Evaluation of Resistance of Different Kiwifruit Varieties (Lines) to Canker Disease and Brown Spot Disease

Kiwifruit canker and brown spot are significant diseases affecting kiwis,caused by Pseudomonas syringae patho-genic variations(Pseudomonas syringae pv.Actinidiae(Psa))and Corynesporapolytica(Corynespora cassiicola).At present,the research on canker disease and brown spot disease mainly focuses on the isolation and identification of pathogenic bacteria,drug control,resistance gene mining and functional verification.Practice has proved that breeding disease resistant varieties are an effective method to control canker disease and brown spot disease.However,most existing cultivars lack genes for canker and brown spot resistance.Wild kiwifruit resources in nat-ure exhibit extensive genetic diversity due to prolonged natural selection,containing numerous resistance genes.But,due to insufficient understanding of the resistance of most kiwifruit varieties(lines)to canker disease and brown spot disease,some high-quality resources have not been fully utilized.The incidence of canker and brown spot of 18 kiwifruit cultivars(lines)was measured by inoculating isolated branches and leaves,and their resistance to canker and brown spot was analyzed according to the length,disease index,mean diameter,and systematic clustering.The results were as follows:Among 18 different kiwifruit varieties(lines)for canker disease,there were two highly resistant materials,eight disease-resistant materials,four disease-susceptible materials,and two highly susceptible materials.Moreover,regarding brown spot disease,there were one highly resistant material,five dis-ease-resistant materials,four susceptible materials,and three highly susceptible materials.Furthermore,four resources were resistant to both diseases.The outcomes provided a theoretical basis for breeding kiwifruit against canker and brown spot.

Effects of fresh-cut and storage on glucosinolates profile using broccoli as a case study

Glucosinolates(GLS) contribute to the unique flavour, nutrition, and plant defence of the Cruciferous vegetables. Understanding the GLS changes through postharvest processing is essential for defined preservation. In this study, four different fresh-cut types, whole flower(W),floret(F), quarterly cut floret(QF) and shredded floret(FS) of broccoli, were stored for 0, 1, 2 and 3 day(s) to explore GLS responses to postharvest treatments. As a result, seven GLS were identified, mainly including glucoraphanin(RAA), neoglucobrassicin(NEO), and glucobrassicin(GBC)and accounting for 52.69%, 20.12% and 14.99% of the total GLS(21.92 ± 0.48) μmol · g ^(-1 )DW, respectively. FS had the sharpest decrease in GLS after three days of storage(6.55 ± 0.37) μmol · g-1DW, while QF had the least(10.16 ± 0.33) μmol · g ^(-1 )DW. All GLS components decreased over storage, except for 4-methoxyglucobrassicin(4 ME) in FS and QF, suggesting its key role in serious wound defence. The results suggested certain postharvest approaches influenced the flavour and nutrition of broccoli.

Efficacy of a Kiwifruit Extract (PhenActivTM) on Gastrointestinal Tract Function: A Randomised Double-Blind Placebo-Controlled Study

Objective: Gastrointestinal (GI) discomfort is experienced by millions of people every day. This study aimed to evaluate the effect of PhenActivTM, a novel green kiwifruit extract, on gastrointestinal tract (GIT) function in otherwise healthy adults. Methods: 41 healthy adults with mild GI discomfort were enrolled in this double-blind, randomized, placebo-controlled study. Participants were randomized to either take 3.0 g/day of PhenActivTM or a placebo for 6 weeks. Interviews were conducted at baseline, week 3 and week 6, with participants completing questionnaires regarding GI symptoms. Frequency of bowel movements was self-recorded daily. Results: There were no differences in daily and weekly defecation frequency and stool characteristics in either group. The active and placebo groups significantly improve GSRS scores (p , only the active group had a significant improvement in the IBSSS and PAC-QOL scores (p < 0.05) from baseline. Neither group had changes in sleep quality, quality of life and fatigue, plasma zonulin concentrations or macular pigment optical density scores. The product was well tolerated with no GI disturbances or adverse events being reported. Conclusion: Supplementation of 3.0 g/day of PhenActivTM for 6 weeks did not improve defecation frequency or stool composition in healthy adults, but did improve perceived symptoms of GIT function, including symptoms of functional GIT disorders, IBS and constipation. The product was well tolerated and future trials investigating higher doses with more participants and/or a different population would be beneficial.

