徳島県立博物館研究報告
Bull. Tokushima Pref. Mus.
No. 24 : 81-82, 2014

【short communication】

A record of a proliferating grass found in Kagawa Prefecture
Yasushi Ibaragi1, Yasuhiro Kikuma2, Osamu Kume3 and Stephen Renvoize4
Key word : Flora, phyllody, proliferation

Spikelets of grasses sometime show incredibly wide

individual plants had strongly curved spikelets（Fig. 1）. Basedmodification. A specimen that was collected in Zentsuji city，on detailed observation，we found that each spikelet had many

Kagawa prefecture，has particularly curved spikelets and itglumes and lemmas，but lacked palea，stamen and pistil in thelooks significantly different from any other recorded grassflorets（Fig. 2）
. Glumes and lemmas are prolonged andspecies from this prefecuture（Fig. 1）. After detailed

twisted.

investigation，this strange grass was identified as a type of

There are three types of malformation that are known frommalformation which frequently occurs in the Poaceae. We

grass family. These are vivipary，proliferation and phyllody

record here this strange malformation，as a reference to avoid（Gould and Shaw 1968）. In the case of vivipary，flowers，

misidentification for floristic work.

lemmas and paleas are transformed into，or replaced by，

The specimen was discovered on a road-side bank along anbulbils or bulblets. Proliferation is when the glumes andexpress-way in Inagi-cho，Zentsuji-city，Kagawa prefecture.

lemmas develop a blade at the distal end and phyllody shows

About ten tussocks were scattered around on arid soil. All

the metamorphosis of the glumes，lemmas and/or paleas into

Fig. 1. A voucher specimen deposited in a herbarium of Tokushima Prefectural Museum（Inagi-cho, Zentsuji-city, Kagawa
prefecture., Y. Kikuma 14 Apr. 2013, TKPM）
Received November 30, 2013 ; accepted December 20, 2013.
1 Tokushima Prefectural Museum, Bunka-no-Mori Park, Tokushima 770-8070, Japan.
2 Inagi-cho 518-3, Zentsuji-city, Kagawa 765-0022, Japan.
3 Ohtakami-machi 78-11, Takamatsu-city, Kagawa 761-8074, Japan.
4 Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK― 81 ―

Fig. 2. Dissected one spikelet. Each spikelet has many glumes and lemmas, while its lacks palea, stamen and pistil in thespikelet.

leaves.

摘The causes for these different modifications are varied and要

香川県で発見されたイネ科小穂形態異常の記録

may result from physical or insect damage ， adverse
environmental conditions and true vivipary. These variations

茨木

occur in Pooideae，Chloridoideae，and Panicoideae，but were

靖1，菊間泰氾2，久米修3，ステファン・レンボイツ4

most frequent in the Pooideae（ Gould and Shaw 1968）.

筆者らの一人菊間は，高速道路法面の植物相調査中，Additionally，it is common for grasses which continue to

見慣れないイネ科植物に気付いた．変わった形態をしてflower at the end of the season to have proliferating spikelets

いたので当初，新産帰化植物と思われたが，詳細な観察（Chapman 1996）.の結果，イチゴツナギ属の一種であると思われる．このえい

Based on our investigation，the sample might be better to be

標本では，小穂の包穎や護穎が異常に多く，一方で内穎，treated as a type of proliferation or phyllody. This means that雌蘂，雄蘂などは全く観察されなかった．これらの穎は，

the spikelets are abnormal and makes it difficult to identify the

いずれもやや伸張しており，ねじれたようになっていた．

species. However，on examining the spikelet in detail we

イネ科植物の小穂がこの様な形状になることは，しばしsuggest that it may be a Poa sp.

ば見られる奇形の一種で，穎が苗条になる無性芽繁殖

ずい（proliferation），ないしは葉のようになる葉化（phyllody）
Specimen examinedに相当することが示唆された．小穂の変形は, 遺伝的なInagi-cho，Zentsuji-city，Kagawa prefecture.（Y. Kikuma 14要素, 昆虫などによる物理的外圧での奇形, その他外部環

Apr. 2013, TKPM-BSP081334 : Fig. 1）

境の影響が原因になる．このような植物を見つけた場合,小穂を解剖すると, 正常な雄蘂や雌蘂などが形成されてI wish to express my sincere thanks to Dr. Hidehisa Koba of J.

いないことが多いので, この点を確認すると良い．

F. Oberlin University for his valuable discussions.

（1 〒770-8070

徳島市八万町文化の森総合公園

2

立 博 物 館， 〒765-0022
3

徳島県

香 川 県 善 通 寺 市 稲 木 町 518-

香川県高松市太田上町 78-11，4 RoyalReferences

3， 〒761-8074

Gould，F. W. and Shaw，R. B. 1968. Grass systematics.

Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK）

Second edition．Texas A&M University press. Texas.
Chapman，G. P. 1996. The Biology of Grasses. CAB
international. Oxon.

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