【摘要】 小麦发芽四天的第一片幼叶切段在含有2,4-D 并略加修改的 PRL-4培养基上,可以形成愈伤组织,并由愈伤组织生根、出苗形成再生植株。愈伤组织出现频率及生长速度与叶段部位及2,4-D 浓度有关。在2,4-D 浓度4ppm 以内,能诱导产生愈伤组织的部位是从基部至其上1 cm 左右的区域。激动素(KT)和6-苄基腺嘌呤(BA)均明显抑制愈伤组织的形成。解剖学观察表明愈伤组织来源于维管束鞘部位细胞的分裂。最后讨论了小麦叶肉原生质体培养未能成功的原因。更多还原

【Abstract】 Callus was obtained on modified PRL-4 medium supplemented with 2,4-D from the segments of the first leaf of wheat seedling which had been germinated for 4 days.Roots and shoots were initiated and complated plantlets thus regenerated.The frequency of callus formation and its growth rate depended upon the concentration of 2,4-D and the locations of segments on the leaf.When the concentration was 4 ppm or less,the callus could be produced only within the region from the leaf base to about 1 cm apart.Both KT and 6-BA were inhibitory to callus formation.Histo- logical examination showed that callus originated from the cells located at the place of vascular bundle sheath.The roots were frequently induced from leaf callus.During the process of callus induction,after 10—14 days incubation,the roots began to ap- pear in the medium containing 2,4-D of 2 ppm or less.The lower the concentra- tion,the nearer to the base of the leaf the root-forming place was.In contrast,the higher concentration induced rooting at the higher part of the leaf but inhibited at the lower place.After 3 weeks incubation,the highest frequency of root differ- entiation was about 60%.The callus failed to differntiate in short-period incubation in higher concentration of 2,4-D,but when it was transferred to lower level,roots could be initiated.Shoot and plantlets were regenerated from callus cultured in several phytohormone combinations and under different conditions.But the frequency of shooting was very low,and some seedling were morphologically abnormal.The nature of shooting is not yet clear and further studies should be carried on.In this paper,causes of failure in the protoplas~+ culture of mesophyll tissue of wheat leaf were also discussed.更多还原