白鶴芋屬植物之核型研究

Karyotype Analysis of Spathiphyllum

本實驗之目的為探討收集的白鶴芋屬（Spathiphyllum）種原間的根尖染色體數及核型分析，以協助育種、分類、種原鑑定、種原收集及評估等工作之參考。將十二個白鶴芋品種或種經根尖染色體數檢查的結果顯示，S. 'Max'與S. 'Sensation'品種的染色體數均為2n=45，屬於三倍體，其他品種或種如S. 'Pallas'、S. 'Luna'、S. 'Ceres'、S. 'Stephanie'、S. 'Illusion'、S. 'Vanessa'、S. 'Domino'、S. 'Jetty'、S. 'Petite'、S. cannifolium均為2n=30，屬於二倍體。核型分析結果顯示，染色體以中部著絲點染色體（m）為主，至少具有兩對近中部著絲點染色體（sm），三倍體品種均有4對近中部著絲點染色體（sm），S. 'Max'和S. 'Sensation'的核型公式完全相同，皆是2n=45=33m+12sm。其它品種如S. 'Luna'、S. 'Petite'、S. 'Jetty'和S. 'Stephanie'具有相似核型都為2n=30=24m+6sm，而S. 'Petite'第三條染色體具有次縊痕結構，S. 'Ceres'、S. 'Domino'、S. 'Vanessa'、S. 'Illusion'、S. 'Pallas'和S. cannifolium具有相似核型都為2n=30=26m+4sm，但S.cannifolium第三條染色體具有次縊痕結構。分析最長和最短染色體長度比值介於1.33-1.76之間。核型對稱係數分佈在56.48-59.70%之間，顯示其核型對稱程度高。依據Stebbin（1971）核型分類，S.cannifolium核型類型為1A，其它品種核型類型均為2A。

The purposes of this study are to count root tip chromosome numbers and karyotype analysis of collected Spathiphyllum germplasms. The results showed that S. 'Max' and S. 'Sensation' were both triploid with 2n=45. Other cultivars, including S. 'Pallas', S. 'Luna', S. 'Ceres', S. 'Stephanie', S. 'Illusion', S. 'Vanessa', S. 'Domino', S. 'Jetty', S. 'Petite' and the species S. cannifolium were shown to be diploid with 2n=30. Most genomes are with median type (m) and at least two pairs of submedian (sm) chromosomes, while two triploid cultivars have four pairs of submedian chromosomes. The karyotypes of both S. 'Max' and S. 'Sensation' are 2n=45=33m + 12sm. The karyotypes of other cultivars, including S. 'Luna', S. 'Petite', S. 'Jetty' and S. 'Stephanie' are 2n=30=24m + 6sm, while S. 'Petite' has secondary constriction in the 3rd chromosome. The karyotypes for S. 'Ceres', S. 'Domino', S. 'Vanessa', S. 'Illusion', S. 'Pallas' and S. cannifolium are 2n=30 = 26m + 4sm, while S. cannifolium has a secondary constriction in 3rd chromosome. The ratio for longest and shortest chromosomes is between 1.33 and 1.76. The centromeric terminalization value of chromosomes is 56.48-59.70 %, which shows high symmetry of karyotype in the genus. According to Stebbins (1971), karyotypes of the collected genotypes are either 1A or 2A.