Investigation and Identification of Fungal Diseases of Kiwifruit in Qiandongnan Prefecture

[Objectives]The paper was to investigate and identify the fungal diseases of wild and red heart kiwifruit in Qiandongnan Prefecture.[Methods]The pathogenic fungi were isolated from diseased leaves and fruits of wild and red heart kiwifruit by tissue separation method.DNA sequencing was carried out by using the sequence analysis of ribosomal r DNA-ITS region,and molecular evolutionary trees were built by using MEGA 4.0 software.Finally,the pathogenic fungi were classified and identified by combining morphological observation.[Results]The main fungal diseases were anthracnose caused by Colletotrichum gloeosporioides on wild kiwifruit,fruit anthracnose caused by C.acutatum on red heart kiwifruit,leaf soft rot caused by Fusarium incarnatum on red heart kiwifruit,and brown spot caused by Alternaria alternata on red heart kiwifruit.[Conclusions]The study may provide some theoretical basis for the control of kiwifruit diseases in Qiandongnan Prefecture.

Effect of Magnetic Field Technology on Preservation Quality of Fresh-cut Apple

[Objectives]The paper was to study the effect of magnetic field technology on physicochemical properties of fresh-cut apple during storage.[Methods]Using fresh-cut apples as materials,magnetic field assisted refrigeration and conventional refrigeration control groups were set up,and the preservation effects of magnetic field assisted refrigeration on fresh-cut apples were tested by measuring the changes of microorganisms and physicochemical indicators.In this experiment,the conditions of magnetic field assisted refrigeration group was set as follows:temperature 4℃,magnetic field intensity 5 mT,static magnetic field,and storage for 6 d.[Results]At 6 d post storage,the weight loss rate,total number of colonies and total number of fungi of fresh-cut apples increased;the L value and hardness showed a downward trend;the soluble solid content first increased and then decreased;and the total acid decreased first and then increased.The above indicators in magnetic field assisted refrigeration group changed more gently than that in conventional refrigeration group.Compared with conventional assisted refrigeration,the weight loss rate of fresh-cut apples treated by magnetic field combined with 4℃refrigeration was reduced by 68.00%;the hardness was increased by 12.23%;the total number of colonies and total number of fungi were reduced by 64.15%and 37.50%;and the L value did not change much.High content of soluble solids and total acid was maintained.[Conclusions]Magnetic field assisted refrigeration delays quality deterioration of fresh-cut apples during storage,prolongs shelf life,and further improves their edible quality and commodity value.

氯吡脲处理对脐红猕猴桃果实品质的影响

脐红为深受市场欢迎的黄肉红心芽变猕猴桃新品种,研究不同浓度氯吡脲处理对其果实品质的影响,对脐红猕猴桃生产具有重要指导意义。设置5、10 mg/L氯吡脲水溶液2个处理,在谢花后25 d进行浸果,以清水为对照(CK),于果实成熟期测定果实的外观品质、内在品质、矿质元素及水解氨基酸含量。结果表明:10 mg/L氯吡脲水溶液处理后的单果重、横径、侧径、可溶性固形物含量、固酸比均增幅最大,分别提高了32.26%、17.09%、12.45%、9.38%和18.73%;可滴定酸、维生素C、花色苷含量和钙元素含量则显著降低,分别降低了7.75%、17.05%、52.13%和28.30%。在单个氨基酸方面,胱氨酸和精氨酸等2种氨基酸含量随氯吡脲浓度的增加而显著降低,丝氨酸、甘氨酸、脯氨酸等3种氨基酸含量则显著提高,总氨基酸含量有所降低,但差异不显著。在不同类别氨基酸方面,甜味氨基酸含量随着氯吡脲浓度的增加而提高,鲜味氨基酸、芳香氨基酸含量则降低。综上,氯吡脲的施用可促进脐红猕猴桃果实膨大,增加果实风味,如提高可溶性固形物含量、降低可滴定酸含量,但高浓度处理降低了果实营养品质,如维生素C、花色苷、钙元素、鲜味氨基酸和芳香氨基酸含量。建议种植户合理施用氯吡脲,以促进脐红猕猴桃产业健康可持续发展。

