Southwest China is one of the most concentrated regions of wild kiwifruit germplasm. With the increased instances of extreme weather and the impact of human activities, the wild kiwifruit population is being destroyed. However, there is little research on the wild kiwifruit resources. Therefore, strengthening research on wild resources of kiwifruit and determining the genetic diversity of kiwifruit are essential. In this study, 110 wild kiwifruit germplasms were collected as test materials. We selected 13 primers out of 256 pairs to analyze the genetic diversity. A total of 178 loci were amplified, including 175 polymorphic loci, accounting for 98.31%. The genetic similarity coefficient ranged from 0.551 to 0.905, with an average of 0.721. The effective allele number (Ne), Nei’s gene diversity index (H) and Shannon’s information index (I) were 1.452, 0.245 and 0.439, respectively. Very low genetic differentiation (Gst: 0.051) and very high gene flow (Nm: 11.899) were observed. When the genetic similarity coefficient was 0.652, the kiwifruit germplasms were divided into four categories, and the geographical distribution of samples in different categories was inconsistent. The result of principal coordinate analysis (PCoA) and structure analysis showed that the population of wild kiwifruit was divided into two subgroups. Our research contributed to identifying the genetic background of wild kiwifruits in Guizhou Province, China, and can be an important reference for the protection of wild kiwifruit and the breeding of new kiwifruit varieties.

Diaporthe spp. (including their asexual Phomopsis states) are important plant pathogens found widely in different host plants, such as pathogens, endophytes or saprobes. In this study, a new species of Diaporthe causing fruit rot in kiwifruit, Diaporthe xiuwenensis sp. nov was isolated from kiwifruit with apparent soft rot symptoms during storage in Guizhou Province, China. Identification was made using morphology and comparison of DNA sequence data of the nuclear ribosomal ITS (internal transcribed spacer) + tef1 (translation elongation factor-1 alpha) + tub2 (beta-tubulin) + cal (calmodulin) + his (histone H3) gene regions. This study further described a new Diaporthe species and discussed its morphology and phylogenetic relationships with other Diaporthe species. Koch's postulates tests identified the causative agents of kiwifruit soft rot. The results of pathogenicity test showed that Diaporthe xiuwenensis sp. nov was pathogenic to kiwifruit, and the Koch's postulates were completed.

Kiwifruit canker and brown spot are significant diseases affecting kiwis, caused by Pseudomonas syringae pathogenic 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 nature 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 disease-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.

【Objective】To understand the effects of different disease resistance inducers on the field control effect, leaf nutrient content, fruit yield and quality of kiwi brown spot, in order to screen out the best disease resistance inducers for the prevention and control of kiwi brown spot, and provide technical support for the green prevention and control of kiwi brown spot.【Method】Taking ‘Hongyang’ kiwifruit as the research object, field experiments were carried out with single application and mixed application of different disease resistance inducers, and the incidence, disease index,control effect and leaf nutrient content of brown spot disease in the field were determined after the investigation, and the relevant indicators of the fruit were measured and comprehensively evaluated at the ripening stage.【Result】There were significant differences in the effect of different disease resistance inducers on the prevention and treatment of brown spot. Treatment 6（Artaine + Heyi Sea Star） had the best prevention and control effect, and its prevention and treatment effects were 52.72%, 78.39% and 73.28% in 10, 20 and 30 days after the medication, followed by the prevention and treatment effect of treatment 5（aminooligosaccharin + Heyi Sea Star）. Compared with CK（methyltobutazine）, the contents of nitrogen（N） and potassium（K） in leaves were increased by each treatment of disease resistance inducer in 10 days after treatment. The N content of leaves changed greatly in 10, 20 and 30 days after the medication, and the overall content showed a significant downward trend. Among them, the leaf N content of treatment 6（Artaeling + Heyi Sea Star） was the highest. The overall variation of K content in leaves in 10, 20 and 30 days after medication treatment was small. In 10 days after the medication, the K content of the leaves of treatment 5（aminooligosaccharin + Heyi Sea Star） was the highest. At 20 and 30 days after the medication, the K content of the leaves of treatment 6（Artaelin + Heyi Sea Star） was the highest. However, the inducer failed to effectively increase the phosphorus（P） content of leaves. The correlation analysis results showed that the N content of leaf was significantly negatively correlated with the incidence and disease index of brown spot, indicating that the disease resistance inducer mainly enhanced its disease resistance ability by inducing the absorption of leaf N pigment. The comprehensive evaluation results showed that treatment 5（aminooligosaccharin + Heyi Sea Star） had the best effect on fruit yield and quality, followed by treatment 6, CK had the worst improvement effect.【Conclusion】Treatment 5（aminooligosaccharin + Heyi Sea Star） had significant effects on immune induction, fruit yield and fruit quality improvement, and aminooligosaccharin + Heyi Sea Star could be used as the best disease resistance inducer in green control of kiwifruit brown spot.

