SURVIVAL OF PSEUDOMONAS-SOLANACEARUM IN SOIL, RHIZOSPHERE, AND PLANT-ROOTS
SURVIVAL OF PSEUDOMONAS-SOLANACEARUM IN SOIL, RHIZOSPHERE, AND PLANT-ROOTS
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DOI：
10.1139/m83-070
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发表时间：
1983-01-01
影响因子：
2.8
通讯作者：
SEQUEIRA, L
中科院分区：
文献类型：
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作者：
GRANADA, GA;SEQUEIRA, L
使用一种新的选择性培养基来确定不同青枯菌菌株在土壤中或与温室中植物根部相关的生存能力。当种族 1 的 2 种菌株、种族 2 的两种菌株和种族 3 的一种菌株在土壤-沙子混合物（.psi. = -2 巴 = 100 kPa [千帕]）中存活时，28°C。 C，经测定，每个菌株的种群以不同的速度下降，但没有一个菌株存活超过 24 周。为了研究青枯菌在根际的存活率，将抗性寄主（辣椒、番茄、蓖麻子）和假定非寄主（豆类、玉米）的幼苗通过将其根浸入细菌悬浮液中进行接种，然后重新种植。在长达 33 周的不同时间间隔内测定根际细菌种群。病原体无法在根际生存；当检测到大量种群时，它们与未表现出枯萎症状的植物根部的局部或全身感染有关。当在不同时间收集接种植物的根部，然后将其浸入 70% 乙醇中 5 分钟进行表面消毒时，每次处理中的许多植物中都恢复了高数量的细菌。实验表明，这种感染不是人工接种程序的结果，在这些实验中，假定的非寄主植物，如菜豆、豌豆、大豆、玉米、高粱和水稻，是用种植在被1号种族菌株感染的土壤中的种子培育出来的。在这些植物的整个生长周期中，从表面灭菌的根部恢复了大量的细菌。因此，青枯菌的长期存活显然与其感染植物根部的能力相关。
A new, selective medium was used to determine the ability of different strains of P. solanacearum to survive in the soil or in association with plant roots in the greenhouse. When survival of 2 strains of race 1, two of race 2, and one of race 3 in soil-sand mixture (.psi. = -2 bars = 100 kPa [kilopascal]), 28.degree. C, was determined, populations of each strain declined at different rates, but none of the strains survived beyond 24 wk. To study survival of P. solanacearum in the rhizosphere, seedlings of resistant hosts (pepper, tomato, castor bean) and presumed nonhosts (bean, corn) were inoculated by dipping their roots in a bacterial suspension and then replanted. Bacterial populations in the rhizosphere were determined at various intervals up to 33 wk. The pathogen was not able to survive in the rhizosphere; when high populations were detected, they were associated with localized or systemic infection of the roots of plants that did not show wilt symptoms. When the roots of inoculated plants were collected at different times and then surface sterilized by immersing them in 70% ethanol for 5 min, high populations of the bacterium were recovered from many of the plants in each treatment. That infection was not the result of the artificial inoculation procedures used was shown in experiments in which presumed nonhost plants, such as bean, peas, soybean, corn, sorghum and rice, were grown from seed planted in soil infested with strains of race 1. High populations of the bacterium were recovered from surface-sterilized roots throughout the growth cycle of these plants. Thus, long-term survival of P. solanacearum apparently was correlated with its ability to infect plant roots.