电感耦合等离子体发射光谱(ICP-OES)法测定陕西眉县猕猴桃矿物质含量及相关营养评价

为探究陕西眉县所产猕猴桃中矿物质含量及评价其相关营养价值。利用电感耦合等离子体发射光谱(ICP-OES)法对陕西眉县主产的徐香、翠香、红心、黄心四个品种猕猴桃中9种矿物质含量进行测定,并采用营养质量指数法(Index of nutritional quality,INQ)对矿物质元素进行营养评价,同时应用SPSS软件对9种矿物质和能量进行相关性分析。陕西眉县四个品种猕猴桃矿物质均以钾、磷、钙、镁四种元素为主,约占总矿物质的99.8%,四个品种中INQ均大于1的矿物质有钙、钾、镁、铜,其中钾的INQ最高在3.89~5.19。矿物总量最高的品种为翠香328 mg/100g,但营养质量指数最高的为徐香16.78(INQ_总)。通过相关性分析表明各元素间存在着不同程度的相关性,其中钾与能量的相关系数最高为0.982。猕猴桃是一种高钾低钠的优质食品,不同品种猕猴桃矿物质元素的营养价值差异明显,矿物质营养密度最高的为翠香,其次为红心、黄心、徐香,但从营养价值指数方面来看,徐香最高,翠香次之,红心和黄心猕猴桃矿物营养水平稍逊。

猕猴桃采后真菌病害生物防治研究进展

猕猴桃果实易受多种病原真菌的侵染,采后易发生软腐病、灰霉病、青霉病等严重危害果实品质的真菌性病害。传统的有效防治方法主要为采前使用化学杀菌剂,但其易污染环境并可能危害人类健康。目前,已有一系列生物防治方法被研究并报道,这些方法可有效防控猕猴桃采后真菌病害:第一类为天然抑菌物质,包括植物提取物和其他天然物质;第二类为拮抗微生物,包括生防酵母、生防细菌、生防木霉,生防菌也能与物理及化学方法协同发挥作用。本文概述了各类生物防治方法在猕猴桃采后真菌病害绿色防控方面的研究进展及生防机理,并提出了目前存在的问题,最后展望了这一领域今后的研究方向。

猕猴桃便携式无损检测仪影响因素及其精度校准分析

为探究产地、成熟度对便携式可溶性固形物无损检测精度的影响,以同一品种3个产地的猕猴桃为试材,分别采用便携式无损检测仪和常规有损检测仪对其可溶性固形物含量进行测定和比较,并运用人工神经网络对其进行分析。结果表明,在使用便携式无损检测仪对猕猴桃可溶性固形物检测时,3个产地的无损检测R2分别为0.26、0.52、0.61,成熟度会对其检测精度造成一定影响,但在不同产地间没有稳定、统一的规律;基于人工神经网络学习、建模产生的随机预测值可将R2提高5%~49%。因此,可利用预测值来作为中间校准程序,以辅助提高便携式无损检测精度。

