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1.
采用比色法测定了以朱砂根(Ardisia crenata)胚、根、茎及叶等4种外植体诱导的愈伤组织中皂苷含量,筛选高皂苷含量的愈伤组织。结果表明,朱砂根的胚和根诱导出来的愈伤组织皂苷含量最高,达到24.07 mg/g和21.25 mg/g,茎和叶诱导的愈伤组织皂苷含量较低,根和茎诱导的愈伤组织生长较好。  相似文献   
2.
We compared patterns of acorn dispersal and predation by wood mice among four tree species (Quercus serrata, Quercus crispula, Castanea crenata, and Juglans mandshurica var. sieboldiana) that are abundant in cool temperate woodlands. We devised an acorn dispersal experiment using 400 magnet-inserted acorns and a magnetic locator in a 1.8-ha study plot, which spanned a cut-over area and an adjacent deciduous forest. Ten wire mesh baskets, each containing 40 acorns (10 acorns per species), were placed on the border between these two habitat types. About 13.0% (n = 52) of the total acorns remained in the baskets, while 77.3% (n = 309) were dispersed throughout the study plot and subsequently retrieved using the magnetic locator. Microhabitat, distance, and burial depth of transported acorns were significantly different among species. In the cut-over area, J. mandshurica var. sieboldiana acorns were dispersed under fallen trees or branches and near stumps, and were buried deeply in the soil. Dispersal distances of J. mandshurica var. sieboldiana acorns were significantly greater than those of Q. serrata acorns. The number and microhabitat of transported acorns significantly differed between habitat types. J. mandshurica var. sieboldiana acorns were dispersed in the cut-over area rather than in the forest. For all four species, the numbers of acorns delivered to fallen trees or branches, stumps, and crumbled soil with overhang under any vegetation type were greater in the cut-over area than in the forest.  相似文献   
3.
Six populations of faba bean (Vicia faba L.) were developed through various selection schemes to examine the influence of selection In improving tolerance to Orobanche crenata (Forsk.) in local faba bean stocks. All populations trace their origin to 209 farmers’ seed lots that were collected from Egypt. The entries of each population were grown during the 1982/1983 season in the Orobanche nursery located at Giza in Egypt. Comparison among means of the selected, populations showed that more progress in improving Orobanche tolerance could be achieved from combined selection between and within lots. Between-lots selection was less efficient than single-plant selection. Results, of this study show that considerable progress could be achieved from selection for Orobanche tolerance in local faba bean germplasm. There was sufficient residual genetic variation in the selected populations to expect substantial progress from further selection for most tolerance traits.  相似文献   
4.
朱砂根外植体消毒及启动培养的研究   总被引:1,自引:0,他引:1  
以朱砂根优良单株为材料,进行朱砂根外植体表面消毒及启动培养研究,从外植体材料、消毒试剂、消毒流程以及启动培养的基本培养基、植物激素等因素进行试验,通过完全随机试验设计和正交试验设计优化出最佳的外体植消毒流程和启动培养的培养基组合。结果表明,带腋芽茎段外植体的最佳消毒流程是先用75%乙醇消毒50~60 s,再用0.1%Hg Cl2溶液灭菌7 min,其污染率控制在28.9%,成活率达66.7%;朱砂根启动培养的培养基最佳组合为改良MS+6-BA 3.0 mg/L+NAA 0.1 mg/L。该研究结果为朱砂根的组培工厂化育苗奠定重要基础。  相似文献   
5.
Parasitic plants infest numerous plants throughout the world depleting them of nutrients, minerals and water. Orobanche species are chlorophyll-lacking root holoparasites that cause severe damage to broad-leaved crops. Orobanche aegyptiaca and Orobanche crenata parasitize field, vegetable, fodder, flower and herb crops in the Mediterranean region. Curled parsley (Petroselinum crispum), a major crop in the dry herb industry in Israel, is highly susceptible to O. aegyptiaca and O. crenata and in infested fields suffers severe yield and quality damage. An in vitro study in polyethylene bags, greenhouse experiments in soil-filled pots and trials in a naturally Orobanche-infested field were performed in order to screen and test for differential susceptibility of parsley varieties to O. aegyptiaca and O. crenata. Results revealed that the parsley varieties Garland and Garbo were tolerant to Orobanche compared to the susceptible varieties Darki, Extra Triple and Kaderava.  相似文献   
6.
保湿方法对金叶龟甲冬青扦插生根的影响   总被引:1,自引:0,他引:1  
通过田间试验研究2种不同保湿方法对金叶龟甲冬青扦插生根的影响,筛选出最适合的扦插保湿方法。结果表明:用塑料杯覆盖处理金叶龟甲冬青,其扦插成活率、插条生根数、平均根长均有所提高,其中生根率达到了90.3%,生根数达到了16,平均根长达到了11.2 cm,均达到了极显著水平;生根所需时间3种处理无显著差异。金叶龟甲冬青嫩枝扦插繁殖,使用覆盖塑料杯的保湿方法较为适宜。  相似文献   
7.
陈坚 《林业科技开发》2012,26(3):122-124
以朱砂根及其变种红凉伞为试验材料,研究了大田栽培方式下,朱砂根及其变种红凉伞在上海地区的生长习性和物候期表现,观测和记录朱砂根各时期花芽形态特征,研究了朱砂根在上海地区花芽分化过程。结果表明:大田栽培下,朱砂根的萌芽、开花和坐果等物候期都比其变种红凉伞晚,但它们的各物候期持续时间一致。通过对大田栽培的朱砂根花芽分化期观察,认为朱砂根在上海地区花芽能够正常分化,花器官能够正常分化和发育,分化时期为4—5月。  相似文献   
8.
朱砂根枯萎病的发生特点与防治技术   总被引:1,自引:0,他引:1  
朱砂根近几年作为观果花卉连年设施栽培,导致枯萎病发生日益严重。经作者多年试验探讨,总结了朱砂根枯萎病发生的症状、病原菌、病害发生规律及其影响因素,并提出相应的综合防治措施。这是我国南方对朱砂根枯萎病的首次报道。  相似文献   
9.
楼晓明  沈杰  楼兵干  李柱 《植物保护》2008,34(6):109-112
于2002-2005年连续3年观察了杭州龟甲冬青枝枯病的症状,该病害先在嫩枝枝条发病,病斑初为水渍状斑点,后扩大成暗褐色的不规则形病斑。从发病部位分离培养出病原菌,根据其分生孢子的形态、大小和核糖体DNA内转录间隔区的序列,鉴定为褐纹拟茎点霉[Phomopsis vexans (Sacc.et Syd.) Harter]。本文对该病害症状和病原形态特征进行了描述。  相似文献   
10.
栽培种源朱砂根播种育苗及其影响因子的研究   总被引:1,自引:0,他引:1  
比较了播种时期、播种方式和外源激素浸种处理对栽培种源朱砂根幼苗生长、发育和品质的影响.结果表明:朱砂根在2月底至3月下旬期间播种,出苗率高,幼苗胚根粗,胚根长;不同播种方式中,叶龄、茎长、主根长、全株干重、根冠比各项指标排序依次为地播苗>营养袋苗>穴盘苗;NAA浸种能促进朱砂根幼苗茎及主根的生长,适当浓度的GA3浸种对增进叶龄有效,其中,10ng/L NAA、20 mg/L NAA、50mg/L GA3浸种效果最好;而IBA浸种不促进幼苗生长.  相似文献   
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