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661.
Xiaosha Li Huifang Han Tangyuan Ning Ying Shen Rattal Lal 《Soil Use and Management》2019,35(4):585-594
To assess changes in organic carbon pools, an incubation experiment was conducted under different temperatures and field moisture capacity (FMC) on a brown loam soil from three tillage practices used for 12 years: no‐till (NT), subsoiling (ST) and conventional tillage (CT). Total microbial respiration was measured for incubated soil with and without the input of straw. Results indicated that soil organic carbon (SOC) and microbial biomass carbon (MBC) under ST, NT and CT was higher in soil with straw input than that without, while the microbial quotient (MQ or MBC: SOC) and metabolic quotient (qCO2) content under CT followed the opposite trend. Lower temperature, lower moisture and with straw input contributed to the increases in SOC concentration, especially under NT and ST systems. The SOC concentrations under ST, with temperatures of 30 and 35°C after incubation at 55% FMC, were greater than those under CT by 28.4% and 30.6%, respectively. The increase in MBC was highest at 35°C for 55%, 65% and 75% FMC; in soil under ST, MBC was greater than that under CT by 199.3%, 50.7% and 23.8%, respectively. At 30°C, the lower qCO2 was obtained in soil incubated under NT and ST. The highest MQ among three tillage practices was measured under ST at 55% FMC, NT at 65% FMC and CT at 75% FMC with straw input. These data indicate the benefits of enhancing the MQ; the low FMC was beneficial to ST treatment. Under higher temperature and drought stress conditions, the adaptive capacity of ST and NT is better than that of CT. 相似文献
662.
Xinliang Dong Bhupinder Pal Singh Guitong Li Qimei Lin Xiaorong Zhao 《Soil Use and Management》2019,35(3):466-477
Biochar application can improve soil properties, such as increasing soil organic carbon content, soil pH and water content. These properties are important to soil dissolved organic carbon (DOC); however, the effects of biochar on DOC concentration and composition have received little research attention, especially several years after biochar application under field conditions. This study was conducted in a long‐term experimental field where the biochar was only applied once in 2009. The purpose of the study was to investigate the effect of different biochar application rates (0, 30, 60 and 90 t ha?1) on the dynamics of soil water content, DOC concentration and DOC compositions (reducing sugar, soluble phenol and aromatics) over nine samplings during a 12‐month period in 2014. Our results showed that soil water content and DOC concentration varied from 7.1% to 14.5% and 59 to 230 mg C kg?1 soil during the 12 months, respectively. However, the biochar application rates did not significantly (p > 0.05) affect soil water content, DOC concentration and DOC composition at the same sampling period. The DOC concentration across the biochar treatments was positively correlated to soil water content. Moreover, the DOC composition (reducing sugar, soluble phenol or aromatics) and their concentrations were positively correlated to the total DOC concentration. In addition, biochar did not affect soil bulk density, pH, saturated hydraulic conductivity and crop yields. The results indicated that some benefits of biochar to soil may not persist 5 years after the application of biochar under a field condition. 相似文献
663.
664.
Characterization of Genomic Integration and Transgene Organization in Six Transgenic Rapeseed Events
To characterize the DNA rearrangement of both the T-DNA region and the genomic insertion site during T-DNA insertion, the Genomewalker strategy was used to isolate the junctions between the inserted DNA and the plant genomic DNA in six rapeseed events as well as the genomic DNA at the sites before integration. During transformation in each of the six events, portions of both the right border(RB) and left border(LB) regions of the T-DNA were deleted, ranging from a 7 nucleotide deletion of the LB repeats in event RF1 to a 207 bp deletion of the LB region in event RF2. For the six events, T-DNA integration resulted in a deletion at the target site spanning less than 100 bp. Sequence analysis indicated that the T-DNA was integrated into the coding region of various native rapeseed genes in events RF1 and RF2. Duplications of the genomic DNA target site were observed in events RF2, RF3 and Topas 19/2. And multimerization of transgenes was found in event Topas 19/2, in which, the T-DNA was integrated as a head-to-head(RB-to-RB) concatemer into the recipient genome. In event MS1, chromosomal translocation or a large target-site deletion may have occurred during T-DNA integration, which was identified due to a failure to amplify the presumptive insertion site based on the flanking rapeseed DNA sequences. Our results provide comprehensive data concerning transgene organization and the genomic context of the T-DNA in six rapeseed events, which can aid in the developing of insert fingerprinting and the monitoring of long-term genetic stability and potential unintended effects of transgenic events. 相似文献
665.
