夜來香微嵌紋病毒在植株內之分布及其對病毒檢到之影響

Abstract

夜來香微嵌紋病毒(Tuberose mild mosaic potyvirus, TMMV)為感染夜來香(Polianthes tubosa L.)造成植株葉片及花莖上產生輕微嵌紋病微之致病病毒。利用TMMV之抗血清以酵素連結雙抗體包夾法（double antibody sandwtched ELISA, DAS-ELISA）比較植株中葉、花莖、花朵、球根及根部各組織中病毒濃度之差異時發現TMMV之分布極不均勻，各位中以花莖鞘葉，花莖及新葉之病毒濃度較高。不同葉序之葉片間以內層之新葉病毒濃度高，外層老葉則逐漸遞減。花莖上不同部位之鞘葉中，以下位較成熟之鞘葉病毒濃度較高。不同成熟期花莖之花瓣組織則以愈成熟者之病毒含量較高。另外TMMV在夜來香球根中之分布亦不均勻，比較側芽，鱗葉及基盤組織等三部位後發現側芽及鱗葉之病毒濃度較高，其病毒檢出率約為檢查基盤組織之三倍。故以球根為檢測對象時，應以前二者為取樣標的之檢測結果準確度較高。又取樣時若將每一球根取一側芽提升至取三個側芽混合檢測時，其病毒檢出率可由93%提升至100％。本研究結果可作為檢測夜來香植株或貯藏期球根之TMMV帶毒率之採樣依據，而且證實正確之取樣可增加檢測TMMV病毒之準確性。 Tuberose mild mosaic potyvirus (TMMV) causes mild mosaic symptoms on leaves and flower stems of tuberose (Polianthes tuberosa L.). Detection of TMMV by DAS-ELISA in different parts of tuberose plants, including leaves, flower stems, flower petals, bulbs and roots, revealed that TMMV was unevenly distributed throughout the plant. The highest concentration of TMMV was found in sheath leaves of flower stems, followed by flower stem tissue and young leaves. Concentrations of TMMV were found higher in internal younger leaves and gradually decreased in external older ones. When sheath leaves on flower stems were compared, the larger and more mature sheath leaves consistently demonstated higher TMMV concentrations than those of the smaller and younger ones. When flower buds were tested, TMMV concentrations in petal tissues increased with the age of flower stems. In bulb tissue of tuberose, TMMV was also found distributed unevenly. The virus concentrations in lateral buds and apex scale leaves were significantly higher than those in the core tissue of tuberose bulb, as reflected in the results that successful detection rates of TMMV by sampling from the former two tissues were three times as that from the last one. Although TMMV distributed in different lateral buds unevenly, a detection rate of 100% could be accomplished by sampling and combining tissues of 3 lateral buds from a indexed bulb. These results provide useful information on correct sampling for successful detection of TMMV in tuberose plants or bulbs.