通过对146份贵州猕猴桃种质资源表型遗传多样性的研究,为贵州猕猴桃品种选育打下基础,对146份不同区域猕猴桃种质资源48个质量性状进行描述、赋值,并结合单果重等9个数量性状,使用主成分分析、聚类分析等进行综合评价.结果表明,57个质量性状和数量性状均存在丰富的多样性和变异性;146份资源的Shannon's遗传多样性指数为1.28,从各区域遗传多样性指数可以看出,演化进程上从遗传多样性指数高的地区向低的地区进行演化;主成分分析结果显示,前14个主成分累计贡献率达75.076％,其中前6个主成分的累计贡献率达51.911％,为提高品种选育和评价的工作效率,可将猕猴桃种质资源的描述指标简化为新梢被毛、果实被毛等18个性状;聚类结果显示,贵州猕猴桃种质的欧氏距离为1.00～25.00之间,在D=19.25处,146份野生猕猴桃分为6个类群.本文有效揭示了贵州省猕猴桃种质资源丰富的多样性和亲缘关系,明确野生猕猴桃各种群间性状区分特征和部分优良资源性状的地理分布,对贵州猕猴桃种质资源的种质鉴定、保护利用和品种选育有重要意义.

本研究设置"红阳"猕猴桃果园鼠茅草种植小区和对照小区各10个,每月中旬进行杂草种类和覆盖度调查,并在鼠茅草死亡后测定种植小区和对照小区土壤养分,分析果园杂草动态变化、鼠茅草抑草效果及对土壤肥力的影响.结果表明,"红阳"猕猴桃果园杂草种类数和平均覆盖度全年变化均呈先增后减趋势,峰值在6-7月,杂草种类最多为22种,覆盖度最高可达100.0％,几乎全园覆盖;鼠茅草对杂草的最佳抑制率均在其倒伏后,其中,对杂草种类抑制率以6月最佳,达47.95％;对杂草覆盖度抑制率以5月最佳,达39.06％;种草后,土壤有机质、全氮、碱解氮、全磷、速效磷、全钾、速效钾均有所减低,分别降低了 7.68％、16.63％、8.56％、34.88％、36.70％、4.09％、20.26％,但仅全氮、全磷含量差异显著.种植鼠茅草抑制"红阳"猕猴桃果园杂草有一定作用,但会降低果园土壤肥力;与北方种植情况相比,试验园的鼠茅草生长期相对较短,杂草抑制率偏低.

为了明确红阳猕猴桃褐斑病主要病原菌及适宜的防治药剂,采集贵州省六盘水市水城区红阳猕猴桃褐斑病的标样,通过组织分离、纯化,致病性检测,形态学观察,分子检测及系统发育分析确定病原菌种类,并采用菌丝生长速率法测定6种药剂对该病原菌生长的抑菌效果.结果显示:分离纯化得到的病原菌的形态特征与多主棒孢菌Corynespora cassiicola形态特征相似,将分离菌株rDNA-ITS序列与GenBank中相关菌株的ITS序列进行同源性比对,发现该菌株与黄瓜多主棒孢霉菌的相似性达到96％以上.室内药剂筛选结果表明:50％多菌灵可湿性粉剂对病原菌的抑制效果最好,最低浓度可抑制菌丝生长;其次为40％戊唑醇悬浮剂、80％乙蒜素乳油、30％吡唑嘧菌酯乳油和80％代森锰锌可湿性粉剂,抑菌效果较好,EC50值分别为0.000 2、0.074 3、0.087 1、和0.502 5 mg/L.红阳猕猴桃褐斑病主要由多主棒孢菌Corynespora cassiicola侵染引起,以上5种药剂均可作为防治红阳猕猴桃褐斑病的有效药剂.

