报道了单性木兰(Kmeria septentrionalis Dandy)花的形态发生过程。发现过去一直被认为是雌花条状披针形的"内轮花被片",实际为退化雄蕊,它形态发生的时间与位置均与雄花的雄蕊相同,在成熟结构中仍可见药室残迹,说明单性木兰...报道了单性木兰(Kmeria septentrionalis Dandy)花的形态发生过程。发现过去一直被认为是雌花条状披针形的"内轮花被片",实际为退化雄蕊,它形态发生的时间与位置均与雄花的雄蕊相同,在成熟结构中仍可见药室残迹,说明单性木兰的雌性花是由两性花退化而来。通过与K.duperreana(Pierre)Dandy和Magnolia thailandica Noot.& Chalermglin雌花的比较,发现它们雌花的形态相同,从而得知人们长期以来对此3种植物雌花的认识有误,原一直认为的"内轮花被片"实为退化雄蕊。展开更多
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 belong...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.展开更多
To provide evidence insight into the phylogenetic position of Itea L., we observed floral ontogeny of Itea yunnanensis Franch. under the scanning electron microscope (SEM) for the first time. The floral phyllo...To provide evidence insight into the phylogenetic position of Itea L., we observed floral ontogeny of Itea yunnanensis Franch. under the scanning electron microscope (SEM) for the first time. The floral phyllotaxis is whorled and floral organogenesis follows centripetal pattern. Sepal initiation is in a two_fifths helical order. Petal initiation appears simultaneous, and petals grow at an ordinary rate. The haplostemony of this species arises slightly later than petals but earlier than gynoecium in initiation. Two carpels are free at the early stage of floral ontogeny, but incurve, get closer and become appressed to each other later. Paraffin transverse sections series of gynoecium at anthesis show that two carpels are connate on the ventral side through their entire length. At last, two carpels within the ovary fuse completely, forming two locules separated by a septum, the ventral vascular bundles in two stylar lobes are connected through the parenchyma, and the stigma lobes become fused. These observations are different from those by Bensel and Palser (1975). The gynoecia they described might be not mature, but rather at early developmental stage. We compared floral developmental pattern and floral structure of Itea with its related taxa. In I. yunnanensis petals grow in the way that is different from that of some related taxa such as Saxifragaceae sensu stricto, Hydrangeaceae, Ribes, Brexia . The developing pattern of gynoecium in I. yunnanensis is similar to that of some members in the Saxifragaceae sensu stricto and Hydrangeaceae. The treatment to raise taxonomic rank of Itea from genus to family, Iteaceae, is supported by our results.展开更多
This work aims to study the development of the pericarp of the fruit of Elaeis guineensis Jacq. var. dura. The thickness, the water and the oil contents of its tissues are evaluated every two weeks, from pollination t...This work aims to study the development of the pericarp of the fruit of Elaeis guineensis Jacq. var. dura. The thickness, the water and the oil contents of its tissues are evaluated every two weeks, from pollination to the maturity of the fruit. The development of the oil palm fruit takes 5.5 months. The endocarp reaches its maximum thickness at the 70th DPP （day post-pollination）, with a water content of 72%. It then starts its dehydration, while sclerifying. It therefore isolates the seed at start and later protects it. The mesocarp is visible at anthesis and its water content is close to 92%. From the 100th DPP, it begins a continuous dehydration associated, from the 130th DPP, with an active lipids biosynthesis. Ultimately, the pericarp of the oil palm fruit fulfills both functions, namely to protect the seed by early sclerification of the endocarp and ensure the dissemination of the species by the high oil content of the mesocarp. A comparative anatomy of the pericarp tissues of the three genotypes.of E. guineensis Jacq., during the first three weeks of fruit development, will enhance the understanding of the primary effect of sh gene.展开更多
Plum is the major fruit species in the area of North Montenegro. Over a long period of growing in this region, autochthonous cultivars adapted, and have been achieving satisfactory results, despite poor growing condit...Plum is the major fruit species in the area of North Montenegro. Over a long period of growing in this region, autochthonous cultivars adapted, and have been achieving satisfactory results, despite poor growing conditions. A study conducted over a period of three years in a North Montenegro region included in situ identification of autochthonous plum cultivars. Observation and recording of their phenological and pomological traits were performed using International Board for Plant Genetic Resources （IBPGR） and International union for the Protection of New Varieties of plants （UPOV） methodologies. Eighteen cultivars derived from Prunusdomestica