Avni A, Edelman M
Department of Plant Genetics, Weizmann Institute of Science, Rehovot, Israel.
Mol Gen Genet. 1991 Feb;225(2):273-7. doi: 10.1007/BF00269859.
The response of Nicotiana tabacum to tentoxin (chlorosis) is inherited with chloroplasts. N. tabacum var. Xanthi, a tentoxin-resistant line, was used to pollinate tentoxin-sensitive N. tabacum line 92, an alloplasmic male-sterile line containing N. undulata plastids. The seeds were mutagenized with nitrosomethylurea and germinated in the presence of tentoxin. Two percent of the seedlings had green sectors in their first true leaves. These plants were grown to maturity under non-selective conditions. Homogeneous tentoxin-resistant lines were obtained in the third generation. DNA analysis indicated, however, that selection for paternal plastids, rather than mutagenesis of maternal ones, had occurred in the tentoxin-resistant progeny. Mitochondria, which were not under selection pressure, were inherited maternally as expected. Inheritance of tentoxin-resistant paternal plastids did not require seed mutagenesis. Normally germinated seedlings that were kept under tentoxin selection consistently produced a low level of resistant green sectors in their first true leaves. Thus, normal, low-frequency transmission of paternal plastids in N. tabacum can be directly revealed by using tentoxin.
烟草对毒素（黄化）的反应是由叶绿体遗传的。烟草品种Xanthi是一种抗毒素品系，用于给对毒素敏感的烟草品系92授粉，品系92是一种含有波浪烟草质体的异质细胞质雄性不育系。种子用亚硝基甲基脲诱变，并在毒素存在的情况下萌发。2%的幼苗在其第一片真叶上有绿色区域。这些植株在非选择性条件下生长至成熟。在第三代获得了同质抗毒素品系。然而，DNA分析表明，在抗毒素后代中发生的是父本质体的选择，而不是母本质体的诱变。未处于选择压力下的线粒体如预期那样由母本遗传。抗毒素父本质体的遗传不需要种子诱变。在毒素选择下正常萌发的幼苗在其第一片真叶上始终会产生低水平的抗性绿色区域。因此，通过使用毒素可以直接揭示烟草中父本质体正常的低频传递。
