不同激素组合对番茄离体再生和相关基因表达的影响

以樱桃番茄材料J6的子叶和下胚轴为试验对象,分别在激素组合A(2 mg·L^-1 6-BA+0/0.1/0.2/0.3 mg·L^-1 IAA,依次编号为A1、A2、A3、A4)、组合B(2 mg·L^-1 ZT+0/0.1/0.2/0.3 mg·L^-1 IAA,依次编号为B1、B2、B3、B4)的MS培养基上进行培养,研究不同激素组合对不同时期的番茄子叶和下胚轴脱分化、再分化情况,以及脱分化基因和再分化基因表达的影响。结果表明:外植体培养至第10天,子叶的脱分化率在所有处理下为100%,但脱分化基因的表达量相差较大;与B组合相比,A组合的下胚轴脱分化率更高,所有脱分化基因表达量也显著(P<0.05)上调。培养至第20 d,子叶愈伤组织在B组合下形态良好,脱分化基因Solyc01g091420.2.1、Solyc04g072900.1.1和Solyc04g054910.3.1表达量在B1和B2处理下显著上调;下胚轴愈伤形态在所有处理下疏松透亮,所有脱分化基因表达量只在B2处理下显著上调。培养至第60 d,子叶再分化率在B1和B2处理下最高,为67%和58%,再分化基因Solyc05g013540.1.1、Solyc02g022850.1.1和Solyc10g052510.2.1在B1和B2处理下高表达;下胚轴再分化率和基因表达量在所有处理下均较低。综上所述,番茄材料J6以子叶为外植体,在2 mg·L^-1 ZT+0/0.1 mg·L^-1 IAA的激素组合下离体再生效果最好,脱分化基因Solyc01g091420.2.1、Solyc04g072900.1.1、Solyc04g054910.3.1和再分化基因Solyc05g013540.1.1、Solyc02g022850.1.1、Solyc10g052510.2.1与子叶离体再生过程密切相关,从分子层面证实了不同激素组合处理对调控番茄不同类型外植体脱分化、再分化过程有重要影响。

Effects of different hormone combinations on tomato in vitro regeneration and related gene expression

Cotyledons and hypocotyls of cherry tomato material J6 were cultured on MS medium supplemented with hormone combinations A(2 mg·L^-1 6-BA+0/0.1/0.2/0.3 mg·L^-1 IAA, numbered A1, A2, A3, A4) and B (2 mg·L^-1 ZT+0/0.1/0.2/0.3 mg·L^-1 IAA, numbered B1, B2, B3, B4), respectively, so as to study the effects of different hormone combinations on the dedifferentiation and redifferentiation of cotyledons and hypocotyls at different stages, as well as the expression of dedifferentiation genes and redifferentiation genes. The results showed that the dedifferentiation rate of cotyledons was 100% in all treatments at the 10th day, but expression level of dedifferentiation genes differed greatly. Compared with combination B, the dedifferentiation rate of hypocotyls under combination A was higher and expression level of all dedifferentiation genes were also significantly (P<0.05) up-regulated. On the 20th day, callus morphology of cotyledon was better under combination B, and expression level of dedifferentiation genes Solyc01g091420.2.1, Solyc04g072900.1.1 and Solyc04g054910.3.1 were significantly up-regulated under treatment B1 and B2. The callus morphology of hypocotyl was loosed and bright under all treatments, and the expression level of all dedifferentiated genes were significantly up-regulated only under treatment B2.On the 60th day, the redifferentiation rate of cotyledons under treatment B1 and B2 reached 67% and 58%, and the redifferentiation genes Solyc05g013540.1.1, Solyc02g022850.1.1 and Solyc10g052510.2.1 were highly expressed. The redifferentiation rate and gene expression level in hypocotyls were lower in all treatments. In conclusion, cotyledons of J6 had the best regeneration effect in vitro under the treatment of 2 mg·L^-1 ZT+0/0.1 mg·L^-1 IAA. The dedifferentiation genes Solyc01g091420.2.1, Solyc04g072900.1.1 and Solyc04g054910.3.1, and the redifferentiation genes Solyc05g013540.1.1, Solyc02g022850.1.1 and Solyc10g052510.2.1 were closely related to the regeneration process. It was also confirmed that different hormone combinations had important effects on regulating the dedifferentiation and redifferentiation process of different types of tomato explants.