An interspecific hybrid F1 of Cucumis hystrix Chakr. x Cucumis sativus L. (NC4406) was used to establish the developmental sequence and to characterize the male and female gametophytes at cytological level for furth...An interspecific hybrid F1 of Cucumis hystrix Chakr. x Cucumis sativus L. (NC4406) was used to establish the developmental sequence and to characterize the male and female gametophytes at cytological level for further understanding of the phylogenic relationship and the mechanism of fertility or sterility in the interspecific hybrid F1 The development of male and female gametophytes was studied through meiotic analysis and paraffin section observation technique, respectively. Meanwhile, the fertility level was assessed through hybrid F1 backcrossing to cultivated cucumber 4406. Variable chromosome configurations were observed in the pollen mother cells (PMCs) of hybrid F1 at metaphase Ⅰ , e.g., univalents, bivalents, trivalents, quadravalents, etc. At anaphase Ⅰ and Ⅱ, chromosome lagging and bridges were frequently observed as well, which led to the formation of polyads and only a partial number of microspores could develop into fertile pollen grains (about 23.3%). Observations of the paraffin sections showed numerous degenerated and abnormal embryo sacs during the development of female gametophytes, and only 40% of the female gametophytes could develop into normal eight-nuclear megaspore. On an average, 22.8 and 6.3 seeds per fruit could be obtained from the reciprocal backcross. The interspecific hybrid F1 of C. hystrix x NC4406 was partially fertile; however, the meiotic behaviors of hybrid F1 showed a high level of intergenomic recombination between C. hystrix and C. sativus chromosomes, which indicated that it plays an important role for introgression of useful traits from C. hystrix into C. sativus.展开更多
This study on the effects of ultrasonic treatment on female gametophytes of Laminariajaponica showed that:1. Ultrasonic treatment had shortening effect on filaments of female gametophytes. Within certainperiod of time...This study on the effects of ultrasonic treatment on female gametophytes of Laminariajaponica showed that:1. Ultrasonic treatment had shortening effect on filaments of female gametophytes. Within certainperiod of time, the average length of filamentous female gametophytes was shortened.2. Ultrasonic treatment had emptying effect on cells. The number of empty cells increased with timeof treatment. Ultrasonic treatment had harmful effect on cells.3. Ultrasonic treatment could break down cell walls. The combination of frequency of 20 kHz, out-put of 15 W, 40 s and 60 s of treatment was best for this purpose. After ultrasonic treatment, the regner-ation of female gametophytes into sporophytes was effected. Female gametophytes could not recover aftertoo long period of treatment.展开更多
The objective of this study was to examine the eff ects of temperature and light intensity on growth of female gametophytes of Eisenia bicyclis and Ecklonia cava and responses of these female gametophytes to Fe additi...The objective of this study was to examine the eff ects of temperature and light intensity on growth of female gametophytes of Eisenia bicyclis and Ecklonia cava and responses of these female gametophytes to Fe addition and daylength. Female gametophytes of each species were cultured at four temperatures (10, 15, 20, and 25°C) and under a combination of four light intensities (10, 20, 40, and 80 μmol photons/(m^2 ·s)) with two temperatures (15 and 20°C for E i . bicyclis;20 and 25°C for E c . cava ) to clarify their optimal growth conditions. Growth and maturation of female gametophytes of these two species under a combination of five Fe-EDTA concentrations (0, 1, 2, 4, and 8 μmol/L) and three daylengths (10, 12, and 14 h) were also examined. The growth of E i . bicyclis gametophyte was maximal at approximately 15–20°C, 20 μmol photons/(m^2 ·s), Fe-EDTA concentration of 8 μmol/L and daylengths of 12–14 h. While E c . c ava gametophytes showed optimal growth at approximately 20–25°C, 20 μmol photons/(m^2 ·s), Fe- EDTA concentration of 8 μmol/L and daylength of 14 h. Maturation of gametophytes was enhanced at Fe-EDTA concentration of 4 μmol/L for E i . bicyclis and at 2 μmol/L for E c . c ava . In conclusion, optimal growth temperatures and Fe-EDTA concentrations for maturation of E i . bicyclis and E c . c ava gametophytes were diff erent. Higher optimal growth temperature for E c . c ava gametophytes may contribute to its wider geographical distribution compared to E i . bicyclis which has restricted habitats in Korea. This suggests that addition of Fe ion could be used to recover beds of these two species in barren grounds of Korea.展开更多
Abstract: Inter-simple sequence repeat (ISSR) analysis was used to assess genetic diversity among 10 pairs of male and female Laminaria gametophytes. A total of 58 amplification loci was obtained from 10 selected ISSR...Abstract: Inter-simple sequence repeat (ISSR) analysis was used to assess genetic diversity among 10 pairs of male and female Laminaria gametophytes. A total of 58 amplification loci was obtained from 10 selected ISSR primers, of which 34 revealed polymorphism among the gametophytes. Genetic distances were calculated with the Dice coefficient ranging from 0.006 to 0.223. A dendrogram based on the unweighted pair-group method arithmetic (UPGMA) average showed that most male and female gametophytes of the same species were clustered together and that 10 pairs of gametophytes were divided into four groups. This was generally consistent with the taxonomic categories. The main group consisted of six pairs of gametophytes, which were selected from Laminaria japonica Aresch. by intensive inbreeding through artificial hybridization. One specific marker was cloned, but was not converted successfully into a sequence characterized amplified region (SCAR) marker. Our results demonstrate the feasibility of applying ISSR markers to evaluate Laminaria germplasm diversities.展开更多
Dear Editor, Environmental arsenic (As) contamination of both soil and water systems is a worldwide problem, and As can enter the human food chain through contaminated agricultural products and drinking water and cont...Dear Editor, Environmental arsenic (As) contamination of both soil and water systems is a worldwide problem, and As can enter the human food chain through contaminated agricultural products and drinking water and contribute to the development of lung.展开更多
Carbonic anhydrase(CA)was considered to be an important component of carbon concentrating mechanism(CCM)of algae.It was an inducible enzyme.Environmental factors,especially dissolved inorganic carbon and pH,were known...Carbonic anhydrase(CA)was considered to be an important component of carbon concentrating mechanism(CCM)of algae.It was an inducible enzyme.Environmental factors,especially dissolved inorganic carbon and pH,were known to affect CA activity.Effects of inorganic carbon(CO_(2)and HCO_(3)^(-))and pH on CA activity of gametophytes of Saccharina japonica were evaluated in this study.Under high-CO_(2)condition(3%CO_(2)),the activity of external CA(C_(Aext))was significantly decreased(P<0.05)from 33.92 REA/g FW to 27.69 REA/g FW.In contrast,the internal CA(CA_(int))and total CA activities were elevated significantly(p<0.01)from 36.83 REA/g FW to 48.80 REA/g FW,and from 70.75 REA/g FW to 76.49 REA/g FW,respectively.Addition of an appropriate concentration of HCO_(3)^(-)to the medium,CA_(int)and total CA activities were promoted significantly,although the activity of C_(Aext)was inhibited significantly(P<0.05).In higher HCO_(3)^(-)concentration(up to 1680 mg/L),the activity of CA_(int)was promoted to 60.81REA/g FW,which was twice that of the control.Higher activities of CA_(int)and total CA were induced at low pH.At pH 6.0,the highest activities of CA_(int)(110.85 REA/g FW)and total CA(128.17 REA/g FW)were induced.However,at pH 9.0,the activities of CA_(int)and total CA were reduced to the lowest of 23.31REA/g FW and 42.19 REA/g FW,respectively.This is the first report about the successful detection of C_(Aext)activity of gametophytes of S.japonica.The results would provide data for the analysis of Ci acquisition and transport mechanism in S.japonica gametophytes.展开更多
