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161.
摘要:由于立柱基质栽培设施存在上下层水肥供应不均和阴阳面光照不均的问题,导致了蔬菜长势不均进而影响高产,为了解决这些问题,引入TRIZ理论,根据TRIZ一般解题流程,首先陈述具体技术问题,然后抽象为TRIZ通用问题模型,再运用TRIZ工具得到通用的解决方案模型,共获得16种解决方案,最后结合实际,通过方案评价进行选择和技术集成,最终优选出“立体水培(或气雾培)+动态旋转+周期性供水肥”的集成方案,解决了立柱基质栽培水肥供应不均和光照不均的问题,有望进一步实现蔬菜无土栽培提质增产。 相似文献
162.
Marine Remize Frdric Planchon Matthieu Garnier Ai Ning Loh Fabienne Le Grand Antoine Bideau Christophe Lambert Rudolph Corvaisier Aswani Volety Philippe Soudant 《Marine drugs》2022,20(1)
The production of polyunsaturated fatty acids (PUFA) in Tisochrysis lutea was studied using the gradual incorporation of a 13C-enriched isotopic marker, 13CO2, for 24 h during the exponential growth of the algae. The 13C enrichment of eleven fatty acids was followed to understand the synthetic pathways the most likely to form the essential polyunsaturated fatty acids 20:5n-3 (EPA) and 22:6n-3 (DHA) in T. lutea. The fatty acids 16:0, 18:1n-9 + 18:3n-3, 18:2n-6, and 22:5n-6 were the most enriched in 13C. On the contrary, 18:4n-3 and 18:5n-3 were the least enriched in 13C after long chain polyunsaturated fatty acids such as 20:5n-3 or 22:5n-3. The algae appeared to use different routes in parallel to form its polyunsaturated fatty acids. The use of the PKS pathway was hypothesized for polyunsaturated fatty acids with n-6 configuration (such as 22:5n-6) but might also exist for n-3 PUFA (especially 20:5n-3). With regard to the conventional n-3 PUFA pathway, Δ6 desaturation of 18:3n-3 appeared to be the most limiting step for T. lutea, “stopping” at the synthesis of 18:4n-3 and 18:5n-3. These two fatty acids were hypothesized to not undergo any further reaction of elongation and desaturation after being formed and were therefore considered “end-products”. To circumvent this limiting synthetic route, Tisochrysis lutea seemed to have developed an alternative route via Δ8 desaturation to produce longer chain fatty acids such as 20:5n-3 and 22:5n-3. 22:6n-3 presented a lower enrichment and appeared to be produced by a combination of different pathways: the conventional n-3 PUFA pathway by desaturation of 22:5n-3, the alternative route of ω-3 desaturase using 22:5n-6 as precursor, and possibly the PKS pathway. In this study, PKS synthesis looked particularly effective for producing long chain polyunsaturated fatty acids. The rate of enrichment of these compounds hypothetically synthesized by PKS is remarkably fast, making undetectable the 13C incorporation into their precursors. Finally, we identified a protein cluster gathering PKS sequences of proteins that are hypothesized allowing n-3 PUFA synthesis. 相似文献
163.
LIU Weichao FU Shuyue YAN Shengji REN Chengjie WU Shaojun DENG Jian LI Boyong HAN Xinhui YANG Gaihe 《干旱区科学》2020,12(2):215-226
Succession is one of the central themes of ecology;however,the relationship between aboveground plant communities and underground soils during secondary succession remains unclear.In this study,we investigated the composition of plant community,plant-soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0,10,20,30,40 and 50 a in China,2016.Results showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 a.Soil organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a,but both were significantly higher than those of control farmland(31.21%-139.10%and 24.24%-121.21%,respectively).Moreover,C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands,explaining 35.70%of the total variation.Particularly,soil C:N ratio was significantly and positively related with the Shannon-Wiener index.This study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them. 相似文献
164.
根据胡椒4-香豆酸:辅酶A连接酶(4-coumarate:coenzyme A ligase, 4CL)基因的部分序列设计引物,运用RACE方法获得其家族成员的1个全长cDNA,命名为Pn4cl,长度2130 bp,开放阅读框1638 bp,编码545个氨基酸。预测Pn4CL分子量为59.57 kDa,理论等电点为5.70。该基因含有AMP-binding(AMP-binding enzyme)、CaiC[Acyl-CoA synthetase (AMP-forming) /AMP-acid ligaseⅡ]、PLN02246、AFD-class I等结合域,具有植物4CL所共有的保守结构域。系统进化分析表明,Pn4CL与北细辛的同源性最高,同时与木兰分支类植物的4CL聚类在一起,与菊分支的进化距离较近,与蔷薇分支的进化距离较远。亚细胞定位表明,该蛋白定位在细胞膜上。Real-time RT-PCR结果表明,该基因受外援激素SA和MeJA诱导表达,同时接种辣椒疫霉菌后,Pn4CL基因的表达量在抗/感2种胡椒中均出现先增加后减少的现象,并且在抗病种质中表达量较高。研究结果为Pn4CL的功能研究提供了理论依据。 相似文献
165.
