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近年来人们对食品安全性担忧情绪持续发酵,国家对食品安全高度重视,积极推动农产品进行无公害、绿色、有机生产,以提高食品的安全性.苹果作为重要农产品进行有机生产是必然的,本文回顾了我国苹果有机生产的过程,指出我国有机苹果发展缓慢的原因,分析有机苹果发展前景,提出有机苹果生产中需注意的关键性问题. 相似文献
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西瓜甜瓜危险性病害——细菌性果腐病 总被引:2,自引:0,他引:2
细菌性果腐病(BacterialFruitBlotch,简称BFB)由Acidovoraxavenaesubsp.citrulliWillemsetal引起,是西瓜、甜瓜的1种危险性新细菌病害,是国际规定的检疫性有害生物之一。1概况1965年Webb等人犤1犦首先发现于美国佛罗里达州的西瓜上。1978年,Schaad等人首次鉴定了美国佐治亚州的西瓜苗凋萎病病原为类产碱假单胞西瓜亚种(Pseudomonaspseudoalcaligenessubsp.citrulliSchaadetal.1978)。1989年,此病在美国的商品瓜生产田发生越来越重,扩展至美国的9个州,病害开始病害名称病原菌细菌性角斑病犤3~5犦(Bacterialangular)细菌性凋萎病犤3,4… 相似文献
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从苹果斑点落叶病菌(Alternaria mali Roberts)的Richards培养液中提取的AM—毒素,在254nm处有吸收峰。经叶片法、插枝法、电导率法等生物测试表明,AM—毒素具有寄主专化性。以AM—毒素为选择因子,配制成选择培养基,以感病品种岩富10、新乔纳金、国光、新红星的愈伤组织为材料,采用多步选择系统筛选抗病突变体。所得到的抗病系离开选择因子2个月后,仍保持获得的抗病性。与未经选择的原始型相比,抗病系的苯丙氨酸解氨酶活性增强,过氧化物酶同工酶带减少1~3条。在AM—毒素作用下,抗病系电导率增加速度显著小于原始型。接种病原菌孢子后,抗病系较原始型抗病。 相似文献
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以苹果叶片总RNA为模板,通过克隆获得抗苹果斑点落叶病基因Mal d 1。Mal d 1开放阅读框长度为480 bp,编码159个氨基酸残基,包含2个外显子和1个内含子。蛋白结构分析显示,Mal d 1蛋白包含bet v 1-like结构域。荧光定量PCR分析结果表明,Mal d 1在苹果叶、花、果皮、果肉中均有表达,但各器官中表达水平存在差异;在不同发育时期的果皮中都有表达,表达水平随时间呈现先上升后下降的趋势;在抗性品种叶片中表达水平较高;在叶片人工接种病菌条件下表达量随时间的延长明显高于对照组。利用PRI101-AN载体和农杆菌介导的遗传转化方法转化苹果愈伤组织,转基因愈伤组织的抗病鉴定结果显示,Mal d 1过量表达增强愈伤组织对苹果斑点落叶病的抗性。 相似文献
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J. K. Eaton 《The Journal of Horticultural Science and Biotechnology》2013,88(2):128-131
SummaryActively growing, single-stemmed plants of three black currant cultivars, each with 15 – 16 nodes, were exposed to photoperiods of 10, 14, 15, 16, 17, 18, 20, and 24 h at 18°C for 8 weeks for determination of the critical photoperiods for growth cessation and floral initiation. In all three cultivars, growth cessation was induced by short day (SD) conditions, with a critical photoperiod of 16 h, and the response was advanced by decreasing the photoperiod. The critical photoperiod for 50% flowering was 16 h in the cultivars ‘Öjebyn’ and ‘Ben Tron’, and 17 h in ‘Kristin’. Unexpectedly, however, not all plants flowered after exposure to a 10 h photoperiod, and the number of flowers per plant increased several-fold as the photoperiod was increased from 10 h to 15 h in all cultivars. Apparently, this unexpected result was due to the fact that all plants had only 15 – 16 nodes at the start of the experiments, which is marginal for “ripeness to flower” in black currant. While growth cessation was almost immediate in a 10 h photoperiod, causing only a few additional leaves to be formed during the experiment, the slower response to longer photoperiods apparently enabled the plants