云南柠檬产业发展的优势与潜力

概述柠檬营养与功能利用价值,以及在云南干湿热"三江并流"区域与次区域的自然生态条件,并从市场前景、发展基础、科技支撑、产业发展瓶颈与发展情景的角度,阐明在云南发展柠檬产业的优势及潜力。     

Soil nutrient status,yield and quality of lemon (Citrus limon Burm.) cv. ‘Assam lemon’ as influenced by bio-fertilizers,organics and inorganic fertilizers

An experiment was conducted at Mizoram University, Aizawl, India during 2015-2017 to study the effect of integrated nutrient management on yield and quality of lemon cv. ‘Assam lemon’ (Citrus limon Burm.). The experiment was comprised of nine treatments viz. T1: 100% recommended dose of fertilizers (RDF) through inorganic fertilizers (IF); T2: 100% N through Farm Yard Manure (FYM); T3: 75% N through FYM + 25% through IF; T4: 50% N through FYM + 50% through IF; T5:75% N through FYM +25% through IF + Azotobacter + phosphate solubilizing bacteria (PSB)+ potash solubilizing bacteria (KSB); T6: 50% N through FYM + 50% through IF+ Azotobacter + PSB?+?KSB; T7: 75% N through FYM + 25% through IF?+?Azospirillum + AMF?+?KSB; T8: 50% N through FYM + 50% through IF+ Azospirillum + arbuscular mychorrhizal fungi (AMF) + KSB; T9: control. Among all treatments, T5 recorded highest value with respect to growth, yield and soil quality. While, T7 showed superiority in quality characters.     

柠檬酒的澄清研究

采用常用的6种澄清剂对柠檬原酒进行了澄清试验。测定澄清处理后柠檬酒的透光度,并对其进行感官评价。结果表明,皂土是最佳的澄清剂,当用量为0.15%,静止澄清8h后,柠檬酒的透光率可达96.7%,而且对柠檬酒的理化指标和感官品质影响较小。     

Influence of supraphysiological cortisol manipulation on predator avoidance behaviors and physiological responses to a predation threat in a wild marine teleost fish

The stress axis in teleost fish attempts to maintain internal homeostasis in the face of allostatic loading. However, stress axis induction has been associated with a higher predation rate in fish. To date, the physiological and behavioral factors associated with this outcome are poorly understood. The purpose of the present study was to investigate the impact of experimental cortisol elevation on anti‐predator behavior and physiological responses to predator presence. We hypothesized that semi‐chronic cortisol elevation would increase susceptibility to predation by increasing stress‐induced risk‐taking behaviors. To test this hypothesis, schoolmaster snapper were given cocoa butter implants without cortisol (sham) or with cortisol (50 mg/kg body weight) and tethered to cover. Fish were exposed to either a lemon shark or control conditions for 15‐min. Space use and activity were recorded throughout and fish were terminally sampled for blood. Cortisol implantation, relative to shams, resulted in higher blood glucose and plasma cortisol concentrations with a lower plasma lactate concentration. Shark exposure, relative to controls, elicited higher blood glucose and lactate concentrations but had no effect on plasma cortisol concentration. No interactions were detected between shark exposure and cortisol treatment for any physiological trait. Behavioral metrics, including shelter use and activity, were unaffected by either cortisol implantation or shark exposure. Physiological responses to cortisol implantation likely resulted from enhanced gluconeogenic activity, whereas alterations under predator exposure may have been the product of catecholamine mobilization. Further work should address context‐specific influences of stress in mediating behavioral responses to predation.     

Characterisation of <Emphasis Type="Italic">Phoma tracheiphila</Emphasis> by RAPD-PCR,microsatellite-primed PCR and ITS rDNA sequencing and development of specific primers for <Emphasis Type="Italic">in planta</Emphasis> PCR detection

