The effect of ethylene inhibitors （AgNO3, AVG）, an ethyleneliberating compound （CEPA） and aeration on the formation of protocorm-like bodies of hybrid Cymbidium （Orchidaceae）

Protocorm-like bodies （PLBs） or thin cell layers （TCLs） derived from PLBs of hybrid Cymbidium Twilight Moon ＇Day Light＇ can induce new or neo-PLBs on Teixeira Cymbidium （TC） medium, which contains 0.1 mg/L a- naphthaleneacetic acid, 0.1 mg/L kinetin, 2 g/L tryptone and 20 g/L sucrose, and is solidified with 8 g/L Bacto agar. This study aimed to assess the response ofneo-PLB formation to an ethylene-liberating compound （2-chloroethylphosphonic acid （CEPA））, to two ethylene inhibitors （silver nitrate （AgNO3） and aminoethoxyvinylglycine （AVG））, and to aeration （made possible by using Milliseal~ or autoclaved filter paper）. AgNO3 at 1 or 2 mg/L in TC medium significantly increased the fresh weight of PLBs while 1 mg/L of AgNO3 also showed a significant increase in the number ofneo-PLB from both half-PLBs and from tTCLs. In contrast, AVG and CEPA inhibited neo-PLB formation. Neo-PLB formation from half-PLB or TCL explants in the presence of aeration resulted in significantly lower neo-PLB weight. The use of AgNO3 and aeration are alternative means to mass produce neo-PLBs for micropropagation purposes.     

大花萱草

大花萱草(Hemerocallis hybridus)又名多倍体萱草、一日花,为百合科萱草属多年生宿根草本植物,具短根状茎及纺锤形块根。叶基生、线状披针形、排成两列生长。花葶高达1米,圆锥花序,着花6—16朵,花冠漏斗状,花色丰富,有大红、橙红、粉红、玫瑰红、堇紫、乳白、米黄、柠檬黄及复合色,花期6-7月。蒴果长卵形,果期8—9月,种子黑色、具光泽、寿命3—5年。