Institute for Horticultural Plant Breeding (IVT), P.O.B. 16, NL-6700, AA Wageningen, The Netherlands.
Theor Appl Genet. 1988 Aug;76(2):204-8. doi: 10.1007/BF00257847.
Effects of the phytotoxic compounds (AAL-toxins) isolated from cell-free culture filtrates of Alternaria alternata f.sp. lycopersici on in vitro pollen development were studied. AAL-toxins inhibited both germination and tube growth of pollen from several Lycopersicon genotypes. Pollen from susceptible genotypes, however, was more sensitive for AAL-toxins than pollen from resistant plants, while pollen of species not belonging to the host range of the fungus was not significantly affected by the tested toxin concentrations. AAL-toxins elicit symptoms in detached leaf bioassays indistinguishable from those observed on leaves of fungal infected tomato plants, and toxins play a major role in the pathogenesis. Apparently, pathogenesis-related processes and mechanisms involved in disease resistance are expressed in both vegetative and generative tissues. This overlap in gene expression between the sporophytic and gametophytic level of a plant may be advantageously utilized in plant breeding programmes. Pollen may be used to distinguish susceptible and resistant plants and to select for resistances and tolerances against phytotoxins and other selective agents.
从番茄早疫病菌（Alternaria alternata f.sp. lycopersici）无细胞培养滤液中分离得到的植物毒性化合物（AAL 毒素）对花粉体外发育的影响进行了研究。AAL 毒素抑制了来自几种番茄基因型的花粉萌发和管生长。然而，易感基因型的花粉对 AAL 毒素比抗性植物的花粉更为敏感，而不属于真菌寄主范围的物种的花粉则不受测试毒素浓度的显著影响。AAL 毒素在离体叶片生物测定中引发的症状与在真菌感染的番茄叶片上观察到的症状无法区分，毒素在发病机制中起主要作用。显然，与抗病性相关的过程和机制在营养组织和生殖组织中都有表达。植物的孢子体和配子体水平之间基因表达的这种重叠可以在植物育种计划中得到有利的利用。花粉可用于区分易感和抗性植物，并选择对植物毒素和其他选择剂的抗性和耐受性。