The life cycle of seaweed Laminaria japonica involves a generation alternation between diploid sporophyte and haploid gametophte. The expression of foreign genes in sporophte has been proved. In this research, the rec...The life cycle of seaweed Laminaria japonica involves a generation alternation between diploid sporophyte and haploid gametophte. The expression of foreign genes in sporophte has been proved. In this research, the recombinant expression in gametophyte was investigated by particle bombardment with the rt-PA gene encoding the recombinant human tissue-type plasminogen activator (Reteplase), which is a thrombolytic agent for acute myocardial infarction (AMI). Transgenic gametophytes were selected by their resistance to herbicide phosphiothricin (PPT), and proliferated in an established bubble column photo-bioreactor. According to the results from quantitative ELISA, Southern blotting, and fibrin agarose plate assay (FAPA) for bioactivity, it was showed that the rt-PA gene had been inte-grated into the genome of gametophytes of L. japonica, and the expression product showed the ex-pected bioactivity, implying the proper post-transcript modification in haploid gametophyte.展开更多
Effects of various concentrations of two heavy metals, namely Cd and Cu, on gametophytes of Laminariajaponica Aresch were determined by recording morphological changes of gametophytes, determining pH values and the he...Effects of various concentrations of two heavy metals, namely Cd and Cu, on gametophytes of Laminariajaponica Aresch were determined by recording morphological changes of gametophytes, determining pH values and the heavy metal content of the culture solution, calculating the germination rate of sporophytes, and observing heavy metal (Cd) distribution using a fluorescence microscope. The results showed that heavy metals damaged the gametophytes, and were even lethal, and that the higher the concentration of heavy metal ions, the greater the injury to gametophytes. Gametophytes could not survive in culture solutions containing more than 100 mg/L Cd and 50 mg/L Cu and were only able to survive in culture solution containing a mixture of Cd and Cu up to a concentration of 10 mg/L, which indicates that gametophytes have a higher tolerance to Cd than Cu and that multiple heavy metal ions in solution markedly aggravate the damage to gametophytes compared with individual heavy metal ions. With increases in the concentration of the heavy metal, the burgeoning rate of sporophytes decreased acutely, and solutions containing multiple heavy metal ions caused even more marked harm to sporophytes than solutions containing a single heavy metal ion, because most sporophytes died in mixed solutions. The pH value of the culture medium dropped immediately at the beginning (the first day) of treatment, increased over the following days, and then decreased again. The pH of culture media containing multiple heavy metal ions showed greater variation than media containing a single heavy metal ion, with the extent of the decrease in pH of culture media containing multiple ions being greatest during the last period of the experiment. With increases in the concentration of heavy metals, the capacity of gametophytes to accumulate these ions increased. The blue fluorescent light emitted by the Cd-and Cd-binding protein complex existing in gametophytes in media containing different concentrations of Cd showed clearly the distribution of the ion in gametophytes and the results obtained were consistent with distribution determined using other methods. All results of the present study showed that gametophytes of L. japonica play a remarkable role as heavy metal decontaminators, especially with regard to Cd.展开更多
Long non-coding RNAs(lncRNAs)regulate a variety of biological processes,including sexual reproduction and differentiation.Saccharina japonica,a commercially important brown alga in China,shows remarkable sexual dimorp...Long non-coding RNAs(lncRNAs)regulate a variety of biological processes,including sexual reproduction and differentiation.Saccharina japonica,a commercially important brown alga in China,shows remarkable sexual dimorphism in haploid gametophytes.The sex of Saccharina japonica gametophytes is determined by UV sexual system.However,no results have been reported on the lncRNAs involved in the sex-related gene regulation of S.japonica.This study identified a number of lncRNAs and assessed their expression levels in male and female gametophytes.Among them,a total of 405 lncRNAs and 211 mRNAs showed differential expressions.Furthermore,the functions of target genes of differentially expressed lncRNAs(DELs)differed from those of differentially expressed genes(DEGs),suggesting that lncRNA may interact with other functional proteins,in addition to DEGs,to involve sex regulation in S.japonica.There were 32 and 90 potential cis-regulatory and trans-regulatory interactions between DELsDEGs,respectively.Five of these lncRNAs(LNC_002974,LNC_021059,LNC_038466,LNC_051584,and LNC_027400)interacted with putative male sex determination region(SDR)genes,suggesting that they act as regulators in gametophytes'sex regulation potentially.Findings from this study contribute to our understanding of the roles of lncRNAs in sex differentiation and lay the foundation for functional studies of candidate lncRNAs in the future.展开更多
Abstract Ulva linza is one of the species that causes green tides in the Yellow Sea,China.Due to the diffi culties in chromosomal preparation,the large numbers of chromosomes,and their relatively small sizes,there hav...Abstract Ulva linza is one of the species that causes green tides in the Yellow Sea,China.Due to the diffi culties in chromosomal preparation,the large numbers of chromosomes,and their relatively small sizes,there have been no reported studies on Ulva macroalgae chromosomes.The karyotypes and chromosomes in U.linza were observed after a series of treatments.The chromosomes were pretreated with 0.1%colchicine for 12 h and then mixed with enzymes.The samples were dropped from 30 cm height onto glass slides,which spread out the surface coat.These pretreatments were the optimal chromosomes preparation treatments.The prepared chromosomes were stained with 4',6-diamidino-2-phenylindole(DAPI),which is a fl uorescent probe sensitive and specifi c to DNA.The chromosome number in the haploid male and female gametophytes was n=9,and was 2 n=18 in the diploid sporophytes.The female gametophyte chromosomes were between 0.804 and 2.292μm in size,the male gametophyte chromosomes were between 0.917 and 2.916μm,and the sporophyte chromosomes were between 0.912 and 2.167μm.The relative sizes of the chromosomes were used to analyze the karyotypes of the female and male gametophyte chromosomes.The results provide a solid foundation for the basic technique that can be used to localize molecular markers of Ulva chromosomes.展开更多
