CAJ | 학술논문

在扫描电镜下对台闽苣苔 (T. oldhamii (Hemsl.) Solereder)进行了花部器官形态发生的观察,为探索该类群的个体发育、类群间的系统发育关系和进化趋势提供依据.研究发现该属植物萼片、花冠和雄蕊发生式样均为五数花类型,它们各自来源于花原基上分化出来的萼片原基、花冠原基和雄蕊原基;花冠与雄蕊的两侧对称性与花冠上唇生长稍快和退化雄蕊原基发育迟滞相关;萼片原基的发生和发育的顺序是不一致的:萼片原基发生的式样为近轴中原基-远轴2原基-2侧原基,发育式样则为近轴中萼片-2侧萼片-远轴2萼片,花蕾时为镊合状排列.花冠裂片原基的发生和发育式样是一致的,即远轴中裂原基(下唇中裂片)-远轴2侧裂原基(下唇2侧裂片)-近轴2裂原基(上唇2裂片).花蕾期卷迭式为覆瓦状排列,从外向内:下唇中裂片-下唇2侧裂片-上唇2裂片或下唇2侧裂片-上唇2裂片-下唇中裂片.雄蕊原基与花冠裂片原基互生,前方雄蕊原基在发生上稍迟于后方雄蕊原基,后者与退化雄蕊原基几乎同时发生,但较小,并与近轴心皮(或柱头上唇)对生.将该属与玄参科(Scrophulariaceae)的地黄属( Rehmannia )、苦苣苔科(Gesneriaceae)的异叶苣苔属( Whytockia)和尖舌苣苔属(Rhynchoglossum )的花部器官比较发现,这四个属在这方面呈现出多样性和交叉.过去一直按子房室数和胎座类型划分玄参科(子房2室、中轴胎座)和苦苣苔科(子房1室、侧膜胎座)这一做法受到了质疑.
재소묘전경하대태민거태 (T. oldhamii (Hemsl.) Solereder)진행료화부기관형태발생적관찰,위탐색해류군적개체발육、류군간적계통발육관계화진화추세제공의거.연구발현해속식물악편、화관화웅예발생식양균위오수화류형,타문각자래원우화원기상분화출래적악편원기、화관원기화웅예원기;화관여웅예적량측대칭성여화관상진생장초쾌화퇴화웅예원기발육지체상관;악편원기적발생화발육적순서시불일치적:악편원기발생적식양위근축중원기-원축2원기-2측원기,발육식양칙위근축중악편-2측악편-원축2악편,화뢰시위섭합상배렬.화관렬편원기적발생화발육식양시일치적,즉원축중렬원기(하진중렬편)-원축2측렬원기(하진2측렬편)-근축2렬원기(상진2렬편).화뢰기권질식위복와상배렬,종외향내:하진중렬편-하진2측렬편-상진2렬편혹하진2측렬편-상진2렬편-하진중렬편.웅예원기여화관렬편원기호생,전방웅예원기재발생상초지우후방웅예원기,후자여퇴화웅예원기궤호동시발생,단교소,병여근축심피(혹주두상진)대생.장해속여현삼과(Scrophulariaceae)적지황속( Rehmannia )、고거태과(Gesneriaceae)적이협거태속( Whytockia)화첨설거태속(Rhynchoglossum )적화부기관비교발현,저사개속재저방면정현출다양성화교차.과거일직안자방실수화태좌류형화분현삼과(자방2실、중축태좌)화고거태과(자방1실、측막태좌)저일주법수도료질의.
Floral organogenesis of Titanotrichum oldhamii (Hemsl.) Soler., the only species in the genus and endemic to East Asia, was observed under SEM. We found that the development of calyx, corolla and androecium belongs to pentamerous pattern. They come respectively from primordia of calyx, corolla and androecium, and all differentiated from the flower primordium. The zygomorphism of corolla and androecium is derived from quicker growth of the upper lip of corolla and delay in development of the staminode. Initiation of sepal primordia and their development are not consistent in order; the order of initiation is from adaxial central primordium, abaxial two primordia and finally lateral two primordia, while the order of development is first adaxial central sepal, lateral two and finally abaxial two. Sepals are valvate in flower bud. Initiation of corolla lobe primordia and their development are consistent in order, i.e. first abaxial central lobe (central lobe of the lower lip), lateral two (lateral two lobes of the lower lip) and finally adaxial two (two lobes of the upper lip). The aestivation of corolla is imbricate, and the order from outside to inside is the central lobe of the lower lip, lateral two of the lower lip, and finally two of the upper lip or lateral two lobes of the lower lip, two of the upper lip and central one of the lower lip. Stamen primordia are alternate to the corolla lobe primordia, with the anterior two primordia later than the posterior two in initiation; staminode primordium is simultaneous with the posterior two in initiation, but smaller, and opposite to the adaxial carpel (upper lip of stigma). Compared to the patterns of floral organogenesis of Rehmannia (Scrophulariaceae), Whytockia and Rhynchoglossum (Gesneriaceae), the present authors found that the floral organogenesis is diverse and does not form two distinct patterns among these four genera. Based on the results we tend to consider that the conventional demarcation between the Scrophulariaceae and Gesneriaceae using number of ovary locules (two vs one) and placentation (axile vs parietal) is questionable.