Tabei Y, Kitade S, Nishizawa Y, Kikuchi N, Kayano T, Hibi T, Akutsu K
National Institute of Agrobiological Resources (NIAR), Tsukuba, Ibaraki 305, Japan Fax-no.: +81-298-38-7073 E-mail:
Faculty of Agriculture, Ibaraki University, Ami-machi, Ibaraki 300-03, Japan, , , , , , JP.
Plant Cell Rep. 1998 Jan;17(3):159-164. doi: 10.1007/s002990050371.
A rice chitinase cDNA (RCC2) driven by the CaMV 35S promoter was introduced into cucumber (Cucumis sativus L.) through Agrobacterium mediation. More than 200 putative transgenic shoots were regenerated and grown on MS medium supplemented with 100 mg/l kanamycin. Sixty elongated shoots were examined for the presence of the integrated RCC2 gene and subsequently confirmed to have it. Of these, 20 were tested for resistance against gray mold (Botrytis cinerea) by infection with the conidia: 15 strains out of the 20 independent shoots exhibited a higher resistance than the control (non-transgenic plants). Three transgenic cucumber strains (designated CR29, CR32 and CR33) showed the highest resistance against B. cinerea: the spread of disease was inhibited completely in these strains. Chitinase gene expression in highly resistant transgenic strains (CR32 and CR33) was compared to that of a susceptible transgenic strain (CR20) and a control. Different responses for disease resistance were observed among the highly resistant strains. CR33 inhibited appressoria formation and penetration of hyphae. Although CR32 permitted penetration of hyphae, invasion of the infection hyphae was restricted. Furthermore, progenies of CR32 showed a segregation ratio of 3:1 (resistant:susceptible). As the disease resistance against gray mold was confirmed to be inheritable, these highly resistant transgenic cucumber strains would serve as good breeding materials for disease resistance.
一个由花椰菜花叶病毒35S启动子驱动的水稻几丁质酶cDNA（RCC2）通过农杆菌介导被导入黄瓜（Cucumis sativus L.）中。200多个推定的转基因芽在添加了100 mg/l卡那霉素的MS培养基上再生并生长。对60个伸长的芽进行了检测，以确定是否存在整合的RCC2基因，随后证实它们含有该基因。其中，20个通过接种分生孢子来检测对灰霉病（Botrytis cinerea）的抗性：20个独立芽中的15个菌株表现出比对照（非转基因植物）更高的抗性。三个转基因黄瓜菌株（命名为CR29、CR32和CR33）对灰霉病菌表现出最高的抗性：在这些菌株中疾病的传播被完全抑制。将高抗性转基因菌株（CR32和CR33）中的几丁质酶基因表达与一个敏感转基因菌株（CR20）和一个对照进行了比较。在高抗性菌株中观察到了对疾病抗性的不同反应。CR33抑制附着胞的形成和菌丝的穿透。虽然CR32允许菌丝穿透，但侵染菌丝的入侵受到限制。此外，CR32的后代表现出3:1（抗性:敏感）的分离比。由于已证实对灰霉病的抗性是可遗传的，这些高抗性转基因黄瓜菌株将成为良好的抗病育种材料。
