential and intracellular superoxide anion content of the EA.hy926 cells were analyzed by flow cytometry. The protein levels of caspase-3, cleaved caspase-3, Bcl-2, Bax, NF-κB and p53 were determined by Western blot. RESULTS: Compared with damage group, the viability of EA.hy926 cells pretreated with salvianolate at different concentrations was significantly increased (P<0.05). The apoptotic rate was significantly decreased (P<0.05). Savianolate enhanced the migration ability of the cells. The levels of VEGF, NO and mitochondrial transmembrane potential were increased (P<0.05), and the intracellular ROS level was significantly decreased (P<0.05). The protein levels of NF-κB, p53, Bax and cleaved caspase-3 were significantly decreased, and the protein level of Bcl-2 was markedly increased(P<0.05). CONCLUSION: Savianolate reduces the damage of EA.hy926 cells by hydrogen peroxide exposure, and its mechanism may be related to the blocking of NF-κB signaling pathway.  相似文献   
14.
海茄砧1 号是以野生茄子自交系HZ09-5 为母本,以从越南引进的茄子品种自交系HZ10-2 为父本育成的高抗青枯 病樱桃番茄砧木品种。植株生长势较强,第1 雌花节位约为第7 节,花为紫色,果实卵圆形,青熟果淡绿紫色或淡绿色,果 萼绿色,果长7~9 cm,果宽4~6 cm,单果质量为50~60 g,种子千粒重为3.2 g 左右,种皮浅黄色,高抗青枯病。海茄砧 1 号与樱桃番茄的嫁接亲和性好,共生性强,嫁接苗成活率高。嫁接后的樱桃番茄果萼开展,果面有光泽,可明显改善果实 VC、可溶性固形物和可滴定酸含量等品质,提高产量。适宜华南地区樱桃番茄的嫁接栽培。  相似文献   
15.
An agglutination test based on colored silica nanoparticles (colored SiNps) was established to detect serotypes of Pseudomonas aeruginosa. Monodisperse colored SiNps were used as agglutination test carriers. The colored SiNps were prepared through reverse microemulsion with reactive dyes, sensitized with 11 kinds of mono-specific antibodies against P. aeruginosa, and denoted as IgG-colored SiNps. Eleven kinds of IgG-colored SiNps were individually mixed with P. aeruginosa on a glass slide. Different serotypes of P. aeruginosa could be identified by agglutination test with evident agglutination. The P. aeruginosa could be detected in a range from 3.6 × 105 to 3.6 × 1012 cfu mL?1. This new agglutination test was confirmed to be a specific, sensitive, fast, easy-to-perform, and cost-efficient tool for the routine diagnosis of P. aeruginosa.  相似文献   
16.
红星302 是以抗病、耐低温弱光材料01-61 为母本,以01-23 为父本育成的串番茄一代杂种,无限生长类型,果实串收,果色亮红,果实椭圆形,酸甜适口,品质佳,VC 含量为364 mg · kg-1,可滴定酸0.44%,可溶性糖4.25%,平均单果质量30.79 g,硬度为11.40×105 Pa。单株结果数约为53个,产量4 900 kg ·( 667 m2-1 左右,高抗蕨叶病毒病、青枯病,适宜河北地区冬季日光温室和早春保护地栽培。  相似文献   
17.
AIM:To explore the effect of pidotimod on the renal function in IgA nephropathy (IgAN) rat model, and to further study whether this effect is related to the inhibition of inflammatory response. METHODS:The SD rats (n=36) were randomly divided into control group, IgAN model group, IgAN with prednisone treatment group and IgAN with pidotimod treatment group, with 9 rats in each group. The IgAN model was induced by consecutive oral administration of bovine gamma globulin (BGG) for 8 weeks followed by injection of BGG through tail vein for 3 d. After the IgAN model was established, the drug was continuously used for 4 weeks. At the end of the treatment, the urine protein, serum creatinine and blood urea nitrogen were examined by an automated analyzer. IgA deposition in the renal tissues was observed by immunofluorescence staining. The mRNA expression levels of renal fibrosis markers transforming growth factor-β1 (TGF-β1) and fibronectin 1 in the renal tissues were detected by RT-qPCR. The mRNA and protein levels of pro-inflammatory cytokines interleukin-1β (IL-1β) and IL-6 in the renal tissues were determined by RT-qPCR and Western blot, respectively. RESULTS:No significant difference of the body weight was observed in different groups. Compared with control group, the content of urine protein, serum creatinine and blood urea nitrogen were significantly increased (P<0.01), whereas those were reversed by pidotimod treatment. The results of immunofluorescence staining showed that pidotimod inhibited IgA deposition in the IgAN rats. Pitomod treatment inhibited the mRNA expression levels of renal fibrosis markers TGF-β1 and fibronectin 1, and the mRNA and protein levels of pro-inflammatory cytokines IL-1β and IL-6 in the renal tissues of IgAN rats. CONCLUSION:Pidotimod alleviates IgAN progression in rats by inhibition of inflammatory response.  相似文献   
18.
