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1.
白肉枇杷多酚氧化酶酶学特性研究   总被引:1,自引:1,他引:0  
以“白梨”枇杷 (Eriobotrya japonica Lindl.cv.Baili)果实为试材,采用硫酸铵分级盐析及透析法提取PPO研究其理化特性,包括温度、pH、抑制物对PPO活性的影响及其底物特性;测定果实\贮藏期间pH值变化。结果表明:PPO的最适温度为30~40℃,在30℃有较好的热稳定性;最适pH值为5.0和7.0,pH值为6.0和9.0时酶的稳定性较好;维生素C和L-半胱氨酸抑制物对PPO有较强的抑制作用,以维生素C抑制作用最强。  相似文献   

2.
对布朗李炭疽病菌[Glomerella cingulata (Stonem) Spaulding et Schrenk] 生物学特性研究表明:该菌菌丝生长与子囊果和子囊孢子形成最佳培养基为PSA+1‰酵母膏。病菌能有效地利用各种碳源,氮源以脯氨酸最好。菌丝生长的温度范围为15~30℃,最适为20~25℃;pH值范围为2~11,最适pH 6~8。子囊果和子囊孢子形成最适温度和最适pH值分别为25℃和7~8。分生孢子形成和萌发最适温度分别为25~30℃和20~30℃;最适pH值分别为6~8和7~9。分生孢子在饱  相似文献   

3.
dxqxq@sohu.com     
 对布朗李炭疽病菌[Glomerella cingulata (Stonem) Spaulding et Schrenk] 生物学特性研究表明:该菌菌丝生长与子囊果和子囊孢子形成最佳培养基为PSA+1‰酵母膏。病菌能有效地利用各种碳源,氮源以脯氨酸最好。菌丝生长的温度范围为15~30℃,最适为20~25℃;pH值范围为2~11,最适pH 6~8。子囊果和子囊孢子形成最适温度和最适pH值分别为25℃和7~8。分生孢子形成和萌发最适温度分别为25~30℃和20~30℃;最适pH值分别为6~8和7~9。分生孢子在饱  相似文献   

4.
芦荟黑斑病病原鉴定及培养特性的研究   总被引:3,自引:0,他引:3  
为进一步了解芦荟黑斑病的发生规律,采用组织分离法、血球计数板法、悬滴法等对病原菌进行了形态鉴定及其培养特性的研究。结果表明,芦荟黑斑病的病原菌为倒梨形链格孢(Alternaria obpyriformisT Y Zhang)。该菌菌丝生长和分生孢子产生的温度范围为10~30℃,最适温度为25℃;在pH 3.92~10.82的范围内该菌均能生长和产孢,菌丝生长最适pH 3.92~6.83,产生分生孢子的最适pH 5.23~6.83;分生孢子萌发的温度范围为10~35℃,最适20~30℃,最适pH 3.86~9.23。分生孢子在饱和湿度或水滴中萌发快,相对湿度低于81%时不能萌发。分生孢子的致死温度为55℃,10 min。光暗交替下培养的菌丝生长最好,产孢量最多,其次是完全黑暗下,而连续光照条件下的菌丝生长缓慢且产孢量少。该菌适合在含有芦荟成分的培养基上生长和产孢,能利用多种单糖、多糖及醇类作碳源和L-亮氨酸等有机氮和硫酸铵等无机氮作氮源。  相似文献   

5.
魔芋灰霉病致病菌及其生理特性的研究   总被引:3,自引:2,他引:1  
为探明魔芋灰霉病的发病规律,对其发病症状、致病菌及其生理特性进行了较系统的研究。结果表明,魔芋灰霉病菌为葡萄孢菌属(Botryotinia);其分生孢子萌发的温度范围为10~30℃,最适温度为20~25℃;在pH 4~9条件下均能萌发,最适pH为5;在各种营养液中均能萌发,在2%的蔗糖液中萌发最好,其次为2%的葡萄糖和魔芋甘露低聚糖;分生孢子的致死温度为57℃、5 min。魔芋灰霉病菌菌丝在4种培养基上均能生长,其中PDA培养基最适宜菌丝生长,最适的产孢培养基为PDA+魔芋甘露低聚糖;菌丝在5~30℃均能生长和产孢,适宜温度为20~25℃;在pH 4~9均能生长及产孢,最适pH为5。  相似文献   

6.
研究温度、光照、紫外辐射、蛋白酶K、pH对生防菌短短芽孢杆菌(Brevibacillus brevis)JK-2胞外物质抗香蕉枯萎病菌稳定性的影响,为香蕉枯萎病生防菌剂的研制提供理论依据。在30℃,170r/min的条件下,恒温振荡培养36h采样制备生防菌短短芽孢杆菌(Brevibacillus brevis)JK-2胞外物质,以香蕉枯萎病菌为指示菌,对胞外物质的抑菌特性进行研究。结果表明:该胞外物质具有一定的热稳定性,60~80℃温育1h保持88.5%以上活性,在100℃放置1h后无抑菌活性;在酸性pH3.0~5.0和碱性pH9.0~11.0条件下,抑菌活性保持在77.2%以上,对光照、蛋白酶K、紫外照射均不敏感。其抑菌作用的最适温度为30℃,最适pH为7.0。  相似文献   