Unicellular gametophytes of Undaria pinnatifida (Harv.) Sur. were isolated in Qingdao, P. R. China in April 1993 and in Tokushima, southem Japan in March 1995. Diferent intraspecific crossings by using unicellular mal...Unicellular gametophytes of Undaria pinnatifida (Harv.) Sur. were isolated in Qingdao, P. R. China in April 1993 and in Tokushima, southem Japan in March 1995. Diferent intraspecific crossings by using unicellular male and female gametophytes were successfully undertaken in Sept. of 1995 in Qingdao.Sporophytes were transplanted to two different locations for open an cultivation. One was at Zhanqiao (ZQ) Bay where the water current was slower than that of another location - Taipingjiao(TPJ). A total of218 adult sporophytes were harvested on January 12 and 18 from TPJ and ZQ repectively. For eacncombination, 10 sporophytes un cultivated. Analysis of the mprpholgical characteristics of adult spprophytes indicated that the longest length between two bases of the serration of pinnate bldes (W2) is a morphological characteristic that can be transferred from the parent plant to the next generations regardless of environmental variations. There was evidence that W2 was apparently determined by sex-linked factors, i.e, by male parental grametophyte.. Sporophytes from certain crossing combinations showed more vigorous growth than those from other crossing combinations. It is therrfore possible to select grametophyte strains which can be used as parental gametophytes for the seeding production of sporophytes with more vigorous growth within shorter cultivation period. The morphology of hybrids from a Qingdao strain and a Tokushima cultivated strain resembled that of both parental plants in frond feaures (wrinkled or smooth) and W2. Sporophyll formation also varied with strains. The fact that adult sporophytes resulting from the same crossing combinations have identical morphological characteristics under the same environmental conditions indicates the possibility of a new way to select strains which are expected to be ideal for commerical production by purposely selecting, propagating, and seeding unicellular gametophytes for sporeing production through freeliving techniques of gametophytes.展开更多
Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery effort...Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery efforts.In this study, we took Athyrium brevifrons as an example, predicted its suitable habitat using a Maxent model with 67 occurrence data and nine environmental variables in Northeast China.The area under the curve(AUC) value of independent test data, as well as the comparison with specimen county areal distribution of A.brevifrons exhibited excellent predictive performance.The type of environmental variables showed that precipitation contributed the most to the distribution prediction, followed by temperature and topography.Percentage contribution and permutation importance both indicated that precipitation of driest quarter(Bio17) was the key factor in determining the natural distribution of A.brevifrons, the reason could be proved by the fern gametophyte biology.The analysis of high habitat suitability areas also showed the habitat preference of A.brevifrons: comparatively more precipitation and less fluctuation in the driest quarter.Changbai Mountains, covering almost all the high and medium habitat suitability areas, provide the best ecological conditions for the survival of A.brevifrons, and should be considered as priority areas for protection and restoration of the wild resource.The potential habitat suitability distribution map could provide a reference for the sustainable development and utilisation of A.brevifrons resource, and Maxent modelling could be valuable for conservation management planning for lycophytes and ferns in Northeast China.展开更多
After continuous breeding gametophyte of Laminaria, then breaking protonema, heterosis seedling is got by bilineal hybridization. The result shows that the weight-increasing rate of female and male gametophyte clone c...After continuous breeding gametophyte of Laminaria, then breaking protonema, heterosis seedling is got by bilineal hybridization. The result shows that the weight-increasing rate of female and male gametophyte clone cells are 14.03% and 13.87%, after 16 d crossbreeding, the rate of ovulation is up to100%; the length of juvenile sporophyte after 40 d breeding is 2-3 cm. By farming on the sea, a hybrid combination is primarily screened.展开更多
In China, the total annual production of cultured Laminaria japonica reached half million tons in dry weight there few years. The routine sporeling culture technique conducted in the greenhouse took at least three and...In China, the total annual production of cultured Laminaria japonica reached half million tons in dry weight there few years. The routine sporeling culture technique conducted in the greenhouse took at least three and half months. In such a case, sometimes the sporelings died within a few days due to destructive diseases. In Order to overcome the mentioned problems, a new sporeling culture technique, the clone technique, is developed. The method includes three stead: (1) Gametophyte clone culture. The spores and the gametophytes are cloned in flasks under favorable environments. (2) Sporeling cul ture. Male and female clones are crushed and spread onto a frame to allow the gametophytes to attach to the substrata. The frames are cultured in tanks, and the sporophytes reach 1 cm in length within one and a half months. (3) Outgrowing of the plant. The frames are put in the open sea when seawater temperature decreased to 20℃. After one month, the sporelings are large enough to be transplanted. It is concluded that the clone technique has the following advantages: (1)Large amount of clones can be produced in a short period of time. (2) Clone seeding method makes it free from the biological rhythm, one can seed the plant anytime all the year round. (3) It takes only one and a half months to complete the process of sporeling cultivation in the greenhouse. At present, this technique is used in the breeding of new strains of Laminaria.展开更多
An embryo classification system for Pinus tabuliformis Carr. was established by time-tracing sam- pling and observation of zygotic embryos. The zygotic embryos were divided into nine stages. Key elements of the zygoti...An embryo classification system for Pinus tabuliformis Carr. was established by time-tracing sam- pling and observation of zygotic embryos. The zygotic embryos were divided into nine stages. Key elements of the zygotic embryo and female gametophyte (FG) tissue of P. tabuliformis were analyzed, using inductively coupled plasma-emission spectroscopy. Several elements--includ- ing aluminum, iron, sodium, and copper--are found in both embryo and FG tissue. Boron, phosphorus, magnesium,zinc, and calcium are also required for zygotic embryo development and therefore accumulated. Manganese is selectively excluded from the embryo. The zygotic embryo development needs a low-sodium and high-potassium nutrition proportion. The results of elemental analysis from zygotic embryos and FGs can provide the mineral targets for optimizing the formulation of culture medium for somatic embryogenesis.展开更多