666.
内蒙古膜下滴灌棉花叶面肥施用效果 总被引:1,自引:0,他引:1
以中棉所50和天元1号为材料,以喷施清水为对照,通过田间试验研究了从蕾期到铃期6次叶面喷施1%(质量分数,下同)尿素、0.5%磷酸二氢钾、1%尿素+0.5%磷酸二氢钾3种叶面肥对内蒙古膜下滴灌棉花产量与品质的影响。结果表明,喷施叶面肥处理均比对照增产,皮棉增产幅度为6.0%~10.6%,喷施1%尿素+0.5%磷酸二氢钾处理增产效果最佳。叶面肥处理对棉花纤维品质无显著影响,施用1%尿素+0.5%磷酸二氢钾叶面肥处理棉花纤维上半部平均长度、断裂比强度优于对照。 相似文献
667.
条纹叶枯病是水稻(Oryza sativa L.)上最严重的病害之一。STV11是从籼稻Kasalath中鉴定的条纹叶枯病抗性基因,根据Kasalath型条纹叶枯病基因STV11 KAS6个碱基缺失的功能性多态性序列差异,设计基于PCR的功能性分子标记qstv11。利用此标记对299份试验材料[5份抗病品种、5份感病品种、41份辽宁省育种材料、17份日本粳型材料、142份秋光/七山占重组自交系(群体A)、85份笹锦/Habataki//笹锦回交重组自交系(群体B)、群体亲本4份]进行基因型分析并进行抗病性鉴定。结果表明,qstv11能够较好区分抗感基因型,而且在测试材料中与条纹叶枯抗性整体呈现共分离。41份辽宁材料中鉴定出含有STV11-R(抗)材料1份;日本粳型材料该位点均为STV11-S(感);群体A和B中分别筛选出粳稻背景STV11-R型材料24份和6份。 相似文献
668.
塞罕坝机械林场建场52年来完成了4项历史任务,为京津地区筑起了一道绿色生态屏障,成为京津重要生态区。林场通过内部体制改革,引入竞争机制,实行场长任期目标管理责任制,全面推行绩效工资制度、目标承诺制度和领导包保森林防火风险抵押金制度,着力培育新的产业经济增长点,各项事业健康发展,生态建设取得辉煌成就。但林场发展面临定位不清、体制不顺、生产生活等基础设施相对滞后、社会保障制度不健全等问题。对策:从根本上解决体制问题,明确定位,分类经营,完善社会保障,促进林场稳定与发展。 相似文献
669.
慢性肾病(Chronic kindey disease,CKD)作为高发病率、低防治率的常见疾病之一,目前尚无非人灵长类动物在CKD模型中应用的进展报告。建立CKD模型的非人灵长类动物主要是猕猴属中恒河猴、食蟹猴和豚尾猴3种。从造模方式看,主要采用的方法有诱导性模型和自发性模型两种。诱导型造模可分为药物诱导、免疫诱导、重金属化合物诱导、辐射损伤、生物诱导等不同方法。从肾脏病理改变看,有以肾小球病理改变为主,如猪尾猴疟原虫、牛丙种球蛋白等诱导者;有以肾小管病理改变为主,如氯化镉、顺铂等诱导者;有兼顾肾小球和肾小管损伤,如猴免疫缺陷病毒(SHIV)诱导者。为利用非人灵长类动物进行CKD相关研究提供了方法学汇总,具有一定参考价值。 相似文献
670.
晓文1号甜樱桃新品种具有品质优、抗性强、丰产、稳产等特性,其对园地、砧木、授粉树、栽植密度及整形修剪等都有具体要求,生产中应把握好各项技术,以保证栽培的成功。 相似文献