[目的]探究猕猴桃苗不同生长时期根际土壤细菌群落组成及土壤养分间的相互关系.[方法]采用Illumina-MiSeq高通量测序研究猕猴桃苗不同生长阶段(生长前期、速生期、生长后期)的根际微生物群落结构组成及其多样性.运用CANOCO和R语言软件对土壤细菌群落与土壤环境因子间关系进行RDA和相关性热图分析.[结果]随着猕猴桃苗不断生长,土壤pH、速效N、速效P均出现先升高后降低趋势,速效K则随着猕猴桃苗生长逐渐降低;高通量测序共得到25 822个细菌OTUs,分属于28门53 纲 172 科 226 属,其中变形菌门(Proteobacteria,35.84％)、酸杆菌门(Acidobacteria,17.69％)、放线菌门(Actinobacteria,12.6％)是猕猴桃苗不同生长时期土壤的优势菌门;土壤细菌群落多样性指数和丰富度指数在猕猴桃生长初期与速生期和生长后期有显著差异;不同生长时期相对丰富度大于1％的菌门中,Cyanobacteria随着猕猴桃苗不断生长而逐渐减少,Actinobacteria、Latescibacte-ria、Acidobacteria的相对含量先升高后降低.[结论]猕猴桃苗根际土壤细菌群落组成和根际土壤养分发生变化受猕猴桃苗不同生长时期的影响,土壤根际主要养分和pH是影响土壤根际细菌群落结构比例变化的重要因子.

为探究猕猴桃苗不同生长期与根际土壤真菌群落结构、多样性及土壤养分之间的相互关系,利用Illumina MiSeq高通量测序研究猕猴桃苗3个不同生长阶段(生长前期、速生期、生长后期)根际微生物群落结构组成及其多样性,运用CANOCO和R语言软件对土壤真菌群落与土壤环境因子间关系进行RDA和相关性分析.结果表明:猕猴桃苗不同生长期土壤性质均存在显著差异,随着猕猴桃苗根系不断生长,土壤pH、速效氮、有效磷出现先升高后降低趋势,速效钾则出现先降低后升高;高通量测序共得到1 776个真菌OTUs,分属于10门22纲151科157属;方差分析表明各生长时期多样性指数(Shannon)差异显著;序列分析发现,子囊菌门(Ascomycota,丰度72.69％)、被孢霉门(Mortierellomycota,18.80％)、罗兹菌门(Rozellomycota,6.68％)、担子菌门(Basidiomycota,4.28％)和球囊菌门(Glomeromycota,1.45％)是猕猴桃苗不同生长期的优势菌门(丰度大于1％的视为优势菌门);对不同生长时期优势菌门所占比例进行分析,发现子囊菌门出现先升高后降低,被孢霉门、罗兹菌门和担子菌门则出现先降低后升高,球囊菌门相对丰度随着猕猴桃根系生长逐渐升高;RDA分析结果显示,有效磷和pH与子囊菌门显著正相关,速效钾与子囊菌门显著负相关,有机碳与壶菌门(Chytridiomycota)显著负相关.综上,猕猴桃苗在不同生长时期根际土壤真菌群落结构不同,速生期根际真菌种群最丰富,生长后期最少;子囊菌门、被孢霉门、罗兹菌门和担子菌门始终是猕猴桃苗生长期根际优势菌群;根际真菌群落组成和土壤养分变化受猕猴桃苗不同生长时期的影响,其中土壤有效磷和速效钾是影响子囊菌门群落组成的重要因子.

