滇中冷凉山区不同播期反季花椰菜产量效益分析     

李艳兰  张云明  李祥  胡新洲  段永华  刘坚坚  安正云  易丽华  蔡述江  王爱明  陶春红  史兰芬  李文静  杨进成 《农学学报》2021,11(9):58-63

为摸索滇中高海拔冷凉山区反季节栽培花椰菜的最佳播期以集成高效栽培技术推广应用,于2017—2018年选择海拔2250 m的云南省峨山县塔甸镇大西村地块进行9个播期的2年随机区组试验。结果表明,花椰菜生育期随播期推迟而延长,而花球采收期除播期7月10日外随播期推迟而逐渐增长;花椰菜株高、外叶数、开展度、球高、球径和单球重等农艺性状有随播期延迟呈现先逐渐减小而后又逐渐增大的趋势;莲座期黑腐病和霜霉病的病情指数随着播期的延迟呈现先逐渐升高而后又逐渐下降的趋势;花椰菜小区产量随着播期的延迟呈现先逐渐下降而后又逐渐提高的趋势,播期4月20日和4月30日与其余7个播期产量之间的差异达极显著水平。综合花椰菜在冷凉山区反季节栽培的生产实际和各播期产量产值及商品性表现,推荐滇中高海拔冷凉山区反季节栽培花椰菜的最佳播期为4月20—30日。  相似文献   

马铃薯致病疫霉拮抗细菌研究进展     

高梦颖  付海燕  孙丛  王颜波  刘春光  马玉堃  杨峰山 《中国农学通报》2021,37(14):136-140

为了解决马铃薯致病疫霉侵染马铃薯导致其死亡,进而造成马铃薯单位种植产量低的问题。本文从拮抗菌入手,归纳分析细菌类拮抗菌中的主要拮抗菌中芽孢杆菌、假单胞菌和粘细菌对马铃薯致病疫霉的抑制作用。同时,在总结前人研究的基础上,笔者认为在拮抗菌应用方面,可以采用多对一的新型平板对峙筛菌模式来模拟复杂条件下拮抗菌的拮抗作用,以期得到稳定的拮抗菌;并指出应从定植能力和根际微生物影响方面对拮抗菌实际应用的可行性进行研究;此外,提出未来对拮抗菌抑制马铃薯致病疫霉的探究应从表型层面的研究深入到分子层面,以期能成功从源头找寻抑制马铃薯致病疫霉的答案。  相似文献   

玉米秸秆消化率全基因组关联分析     

林淼  张秋芝  史利玉  刘蓓  王红武  潘金豹 《作物杂志》2020,36(6):23-4

48h体外干物质消化率（48h in vitro dry matter digestibility, 48h IVDMD）是衡量青贮玉米品质的重要指标。为了初步探究玉米秸秆消化率的分子遗传机理,以341份玉米自交系为材料,于2018年在沈阳和通辽种植,收获后测定秸秆48h IVDMD。利用全基因组重测序获得的6 276 612个高质量SNPs进行全基因组关联分析,共检测到153个与玉米秸秆消化率显著相关的SNPs位点（P<1.0×10^-6）,4个SNPs显著水平在P<1.0×10^-8以上;共找到38个秸秆消化率的候选基因,主要涉及细胞生长发育、防御反应和信号转导等生物学功能。  相似文献   

叶面滞尘量对大叶黄杨光谱特征影响研究     

苏凯  于强  孙小婷  岳德鹏 《北京林业大学学报》2021,43(11):40-49

  目的  叶面滞尘会影响植被光谱特征，削弱植被指数对植被的响应能力，影响反演评估的准确性。为探究叶面滞尘量对植被光谱响应特征及预测模型的影响，本文以北京市常见常绿绿化树种大叶黄杨为研究对象展开研究。  方法  从封闭区域、半封闭区域、开放区域，采集叶片样本，并收集环境灰尘。通过室内控制试验，利用ASD FildSpec Handheld光谱仪测量不同滞尘量叶片的高光谱数据，选取5个特征波段，通过光谱角的方法研究了叶面滞尘量对叶片光谱特征的影响，以及滞尘量对叶面滞尘量预测模型的精度和稳定性影响。  结果  随着叶面滞尘量的增加，植被光谱曲线特征逐渐减弱，灰尘的特征逐渐增强，但光谱曲线的总体变化趋势基本一致。当叶面滞尘量 > 120 g/m2时，光谱曲线的基本表现为灰尘的光谱特征。当叶面滞尘量较少时，预测模型的模拟精度相对较高，随着滞尘量的增加，所有模拟预测模型的决定系数均减小；当叶面滞尘量 > 120 g/m2时，预测模型对叶面滞尘量的模拟预测能力将更差，并且均方根误差（RMSE）随着叶片单位面积滞尘量的增加而增大，模拟预测模型的稳定性及预测精度逐渐降低。光谱角对滞尘叶片350 ~ 1 770 nm波段区间的光谱变化十分敏感，利用叶片光谱角检测滞尘程度不需要分区域讨论，只需与阈值做简单的比较，方法简便易行。  结论  本研究通过室内控制试验，研究叶面滞尘量对植被光谱响应特征，可为建立滞尘植被光谱反射物理模型提供参考与借鉴。   相似文献   

Correction to: Predation on glass eels of Japanese eel <Emphasis Type="Italic">Anguilla japonica</Emphasis> in the Tone River Estuary,Japan     

