[Objective] The aim was to discuss the histological characteristics of ovary development of Varicorhinus gerlachi.[Method] The annual variation of ovary and oocyte development of Varicorhinus gerlachi were observed an...[Objective] The aim was to discuss the histological characteristics of ovary development of Varicorhinus gerlachi.[Method] The annual variation of ovary and oocyte development of Varicorhinus gerlachi were observed and studied by means of histological method.[Result] Ovary development of Varicorhinus gerlachi was divided into 6 stages,and oocyte development had 6 phases,namely oocytes were in original differentiation state in phase Ⅰ,and yolk nucleus could be found obviously in phase Ⅱ.Vacuoles appeared in oocyte in phase Ⅲ,while oocytes differentiated obviously in phase Ⅳ,with the amalgamation of some yolk granules.Eggs formed and oocytes degenerated in phase V and Ⅵ.The development of ovary belonged to non-synchronous and multiple spawning type.In addition,Varicorhinus gerlachi began to spawn in April,and peak period was from May to July.[Conclusion] The study could provide technical parameters for the artificial propagation of Varicorhinus gerlachi.展开更多
Maize ovary development is linked to kernel formation. Soil water deficit results in ovary abortion because of low water potential （ψw） resulting in inhibition of photosynthesis from anthesis to silking stage. Thus...Maize ovary development is linked to kernel formation. Soil water deficit results in ovary abortion because of low water potential （ψw） resulting in inhibition of photosynthesis from anthesis to silking stage. Thus, drought is a key factor causing yield losses in maize, especially near the time of pollination. Earlier studies have indicated that selenium （Se） maintains antioxidative defence systems and enhances sugar and starch accumulation. The effects of Se on maize ovary development were studied in drought stress conditions. Maize ovary development was studied through observations on starch, membrane integrity, fresh weight and dry weight in drought-treated or unstressed glasshouse-grown plants, and crop yield, yield structure, leaf, stem and ear biomass accumulation were also analyzed. Results indicated that Se increased the stress tolerance of the crop, even though ovary abortion was not eliminated by Se treatments under low ψw. Under well-watered control conditions, Se had also negative effects. When the first ear was not succesfully pollinated or the ovaries aborted, the plants developed more ears. Even though these later formed ears did not produce kernels, they significantly increased the dry weight of the plants under water deficit. It could be concluded that The optimal concentration for maize of Se applied through roots is about 0.01 mg kg^-1 （supplied as Na2SeO4） soil or less.展开更多
Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several ord...Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several orders and families.Thus we used nuclear genes of 502 angiosperm species representing 231 families to reconstruct a well supported phylogeny,with resolved relationships for orders and families with previously uncertain placements.Using this phylogeny as a framework,molecular dating supports a Triassic origin of the crown angiosperms,followed by the emergence of most orders in the Jurassic and Cretaceous and their rise to ecological dominance during the Cretaceous Terrestrial Revolution.The robust phylogeny allowed an examination of the evolutionary pattern of fruit and ovary types,revealing a trend of parallel carpel fusions during early diversifications in eudicots,monocots,and magnoliids.Moreover,taxa in the same order or family with the same ovary type can develop either dry or fleshy fruits with strong correlations between specific types of dry and fleshy fruits;such associations of ovary,dry and fleshy fruits define several ovaryfruit"modules"each found in multiple families.One of the frequent modules has an ovary containing multiple ovules,capsules and berries,and another with an ovary having one or two ovules,achenes(or other single-seeded dry fruits)and drupes.This new perspective of relationships among fruit types highlights the closeness of specific dry and fleshy fruit types,such as capsule and berry,that develop from the same ovary type and belong to the same module relative to dry and fleshy fruits of other modules(such as achenes and drupes).Further analyses of gene families containing known genes for ovary and fruit development identified phylogenetic nodes with multiple gene duplications,supporting a possible role of whole-genome duplications,in combination with climate changes and animal behaviors,in angiosperm fruit and ovary diversification.展开更多