猕猴桃9个种41份种质花粉形态观察与分析

为了解猕猴桃属植物间的亲缘关系,以9个猕猴桃种41份种质的花粉为供试材料,采用扫描电镜结合ImageJ图像处理软件对花粉进行形态学观测,并根据花粉极轴长度(P)、赤道轴长度(E)、萌发沟长度、萌发沟宽度、极轴长度/赤道轴长度(P/E)和大小(P×E)指标对供试材料进行聚类分析。结果表明,供试花粉均为单粒花粉,均以单粒、等极和辐射对称形式存在。极轴长度范围在21.50~33.40μm之间,赤道轴长度范围在9.87~16.24μm之间,萌发沟长度范围在17.53~29.08μm之间,萌发沟脊宽度范围在0.47~2.03μm之间,花粉粒大小(极轴×赤道轴)范围在218.68~543.18μm^(2)之间,极轴长度/赤道轴长度范围为1.36~2.26,花粉形状为超长球形或长球形,萌发孔类型均为三孔沟,极面观为三裂圆形,均为N3P4C5型。外壁纹饰分为波纹状、颗粒状和疣状,占样品总数的比例分别为63.41%、19.51%和17.08%。在遗传距离为7.5时,供试材料可以分为3个类群;在遗传距离为1.5时,供试材料可以分为6个类群,其中,中华猕猴桃被分为了4类。在两个遗传距离时,四萼猕猴桃均单独分为一类。

3株生防菌对猕猴桃软腐病的作用

为探究生防菌对猕猴桃软腐病的作用,选用前期获得的3株生防菌(贝莱斯芽孢杆菌P2-1、耐盐芽孢杆菌PL7和多黏芽孢杆菌NL4)进行室内抑菌试验、猕猴桃软腐病接种和自然发病防治试验,并研究了3株生防菌对猕猴桃果实病程相关基因表达的影响。试验结果表明,菌株P2-1、PL7和NL4对猕猴桃软腐病菌(Botryosphaeria dothidea)菌丝生长的抑制率分别为83.49%、74.82%和49.33%,P2-1的抑制效果最好,PL7次之,NL4最差;3株生防菌对接种猕猴桃软腐病均具有抑制作用,其中以P2-1的效果最好,PL7次之,NL4最差;3株生防菌均能显著降低猕猴桃软腐病自然发病率,其中以P2-1处理的发病率最低;3株生防菌处理均对猕猴桃果实品质无影响;3株生防菌处理猕猴桃果实后,果实中基因PR1、PR5和SOD的表达显著上调。研究结果可为菌株P2-1、PL7和NL4开发为防治猕猴桃软腐病的生物制剂提供参考。

猕猴桃酵素发酵工艺优化及体外抗氧化活性测定

为进一步延伸猕猴桃加工链,该研究以猕猴桃为原料,通过单因素试验、Plackett-Burman试验和响应面试验优化猕猴桃酵素发酵工艺,并分析猕猴桃酵素对2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸(ABTS^(+))、1,1-二苯基-2-三硝基苯肼(DPPH)、羟基自由基清除效果及Fe^(3+)的相对还原能力。结果表明,猕猴桃酵素最佳发酵工艺为料液比38∶100(g∶mL)、菌种(酿酒酵母∶植物乳杆菌∶保加利亚乳杆菌=3∶1∶1)接种量0.24%、白砂糖添加量12%,发酵时间144 h,发酵温度26.4℃。在最佳工艺条件下制备的猕猴桃酵素超氧化物歧化酶(SOD)酶活力可达1893.30 U/mL。抗氧化试验结果表明,猕猴桃酵素对DPPH·、ABTS^(+)·、·OH清除率及Fe^(3+)相对还原能力分别为37.2%、80.13%、79.01%及24.65%;分别比优化前提高了7.98%、2.50%、2.41%及3.58%。综上,经过发酵工艺优化后猕猴桃酵素SOD酶活增加,抗氧化活性有所提升。

