蔗糖对发根农杆菌C58C1诱导烟草毛状根生长的影响

Effects of sucrose on growth of tobacco hairy roots induced by Agrobacterium rhizogenes C58C1

关键词:  毛状根, 蔗糖, 培养基优化, 分枝数, 鲜重, 干重

Key words:  hairy root, sucrose, optimization of medium, branch number, fresh weight, dry weight

摘要:

毛状根良好的生长状况是建立毛状根-AM真菌双重培养体系的关键,为优化毛状根培养基成分,确定适宜毛状根生长的蔗糖浓度,改善烟草毛状根的生长状况,该研究以发根农杆菌菌株C58C1诱导2个烟草品种NC82和Va116叶片产生毛状根,经PCR检测证实后,用含有不同蔗糖浓度的1/2MS培养基分别进行固体和液体优化培养,通过测定毛状根的分枝数、鲜重(FW)与干重(DW),研究蔗糖对2个品种烟草毛状根生长的影响。结果表明:(1)C58C1均能诱导两种烟草叶片产生毛状根,但诱导率不同,NC82(87.3%)的诱导率更高,是Va116(38.6%)的2.26倍。(2)培养基蔗糖浓度显著影响毛状根生长,因烟草品种和起始分枝数而异。(3)固体培养基优化培养NC82和Va116的毛状根,分枝数增长的抑制蔗糖浓度分别为25 g·L^-1和15 g·L^-1; 液体培养基优化培养分别在25 g·L^-1和15 g·L^-1时F(D)W达到最大,分别为0.541 g(0.055 g)、0.474 g(0.050 g)。(4)综合分枝数、F(D)W、毛状根生长势考虑,C58C1诱导NC82毛状根最适培养基蔗糖浓度为25 g·L^-1,Va116毛状根为15 g·L^-1。该文优化了烟草毛状根培养基组成的适宜蔗糖浓度及培养方法,为后续毛状根大量扩繁奠定基础,建立了毛状根-AM真菌双重培养体系,解决了关键的寄主生长不良的问题。

Abstract:

As the host, the hairy roots have good growth conditions, which is the key to establish the hairy root-AM fungus dual culture system. In order to optimize the medium composition, to screen the sucrose concentration suitable for the growth of hairy roots and to improve the growth of tobacco hairy roots, leaf growth of two types of tobacco, NC82 and Va116 were induced to have hairy roots through solid and liquid culture on 1/2MS medium with different sucrose concentrations and confirmed by PCR. The effects of sucrose on the growth of two tobacco hairy roots were studied by measuring the number of branches, fresh weight(FW)and dry weight(DW)of hairy roots. The results were as follows:(1)C58C1 could induce hairy roots in both tobacco leaves, but the induction rates were different. The induction rate of NC82(87.3%)was higher, which was 2.26 times that of Va116(38.6%).(2)The number of hairy root branches induced by NC82 and Va116 increased with the incubation time, and the increased amount varied with the concentration of sucrose. Sucrose has a significant effect on the growth of hairy roots, depending on the tobacco variety and the number of initial branches.(3)The solid medium was optimized to cultivate the induced NC82 and Va116 hairy roots, and the inhibitory sucrose concentrations for branch number growth were 25 g·L^-1 and 15 g·L^-1, respectively. In addition, the results of liquid optimized culture showed that the hairy roots induced by NC82 and Va116 reached the maximum F(D)W at 25 g·L^-1 and 15 g·L^-1, respectively, which were 0.541 g(0.055 g)and 0.474 g(0.050 g)respectively, which was mutually corroborated with solid optimized culture.(4)The present data suggested that the concentration of sucrose in the medium significantly affected the growth of hairy roots. Considering the number of branches, F(D)W, and hairy root growth vigor, C58C1 induced NC82 hairy roots with optimal sucrose concentration was 25 g·L^-1, and the hairy roots of Va116 was 15 g·L^-1. The study of tobacco hairy roots optimized the suitable sucrose concentration in the medium, laying a foundation for subsequent large-scale propagation of hairy roots; at the same time, established a hairy root-AM fungus double culturing system and solved the problem of poor growth of hairy roots as a host.