7.
薛润光  杨少华  赵菊  郭承刚  罗洁 《种子》2006,25(7):76-77
通过发芽试验,研究了温度、光照、pH值、覆土厚度和贮藏时间对青洋参种子萌发的影响。结果表明:青洋参种子最适宜萌发温度在20~25℃之间;种子对光的敏感性不强,无光照比全光照的发芽率和发芽势高;对pH值的适应范围很宽,pH值为2~10范围内均可萌发;种子最适覆土厚度为2 cm;最适贮藏时间为12个月。  相似文献   

8.
为了研究超高压和pH值单独及协同处理对哈密瓜中脂氧合酶(LOX)的钝化效果,采用柠檬酸和碳酸钠调整哈密瓜汁的pH值为2~11,设定实验压0.1~500MPa,温度20~60℃,保压时间0~40min。结果表明,哈密瓜中LOX的最适pH值为7~8,最适温度为30~35℃;常温下单纯超高压处理鲜榨哈密瓜汁很难钝化LOX,调整酸碱度协同超高压处理,能很好地钝化LOX;在pH值4~5,温度25℃和55℃,压力300~500MPa,保压时间5~30min时,LOX的钝化符合一级反应动力学。  相似文献   

9.
对茭白胡麻斑病生物学特性进行了研究,结果表明:该菌菌丝生长的适宜温度10~35℃,最适温度25℃;分生孢子产生的适宜温度10~30℃,最适温度25℃;分生孢子致死温度为56℃;该菌菌丝生长和分生孢子产生的pH值3~12,最适pH值6~9,中性偏碱的条件下有利于分生孢子的形成;该菌菌丝生长最适碳源为乳糖,而产孢最适碳源为果糖;氮源酵母膏促进菌丝生长,酵母膏和氯化铵能促进产孢,牛肉膏和硝酸钾不利于产孢。  相似文献   

10.
橄榄小孢拟盘多毛孢(Pestalotiopsis microspora)是导致采后橄榄果实腐烂的主要病原菌,本文研究了pH、温度、光照、碳源、氮源等条件对橄榄小孢拟盘多毛孢菌落生长、产孢和分生孢子萌发的影响。结果表明,橄榄小孢拟盘多毛孢生长最适pH为6,最适温度24~26℃;产孢最适pH为7,最适温度24~26℃,光暗交替条件下产孢量最多;以D-果糖、甘露醇为碳源和以蛋白胨为氮源的培养基最有利于橄榄小孢拟盘多毛孢菌丝的生长,以葡萄糖、蔗糖为碳源和以蛋白胨为氮源的培养基最有利于该菌产孢;分生孢子萌发最适pH为6,最适温度26~28℃,全黑暗条件下孢子萌发率最高;该菌菌丝致死温度为54℃(30 min),分生孢子致死温度为56℃(20 min)。  相似文献   

11.
Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.  相似文献   

12.
Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.  相似文献   

13.
Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.  相似文献   

14.
G. H. Kroon 《Euphytica》1994,76(1-2):125-125
Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.  相似文献   

15.
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...  相似文献   

16.
Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.  相似文献   

17.
P. A. York  R. Cook 《Euphytica》1989,43(1-2):135-141
Summary Reactions of 13 grasses to Meloidogyne naasi varied with species; ryegrasses, fescues and their hybrids were generally susceptible and cocksfoot and timothy resistant. Marked variation in host resistance levels occurred between genotypes within cultivars.Selection of single plants, followed by tests on replicate tillers, identified resistant and susceptible genotypes in both Italian and perennial ryegrass cultivars. Resistant plants had few nematode-induced galls and fewer females and eggs than susceptibles. There was more or less continuous variation, with many genotypes intermediate between extremes of resistance and susceptibility. Selected resistant and susceptible genotypes are of use in assessing variation in nematode populations and as controls for breeding and selection programmes.  相似文献   

18.
Lentil production is limited by lack of moisture and unfavorable temperatures throughout its distribution. Waterlogging and salinity are only locally important. Progress has been made in breeding for tolerance to drought through selection for an appropriate phenology and increased water use efficiency and in breeding for winter hardiness through selection for cold tolerance.The diseases rust, vascular wilt, and Ascochyta blight, caused by Uromyces viciae-fabae, Fusarium oxysporum f. sp. lentis, and Ascochyta fabae f. sp. lentis, respectively, are the key fungal pathogens of lentil. Cultivars with resistance to rust and Ascochyta blight have been released in several countries and resistant sources to vascular wilt are being exploited. Sources of resistance to several other fungal and viral diseases of regional importance are known. In contrast, although the pea leaf weevil (Sitona spp.) and the parasitic weed broomrape (Orobanche spp.), and to a lesser extent the cyst nematode (Heterodera ciceri), are significant yield reducers of lentil, no sources of resistance to these biotic stresses have been found. Directions for future research in lentil on both biotic and abiotic stresses are discussed.  相似文献   

19.
Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.  相似文献   

20.
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...  相似文献   

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