猕猴桃根腐病根际土壤酶活性及真菌群落组成研究

分析猕猴桃根腐病感病植株和未感病植株根际土壤真菌群落差异,可为研究猕猴桃根腐病发生机制及其调控技术提供依据。在浙江省天台县街头镇的“红阳”猕猴桃种植基地,以树龄9年的猕猴桃根腐病感病植株和未感病植株根际土壤真菌为研究对象,对菌群ITS序列进行高通量测序注释后,对比分析了真菌群落结构与多样性指数的差异,并测定分析了根际土壤脲酶、蔗糖酶和酸性磷酸酶的活性。结果表明,猕猴桃根腐病的发生极显著地降低了根际土壤脲酶、蔗糖酶和磷酸酶的活性(p<0.01)。感病植株根际土壤真菌群落丰富度指数(Chao1)显著低于未感病植株根际土壤(p<0.05)。在门分类水平上,感病植株根际土壤真菌中相对丰度降低的有担子菌门、未分类真菌和接合菌门,其差异均为极显著(p<0.01);相对丰度升高的为子囊菌门,其差异达极显著水平(p<0.01)。在属分类水平上,感病植株根际土壤真菌相对丰度增加的有赤霉菌属、丛赤壳属、镰刀菌属、假裸囊菌属和肉座菌属,其差异均达极显著水平(p<0.01);相对丰度降低的有未分类伞菌纲、枝鼻菌属、粗糙孔菌属、线虫草属、支顶孢属、粪盘菌属、木霉属和被孢霉属,其差异均达极显著水平(p<0.01)。猕猴桃感染根腐病后,根际土壤真菌在门和属水平上的菌群变化打破了原有的微生物拮抗平衡关系。

基于TRIZ的猕猴桃采摘机设计

针对猕猴桃采摘效率低、易损伤果实等问题,应用TRIZ理论指导猕猴桃采摘机的设计。通过需求分析,确定猕猴桃采摘机的作业流程。基于系统功能分析识别旋拧式猕猴桃采摘末端执行器的功能缺陷,应用因果分析、物场分析等TRIZ工具对采摘末端执行器求解创新方案,创新设计出一种自动定位果树—识别果实—剪断果梗—收集果实的猕猴桃采摘机。应用ADAMS对末端执行器采摘动作进行步态仿真、应用MATLAB对采摘机作业空间和采摘轨迹进行动态仿真,结果表明:猕猴桃采摘机采摘轨迹空间范围为X方向行程约1.4 m、Y方向行程约1.8 m和Z方向行程约2.3 m;采摘速度为8 s/个,末端执行器采摘过程作业动作平稳连贯,满足预期设计要求。在产品概念设计阶段应用TRIZ理论,有利于产生高质量、多层级的概念解,提高产品设计效率。

基于超高压处理的猕猴桃原浆制备研究

为优化猕猴桃超高压灭菌条件下原浆制作工艺,对3种不同原浆制作工艺分别进行单因素优化试验,筛选出两种产品色泽和稳定性较好的工艺,并对这两种工艺所制作样品进行4℃储藏40 d的品质对比。结果表明,在最大程度保留猕猴桃原浆绿色,提高其稳定性的条件下,3种工艺的优选次序为:对辊式挤压制浆>胶体磨制浆>高压微射流制浆;与胶体磨工艺相比,对辊式挤压工艺制作的产品在4℃条件下储藏30 d内无明显的自然分层,产品VC损失较少;优化后的制浆工艺为:采用对辊式挤压工艺,挤压次数为1次。按照该工艺制作的猕猴桃原浆色泽相对均一,以青绿色为主,VC含量为40~50 mg/100 g。

