银杏成熟胚乳培养的细胞组织学观察

诱导银杏（GinkgobilobaL．）成熟胚乳产生愈伤组织时无需胚的存在。单独使用生长素或在细胞分裂素／生长素为0．5～0．9的范围内均能诱导部分胚乳切块产生愈伤组织。并且在White＋Kt2．7mg·l-1＋2,4－D1．0mg·l-1＋NAA2．0mg·l-1的培养基上,愈伤组织的诱导率最高,达到83．3％。胚乳细胞脱分化进行有丝分裂和无丝分裂,其中无丝分裂可以观察到劈裂和缢裂两种类型。愈伤组织起源于胚乳表皮及其下方2～3层细胞,且愈伤组织的形成需经历一个“假愈伤组织化”阶段。

In vitro Culture of the Mature Endosperm of Ginkgo biloba L.and Cytohistological Studies

Experiment showed the callus of Ginkgo biloba mature endosperm could be induced without the existence of embryo. The segments of endosperm could differentiate callus by using auxin alone, or using cytokinin/auxin in the ratio ranging from 0. 5～0. 9. The highest callus induced ratio (83. 3% ) was obtained by cultured on White medium +Kt 2. 7mg· 1-1+2, 4-D 1. 0mg. 1-1 +NAA 2. 0 mg·1-1. The result of cytohistological study showed both amitosis and mitosis occurred during cell dedifferentiation, and callus originated from endosperm epidermis and 2～3 sublayer cells. It was revealed that during the development of callus, there was a "falsecallused" stage.