to reach the critical size at an earlier stage of the treatment period. However, although plants with 15 – 16 nodes were only marginally responsive to SD induction, buds situated as far down the shoot as the fifth or sixth node were competent to flower. It is therefore suggested that the inability of small black currant plants to flower resides in limitations of the leaves to respond to SD and to produce a florigenic signal, while their buds are fully competent to respond to such a signal. 相似文献
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细菌性果腐病(BacterialFruitBlotch,BFB)在1989年美国首次报道以来,已给西、甜瓜生产造成了相当大的危害犤1犦。但在我国该病的危害和对西、甜瓜生产的潜在威胁仍未引起足够重视,甚至在某些地区还未得到正确的诊断,如不及时采取充分有效的措施,西瓜细菌性果腐病将有可能给某些地区的西、甜瓜生产造成毁灭性损失。这决非危言耸听,在美国等国已发生过,故美国将其视为西瓜的“瘟疫”或“癌症”,许多西瓜生产农场、育苗场与种子公司付出了惨重的代价。本文简述了细菌性果腐病在世界发生的过程与危害程度,描述了细菌性果腐病的病原菌、症状、… 相似文献
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苹果基因组分子生物学研究进展 总被引:4,自引:1,他引:4
借助分子标记手段苹果基因组研究取得了巨大成就,涉及苹果的抗性、生长发育、果实品质等各方面基因,综合有关文献,将其研究的主要成果,包括已发现的主要苹果遗传标记、已构建的苹果遗传连锁图谱及苹果的转基因研究进行综述,并对目前苹果基因组研究存在的问题和对策进行了分析,以期为苹果遗传育种提供参考。 相似文献
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W. G. Keyworth 《The Journal of Horticultural Science and Biotechnology》2013,88(3):163-168
Previous papers have described the effects of molybdenum on the growth (3) and composition (4, 5) of cauliflower plants grown with two levels of nitrate nitrogen. It was found that molybdenum deficiency resulted in decreased contents of chlorophyll, ascorbic acid, sugars and organic nitrogen. This paper describes results obtained with cauliflower plants grown with nitrogen as nitrate, nitrite, ammonium compounds, urea or glutamic acid. The intention was to compare the effects of molybdenum on growth and composition under different conditions of nitrogen nutrition. The results were obtained in two main experiments carried out in 1951 and 1952, of which the first was briefly noted (1), and in other experiments in 1953–54 in which additional confirmation of certain points was obtained. 相似文献
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黄斑病是严重影响糙皮侧耳(Pleurotus ostreatus)产量和品质的一种细菌性病害。本研究从山西省糙皮侧耳生产区采集的黄斑病样品中分离到病原菌菌株HB-1,对其进行了形态观察、分子鉴定与生理生化指标测定并研究了醋酸杆菌菌株BA15发酵液对该病原菌的防治作用。结果表明:该病原菌与公认的糙皮侧耳病原菌托拉斯假单胞杆菌(Pseudomonas tolaasii)不同,为解淀粉芽孢杆菌(Bacillus amyloliquefaciens);醋酸杆菌BA15发酵液对HB-1具有显著的抑制作用。本研究结果为糙皮侧耳黄斑病病原菌的鉴定及生物防治提供了参考。 相似文献
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以硫酸链霉素为对照药剂,通过平皿抑菌试验和活体药效试验,对3%中生菌素用于防治糙皮侧耳(Pleurotus ostreatus)细菌性褐斑病的效果进行评价。结果表明,3%中生菌素(37.57、5.0 mg/L)与硫酸链霉素(250 mg/L)对托拉斯假单胞杆菌(Pseudomonas tolaasii,细菌性褐斑病病原菌)的平皿抑制率均为100%;活体药效试验中,3%中生菌素(37.5 mg/L)与硫酸链霉素(250 mg/L)对糙皮侧耳细菌性褐斑病的预防效果均在80%以上,显著优于接种后施药处理的治疗效果。 相似文献
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