芸苔素内酯对石榴快繁体系及愈伤组织生长的影响

The effect of brassinolide on the rapid propagation system and callus growth of pomegranate

为建立‘突尼斯’软籽石榴(Punica granatum‘Tunisia’)的快繁体系,探究芸苔素内酯(Brassinolide,BR)对石榴愈伤组织诱导的效果,该研究分别以软籽石榴茎段和嫩芽作外植体,设置4个芸苔素内酯浓度水平(0、0.2、0.4、0.6mg·L^(-1)),通过测定茎秆高度、愈伤组织直径变化、叶绿素含量、过氧化物酶活性和丙二醛含量等指标,探究芸苔素内酯对石榴快繁苗生长发育的影响。结果显示:以茎段为外植体的组培苗污染率高,但发芽率和存活率同样较高,且长势良好,是更合适的外植体材料;0.4mg·L^(-1)的芸苔素内酯较其他浓度对‘突尼斯’软籽石榴快繁苗生长发育的效果更佳,加快了组培苗茎秆和愈伤组织生长速度,使叶片叶绿素含量、过氧化物酶活性较对照组分别提高了17.4%、20.0%,丙二醛含量较对照组降低了47.5%,可提高快繁苗的抗逆性。因此,一定浓度的外源芸苔素内酯可促进石榴愈伤组织诱导,有助于石榴离体培养体系的建立,为培育高质量的无菌苗提供理论基础和科学依据。

To establish a fast propagation system of Punica granatum Tunisia'and investigate the effect of brassinolide(BR)on callus induction in pomegranate,soft seed pomegranate stem segments and ten-der buds were used as explants,and stem height,callus diameter changes,chlorophyll content,peroxi-dase activity,and malondialdehyde content were used as evaluation indicators.Four levels of brassinol-ide concentration(0,0.2,0.4,0.6 mg·L^(-1))were set to explore their effects on the growth and develop-ment of fast propagation seedlings.The results showed that although tissue cultured seedlings with stem segments as explants had a higher contamination rate,their germination and survival rates were also high,and they grew well,making them more suitable explant materials.The effect of o.4 mg·L^(-1) brassinolide on the growth and development of‘Tunisian'soft seed pomegranate rapid propagation seedlings is the optimum compared to other concentrations.It accelerates the growth rate of the stem and callus tissue of the seedlings,increases the chlorophyll content and peroxidase activity of the leaves by 17.4% and 20.0%,respectively,and reduces the malondialdehyde content by 47.5%compared to the control group,which may improve the stress resistance of the rapid propagation seedlings.A certain concentration of exogenous brassinolide can promote the induction of callus in pomegranate tissue culture seedlings,which helps to establish an in vitro culture system for pomegranate and provides a theoretical and scientific basis for cultivating high-quality sterile seedlings.