The effects of enhanced UV-B radiation on the oogenesis and morpho- anatomical characteristics of the European solitary red mason bee Osmia bicornis L. （Hy- menoptera： Megachilidae） were tested under laboratory con...The effects of enhanced UV-B radiation on the oogenesis and morpho- anatomical characteristics of the European solitary red mason bee Osmia bicornis L. （Hy- menoptera： Megachilidae） were tested under laboratory conditions. Cocooned females in the pupal stage were exposed directly to different doses （0, 9.24, 12.32, and 24.64 kJ/m2/d） of artificial UV-B. Our experiments revealed that enhanced UV-B radiation can reduce body mass and fat body content, cause deformities and increase mortality. Following UV exposure at all 3 different doses, the body mass of bees was all significantly reduced compared to the control, with the highest UV dose causing the largest reduction. Similarly, following UV-B radiation, in treated groups the fat body index decreased and the fat body index was the lowest in the group receiving the highest dose of UV radiation. Mortality and morphological deformities, between untreated and exposed females varied considerably and increased with the dose of UV-B radiation. Morphological deformities were mainly manifested in the wings and mouthparts, and occurred more frequently with an increased dose of UV. Cell death was quantified by the Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） assay （DNA fragmentation） during early stages of oogenesis of O. bicornis females. The bees, after UV-B exposure exhibited more germarium ceils with fragmented DNA. The TUNEL test indicated that in germarium, low doses of UV-B poorly induced the cell death during early development. However, exposure to moderate UV-B dose increased programmed cell death. In females treated with the highest dose of UV-B the vast majority of germarium cells were TUNEL-positive.展开更多
文摘[Objective] The aim was to discuss the histological characteristics of ovary development of Varicorhinus gerlachi.[Method] The annual variation of ovary and oocyte development of Varicorhinus gerlachi were observed and studied by means of histological method.[Result] Ovary development of Varicorhinus gerlachi was divided into 6 stages,and oocyte development had 6 phases,namely oocytes were in original differentiation state in phase Ⅰ,and yolk nucleus could be found obviously in phase Ⅱ.Vacuoles appeared in oocyte in phase Ⅲ,while oocytes differentiated obviously in phase Ⅳ,with the amalgamation of some yolk granules.Eggs formed and oocytes degenerated in phase V and Ⅵ.The development of ovary belonged to non-synchronous and multiple spawning type.In addition,Varicorhinus gerlachi began to spawn in April,and peak period was from May to July.[Conclusion] The study could provide technical parameters for the artificial propagation of Varicorhinus gerlachi.
基金funded by the Finnish Education Funding,the Ningxia Science and Technology Key Projects (20030060)funded by Chinese Scholarship Council,China
文摘Maize ovary development is linked to kernel formation. Soil water deficit results in ovary abortion because of low water potential （ψw） resulting in inhibition of photosynthesis from anthesis to silking stage. Thus, drought is a key factor causing yield losses in maize, especially near the time of pollination. Earlier studies have indicated that selenium （Se） maintains antioxidative defence systems and enhances sugar and starch accumulation. The effects of Se on maize ovary development were studied in drought stress conditions. Maize ovary development was studied through observations on starch, membrane integrity, fresh weight and dry weight in drought-treated or unstressed glasshouse-grown plants, and crop yield, yield structure, leaf, stem and ear biomass accumulation were also analyzed. Results indicated that Se increased the stress tolerance of the crop, even though ovary abortion was not eliminated by Se treatments under low ψw. Under well-watered control conditions, Se had also negative effects. When the first ear was not succesfully pollinated or the ovaries aborted, the plants developed more ears. Even though these later formed ears did not produce kernels, they significantly increased the dry weight of the plants under water deficit. It could be concluded that The optimal concentration for maize of Se applied through roots is about 0.01 mg kg^-1 （supplied as Na2SeO4） soil or less.
