以黑莓(Rubus spp.)品种‘Chester’带腋芽茎段为外植体,对初代培养基、不定芽增殖培养基和生根培养基中适宜的激素种类及浓度进行了筛选,并对增殖培养过程中适宜的光照度进行了研究。结果显示,在初代培养基中添加不同质量浓度的6-BA 和NAA 对侧芽的萌发和生长有明显的影响,其中,NAA 不利于芽的萌发和生长,而添加适量的6-BA 可促进芽的萌发和生长;适宜于‘Chester’茎段的初代培养基为添加了1. 00 mg·L^-16-BA 的MS 培养基(含25 g·L^-1 蔗糖和5. 9 g·L^-1 琼脂,pH 5. 8)。单因素实验结果显示,在‘Chester’不定芽的增殖过程中,细胞分裂素主要影响不定芽增殖,而生长素主要影响不定芽生长,以质量浓度低于1. 0 mg·L^-1 的6-BA 以及质量浓度低于0. 3 mg·L^-1 的NAA 较为适宜;经过进一步的组合筛选,确定适宜于‘Chester’不定芽增殖的培养基为添加了0. 5 mg·L^-16-BA 和0. 1 mg·L^-1 NAA 的MS 培养基(含25 g·L^-1 蔗糖和5. 9 g·L^-1 琼脂,pH 5. 8)。在生根培养基中添加高浓度NAA 易诱导不定芽基部产生愈伤组织,不利于不定芽生根,因而,‘Chester’不定芽适宜的生根培养基为添加了0. 10 mg·L^-1 NAA 的1/2MS 培养基(含20 g·L^-1 蔗糖和5. 9 g·L^-1 琼脂,pH 5. 8)。在不定芽的增殖培养过程中,光照度较强有利于不定芽生长,适宜的增殖培养条件为:光照度3 000 lx、光照时间15 h·d^-1 、温度(25±2) ℃、相对湿度约70%,此条件下不定芽的增殖系数(1. 95)和平均芽长(1. 44 cm)最高,芽生长状况良好。

Suitable type and concentration of phytohormone in initial culture medium, proliferation and rooting culture media of adventitious bud were selected using the stem segment with an axillary bud of blackberry (Rubus spp.) cultivar ‘Chester’as explants, and also suitable illumination intensity during proliferation culture process was studied. The results show that in initial culture medium, different concentrations of 6-BA and NAA have significant influence on germination and growth of lateral bud, in which, NAA is unfavorable but 6-BA with an appropriate amount could promote germination and growth of bud. The initial culture medium suitable for ‘Chester’stem segment is MS (containing 25 g·L^-1 sucrose and 5. 9 g·L^-1 agar, pH 5. 8) with 1. 00 mg·L^-1 6-BA. The single factor experiment result reveals that cytokinin mainly affects on proliferation while auxin mainly affects on growth during proliferation process of adventitious bud, and the medium with 6-BA concentration below 1. 0 mg·L^-1 and NAA concentration below 0. 3 mg·L^-1 is more appropriate. Through a further combinative selection, it is determined that the medium suitable for proliferation of ‘ Chester’adventitious bud is MS (containing 25 g·L^-1 sucrose and 5. 9 g·L^-1 agar, pH 5. 8) with 0. 5 mg·L-1 6-BA and 0. 1 mg·L^-1 NAA. The rooting medium with high concentrations of NAA may easily induce to form. callus at adventitious bud base and be unfavorable for rooting, thus, the optimum medium for rooting of ‘Chester’

adventitious bud is 1/2MS (containing 20 g·L^-1 sucrose and 5. 9 g·L^-1 agar, pH 5. 8) with 0. 10 mg·L^-1 NAA. The higher illumination intensity is beneficial to bud growth during proliferation process of adventitious bud, and suitable condition for proliferation culture is illumination intensity 3 000 lx, illumination time 15 h·d^-1, temperature (25±2) ℃and relative humidity about 70%. Under such condition, the growth state of adventitious bud is better with the highest proliferation coefficient (1. 95) and average bud length (1. 44 cm).