不同叶面肥及株型控制对中科猕砧2号猕猴桃组培苗生长发育的影响

以中科猕砧2号猕猴桃2月龄组培苗为研究对象,研究不同配比的叶面施肥结合株型控制对植株干径生长、叶绿素含量、氮磷钾含量以及幼苗生理指标的影响。结果表明,中科猕砧2号组培穴盘苗的干径、叶绿素含量及植株全氮、全钾含量,根冠比在不同处理间均存在显著差异,植株全磷含量在各处理间差异不显著。4个控制因子中,株型控制对中科猕砧2号组培穴盘苗生长的促进作用最大,全抹芽的株型控制+施复合叶面肥(0.2%尿素+0.1%磷酸二氢钾+0.2%园艺肥)为中科猕砧2号组培穴盘苗育苗期间的最优处理配方。

基于SWOT分析的陕西省周至县猕猴桃产业经济效益提升策略

为了助力陕西省周至县猕猴桃产业的持续健康发展,立足于周至县猕猴桃产业发展现状,采用SWOT分析方法梳理产业发展的影响因素,找出其中的症结和痛点。研究发现,周至县猕猴桃产业尚未形成规模化生产,果品质量无法得到有效保障,落后的组织经营方式严重影响了周至县猕猴桃产业的综合竞争力。为提升当地猕猴桃产业的经济效益,应强化政策引导,推动周至县猕猴桃产业标准化生产,重点培育具有品牌影响力的市场经营主体,利用电商平台做好品牌推广。

陕西省周至县猕猴桃产业循环经济发展模式

以陕西省周至县猕猴桃产业作为研究对象,分析了周至县猕猴桃产业发展现状及面临挑战,从生产加工、运输与销售、废弃物循环处置及生态产业园区构建等方面为周至县猕猴桃产业循环经济发展模式提供思路,希望能够进一步助力周至县猕猴桃产业大循环发展。

基于层次分析法的陕西眉县、周至县猕猴桃产业发展研究

为进一步提高猕猴桃产业发展水平,以陕西省眉县及周至县为研究对象,采用层次分析法,对地区猕猴桃产业发展及影响因素进行了实证研究。结果表明,眉县及周至县猕猴桃产业发展处于中等偏下水平,综合得分为5.25分;在主要影响地区猕猴桃产业发展的4个因素中,营销因素影响权重的占比最大为0.49,但问卷得分却相对较低,营销渠道单一、推广方式老旧、营销策略缺乏创新是产业在营销过程中面临的主要问题;政策因素虽然在产业发展中影响权重排行第二,但二级指标的平均得分只有5.26,政策实施效果相对不明显,还有较大提升空间;在市场及资源因素中,眉县及周至县猕猴桃也存在对消费者偏好把握不够精准、技术利用率低等问题,阻碍了产业的进一步发展。提高眉县及周至县猕猴桃产业发展水平,应从拓展营销渠道,加强品牌建设,结合地区生产实践,提升相关政策实施水平,优化产业布局,积极引进新优品种等方面进行提升优化。

桃胶和竹醋涂膜对猕猴桃果实采后软化机理研究

为探究桃胶和竹醋涂膜处理对猕猴桃采后果实软化的作用机理。以‘翠玉’猕猴桃为试材,采用2%桃胶、0.5%竹醋及桃胶+竹醋复合涂膜处理浸泡3 min,置于(5±1)℃、湿度为90%~95%的冷库中贮藏,研究果实硬度、细胞壁组分、软化相关酶活性及其基因表达量的变化规律。结果表明,复合涂膜处理显著抑制多聚半乳糖醛酸酶(PG)、β-半乳糖苷酶(β-Gal)、纤维素酶(Cx)和果胶酯酶(PE)的活性,降低PG、β-Gal、Cx和PE基因的表达,有效抑制细胞壁骨架物质、原果胶和纤维素的降解,延缓可溶性总糖和可溶性蛋白含量的上升,从而维持果实的硬度,延迟果实后熟软化。综上,桃胶和竹醋复合涂膜保鲜效果优于单一处理,是延缓猕猴桃果实细胞壁代谢和保持果实品质的有效措施。