Florogenesis is one of the most complicated and interesting processes in the nature. This process involves developmental, physiological and molecular events leading to transformation from vegetative to reproductive ph...Florogenesis is one of the most complicated and interesting processes in the nature. This process involves developmental, physiological and molecular events leading to transformation from vegetative to reproductive phase for optimal seed production and the continuation of species. The basic knowledge about flowering processes, male and female sexual systems support basic and applied research and breeding programs. Most of the onion varieties from India are short day varieties, more diverse than other exotic germplasm and useful as a source of new alleles for supporting breeding programs. The present investigation was focused to study for the first time florogenesis process by scanning electron study for the first time florogenesis process by scanning electron microscopy (SEM) and development of female gametophytes by light microscopy in order to acquire basic knowledge useful for optimizing in vitro process to produce gynogenic haploid to support and speed breeding program in short-day onion Allium cepa L. cv. Krishnapuram (KP) or Bangalore Rose. This study revealed that shoot primordium differentiated into inflorescence meristem in the month of December, while seeds were planted in the field in the September. The individual florets are preceded by a variying number of floral initials. The female gametophyte developed from chalazal side megaspore. The embryo sac development is a bisporic Allium type showing short-lived antipodals. The histological study suggests that the use of big or preanthesis flower buds with embryo sac for production of gynogenic haploids to support breeding program in onion cv. Krishnapuram (KP). However further studies are needed for confirmation of this observation.展开更多
The microsporogenesis and male gametophyte development of Euphorbia pulcherrima were studied with paraffin section method. The results showed that the anther of Euphorbia pulcherrima had four chambers. The development...The microsporogenesis and male gametophyte development of Euphorbia pulcherrima were studied with paraffin section method. The results showed that the anther of Euphorbia pulcherrima had four chambers. The development of anther wall was dicotyledonous type; its wall consisted of epidermis, endothecium, middle layer and tapetum. The mature male gametophyte development experienced seven major stages as the followings: archesporial cells, aporgenous cells, microspore mother cells, tetrads of microspores (tetrahedral), uninucleate microspores, 2-uncleate pollens and 2-celled pollen stage. The anther wall varied with the pollen development: the epidermis of anther ruptures at the anther mature stage; the middle layer disappears at tetrad stage; the endothelium became fibrous layer at the anther mature stage; the tapetum (glandular) was the most development at the microspore mother cells stage and disappeared at anther mature stage. The abnormal anther development was observed simultaneously.展开更多
The aim of this study is to follow each development stage of inflorescence in order to understand the biological feature of flowering and the development of male gametophyte in Anthurium andreanum “Arizona' and ...The aim of this study is to follow each development stage of inflorescence in order to understand the biological feature of flowering and the development of male gametophyte in Anthurium andreanum “Arizona' and to try to find the optimum conditions for its pollination. The methods of dissection and paraffin section were adopted to examine the structural characteristics of anthurium’s tiny floret and the development of the microspore. All the florets of the anthurium arrange on the rhachis helically sub- tended by a colorful bract. Each tiny floret has one gynoecium, four tepals and four stamina. The bract and the florets show different colors during the whole blooming period. The ovary is bicarpellary and has two locules, each of which has one anatropous ovule. The placenta is of a central placentation type. The stylar canal cells not only can produce the secretory mucilage but also can release their own cytoplasm caused by their self-disintegration before the pistil reaches its maturity. The wall of the anther is composed of four layers: epidermis, endothecium, middle layer and tapetum. The tapetal cells and the middle layers’ cells degenerated completely dur- ing meiosis of microsporocytes. The pollen grains were 2-celled at the time of anther dehiscence. Early morning, when the inflores- cences stay at their fifth development stage, is the optimum opportunity for pistil to get pollen grains. The pollen-collection should be done at the end of the seventh stage.展开更多
In land plants, two distinct generations, gametophyte and sporophyte, alternate to complete the life cycle. Sporophytes undergo meiosis to produce spores, from which gametophytes develop. Gametophytes produce gametes,...In land plants, two distinct generations, gametophyte and sporophyte, alternate to complete the life cycle. Sporophytes undergo meiosis to produce spores, from which gametophytes develop. Gametophytes produce gametes, which participate in fertilization to produce the zygote, the first cell of the sporophyte generation. In addition to this sexual reproduction pathway, some fern species can undergo apospory or apogamy, processes that bypass meiosis or fertilization, respectively, to alternate between the two generations without changing the chromosome number. Apospory is inducible in the laboratory in various fern species simply by altering the sugar level in the media. In sporophytes induced to undergo apospory, sporophyte regeneration is also observed. The ratio of aposporous gametophytes to regenerated sporophytes varies, in a manner consistent with being dependent on sugar level. Whereas the sugar signaling pathway is yet to be elucidated in lower plants, in angiosperms it has been shown to play a regulatory role in controlling essential processes including flowering and embryo development, which give rise to the gametophyte and the next sporophyte generation, respectively. Here, we present evidence for the role of different sugar levels on the balance of apospory and regeneration in the fern Ceratopteris richardii. The demonstration of crosstalk between sugar signaling and the hormone ethylene signaling in angiosperms prompted us to test the effects of this hormone in combination with sugar on apospory vs. regeneration. These results provide insight into how a group of redifferentiating cells determines which generation to become and lay the groundwork for further analysis of this asexual pathway.展开更多
There were four microsporanges in the mature anther of B. rossica Fedtsch. et Flerov. The development of the anther wall belonged to dicotyledonous type. The tapetum cell was dichotypic. Simultaneous cytocinesis in th...There were four microsporanges in the mature anther of B. rossica Fedtsch. et Flerov. The development of the anther wall belonged to dicotyledonous type. The tapetum cell was dichotypic. Simultaneous cytocinesis in the microspore mother cells formed tetrad by reduction division and the array of microspore tetrads was different. There were tetrahedron type and bilateral symmetry type. The male gametophyte was 2-cell. The mature pollen was global and tricolporate. All those results were investigated under both light microscope (LM) and electron microscope (EM)展开更多
基金This paper is translated from its Chinese version in Scientia Agricultura Sinica.This research was partially supported by the Transcentury Training Program Foundation for the Talents by the Ministry of Education of China to Dr.Chen Jinfeng(30470120)by the National Natural Science Foundation of China(30671419)+2 种基金the National Hi-Tech R&D Program(2004AA241120)the Tang Foundation Cornell-China Scholar Programthe Pickle Seed Research Foundation of Pickle Packers International.The authors sincerely thank Dr.Zhai Huqu,the President of the Chinese Academy of Agricultural Sciences for his support in this research.
