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71.
Eun Ju Cho Do Jin Lee Chi Do Wee Hong Lim Kim Yong Hwa Cheong Ju Sik Cho Bo Kyoon Sohn 《Scientia Horticulturae》2009,122(4):633-637
We aimed to investigate the effects of inoculating Panax ginseng C.A. Meyer seedlings with arbuscular mycorrhizal fungi (AMF) by examining the root colonization, plant nutrition uptake, growth characteristics, and soil aggregation of P. ginseng seedlings inoculated at the time of transplantation. At 16 weeks, the AMF spore density per 30 g of fresh mycorrhizosphere in seedlings inoculated with AMF (AMF+ seedlings) was 256.8 and that in seedlings not inoculated with AMF (AMF− seedlings) was 186.3, respectively. The colonization rate of AMF in the lateral roots of AMF+ seedlings was approximately 19% higher than that in the lateral roots of AMF− seedlings. The patterns of AMF colonization in ginseng roots were similar to those of the Paris-type mycorrhizal association. Plant growth characteristics, such as plant height, root length, leaf area, number of lateral roots, fresh weight of shoots and roots, and chlorophyll content, were significantly enhanced in AMF+ seedlings compared to AMF− seedlings. The macronutrient content (P, K, and Ca) and micronutrient content (Cu, Fe, and Zn) of both shoots and roots were also significantly higher in AMF+ seedlings compared to AMF− seedlings. Furthermore, glomalin content and soil aggregation were significantly enhanced in AMF inoculated areas. Our results indicate that AMF inoculation may enhance the growth of ginseng seedlings by improving the uptake of mineral nutrients and the soil structure in mycorrhizosphere. 相似文献
72.
混合接种菌根真菌对喜树幼苗生长及喜树碱含量的影响 总被引:1,自引:0,他引:1
通过温室盆栽接种试验,研究了蜜色无梗囊霉(Acaulospora mellea)、弯丝硬囊霉(Sclerocystic sinosa)及二者混合接种(分别记为Am、Ss和Am-Ss)对喜树幼苗生长及喜树碱含量的影响.结果表明:丛枝菌根的形成促进了喜树幼苗的生长,菌根幼苗的生物量优于无菌根幼苗,混合接种Am-Ss的菌根幼苗显著高于无菌根幼苗和单接种的菌根幼苗.丛枝菌根形成影响了喜树幼苗的喜树碱代谢,菌根幼苗根、叶片和全株的喜树碱含量均显著高于无菌根幼苗,并且混合接种处理的喜树幼苗喜树碱含量最高. 相似文献
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为了使农业结构调整更加有的放矢,保持济南早春设施甜瓜高效、迅速的发展势头,从品种选择、保护地设施类型、育苗、定植、植株调整、肥水管理、病虫害防治等多方面介绍早春保护地薄皮甜瓜高效栽培技术,希望对提高甜瓜产量和品质以及菜农的经济效益能起到一定的指导作用。 相似文献
76.
为了解新疆天山野果林中塞威士苹果Malus sieversii与其林下伴生植物短距凤仙花Impatiens brachycentra两种植物叶斑病病原菌的多样性及同源性,采用组织分离法获得病原菌,基于rDNA-ITS序列构建系统发育树,并进行ITS序列BLAST同源性比对,对病原菌进行鉴定分类,并依据科赫氏法则测定致病性。结果显示,从新疆新源县天山野果林中的塞威士苹果及短距凤仙花病叶上共分离得到18株菌落形态各异的病原菌,分属于2属4种,绝大多数属于半知菌亚门。其中,链格孢属Alternaria sp.为塞威士苹果和短距凤仙花叶斑病病原真菌中的优势菌群。致病性测定结果显示,其中11株病原真菌对塞威士苹果具有致病性,7株病原真菌对短距凤仙花具有致病性;塞威士苹果所有的病原真菌对短距凤仙花均有致病性,而且短距凤仙花所有的病原真菌对塞威士苹果也有致病性。推测2种植物叶斑病可能由相同来源的病原真菌引发,短距凤仙花染病加剧了塞威士苹果叶斑病暴发,可能是野果林退化的重要原因。 相似文献
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【目的】明确7种生物药剂对百香果茎基腐病的防治效果,筛选高效安全生物药剂用于指导百香果生产。【方法】采用菌丝生长速率法测定7种生物药剂对百香果茎基腐病菌的毒力效果,观察药剂对病原菌孢子生长及形态的影响,并用离体接种法测定药剂的防治效果。【结果】7种生物药剂处理对菌落生长均有抑制作用,但对孢子的生长和形态的效果不同。室内毒力测试结果显示植物源药剂中抑菌效果最佳为井冈霉素(EC50为7.79 mg/L),其次为春雷霉素(EC50为26.35 mg/L)、乙蒜素(EC50为28.65 mg/L)、苦参碱(EC50为339.13 mg/L)和多抗霉素(EC50为1 150.29 mg/L)。微生物药剂以枯草芽孢杆菌效果较好,EC50为3.2×106 CFU/g。筛选毒力较强的4种生物药剂均可抑制百香果茎基腐病不同菌株生长。离体试验和田间防效试验表明井冈霉素和枯草芽孢杆菌生物药剂对百香果茎基腐病防治效果显著,两者的离体防效分别为58.8%和70... 相似文献
79.
采用生长速率法测定采自黑龙江省部分稻区的稻瘟病菌菌株对多菌灵的敏感性。试验结果表明,供试稻瘟病菌菌株抑制中浓度(EC50)大多数分布在200~300mg/kg之间,最高为405mg/kg,最低为158mg/kg,其EC50值相差2倍以上,说明供试稻瘟病菌对多菌灵的敏感性均较差,且供试菌株对多菌灵已产生不同程度的敏感性差异。 相似文献
80.
Response of spring wheat (Triticum aestivum) to interactions between Pseudomonas species and Glomus clarum NT4 总被引:1,自引:0,他引:1
The effects of interactions between pseudomonads (Pseudomonas cepacia strains R55 and R85, P. aeruginosa strain R80, P. fluorescens strain R92, and P. putida strain R104) and the arbuscular mycorrhizal fungus Glomus clarum (Nicol. and Schenck) isolate NT4, on spring wheat (Triticum aestivum L. cv. Laura), grown under gnotobiotic and nonsterile conditions, were investigated. Although plant growth responses varied,
positive responses to pseudomonad inoculants generally were obtained under gnotobiotic conditions. Shoot dry weight enhancement
ranged from 16 to 48%, whereas root enhancement ranged from 82 to 137%. Shoot growth in nonsterile soil, however, was unaffected
by pseudomonad inoculants, or reduced by as much as 24%. Shoot growth was unaffected or depressed by G. clarum NT4 whereas early root growth was enhanced by 38%. Significant interactions between the pseudomonad inoculants and G. clarum NT4 were detected. Typically, dual inoculation influenced the magnitude of response associated with any organism applied
alone. The effect of these pseudomonads on G. clarum NT4 spore germination was investigated. Germination was inhibited when spores were incubated either on membranes placed directly
on bacterial lawns of strains R85 and R104 (i.e., direct assay), or on agarose blocks separated from the bacteria by membranes
(i.e., diffusion assay). When the agarose blocks were physically separated from the pseudomonad (i.e., volatile assay), there
was no evidence of inhibition, suggesting that a nonvolatile, diffusible substance(s) produced by both strains R85 and R104
may inhibit G. clarum NT4 spore germination.
Received: 11 December 1995 相似文献