基金supported by funds from the National Natural Science Foundation of China(31670209,31770242,and 31970224)China Postdoctoral Science Foundation(2019M661344)+2 种基金funds from the Ministry of Education Key Laboratory of Biodiversity Science and Ecological Engineering and State Key Laboratory of Genetic Engineering at Fudan Universityfunds from the National Top Talent Undergraduate Training Program for outstanding undergraduates and the Wangdao Program for undergraduate research at Fudan Universityfunds from the Eberly College of Science(Department of Biology)and the Huck Institutes for the Life Sciences at the Pennsylvania State University。
文摘Fruit functions in seed protection and dispersal and belongs to many dry and fleshy types,yet their evolutionary pattern remains unclear in part due to uncertainties in the phylogenetic relationships among several orders and families.Thus we used nuclear genes of 502 angiosperm species representing 231 families to reconstruct a well supported phylogeny,with resolved relationships for orders and families with previously uncertain placements.Using this phylogeny as a framework,molecular dating supports a Triassic origin of the crown angiosperms,followed by the emergence of most orders in the Jurassic and Cretaceous and their rise to ecological dominance during the Cretaceous Terrestrial Revolution.The robust phylogeny allowed an examination of the evolutionary pattern of fruit and ovary types,revealing a trend of parallel carpel fusions during early diversifications in eudicots,monocots,and magnoliids.Moreover,taxa in the same order or family with the same ovary type can develop either dry or fleshy fruits with strong correlations between specific types of dry and fleshy fruits;such associations of ovary,dry and fleshy fruits define several ovaryfruit"modules"each found in multiple families.One of the frequent modules has an ovary containing multiple ovules,capsules and berries,and another with an ovary having one or two ovules,achenes(or other single-seeded dry fruits)and drupes.This new perspective of relationships among fruit types highlights the closeness of specific dry and fleshy fruit types,such as capsule and berry,that develop from the same ovary type and belong to the same module relative to dry and fleshy fruits of other modules(such as achenes and drupes).Further analyses of gene families containing known genes for ovary and fruit development identified phylogenetic nodes with multiple gene duplications,supporting a possible role of whole-genome duplications,in combination with climate changes and animal behaviors,in angiosperm fruit and ovary diversification.
基金This work was supported by a Ministry of Science and Higher Education （N N311 298935） and University of Life Sciences （507.511.29） grants to O.W. and in part by a National Science Foundation Grant （EPS-0903787, MSU#269110-151250） grant to N.K. We would like to thank Agnieszka Graclik for her technical support in im- age analysis and preparation.
文摘The effects of enhanced UV-B radiation on the oogenesis and morpho- anatomical characteristics of the European solitary red mason bee Osmia bicornis L. （Hy- menoptera： Megachilidae） were tested under laboratory conditions. Cocooned females in the pupal stage were exposed directly to different doses （0, 9.24, 12.32, and 24.64 kJ/m2/d） of artificial UV-B. Our experiments revealed that enhanced UV-B radiation can reduce body mass and fat body content, cause deformities and increase mortality. Following UV exposure at all 3 different doses, the body mass of bees was all significantly reduced compared to the control, with the highest UV dose causing the largest reduction. Similarly, following UV-B radiation, in treated groups the fat body index decreased and the fat body index was the lowest in the group receiving the highest dose of UV radiation. Mortality and morphological deformities, between untreated and exposed females varied considerably and increased with the dose of UV-B radiation. Morphological deformities were mainly manifested in the wings and mouthparts, and occurred more frequently with an increased dose of UV. Cell death was quantified by the Terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） assay （DNA fragmentation） during early stages of oogenesis of O. bicornis females. The bees, after UV-B exposure exhibited more germarium ceils with fragmented DNA. The TUNEL test indicated that in germarium, low doses of UV-B poorly induced the cell death during early development. However, exposure to moderate UV-B dose increased programmed cell death. In females treated with the highest dose of UV-B the vast majority of germarium cells were TUNEL-positive.