为明确贵州省猕猴桃主栽品种果实腐烂病病原菌的种类,并为田间果实病害防治提供理论依据,以2018—2019年在贵州省水城县和修文县两大主产区采集的红阳和贵长猕猴桃病果为试验材料,通过病原菌的分离、形态学观察、分子检测和致病性检测,研究病果中病原真菌的种类,并对其序列进行系统发育分析.结果表明,分离到4类病原菌:拟茎点霉菌(Phomopsis cauloides)、镰刀菌(Fusarium)、交链格孢菌(Alternaria alternata)、黄瓜织球壳菌(Plectosphaerella cucumerina),其检出率分别为10％、60％、20％、10％.其中,黄瓜织球壳菌侵染引起猕猴桃果实病害在国内尚属首次报道.

[目的]筛选能促进猕猴桃生长和提高果实品质的最佳处理,为猕猴桃合理施肥提供参考.[方法]以'红阳'Actinidia chinensis'Hongyang'猕猴桃为试材,于壮果期,采用沟施方式,在施用复合肥的基础上,增施有机肥和菌肥,测定和统计各处理下猕猴桃果实的外观性状、内在品质及果实采后软腐病发生率.[结果]与对照相比,增施有机肥和菌肥后,猕猴桃果实的横纵径、果形指数无显著差异,各处理的单果质量不同程度有所增加,但与对照均无显著差异.其中复合肥、海藻甲壳素混施处理(处理2)中猕猴桃单果质量增加幅度最大,较对照增加了23.82％.增施有机肥和菌肥处理对果实中微量元素含量的影响显著.增施有机肥和菌肥后,除硼含量外,果实中其他元素含量均显著高于对照.其中,复合肥、菌肥、黄腐酸钾、海藻甲壳素混施处理(处理6)中果实钙和锌含量高于其他处理及对照,分别比对照显著增加了5.07％与5.44％;果实中锰含量最高的是复合肥、菌肥、黄腐酸钾混施处理(处理4),镁含量最高的是处理2,分别比对照显著增加了62.16％与72.13％.增施有机肥和菌肥后,果实的可溶性固形物含量、可溶性糖含量、可溶性蛋白含量和糖酸比均高于对照,维生素C含量除了处理2,其余处理均高于对照,处理6的果实维生素C含量最高,菌肥、黄腐酸钾、海藻甲壳素混施处理(处理5)次之,分别较对照高出26.86％和24.21％.增施有机肥和菌肥后,果实软腐病发病率均比对照低,且差异显著.处理6的发病率最低,较对照低41.07％.[结论]在施用复合肥的基础上,增施有机肥和菌肥可较好地改善猕猴桃果实的外观性状和内在品质,并减少果实病害发生,以复合肥、菌肥、黄腐酸钾、海藻甲壳素混施的增质效果最好.

猕猴桃褐斑病是猕猴桃叶部主要病害,也可以发生于果实上,严重时可以引起果园叶片大面积提早脱落,大量秋稍萌发,对猕猴桃的产量和品质造成一定影响.根据近几年国内外报道,对猕猴桃褐斑病的发病症状、病原及寄主,发生规律及防治进行简要综述,并展望了猕猴桃褐斑病的研究方向.

随着社会的不断进步,国际间贸易的日益往来,外来入侵物种的数量呈现出逐渐增加的趋势.生物入侵已经成为生态安全研究中的主要内容.本文综合了近几年国内外生物入侵的发展情况,阐述了生物入侵的概念、方式、原因以及对入侵区产生的危害,同时总结了加强防治生物入侵的方法,以期对今后生物入侵的研究奠定一定的理论基础.

为了探讨不同砂土类型和不同埋藏方法对猕猴桃种子萌发及幼苗生长的影响,以梵净山野生猕猴桃种子为供试材料,研究了不同处理对猕猴桃种子萌发率、出苗率以及幼苗生长的影响.结果 表明:石英砂与腐殖土混合的砂土最适合猕猴桃种子萌发,平均萌发率达到84％,室内埋藏后的种子更有利于种子出苗,出苗率达到81.6％.方差分析结果表明不同砂土类型和不同埋藏方法对种子萌发率和出苗率均显著影响,该研究结果为猕猴桃种子资源保存和种苗繁育提供了理论依据.