巴西番石榴微體繁殖之研究

Studies on Micropropagation ofBrazilian Guava (Psidium guineense Sw.)

巴西番石榴具有發展成抗病性根砧或保健產品的潛力。為建立巴西番石榴的微體繁殖技術，以取自盆栽成株之頂梢和莖節兩種培植體測試不同培養基對其增殖及發根的影響。結果顯示，只要解決培植體污染及褐化問題，所測試的培養基皆能使頂梢或莖節順利增殖。在莖節以1/2MS(Murashige and Skoog medium)添加0.1 mg·L-1α-naphthaleneacetic acid (NAA)及1.0 mg·L-1或3.0 mg·L-16-benzyladenine (BA)有較多的每培植體枝梢數(3.3)，而在1.0 mg·L-1BA其枝梢長度有較長的趨勢。頂梢於各處理間則沒有顯著差異。此外，莖節培植體於含0.2% polyvinylpyrrolidone (PVP)的1/2MS培養基單獨添加1.5 mg·L-1BA，其每培植體枝梢數(3.7)有高於其他處理的趨勢，但其枝梢長度則顯著短於其他BA濃度較低的處理。枝梢接著繼代培養至無植物生長調節劑(plant growth regulator, PGR)的MS培養基使枝梢伸長。之後將所誘導的枝梢插穗轉移至無PGR發根培養基。大部分枝梢皆能成功發根，且試管苗能於溫室中馴化。

Brazilian guava has the potential to be developed as disease-resistant rootstocks for graft production or as health supplements for human consumption. To establish a technique of micropropagation for Brazilian guava, two types of explants, including shoot tips and stem nodes harvested from adult potted plants, were tested for the effect of different media on proliferation and rooting. The results show that shoots could be proliferated from shoot tips and stem nodes on all of the tested media once the problems of contamination and browning occurring in explants were solved. Stem nodes in 1/2 MS (Murashige and Skoog medium) supplemented with 0.1 mg·L-1α-naphthaleneacetic acid (NAA) and 1.0 mg·L-1or 3.0 mg·L-16-benzyladenine (BA) had more shoots per explant(3.3) and the shoot length tends to be longer in 1.0 mg·L-1BA. There was no significant difference among treatments for shoot tips. Furthermore, stem nodes cultured in 1/2MS medium containing 1.5 mg·L-1BA and 0.2% polyvinylpyrrolidone (PVP) tends to have higher number of shoots per explant (3.7) than other treatments, while the induced shoot lengths were significantly shorter than treatments with lower concentration of BA. The shoots were sub-cultured to plant growth regulator(PGR)-free MS medium for shoot elongation. Cuttings were made later from induced shoots and transferred into PGR-free rooting medium. Most of the micro-shoot cuttings rooted successfully and the in vitro plantlets can be acclimated in a green house.