L. and two cultivars derived from P. insititia L. were identified. Flowering started between March 26th and April 12th and fruit ripening between 13th of July （Petrovaca） and 18th September （Trnovaca）. Fruit weight ranged from 6.65 g ± 0.235 g to 53.88 g ± 0.654 g respectively and stone weight from 0.16 g ±0.003 g to 2.20 g ± 0.711 g. The cultivars were classified as being extremely small in terms of fruit size, except for cvs Crvenadurgulja （big fruit size）. Rounded fruit shape and light green ground color were dominant. Skin color ranged from amber to black. Yellow green was a dominant flesh color and medium flesh firmness predominated. The fruits of the above cultivars could be processed, particularly into plum brandy, or they could be used fresh or dried. The selected plum cultivars can be used in breeding programmes, as rootstocks as well as in further disease related systematic studies under field and laboratory conditions.展开更多
The Tarim Basin,Xinjiang,China,a region important to the walnut industry,is affected by frequent heavy dust storms.Dust,including micro-particles(diameter<10μm),covers the surface of the walnut tree,thereby changi...The Tarim Basin,Xinjiang,China,a region important to the walnut industry,is affected by frequent heavy dust storms.Dust,including micro-particles(diameter<10μm),covers the surface of the walnut tree,thereby changing the surface-atmosphere interface microenvironment,which,in turn,influences the exterior and interior structure of the tree.Dust storms occur in spring and summer,during the flowering period of walnut,which is the key developmental stage leading to fruit formation.This study investigated the effects of dust on female flowers,male flowers,and the pollination of walnut.The morphological changes in the stigma during pollination were recorded.Stigma receptivity was studied via the benzidine–H2O2 method.Morphological features of the female floral organs and pollen were investigated using scanning electron microscopy.Pollen germination and pollen tube growth were examined by fluorescence microscopy.The results showed that dust had a significant inhibitory effect on male and female flowers,resulting in decreased catkin growth,reduced pollen viability(pollen viability was 20.13%),blocked pollen apertures,a reduced pollen germination rate on the stigma,and increased time needed for pollen tube appearance.Dust also had an inhibitory effect on stigma length and receptivity of female walnut flowers,with the length of the walnut stigma being reduced by 0.25~0.80 mm during the flowering process.In addition,there was decreased stigma mucus,resulting in stigma atrophy,decreased amount of pollen on the stigma,weakened stigma receptivity,and accelerated drying of female flowers.In the Tarim Basin,walnut flowering occurd at the same time as dust storms do,which had a negative impact on the floral organ,flowering and pollination of walnut.展开更多
文摘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.
文摘To provide evidence insight into the phylogenetic position of Itea L., we observed floral ontogeny of Itea yunnanensis Franch. under the scanning electron microscope (SEM) for the first time. The floral phyllotaxis is whorled and floral organogenesis follows centripetal pattern. Sepal initiation is in a two_fifths helical order. Petal initiation appears simultaneous, and petals grow at an ordinary rate. The haplostemony of this species arises slightly later than petals but earlier than gynoecium in initiation. Two carpels are free at the early stage of floral ontogeny, but incurve, get closer and become appressed to each other later. Paraffin transverse sections series of gynoecium at anthesis show that two carpels are connate on the ventral side through their entire length. At last, two carpels within the ovary fuse completely, forming two locules separated by a septum, the ventral vascular bundles in two stylar lobes are connected through the parenchyma, and the stigma lobes become fused. These observations are different from those by Bensel and Palser (1975). The gynoecia they described might be not mature, but rather at early developmental stage. We compared floral developmental pattern and floral structure of Itea with its related taxa. In I. yunnanensis petals grow in the way that is different from that of some related taxa such as Saxifragaceae sensu stricto, Hydrangeaceae, Ribes, Brexia . The developing pattern of gynoecium in I. yunnanensis is similar to that of some members in the Saxifragaceae sensu stricto and Hydrangeaceae. The treatment to raise taxonomic rank of Itea from genus to family, Iteaceae, is supported by our results.