AIM: To investigate the effects of astragaloside IV (AS-IV) on chemokine receptor 4 (CXCR4) and stromal cell-derived factor 1α (SDF-1α) in endothelial progenitor cells (EPCs) and its mechanism. METHODS: Rat bone marrow-derived EPCs were cultured in vitro. The proliferation, adhesion, migration, apoptosis and tube formation capacity of EPCs treated with AS-IV and AMD3100, a specific blocker of CXCR4, were observed. The effects of AS-IV on the expression of SDF-1α/CXCR4 at mRNA and protein levels and the protein level of p-CXCR4 in the EPCs were determined. RESULTS: AS-IV significantly enhanced the proliferation, adhesion, migration and tube formation abilities of EPCs, reduced the apoptosis of EPCs, and up-regulated the mRNA and protein expression of SDF-1α and CXCR4 and the p-CXCR4 protein level in the EPCs. On the other hand, AMD3100 blocked the up-regulating effect of AS-IV on the mRNA and protein expression of CXCR4 and the p-CXCR4 protein level in the EPCs, but did not affect the effect of AS-IV on the expression of SDF-1α. CONCLUSION: AS-IV might enhance the biological function of EPCs by regulating the expression of SDF-1α/CXCR in EPCs.  相似文献   
19.
AIM: To explore the role of DNA methylation of microRNA-30a-5p(miR-30a-5p) promoter region in hepatic injury. METHODS: Four-week-old normal mice and cystathionine β-synthase (CBS) single gene knockout mice were used and divided into normal (CBS+/+, n=12) group and single gene knockout (CBS+/-, n=12) group, and the mice were fed with high methionine diet for 8 weeks. HL-7702 hepatic cells were routinely cultured in vitro and divided into control group, homocysteine (Hcy) group and Hcy+5-azacytidne (AZC) group. Serum Hcy, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured by automatic biochemical analyzer. The levels of ALT and AST in the cells culture medium were determined by the microplate method. Hepatic injury in the mice were observed with HE staining. Cell viability staining was used to measure the viability of hepatocytes. RT-qPCR was used to detect the expression of miR-30a-5p in the liver tissues and hepatocytes. The correlation between the expression of miR-30a-5p and serum ALT and AST levels was analyzed by Pearson correlation analysis. DNA methylation level of miR-30a-5p promoter region in the liver tissues and hepatocytes was detected by nested landing methylation-specific PCR (nMS-PCR). RESULTS: Compared with the CBS+/+ mice, the serum levels of Hcy, ALT and AST in the CBS+/- mice were significantly increased (P < 0.05). HE staining showed the hepatocyte swelling and nuclear fragmentation and dissolution. The expression level of miR-30a-5p in the liver tissues was decreased (P < 0.01). Besides, the expression level of miR-30a-5p in the mice was negatively correlated with serum ALT and AST levels (r2=0.4557, P=0.0003, r2=0.4626, P=0.0003), and the DNA methylation of miR-30a-5p promoter region was increased (P < 0.01). In the HL-7702 cells, compared with control group,the ALT and AST levels were increased in Hcy group (P < 0.05, P < 0.01), and the cell viability was remarkablely decreased. DNA methylation of miR-30a-5p promoter region was increased (P < 0.01), which decreased after treated the cells with AZC (P < 0.05), while the expression level of miR-30a-5p in the cells was increased (P < 0.05). CONCLUSION: Hypermethylation of miR-30a-5p promoter region may play an important role in hepatic injury.  相似文献   
20.
寿研梦扬是由母本CSVHPM1407001和父本CSVHPF1407002配制而成的羊角椒一代杂种。植株长势旺盛,连续坐果能力强;果实长羊角形,果长25~30 cm,果肩宽3~4 cm;青熟果黄绿色,老熟果红色;外表光亮,商品性好,耐贮运;单果质量100 g左右,辣味浓,宜鲜食;田间对病毒病、炭疽病和疫病的抗性强于对照喜洋洋。保护地栽培鲜椒产量可达12 840 kg·(667 m~2)~(-1)左右。适宜山东、河北等地区早春、秋延保护地种植。  相似文献   
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