文摘An interspecific hybrid F1 of Cucumis hystrix Chakr. x Cucumis sativus L. (NC4406) was used to establish the developmental sequence and to characterize the male and female gametophytes at cytological level for further understanding of the phylogenic relationship and the mechanism of fertility or sterility in the interspecific hybrid F1 The development of male and female gametophytes was studied through meiotic analysis and paraffin section observation technique, respectively. Meanwhile, the fertility level was assessed through hybrid F1 backcrossing to cultivated cucumber 4406. Variable chromosome configurations were observed in the pollen mother cells (PMCs) of hybrid F1 at metaphase Ⅰ , e.g., univalents, bivalents, trivalents, quadravalents, etc. At anaphase Ⅰ and Ⅱ, chromosome lagging and bridges were frequently observed as well, which led to the formation of polyads and only a partial number of microspores could develop into fertile pollen grains (about 23.3%). Observations of the paraffin sections showed numerous degenerated and abnormal embryo sacs during the development of female gametophytes, and only 40% of the female gametophytes could develop into normal eight-nuclear megaspore. On an average, 22.8 and 6.3 seeds per fruit could be obtained from the reciprocal backcross. The interspecific hybrid F1 of C. hystrix x NC4406 was partially fertile; however, the meiotic behaviors of hybrid F1 showed a high level of intergenomic recombination between C. hystrix and C. sativus chromosomes, which indicated that it plays an important role for introgression of useful traits from C. hystrix into C. sativus.
文摘This study on the effects of ultrasonic treatment on female gametophytes of Laminariajaponica showed that:1. Ultrasonic treatment had shortening effect on filaments of female gametophytes. Within certainperiod of time, the average length of filamentous female gametophytes was shortened.2. Ultrasonic treatment had emptying effect on cells. The number of empty cells increased with timeof treatment. Ultrasonic treatment had harmful effect on cells.3. Ultrasonic treatment could break down cell walls. The combination of frequency of 20 kHz, out-put of 15 W, 40 s and 60 s of treatment was best for this purpose. After ultrasonic treatment, the regner-ation of female gametophytes into sporophytes was effected. Female gametophytes could not recover aftertoo long period of treatment.
文摘The objective of this study was to examine the eff ects of temperature and light intensity on growth of female gametophytes of Eisenia bicyclis and Ecklonia cava and responses of these female gametophytes to Fe addition and daylength. Female gametophytes of each species were cultured at four temperatures (10, 15, 20, and 25°C) and under a combination of four light intensities (10, 20, 40, and 80 μmol photons/(m^2 ·s)) with two temperatures (15 and 20°C for E i . bicyclis;20 and 25°C for E c . cava ) to clarify their optimal growth conditions. Growth and maturation of female gametophytes of these two species under a combination of five Fe-EDTA concentrations (0, 1, 2, 4, and 8 μmol/L) and three daylengths (10, 12, and 14 h) were also examined. The growth of E i . bicyclis gametophyte was maximal at approximately 15–20°C, 20 μmol photons/(m^2 ·s), Fe-EDTA concentration of 8 μmol/L and daylengths of 12–14 h. While E c . c ava gametophytes showed optimal growth at approximately 20–25°C, 20 μmol photons/(m^2 ·s), Fe- EDTA concentration of 8 μmol/L and daylength of 14 h. Maturation of gametophytes was enhanced at Fe-EDTA concentration of 4 μmol/L for E i . bicyclis and at 2 μmol/L for E c . c ava . In conclusion, optimal growth temperatures and Fe-EDTA concentrations for maturation of E i . bicyclis and E c . c ava gametophytes were diff erent. Higher optimal growth temperature for E c . c ava gametophytes may contribute to its wider geographical distribution compared to E i . bicyclis which has restricted habitats in Korea. This suggests that addition of Fe ion could be used to recover beds of these two species in barren grounds of Korea.
文摘Abstract: Inter-simple sequence repeat (ISSR) analysis was used to assess genetic diversity among 10 pairs of male and female Laminaria gametophytes. A total of 58 amplification loci was obtained from 10 selected ISSR primers, of which 34 revealed polymorphism among the gametophytes. Genetic distances were calculated with the Dice coefficient ranging from 0.006 to 0.223. A dendrogram based on the unweighted pair-group method arithmetic (UPGMA) average showed that most male and female gametophytes of the same species were clustered together and that 10 pairs of gametophytes were divided into four groups. This was generally consistent with the taxonomic categories. The main group consisted of six pairs of gametophytes, which were selected from Laminaria japonica Aresch. by intensive inbreeding through artificial hybridization. One specific marker was cloned, but was not converted successfully into a sequence characterized amplified region (SCAR) marker. Our results demonstrate the feasibility of applying ISSR markers to evaluate Laminaria germplasm diversities.
基金supported in part by the Foundation for Jiangsu Vocational College of Agriculture and Forestry of China(No.2017kj02)the Key Laboratory of Soil Environment and Pollution Remediation,Institute of Soil Science,Chinese Academy of Sciences(No.SEPR2017-10)+2 种基金the National Natural Science Foundation of China(No.21277070)Jiangsu Provincial Innovation Project of China(No.0211001802)the Program for Postgraduates Research and Innovation in Jiangsu Province,China(No.KYLX0052)
文摘Dear Editor, Environmental arsenic (As) contamination of both soil and water systems is a worldwide problem, and As can enter the human food chain through contaminated agricultural products and drinking water and contribute to the development of lung.
基金This research was supported by the National Key R&D Program of China(Grant No.2018YFD0901500)the National Natural Science Foundation of China(Grant No.41376136)the Double First-Class Discipline of Fisheries Science of China.
