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''Genlisea margaretae'' is a carnivorous species in the genus ''Genlisea'' (family Lentibulariaceae) native to areas of Madagascar, Tanzania, and Zambia.〔 It has pale bundles of root-like organs up to about 20 cm long under ground that attract, trap, and digest protozoans. These organs are subterranean leaves, which lack chlorophyll. It had been known to possess the smallest known genome of any flowering plant as of 2006, but was later surpassed by the related species ''Genlisea tuberosa''. == Characteristics == ''G. margaretae'' is a perennial herb that forms small, compact rosettes composed of nearly linear leaves about 2 mm wide. Leaves are typically 5-50 mm in length, but most of that length, including the petiole, is hidden beneath the soil. It has no true roots and instead has highly modified subterranean leaves that act as the carnivorous trapping mechanism.〔Taylor, Peter. (1991). ''Carnivorous Plant Newsletter'', 20(1): 20-26.〕 The inflorescences, which can grow to be 20-60 cm tall, emerge from the center of the rosette and produce mauve or violet-colored flowers. Each inflorescence can produce more than 10 flowers on a congested raceme. The upper part of the inflorescences is densely covered with glandular trichomes while the lower part has fewer trichomes and is often glabrous. Individual flowers have rounded upper lips on the corolla instead of being lobed and a relatively straight spur.〔 The genomes of several species in the genus ''Genlisea'' were studied in 2006 along with other members of the Lentibulariaceae family. According to the study, prior to its publication the smallest known angiosperm (flowering plant) genome was that of ''Arabidopsis thaliana'' at 157 Megabase pairs (Mbp). With a diploid chromosome number of around 40 (2n = ca. 40), ''G. margaretae'' held the distinction of having the smallest known angiosperm genome size at 63.4 Mbp, just 0.2 Mbp lower than that of ''Genlisea aurea''. Further research in 2014 found that a related species, ''Genlisea tuberosa'' has a smaller genome size at around 61 Mbp. The smallest individual chromatids from mitotic anaphase are just 2.1 Mbp and therefore have a size smaller than some bacterial chromosomes, such as the approximate 4 Mbp of ''Escherichia coli''. ''G. margaretae'' and ''G. aurea'' also both appear to be polyploid species with the unusual circumstances of having a high chromosome number with extremely small chromosomes. Other species in the genus ''Genlisea'' and the family ''Lentibulariaceae'' have much lower chromosome numbers and larger genome sizes, affirming that one characteristic of this botanic family is rapid molecular evolution. ''G. margaretae'' in particular may be helpful in research aimed at understanding the mechanisms behind genome downsizing.〔Greilhuber, J., Borsch, T., Müller, K., Worberg, A., Porembski, S., and Barthlott, W. (2006). Smallest angiosperm genomes found in Lentibulariaceae, with chromosomes of bacterial size. ''Plant Biology'', 8: 770-777.〕 At least one natural hybrid among the African species that involves ''G. margaretae'' has been described. ''Genlisea margaretae × glandulosissima'' is a product of ''G. margaretae'' and ''G. glandulosissima''.〔Rice, Barry A. (2007). (Old World ''Genlisea'' species ). The Carnivorous Plant FAQ. Accessed 20 May 2007.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Genlisea margaretae」の詳細全文を読む スポンサード リンク
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