Thirty six isolates of Phoma tracheiphila from Italy, the causal agent of the mal secco disease on Citrus species, were characterised by different molecular tools in comparison with representative isolates of other phytopathogenic Phoma species. These included analysis of the distribution of RAPD and microsatellite markers and sequencing of the internal transcribed spacer (ITS) region of the nuclear rRNA genes. The results obtained with 12 RAPD primers (92 markers) and 7 microsatellite primers (56 markers) suggest that Italian isolates of P. tracheiphila are genetically homogeneous, leading to identical patterns upon amplification with all the tested primers. Accordingly, ITSI-5.8S-ITS2 sequences were highly conserved (98–100% identity along a 544-characters alignment) among all the isolates of P. tracheiphila. A neighbor-joining analysis of ITS sequences of P. tracheiphila in comparison with those of other Phoma species, as well as with alignable sequences from anamorphic and teleomorphic taxa retrieved in BLAST searches, revealed a close relationship between P. tracheiphila and Leptosphaeria congesta. A pair of P. tracheiphila-specific primers was designed on the consensus sequence (555 residues) obtained from the alignment of the newly generated P. tracheiphila ITS sequences. A PCR-based specific assay coupled to electrophoretic separation of amplicons made it possible to detect P. tracheiphila in naturally infected Citrus wood tissue collected from both symptomatic and symptomless plants. The limit of detection was 10 pg of genomic DNA and 5 fg of the ITS target sequence.     

氮钾水平与全多酚对柠檬流胶病抗性的影响

Ｎ、Ｋ水平与柠檬抵御流胶病病原菌侵染能力有密切关系。在营养液中Ｎ浓度大于２４０ｍｇ／ｋｇ，树体对流胶病抵御能力降低；在Ｋ浓度小于２２０ｍｇ／ｋｇ范围内，提高Ｋ水平能明显提高树体抗流胶病的能力。叶片中全多酚的含量与树体抗流胶病能力强弱有关，在营养液中Ｎ浓度为２４０ｍｇ／ｋｇ，Ｋ浓度为２２０ｍｇ／ｋｇ时，叶片全多酚含量为９．１７ｍｇ／ｇ，树体具有较强的抗流胶病能力。     

套袋对反季柠檬品质变化的影响

为探讨套袋对柠檬内在品质的影响,选用生产上常用的外黄内黑双层纸袋对尤力克柠檬进行套袋处理,不套袋为对照.结果表明:套袋处理的反季柠檬在生长发育过程中,单果重量、果皮厚度增加幅度大干不套袋柠檬,在花后120～150 d,套袋与不套袋柠檬横径均可达5cm以上;不套袋的反季柠檬出汁率、果汁中维生素C、总酸、固形物含量均高于套袋处理.     

尤力克柠檬上一种新病害的生物学特性及RT-PCR检测

近年我国云南瑞丽市的一果园尤里克柠檬上出现一种引起叶片皱缩、反卷或呈船形,叶背水浸状、侧脉脉明、黄化的柑橘新病害。为明确该病害的病原及其生物学特性,通过田间观察、病样接种、电镜观察,并基于柑橘黄脉病毒(Citrus yellow vein clearing virus,CYVCV)外壳蛋白基因设计引物对病样进行RT-PCR检测。结果表明,该病是一种嫁接传染性病害,能侵染柠檬和酸橙品种且症状明显,并能摩擦接种到辣椒和豇豆等草本植物。该病发病最适温度为18~24℃。春梢嫩叶症状表现明显,夏梢和秋梢基本不表现症状,而晚秋梢也表现出较春梢稍弱的典型症状。引致该病的病毒为(13~15)nm×(400~1 000)nm大小的联合丝状病毒。RT-PCR扩增产物为614 bp,且其与CYVCV外壳蛋白序列相似性达97%以上,表明该病害是由CYVCV引起的柑橘黄脉病,并初步建立了该病的RT-PCR检测技术。     

柠檬柚果实发育过程中金属营养元素含量变化及活性氧代谢研究

研究柠檬柚（Citrus limonum Grandis Osbeck,柠檬与麻豆文旦柚杂交的新品种）果实发育过程中K、Ca、Mg、Zn、Cu、Mn、Fe 7种金属营养元素的含量与分布、吸收规律及其与活性氧代谢的相关性。结果表明：（1）4—5月、6—9月和10—11月分别是果皮迅速生长期、果肉迅速生长期和果实转色成熟期。（2）果皮和果肉中K、Ca、Mg、Zn、Mn、Fe的含量都随着果实的发育总体呈递减规律,但元素的吸收总量却相反。K、Zn、Fe以果肉居多,Ca、Mg、Mn则主要分布在果皮。K含量位居7元素之首。Cu在幼果期的含量是其它月份的5 ~ 6倍,且果皮果肉中的含量相当。（3）K、Ca、Mg、Zn、Mn的吸收量集中在7—9月,Cu和Fe 的吸收高峰则在11月果实转色期（39.83%和45.95%）。（4）果肉中7种金属营养元素间相关性显著率大于果皮。（5）与活性氧代谢相关性较显著的是Fe元素,其余依次是K、Zn、Cu、Ca、Mg,Mn最低。