文摘Carbonic anhydrase(CA)was considered to be an important component of carbon concentrating mechanism(CCM)of algae.It was an inducible enzyme.Environmental factors,especially dissolved inorganic carbon and pH,were known to affect CA activity.Effects of inorganic carbon(CO_(2)and HCO_(3)^(-))and pH on CA activity of gametophytes of Saccharina japonica were evaluated in this study.Under high-CO_(2)condition(3%CO_(2)),the activity of external CA(C_(Aext))was significantly decreased(P<0.05)from 33.92 REA/g FW to 27.69 REA/g FW.In contrast,the internal CA(CA_(int))and total CA activities were elevated significantly(p<0.01)from 36.83 REA/g FW to 48.80 REA/g FW,and from 70.75 REA/g FW to 76.49 REA/g FW,respectively.Addition of an appropriate concentration of HCO_(3)^(-)to the medium,CA_(int)and total CA activities were promoted significantly,although the activity of C_(Aext)was inhibited significantly(P<0.05).In higher HCO_(3)^(-)concentration(up to 1680 mg/L),the activity of CA_(int)was promoted to 60.81REA/g FW,which was twice that of the control.Higher activities of CA_(int)and total CA were induced at low pH.At pH 6.0,the highest activities of CA_(int)(110.85 REA/g FW)and total CA(128.17 REA/g FW)were induced.However,at pH 9.0,the activities of CA_(int)and total CA were reduced to the lowest of 23.31REA/g FW and 42.19 REA/g FW,respectively.This is the first report about the successful detection of C_(Aext)activity of gametophytes of S.japonica.The results would provide data for the analysis of Ci acquisition and transport mechanism in S.japonica gametophytes.
基金Supported by the National High Technology Research and Development Program of China (Grant Nos. 20060110A4013 and 2006AA100311)National Natural Science Foundation of China (Grant No. 40506030)Innovative Key Project of the Chinese Academy of Sciences (Grant No. KZCX2-YW-209)
文摘The life cycle of seaweed Laminaria japonica involves a generation alternation between diploid sporophyte and haploid gametophte. The expression of foreign genes in sporophte has been proved. In this research, the recombinant expression in gametophyte was investigated by particle bombardment with the rt-PA gene encoding the recombinant human tissue-type plasminogen activator (Reteplase), which is a thrombolytic agent for acute myocardial infarction (AMI). Transgenic gametophytes were selected by their resistance to herbicide phosphiothricin (PPT), and proliferated in an established bubble column photo-bioreactor. According to the results from quantitative ELISA, Southern blotting, and fibrin agarose plate assay (FAPA) for bioactivity, it was showed that the rt-PA gene had been inte-grated into the genome of gametophytes of L. japonica, and the expression product showed the ex-pected bioactivity, implying the proper post-transcript modification in haploid gametophyte.
基金中国科学院资助项目,the Project of ScientificInnovation of the Chinese Academy of Sciences,国家科技攻关项目
文摘Effects of various concentrations of two heavy metals, namely Cd and Cu, on gametophytes of Laminariajaponica Aresch were determined by recording morphological changes of gametophytes, determining pH values and the heavy metal content of the culture solution, calculating the germination rate of sporophytes, and observing heavy metal (Cd) distribution using a fluorescence microscope. The results showed that heavy metals damaged the gametophytes, and were even lethal, and that the higher the concentration of heavy metal ions, the greater the injury to gametophytes. Gametophytes could not survive in culture solutions containing more than 100 mg/L Cd and 50 mg/L Cu and were only able to survive in culture solution containing a mixture of Cd and Cu up to a concentration of 10 mg/L, which indicates that gametophytes have a higher tolerance to Cd than Cu and that multiple heavy metal ions in solution markedly aggravate the damage to gametophytes compared with individual heavy metal ions. With increases in the concentration of the heavy metal, the burgeoning rate of sporophytes decreased acutely, and solutions containing multiple heavy metal ions caused even more marked harm to sporophytes than solutions containing a single heavy metal ion, because most sporophytes died in mixed solutions. The pH value of the culture medium dropped immediately at the beginning (the first day) of treatment, increased over the following days, and then decreased again. The pH of culture media containing multiple heavy metal ions showed greater variation than media containing a single heavy metal ion, with the extent of the decrease in pH of culture media containing multiple ions being greatest during the last period of the experiment. With increases in the concentration of heavy metals, the capacity of gametophytes to accumulate these ions increased. The blue fluorescent light emitted by the Cd-and Cd-binding protein complex existing in gametophytes in media containing different concentrations of Cd showed clearly the distribution of the ion in gametophytes and the results obtained were consistent with distribution determined using other methods. All results of the present study showed that gametophytes of L. japonica play a remarkable role as heavy metal decontaminators, especially with regard to Cd.
基金supported by the National Natural Science Foundation of China(No.132072962)the Agricultural Industrial Technology System in Shandong Province(No.SDAIT-26)+3 种基金the‘First Class Fishery Discipline’Programme[(2020)3]in Shandong Provincethe Special Talent Programme‘Yishi Yiyi’in Shandong Province,Chinathe National Key R&D Program of China(No.2018YFD0901500)the Shandong Province Agriculture Seed Project(No.2021LZ GC004)。
文摘Long non-coding RNAs(lncRNAs)regulate a variety of biological processes,including sexual reproduction and differentiation.Saccharina japonica,a commercially important brown alga in China,shows remarkable sexual dimorphism in haploid gametophytes.The sex of Saccharina japonica gametophytes is determined by UV sexual system.However,no results have been reported on the lncRNAs involved in the sex-related gene regulation of S.japonica.This study identified a number of lncRNAs and assessed their expression levels in male and female gametophytes.Among them,a total of 405 lncRNAs and 211 mRNAs showed differential expressions.Furthermore,the functions of target genes of differentially expressed lncRNAs(DELs)differed from those of differentially expressed genes(DEGs),suggesting that lncRNA may interact with other functional proteins,in addition to DEGs,to involve sex regulation in S.japonica.There were 32 and 90 potential cis-regulatory and trans-regulatory interactions between DELsDEGs,respectively.Five of these lncRNAs(LNC_002974,LNC_021059,LNC_038466,LNC_051584,and LNC_027400)interacted with putative male sex determination region(SDR)genes,suggesting that they act as regulators in gametophytes'sex regulation potentially.Findings from this study contribute to our understanding of the roles of lncRNAs in sex differentiation and lay the foundation for functional studies of candidate lncRNAs in the future.