文摘This work aims to study the development of the pericarp of the fruit of Elaeis guineensis Jacq. var. dura. The thickness, the water and the oil contents of its tissues are evaluated every two weeks, from pollination to the maturity of the fruit. The development of the oil palm fruit takes 5.5 months. The endocarp reaches its maximum thickness at the 70th DPP （day post-pollination）, with a water content of 72%. It then starts its dehydration, while sclerifying. It therefore isolates the seed at start and later protects it. The mesocarp is visible at anthesis and its water content is close to 92%. From the 100th DPP, it begins a continuous dehydration associated, from the 130th DPP, with an active lipids biosynthesis. Ultimately, the pericarp of the oil palm fruit fulfills both functions, namely to protect the seed by early sclerification of the endocarp and ensure the dissemination of the species by the high oil content of the mesocarp. A comparative anatomy of the pericarp tissues of the three genotypes.of E. guineensis Jacq., during the first three weeks of fruit development, will enhance the understanding of the primary effect of sh gene.
文摘Plum is the major fruit species in the area of North Montenegro. Over a long period of growing in this region, autochthonous cultivars adapted, and have been achieving satisfactory results, despite poor growing conditions. A study conducted over a period of three years in a North Montenegro region included in situ identification of autochthonous plum cultivars. Observation and recording of their phenological and pomological traits were performed using International Board for Plant Genetic Resources （IBPGR） and International union for the Protection of New Varieties of plants （UPOV） methodologies. Eighteen cultivars derived from Prunusdomestica L. and two cultivars derived from P. insititia L. were identified. Flowering started between March 26th and April 12th and fruit ripening between 13th of July （Petrovaca） and 18th September （Trnovaca）. Fruit weight ranged from 6.65 g ± 0.235 g to 53.88 g ± 0.654 g respectively and stone weight from 0.16 g ±0.003 g to 2.20 g ± 0.711 g. The cultivars were classified as being extremely small in terms of fruit size, except for cvs Crvenadurgulja （big fruit size）. Rounded fruit shape and light green ground color were dominant. Skin color ranged from amber to black. Yellow green was a dominant flesh color and medium flesh firmness predominated. The fruits of the above cultivars could be processed, particularly into plum brandy, or they could be used fresh or dried. The selected plum cultivars can be used in breeding programmes, as rootstocks as well as in further disease related systematic studies under field and laboratory conditions.
文摘The Tarim Basin,Xinjiang,China,a region important to the walnut industry,is affected by frequent heavy dust storms.Dust,including micro-particles(diameter<10μm),covers the surface of the walnut tree,thereby changing the surface-atmosphere interface microenvironment,which,in turn,influences the exterior and interior structure of the tree.Dust storms occur in spring and summer,during the flowering period of walnut,which is the key developmental stage leading to fruit formation.This study investigated the effects of dust on female flowers,male flowers,and the pollination of walnut.The morphological changes in the stigma during pollination were recorded.Stigma receptivity was studied via the benzidine–H2O2 method.Morphological features of the female floral organs and pollen were investigated using scanning electron microscopy.Pollen germination and pollen tube growth were examined by fluorescence microscopy.The results showed that dust had a significant inhibitory effect on male and female flowers,resulting in decreased catkin growth,reduced pollen viability(pollen viability was 20.13%),blocked pollen apertures,a reduced pollen germination rate on the stigma,and increased time needed for pollen tube appearance.Dust also had an inhibitory effect on stigma length and receptivity of female walnut flowers,with the length of the walnut stigma being reduced by 0.25~0.80 mm during the flowering process.In addition,there was decreased stigma mucus,resulting in stigma atrophy,decreased amount of pollen on the stigma,weakened stigma receptivity,and accelerated drying of female flowers.In the Tarim Basin,walnut flowering occurd at the same time as dust storms do,which had a negative impact on the floral organ,flowering and pollination of walnut.