Yoichi Miyake  Aigo Takeshige  Hikaru Itakura  Hajime Itoh  Hiroaki Onda  Akira Yamaguchi  Akihito Yoneta  Kohma Arai  Yulina V. Hane  Shingo Kimura 《Fisheries Science》2018,84(6):1015-1016

  相似文献   

我国牧草种植成本收益变化与比较     

石自忠  王明利  胡向东  崔姹 《草业科学》2017,34(4)

本研究以牧草种植户牧草及粮食作物的调研数据为基础,计算出2010-2014年主要牧草和粮食作物的成本收益基本信息,对其变化进行统计分析,并对各作物的成本收益进行比较。分析发现,2014年苜蓿(Medicago sativa)的经济效益有所下降;黑麦草(Lolium perenne)和青贮玉米(Zea mays)的纯收益和收益率有所增长;苜蓿的纯收益和收益率要高于黑麦草和青贮玉米;马铃薯(Solanum tuberosum)和苜蓿的经济效益更具优势,种植小麦(Triticum aestivum)经济效益较差;黑麦草和青贮玉米人工和土地成本更高,苜蓿水电费最高。建议调整农业产业结构,推行"粮+经+饲+草"四元种植结构,全面扶持牧草产业发展,建立健全牧草生产资料补贴制度。  相似文献   

Dietary Lipid Levels Affect the Growth Performance,Lipid Deposition,and Antioxidative Capacity of Juvenile Scaleless Carp,Gymnocypris przewalskii,on the Qinghai‐Tibetan Plateau          下载免费PDF全文

Qiwei Qin  Yanlin Tong  Ruman Zhu  Guoqian Xu  Yuan Shi  Jianquan Shi  Rui Ma 《Journal of the World Aquaculture Society》2018,49(4):788-797

A 56‐d growth trial was conducted to evaluate the growth performance, lipid deposition, and antioxidative capacity of juvenile scaleless carp, Gymnocypris przewalskii, on Qinghai‐Tibetan Plateau. One‐year‐old juveniles (initial weight: 15.99 ± 0.02 g) were fed practical diets with different lipid levels of 4, 5.5, 7, 8.5, and 10%, respectively. Results showed that the best specific growth rate (SGR), feed conversion rate, and total antioxidative capacity (T‐AOC) in hepatopancreas were observed in fish fed the diet with 7% lipid level. Fish fed with high lipid diets (8.5 and 10%) had significantly higher condition factor and viscerosomatic index as well as lipid in muscle, intestine, mesenteric fat tissue, and whole body. Highest level of hepatopancreas lipase and lipoprotein lipases activities as well as malondialdehyde content and the lowest level of feed intake and T‐AOC content in hepatopancreas and intestine were also observed in fish fed with high lipid diets (8.5 and 10%) (P < 0.05). In conclusion, based on SGR and hepatopancreas T‐AOC content, dietary lipid requirement of juvenile G. przewalskii was estimated to be 7.35 and 7.39%, respectively.  相似文献   

正交设计优化青蒿SRAP-PCR反应体系及引物筛选     

石紫薇  梁妍  姜婷婷  梁剑平  贾宁  辛志君  陆锡宏  周翔  李雪虎 《分子植物育种》2020,(10):3303-3310

为了建立青蒿的SRAP最佳扩增体系,并筛选出SRAP多态性引物,本研究以青蒿叶片DNA为模板,采用正交试验设计,以Mg^2+、dNTP Mix、Taq DNA聚合酶、引物和DNA模板5种因素5个水平,对青蒿SRAP反应体系进行研究。结果表明,青蒿SRAP-PCR最佳反应体系为:引物0.6μmol/L、Mg^2+2.0 mmol/L、模板DNA 5.1 ng、Taq DNA聚合酶2.0 U、dNTPs 0.25 mmol/L,总体积为25μL。各因素对扩增反应均有不同影响,其中引物浓度的影响最大,dNTPs的影响最小。运用该体系对不同种质资源的青蒿进行验证,证明该体系稳定可靠,并在30个引物组合中筛选出了25对扩增条带清晰,多态性丰富的引物组合。这一结论为今后利用SRAP标记技术进行青蒿分子遗传学研究提供了科学依据。  相似文献   

New Polyketides from the Antarctic Fungus Pseudogymnoascus sp. HSX2#-11     

Ting Shi  Yan-Yan Yu  Jia-Jia Dai  Yi-Ting Zhang  Wen-Peng Hu  Li Zheng  Da-Yong Shi 《Marine drugs》2021,19(3)

The species Pseudogymnoascus is known as a psychrophilic pathogenic fungus with a ubiquitous distribution in Antarctica. Meanwhile, the study of its secondary metabolites is infrequent. Systematic research of the metabolites of the fungus Pseudogymnoascus sp. HSX2#-11, guided by the method of molecular networking, led to the isolation of one novel polyketide, pseudophenone A (1), along with six known analogs (2–7). The structure of the new compound was elucidated by extensive spectroscopic investigation and single-crystal X-ray diffraction. Pseudophenone A (1) is a dimer of diphenyl ketone and diphenyl ether, and there is only one analog of 1 to the best of our knowledge. Compounds 1 and 2 exhibited antibacterial activities against a panel of strains. This is the first time to use molecular networking to study the metabolic profiles of Antarctica fungi.  相似文献   

EPS364, a Novel Deep-Sea Bacterial Exopolysaccharide,Inhibits Liver Cancer Cell Growth and Adhesion     

Yun Wang  Ge Liu  Rui Liu  Maosheng Wei  Jinxiang Zhang  Chaomin Sun 《Marine drugs》2021,19(3)

The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a β-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy.  相似文献