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81.
研究了10个不同地区Colletotrichum fructicola菌株群体遗传结构。145个病菌样品ITS序列可推导出13种单倍体型(haplotype),其中,Haplotype 5为优势单倍型,有127个菌株。湖北随州地理种群与其他种群遗传分化极大,遗传分化指数(FST)为0.14685–0.40385。AMOVA分析显示,种群间和种群内的遗传变异分别占总变异的13%和87%;Mantel测试显示地理距离与遗传分化没有显著的线性关系;该菌经历过种群扩张,群体间存在有效基因流。 相似文献
82.
芒果老叶在增强UV-B辐射处理下的损伤和保护反应 总被引:1,自引:0,他引:1
以‘台衣一号’芒果盆栽苗离体老叶为试材,研究增强UV—B辐射条件下芒果老叶的损伤和保护反应。结果表明:UV—B辐射处理使芒果叶片MDA含量和相对电导率升高、叶绿素含量和叶绿素a/b降低,表明叶片受到损伤,且随处理时间延长叶片损伤加重。UV—B辐射处理叶片可溶性蛋白含量、抗氧化酶(SOD、CAT、POD)活性、保护色素(类胡萝卜素、类黄酮)和还原型GSH含量显著高于对照叶片,UV—B辐射处理叶片维生素C含量显著低于对照叶片,表明增强UV—B辐射可诱导叶片细胞通过提高活性氧清除能力和积累保护色素而直接吸收部分UV—B辐射来提高抗增强UV—B辐射损伤的能力。 相似文献
83.
炭疽病是油茶Camellia oleifera的重要病害,该病害的优势致病菌是刺盘孢属Colletotrichum的果生刺盘孢C. fructicola,在全国的油茶产区普遍发生。我们前期发现组蛋白乙酰转移酶CfGcn5调控油茶果生刺盘孢的生长发育和致病过程,但组蛋白去乙酰化酶在该病菌中的生物学功能尚不清楚。本研究以组蛋白去乙酰化酶CfSnt2为研究对象,利用反向遗传学的方法,通过对野生型、CfSNT2基因敲除突变体及互补菌株的生物学表型进行比较分析,发现CfSNT2基因敲除突变体的菌丝生长速率明显减缓、分生孢子的产量显著减少、附着胞形成率降低、对细胞壁胁迫剂的响应异常,同时对油茶致病力显著减弱。以上现象说明CfSnt2调控果生刺盘孢的生长、产孢、附着胞的形成、对细胞壁完整性胁迫剂的耐受性及致病力。 相似文献
84.
杧果生物技术研究进展 总被引:1,自引:0,他引:1
从杧果组织培养、基因克隆、遗传转化及分子标记等几个方面概述了近年来杧果生物技术研究的进展. 相似文献
85.
86.
采后ABA、GA_3对芒果细胞壁降解酶、类胡萝卜素含量的作用 总被引:6,自引:0,他引:6
芒果后熟初期上部和内部PG活性高于下部和外部。后熟期PG活性上升至高峰后下降,PME活性则不断下降。ABA能使PG活性增高,GA3则抑制了PG活性,并推迟了PG活性的高峰期。不过,GA3或ABA处理对后熟期PME活性都没有一致的影响。芒果后熟期α-胡萝卜素、α-胡萝卜素和叶黄素含量不断升高,GA3能使三者上升速度减缓;ABA则显著加快β-胡萝卜素和叶黄素的上升。从外源β-胡萝卜素引起PG活性上升的结果,讨论了后熟期类胡萝卜素与PG活性的间接关系。 相似文献
87.
Alfalfa plants were regenerated from callus cultures of three source plants that differed in resistance to anthracnose, caused by Colletotrichum trifolii. All regenerant plants were evaluated for variation in resistance to disease caused by races 1 and 2 of the pathogen. Of eighty-two plants that were regenerated and evaluated, no plants responded differently to inoculation with race 1 of C. trifolii, but two plants (2.4%) differed in resistance when inoculated with race 2. The source plant of these regenerants was resistant to races 1 and 2 of the pathogen but the regenerants were resistant to race 1 and susceptible to race 2. No variants to race 1 were detected. The susceptible response of the variant plants to race 2 was confirmed by cytological analysis and was consistent with the response of nonregenerant susceptible plants. These plants represent a near-isogenic plant model for studying the molecular biology of resistance and susceptibility to anthracnose of alfalfa. 相似文献
88.
Induction of Somatic Embryogenesis and Plant Regeneration of ‘Ataulfo’ Mango (Mangifera indica) 总被引:1,自引:0,他引:1
Rivera-Domínguez Marisela Manzanilla-Ramírez Miguel Angel Robles-González Manuel Gómez-Lim Miguel Angel 《Plant Cell, Tissue and Organ Culture》2004,79(1):101-104
Nucellar explants from the immature fruit of Ataulfo mango, 3–4 cm long, were used. The process had a very low efficiency (<10%); however, Ataulfo was more embryogenic than other cultivars such as Tommy Atkins or Haden in our hands. Overall, the process from nucellus to plantlet stage took 5 months. Twelve regenerated plants were obtained and are currently growing in the greenhouse. They appear to be normal and free of abnormalities. Some biochemical and molecular tests are currently being carried out. 相似文献
89.
The aim of this study was to investigate under a controlled environment, the effect of temperature on the survival and infectivity
of Pseudotheraptus devastans Distant, a cassava anthracnose disease vector. The insect P. devastans was collected from young cassava (Manihot esculenta Crantz) field plots, at the International Institute of Tropical Agriculture, (IITA), Ibadan, Nigeria. A mixture of the different
developmental stages of eggs, first to fifth instar nymphs, and adults, were incubated in controlled environment chambers,
under various constant temperatures of: 15, 17, 22, 25, 27, 30, and 35°C. Relative humidity at different temperature conditions
were recorded and maintained at 90%, 85%, 80%, 75%, 70%, 65%, and 60%, respectively. A significant increase in insect survival
was observed between 22 and 27°C temperature conditions while a significant decrease in survival was observed at 15°C and
above 30°C. Lesion number, lesion diameter and infectivity among the insect stages varied as a function of temperature and
relative humidity. Infectivity was highest at 22–25°C maintained at 75–80% RH and lowest at 15°C and above 30°C maintained
respectively, at 65% RH and 90% RH. There was considerable low vector infectivity due to low survival of the insects at extreme
temperatures. 相似文献
90.