橡胶树1981'IRRDB野生种质苗期初生乳管分化的研究

摘要

巴西橡胶树的乳管是产生和贮存天然橡胶的组织.成龄树树干中的次生乳管因与割胶生产直接相关得到了全面的研究,而幼茎、 叶初生生长形成的初生乳管因与天然橡胶生产没有直接关系研究相对较少.利用光学显微技术以及Image J统计分析软件,对182份1981'IRRDB野生种质苗期的初生乳管分化进行了研究.结果表明,不同种质叶片以及绿色茎皮中的初生乳管分化能力存在明显差异;而同一种质小叶柄和茎皮中的初生乳管分化能力也并不完全一致.在这182份种质中,小叶柄初生乳管面积比例在0.08%~2.6%范围内,但1%以上的种质数量仅占总数的30.8%;在茎皮中,初生乳管面积百分比在1.3%~13.3%范围内,但7.5%以上的种质数量仅占总数的19.2%,可见,野生种质初生乳管分化能力普遍较低.来源于不同州的野生种质乳管分化能力存在明显差异,由强到弱分别是朗多尼亚州(RO/)、 阿克里州(AC/)、 马托格罗索州(MT/)以及其他非主选区域,其中,朗多尼亚州(RO/)可能更容易筛选到优良的种质.研究结果可为将来种质的引进以及灌木化栽培种质的选育提供依据.%Laticifers in rubber tree are the sole site for natural rubber biosynthesis and storage. The secondary laticifer in the secondary phloem from trunk has been investigated comprehensively, but the primary laticifer in the tender stem and leaf was studied rarely for no relation with the nature rubber production. By using a light microscopy and Image J Software, the primary laticifer differentiation in the seedling among 1821981'IRRDB wild germplasms was analyzed. The results showed that there was obvious difference of primary laticifer differentiation amongst the germplasms and little consistency between the bark and leaf. The area ratio of primary laticifer in petiolule ranged from 0.08%-2.6%, in which more than 1% area ratio only 30.8% of the total germplasms. In the bark of stem, the area ratio of primary laticifer ranged from 1.3%-13.3%, but more than 7.5% area ratio only 19.2% of the total germplasms. Generally, the capacity of primary laticifer differentiation was low. To compare the germplasms derived from differential states found that, the capacity of primary differentiation had obvious discrepancy among states, from strong to weak was RO/, AC/, MT/, and others' sources, in which RO/ may be the best origin for screening excellent germplasms. The results would provide a basis for the introduction of germplasms and breeding of shrubby cultivation.