Saftner R A, Evans M L
Department of Botany, The Ohio State University, Columbus, Ohio 43210.
Plant Physiol. 1974 Mar;53(3):382-7. doi: 10.1104/pp.53.3.382.
Victorin, the pathotoxin from the host-specific pathogen, Helminthosporium victoriae, promotes the growth of coleoptile segments when given at concentrations that are high but which still show selective effects on susceptible and resistant tissue. The latent period in the growth response of both susceptible and resistant tissue is about 3.6 minutes compared to 11.0 minutes in the response of these tissues to auxin. The victorinpromoted rate of elongation of 8-millimeter segments is about 0.2 millimeter per hour in susceptible tissue and about 0.1 millimeter per hour in resistant tissue compared to about 0.4 millimeter per hour in response to auxin. At low concentrations, the toxin has no growth-promoting effect in either susceptible or resistant coleoptile segments. Over a wide range of concentrations, victorin inhibits the growth response of susceptible tissue to auxin completely while having no effect on the response of resistant tissue to auxin.Victorin induces solute leakage in coleoptile tissue of susceptible but not resistant varieties of Avena. In susceptible tissue, solute leakage begins about 2 minutes after the addition of toxin and continues for at least 4 hours.The rapidity and close correlation of toxin effects on membrane permeability (2 minutes) and on growth (3.6 minutes) suggest the possibility that the initial action of victorin in both cases may be at the cell surface, perhaps the plasmalemma.
维多利亚毒素是由宿主特异性病原菌维多利亚长蠕孢菌产生的致病毒素，当以高浓度给予时，它能促进胚芽鞘切段的生长，但这些高浓度仍对敏感组织和抗性组织表现出选择性作用。敏感组织和抗性组织生长反应的潜伏期约为3.6分钟，而这些组织对生长素反应的潜伏期为11.0分钟。在敏感组织中，维多利亚毒素促进8毫米切段伸长的速率约为每小时0.2毫米，在抗性组织中约为每小时0.1毫米，而对生长素反应的伸长速率约为每小时0.4毫米。在低浓度下，该毒素对敏感或抗性胚芽鞘切段均无促进生长的作用。在很宽的浓度范围内，维多利亚毒素完全抑制敏感组织对生长素的生长反应，而对抗性组织对生长素的反应没有影响。维多利亚毒素能诱导燕麦敏感品种而非抗性品种的胚芽鞘组织溶质渗漏。在敏感组织中，加入毒素后约2分钟开始溶质渗漏，并持续至少4小时。毒素对膜通透性（2分钟）和生长（3.6分钟）影响的快速性和紧密相关性表明，在这两种情况下，维多利亚毒素的初始作用可能都发生在细胞表面，也许是质膜。