基金Supported by the National Key R&D Program of China(No.2018YFD0901500)the Shanghai Sailing Program(No.17YF1407900),the National Natural Science Foundation of China(No.41576163)the Ocean Public Welfare Scientifi c Research Project,China(No.201205010)。
文摘Abstract Ulva linza is one of the species that causes green tides in the Yellow Sea,China.Due to the diffi culties in chromosomal preparation,the large numbers of chromosomes,and their relatively small sizes,there have been no reported studies on Ulva macroalgae chromosomes.The karyotypes and chromosomes in U.linza were observed after a series of treatments.The chromosomes were pretreated with 0.1%colchicine for 12 h and then mixed with enzymes.The samples were dropped from 30 cm height onto glass slides,which spread out the surface coat.These pretreatments were the optimal chromosomes preparation treatments.The prepared chromosomes were stained with 4',6-diamidino-2-phenylindole(DAPI),which is a fl uorescent probe sensitive and specifi c to DNA.The chromosome number in the haploid male and female gametophytes was n=9,and was 2 n=18 in the diploid sporophytes.The female gametophyte chromosomes were between 0.804 and 2.292μm in size,the male gametophyte chromosomes were between 0.917 and 2.916μm,and the sporophyte chromosomes were between 0.912 and 2.167μm.The relative sizes of the chromosomes were used to analyze the karyotypes of the female and male gametophyte chromosomes.The results provide a solid foundation for the basic technique that can be used to localize molecular markers of Ulva chromosomes.
文摘Unicellular gametophytes of Undaria pinnatifida (Harv.) Sur. were isolated in Qingdao, P. R. China in April 1993 and in Tokushima, southem Japan in March 1995. Diferent intraspecific crossings by using unicellular male and female gametophytes were successfully undertaken in Sept. of 1995 in Qingdao.Sporophytes were transplanted to two different locations for open an cultivation. One was at Zhanqiao (ZQ) Bay where the water current was slower than that of another location - Taipingjiao(TPJ). A total of218 adult sporophytes were harvested on January 12 and 18 from TPJ and ZQ repectively. For eacncombination, 10 sporophytes un cultivated. Analysis of the mprpholgical characteristics of adult spprophytes indicated that the longest length between two bases of the serration of pinnate bldes (W2) is a morphological characteristic that can be transferred from the parent plant to the next generations regardless of environmental variations. There was evidence that W2 was apparently determined by sex-linked factors, i.e, by male parental grametophyte.. Sporophytes from certain crossing combinations showed more vigorous growth than those from other crossing combinations. It is therrfore possible to select grametophyte strains which can be used as parental gametophytes for the seeding production of sporophytes with more vigorous growth within shorter cultivation period. The morphology of hybrids from a Qingdao strain and a Tokushima cultivated strain resembled that of both parental plants in frond feaures (wrinkled or smooth) and W2. Sporophyll formation also varied with strains. The fact that adult sporophytes resulting from the same crossing combinations have identical morphological characteristics under the same environmental conditions indicates the possibility of a new way to select strains which are expected to be ideal for commerical production by purposely selecting, propagating, and seeding unicellular gametophytes for sporeing production through freeliving techniques of gametophytes.
基金Under the auspices of National Key Research and Development Program of China(No.2016YFC0500300)National Natural Science Foundation of China(No.41675153)
文摘Suitable habitat is vital for the survival and restoration of a species.Understanding the suitable habitat range for lycophytes and ferns is prerequisite for effective species resource conservation and recovery efforts.In this study, we took Athyrium brevifrons as an example, predicted its suitable habitat using a Maxent model with 67 occurrence data and nine environmental variables in Northeast China.The area under the curve(AUC) value of independent test data, as well as the comparison with specimen county areal distribution of A.brevifrons exhibited excellent predictive performance.The type of environmental variables showed that precipitation contributed the most to the distribution prediction, followed by temperature and topography.Percentage contribution and permutation importance both indicated that precipitation of driest quarter(Bio17) was the key factor in determining the natural distribution of A.brevifrons, the reason could be proved by the fern gametophyte biology.The analysis of high habitat suitability areas also showed the habitat preference of A.brevifrons: comparatively more precipitation and less fluctuation in the driest quarter.Changbai Mountains, covering almost all the high and medium habitat suitability areas, provide the best ecological conditions for the survival of A.brevifrons, and should be considered as priority areas for protection and restoration of the wild resource.The potential habitat suitability distribution map could provide a reference for the sustainable development and utilisation of A.brevifrons resource, and Maxent modelling could be valuable for conservation management planning for lycophytes and ferns in Northeast China.
文摘After continuous breeding gametophyte of Laminaria, then breaking protonema, heterosis seedling is got by bilineal hybridization. The result shows that the weight-increasing rate of female and male gametophyte clone cells are 14.03% and 13.87%, after 16 d crossbreeding, the rate of ovulation is up to100%; the length of juvenile sporophyte after 40 d breeding is 2-3 cm. By farming on the sea, a hybrid combination is primarily screened.
基金Key Project, the Ninth Five-Year Plan of China! 96-008-01-02-06Project of Bio-Engineering Center of China! SSTC 96-C01-05-01
文摘In China, the total annual production of cultured Laminaria japonica reached half million tons in dry weight there few years. The routine sporeling culture technique conducted in the greenhouse took at least three and half months. In such a case, sometimes the sporelings died within a few days due to destructive diseases. In Order to overcome the mentioned problems, a new sporeling culture technique, the clone technique, is developed. The method includes three stead: (1) Gametophyte clone culture. The spores and the gametophytes are cloned in flasks under favorable environments. (2) Sporeling cul ture. Male and female clones are crushed and spread onto a frame to allow the gametophytes to attach to the substrata. The frames are cultured in tanks, and the sporophytes reach 1 cm in length within one and a half months. (3) Outgrowing of the plant. The frames are put in the open sea when seawater temperature decreased to 20℃. After one month, the sporelings are large enough to be transplanted. It is concluded that the clone technique has the following advantages: (1)Large amount of clones can be produced in a short period of time. (2) Clone seeding method makes it free from the biological rhythm, one can seed the plant anytime all the year round. (3) It takes only one and a half months to complete the process of sporeling cultivation in the greenhouse. At present, this technique is used in the breeding of new strains of Laminaria.