AIMTo investigate the role of soluble Klotho protein in THP-1-derived foam cell formation. METHODSTHP-1 monocytes were induced into macrophages by treatment with 160 nmol/L phorbol myristate acetate for 48 h, and then were divided into 6 groups: negative control group (THP-1-derived macrophages), positive control group [THP-1-derived foam cells induced by oxidized low-density lipoprotein (ox-LDL) for 48 h], and 25, 50, 100 and 200 μg/L soluble Klotho protein groups (THP-1-derived macrophages pretreated with soluble Klotho protein at the indicat?ed concentraions for 2 h and then induced by ox-LDL for 48 h). Lipid droplets in cytoplasm were observed by oil red O staining. The cholesterol outflow rate was detected by scintillation counting technique. The content of intracellular total cholesterol, free cholesterol and cholesterol ester was detected by enzyme fluorescence analysis. The expression of acyl-coenzyme A:cholesterol acyltransferase 1 (ACAT1) and ATP-binding cassette transport?er A1 (ABCA1) at mRNA and protein levels was determined by RT-qPCR and Western blot, respectively. RESULTSOil red O staining and lipid mass quantification showed that THP-1-derived foam cell formation was dose-dependently suppressed by soluble Klotho protein. The cholesterol efflux rate of THP-1-derived foam cells was increased by soluble Klotho protein in a dose-dependent manner (P <0.05). In addition, soluble Klotho protein decreased the expression of ACAT1 and increased the expression of ABCA1 in a dose-dependent manner (P <0.05). CONCLUSION The soluble Klotho protein inhibits THP-1-derived foam cell formation in a dose-dependent manner by down-regulating the expression of ACAT1 and up-regulating the expression of ABCA1. 相似文献
166.
为了培育辣椒壮苗,在潮汐灌溉模式下筛选适合辣椒穴盘育苗的营养液,探讨不同营养液在辣椒穴盘育苗上应用的可行性,以国塔166为试材,以草炭、蛭石(体积比3∶1)为栽培基质,进行试验研究。试验采用6种营养液配方,通过测定株高、茎粗、干鲜质量、壮苗指数、叶绿素含量、光合参数、根系活力、根系形态等指标,筛选最优营养液配方。结果表明:Arnon和Hoagland 番茄配方处理辣椒幼苗的株高、茎粗、地上鲜质量、地上干质量、叶绿素含量、净光合速率、气孔导度、壮苗指数、根尖数等指标均最高,其中壮苗指数分别较日本山崎番茄、Hoagland和Arnon、华南农业大学、Rothamsted、日本山崎甜椒配方高出44.44%、62.50%、30.00%、116.67%、62.50%。综上可知,Arnon和Hoagland 番茄配方是潮汐灌溉模式下辣椒穴盘育苗的最佳配方。 相似文献
167.
为探究甜瓜嫩果皮颜色的遗传规律,以甜瓜嫩果皮颜色为深绿色的S26和青色的S28为亲本材料,通过构建BC1群体,利用卡方测验,分析回交群体BC1的深绿色嫩果皮和青色嫩果皮的分离比例,开展甜瓜嫩果皮的遗传规律分析,以对嫩果皮颜色基因进行初步定位。结果表明:BC1群体表型表现为深绿色和青色2种,且群体比例为1∶1,从而确定颜色性状为单基因控制且深绿色为显性性状。通过分离群体分组分析法(BSA)和混池测序结果可以看出,控制甜瓜嫩果皮颜色的基因位于chr04的端部位置,这为后续基因的精细定位以及克隆提供了研究基础。 相似文献
168.
169.
以番茄品种"福美十号"为材料,采用随机区组试验设计,研究不同基质配比对番茄幼苗生长与叶片叶绿素荧光参数的影响。结果表明:采用A3[V(草炭)∶V(玉米秸秆)∶V(牛粪)∶V(食用菌下脚料)∶V(蛭石)=1∶2∶0.5∶0.5∶1]的基质配比,幼苗在出苗率、株高、茎粗、叶片数和根冠比等性状上表现最优,分别为98.25%、44.60 cm、0.50 cm、9.12片与7.95;叶片光系统Ⅱ(PSIⅡ)原初光能转化效率(Fv/Fm)与PSⅡ潜在活性(Fv/Fo)的值在幼苗生长前期、中期和末期也均为最高,Fv/Fm值分别为0.82、0.74和0.79,Fv/Fo值分别为3.92、2.97和3.23;其叶片内丙二醛(MDA)含量最低为6.02μmol/g,其根系活力最强、超氧化物歧化酶(SOD)、过氧化物酶(POD)与可溶性蛋白含量等指标最高,分别为158.26μg/(g·h)、386.23 U/g、6.26 U/(g·min)和0.203 mg/g,显著高于其他处理。说明采用处理A3的基质配比更适宜于番茄幼苗的生长。 相似文献
170.
为了探索福建省茎用芥菜1年2代繁育技术,选择6个茎用芥菜品种,分别进行冬春季正常繁育和夏秋季高山加代繁育的2代繁育试验,并对比各品种2代繁育的生育期、株高、株幅和种子产量。结果表明:所有参试茎用芥菜品种只要通过打破种子休眠、衔接好2代繁育的播种期都能完成1周年2代繁育,夏秋季高山加代繁育的全生育期比冬春季正常繁育平均缩短约50 d;冬春季繁育比夏秋季高山加代繁育株高增加31.2%~132.9%,株幅增加1.5%~21.8%,所有参试品种冬春季繁育的种子产量都极显著高于相应夏秋季高山加代繁育,种子产量增加17.8%~153.6%。 相似文献