湿地松组培再生植株瓶内菌根化及驯化移栽

为提高湿地松Pinus elliottii微繁殖效率，对湿地松丛生芽发生条件进行了优化，并对再生植株离体条件下菌根的形成进行了探索。结果表明，基本培养基、外植体年龄对湿地松带子叶顶芽丛生芽诱导有较大影响。改良GD（Gresshoff and Doy）为最佳基本培养基，苗龄以18 ~ 25 d为宜。改良GD培养基中加入0.5 mg·L^－1活性炭能促进丛生芽的伸长生长。将改良GD培养基中大量元素减半并添加0.05 mg·L^－1α-萘乙酸（NAA）和1.0 mg·L^－1吲哚丁酸（IBA）使嫩梢生根率达80 %，生根的小植株与外生菌根真菌彩色豆马勃Pisolithus tinctorius在离体条件下形成菌根。菌根的形成提高了再生植株的驯化移栽成活率。再生植株在田间生长正常，3 a后平均高度为80.3 cm。图2表4参28

Mycorrhiza formation and acclimatization of tissue cultured Pinus elliottii

The condition for axillary bud induction of Pinus elliottii has been optimized,and mycorrhizas on the rooted explants has been tested in vitro to improve the efficiency of micropropagation. Axillary bud induction was found to be influenced by the basal medium as well as the age of the seedling from which the explant was taken. Modified Gresshoff and Doy＇s （GD） medium proved to be superior to others,and the right stage of seedling was 18-25 d. The addition of activated charcoal（0.5 mg·L-1） stimulated shoot elongation. Rooting occured at about 80% on 1/2GD medium supplemented with 0.05 mg·L-1 NAA and 1.0 mg. L-1 IBA. Mycorrhizas were initiated for plantlets with Pisolithus tinctorius on an agar medium under fully controlled conditions. Mycorrhizas improved the transfer of the plantlets to ex vitro conditions. After 3 years in the field,the plantlets reached an average of 80.3 cm in height. Their shoot growth appearance was normal.