基金financially supported by an open fund of the Key Laboratory of Forest Genetics and BiotechnologyMinistry of Education and Jiangsu Province+3 种基金Nanjing Forestry University(FGB200901)the‘‘948’’project of China(2014-4-59)the Project of National Natural Science Foundation of China(No.31370658)‘‘the Mutual Fund of Beijing Government and Central Universities in Beijing(GJ2011-2)’’
文摘An embryo classification system for Pinus tabuliformis Carr. was established by time-tracing sam- pling and observation of zygotic embryos. The zygotic embryos were divided into nine stages. Key elements of the zygotic embryo and female gametophyte (FG) tissue of P. tabuliformis were analyzed, using inductively coupled plasma-emission spectroscopy. Several elements--includ- ing aluminum, iron, sodium, and copper--are found in both embryo and FG tissue. Boron, phosphorus, magnesium,zinc, and calcium are also required for zygotic embryo development and therefore accumulated. Manganese is selectively excluded from the embryo. The zygotic embryo development needs a low-sodium and high-potassium nutrition proportion. The results of elemental analysis from zygotic embryos and FGs can provide the mineral targets for optimizing the formulation of culture medium for somatic embryogenesis.
文摘Florogenesis is one of the most complicated and interesting processes in the nature. This process involves developmental, physiological and molecular events leading to transformation from vegetative to reproductive phase for optimal seed production and the continuation of species. The basic knowledge about flowering processes, male and female sexual systems support basic and applied research and breeding programs. Most of the onion varieties from India are short day varieties, more diverse than other exotic germplasm and useful as a source of new alleles for supporting breeding programs. The present investigation was focused to study for the first time florogenesis process by scanning electron study for the first time florogenesis process by scanning electron microscopy (SEM) and development of female gametophytes by light microscopy in order to acquire basic knowledge useful for optimizing in vitro process to produce gynogenic haploid to support and speed breeding program in short-day onion Allium cepa L. cv. Krishnapuram (KP) or Bangalore Rose. This study revealed that shoot primordium differentiated into inflorescence meristem in the month of December, while seeds were planted in the field in the September. The individual florets are preceded by a variying number of floral initials. The female gametophyte developed from chalazal side megaspore. The embryo sac development is a bisporic Allium type showing short-lived antipodals. The histological study suggests that the use of big or preanthesis flower buds with embryo sac for production of gynogenic haploids to support breeding program in onion cv. Krishnapuram (KP). However further studies are needed for confirmation of this observation.
文摘The microsporogenesis and male gametophyte development of Euphorbia pulcherrima were studied with paraffin section method. The results showed that the anther of Euphorbia pulcherrima had four chambers. The development of anther wall was dicotyledonous type; its wall consisted of epidermis, endothecium, middle layer and tapetum. The mature male gametophyte development experienced seven major stages as the followings: archesporial cells, aporgenous cells, microspore mother cells, tetrads of microspores (tetrahedral), uninucleate microspores, 2-uncleate pollens and 2-celled pollen stage. The anther wall varied with the pollen development: the epidermis of anther ruptures at the anther mature stage; the middle layer disappears at tetrad stage; the endothelium became fibrous layer at the anther mature stage; the tapetum (glandular) was the most development at the microspore mother cells stage and disappeared at anther mature stage. The abnormal anther development was observed simultaneously.
基金Supported by the Graduate Students’ Research Foundation of Beijing Forestry University
文摘The aim of this study is to follow each development stage of inflorescence in order to understand the biological feature of flowering and the development of male gametophyte in Anthurium andreanum “Arizona' and to try to find the optimum conditions for its pollination. The methods of dissection and paraffin section were adopted to examine the structural characteristics of anthurium’s tiny floret and the development of the microspore. All the florets of the anthurium arrange on the rhachis helically sub- tended by a colorful bract. Each tiny floret has one gynoecium, four tepals and four stamina. The bract and the florets show different colors during the whole blooming period. The ovary is bicarpellary and has two locules, each of which has one anatropous ovule. The placenta is of a central placentation type. The stylar canal cells not only can produce the secretory mucilage but also can release their own cytoplasm caused by their self-disintegration before the pistil reaches its maturity. The wall of the anther is composed of four layers: epidermis, endothecium, middle layer and tapetum. The tapetal cells and the middle layers’ cells degenerated completely dur- ing meiosis of microsporocytes. The pollen grains were 2-celled at the time of anther dehiscence. Early morning, when the inflores- cences stay at their fifth development stage, is the optimum opportunity for pistil to get pollen grains. The pollen-collection should be done at the end of the seventh stage.
文摘In land plants, two distinct generations, gametophyte and sporophyte, alternate to complete the life cycle. Sporophytes undergo meiosis to produce spores, from which gametophytes develop. Gametophytes produce gametes, which participate in fertilization to produce the zygote, the first cell of the sporophyte generation. In addition to this sexual reproduction pathway, some fern species can undergo apospory or apogamy, processes that bypass meiosis or fertilization, respectively, to alternate between the two generations without changing the chromosome number. Apospory is inducible in the laboratory in various fern species simply by altering the sugar level in the media. In sporophytes induced to undergo apospory, sporophyte regeneration is also observed. The ratio of aposporous gametophytes to regenerated sporophytes varies, in a manner consistent with being dependent on sugar level. Whereas the sugar signaling pathway is yet to be elucidated in lower plants, in angiosperms it has been shown to play a regulatory role in controlling essential processes including flowering and embryo development, which give rise to the gametophyte and the next sporophyte generation, respectively. Here, we present evidence for the role of different sugar levels on the balance of apospory and regeneration in the fern Ceratopteris richardii. The demonstration of crosstalk between sugar signaling and the hormone ethylene signaling in angiosperms prompted us to test the effects of this hormone in combination with sugar on apospory vs. regeneration. These results provide insight into how a group of redifferentiating cells determines which generation to become and lay the groundwork for further analysis of this asexual pathway.
文摘There were four microsporanges in the mature anther of B. rossica Fedtsch. et Flerov. The development of the anther wall belonged to dicotyledonous type. The tapetum cell was dichotypic. Simultaneous cytocinesis in the microspore mother cells formed tetrad by reduction division and the array of microspore tetrads was different. There were tetrahedron type and bilateral symmetry type. The male gametophyte was 2-cell. The mature pollen was global and tricolporate. All those results were investigated under both light microscope (LM) and electron microscope (EM)