培植體型態和培養方式對植草癒傷組織和植體再生的影響

The Effects of Explant Type and Culture Conditions on Turfgrass Callus Initiation and Plant Regeneration

植草（Turfgrass）乃定義為一種緊密連接的地被植物，並且可以忍受割草，以及人、車的踐踏。利用生物技術來改進植草的遺傳特性，是最近幾年才發展的研究領域。本試驗中，癒傷組織可以分別從聖奧古斯汀草的'Texas Common'，'Seville'，和'Floratum'品種；百慕達草'Tifway Ⅱ，品種取其單節為培植體，和聖奧古斯汀草'Texas Common'，品種取其幼花穗為培植體，以及匍匐性麗糠穗草'Seaside'品種；朝鮮草以及百慕達草的種子中來誘導。MS培養基加上每公升30克的蔗糖以及每公升中1.5或10毫克的2,4-D可以誘發癒傷組織。2,4-D比NAA和picloram更適合癒傷組織的誘導。蔗糖的濃度對癒傷組織的生長影響不大。在以'Seaside'的種子和'Texas Common'的幼花穗為培植體所做的實驗中發現，將培植體培養於固體培養基比培養於液體紙橋上，更有利於癒傷組織的誘導。由種子培植體誘導的癒傷組織初期只有水浸狀的結構出現，但是在繼代培養1到2次之後結構逐漸密實，並且再生出植體。

Turfgrasses form a more or less contiguous ground cover that persists under regular mowing and traffic. Tissue culture of turfgrass is a recently expanding research area that may be used for improving the genetic desirability of turf grass. In this study, callus was induced from nodal explants of St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] 'Texas Common', 'Seville', and 'Floratum', and bermudagrass (Cynodon L. C. Rich) 'Tifway Ⅱ', from unemerged inflorescences of 'Texas Common', and from seeds of creeping bentgrass (Agrostis palustris Huds.) 'Seaside'; zoysiagrass (Zoysia japonica Steud.), and common bermudagrass (Cynodon dactylon (L.) Pers.) in Murashige-Skoog (MS) medium with 30g 1-1 sucrose and 1,5, or 10 mg 1-1 2,4-dichlorophenoxyacetic acid (2,4-D). The growth regulator 2,4-D (65.8%) induced callus at a higher frequency than α -naphthaleneacetic acid (NAA) (47.2%) and picloram (3.4%) from immature inflorescences of 'Texas Common', and sucrose concentrations between 60 g 1-1 (10.0 mm²) and 20 g 1-1 (8.6 mm²) produced no significant difference in growth rate. The rate of callus initiation was higher on agar solidified medium compared to on filter paper bridges from seeds of 'Seaside' and the immature inflorescence explants of 'Texas Common'.