• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Vascular bundle connection between seed stalk and seed coat of Caragana arborescens

    2018-03-27 12:10:20ZhihuiLuanDaoweiZhouDiankunShao
    Journal of Forestry Research 2018年1期

    Zhihui Luan·Daowei Zhou·Diankun Shao

    Introduction

    The seed stalk provides the connection between plant generationsand is considered as the ‘umbilical cord’orjoining point between the seed and ovary wall of a plant(Jaisankar et al.2014).The seed stalk develops from a small-headed handleoftheovule,anditistheonlypathwaythroughwhich the plant transmits photosynthates into the seed(Bouman and Schier 1979).The funiculus of the angiosperm ovule maybelongandthin,orshortandstout,oritmaybemissing completely.If missing,the ovule is sessile(Wang and Ren 2007).Generally,the ovule develops into a seed following plantfertilization,andthe funiculusdevelopstoaseed stalk;however,the funiculus fails to directly develop into a seed stalk in the ovules of some plants,such as Liliaceae plants(Bouman 1977;Tilton and Horner 1980;Matsui et al.1993;Umeda et al.1994),in which the third bead layer of the funiculus finally develops into an aril(Tilton and Horner 1980).In some Magnoliaceae plants,the appendage of the handle that protrudes from the funiculus forms a closed junction with the horseshoe-like outer integument(McNaughton and Robertson 1974),and finally,this junction develops into a goblet-shaped outer integument(Matsui et al.1993;Umeda et al.1994).

    The diversion of photosynthates into the seed,by the seed stalk,increases seed yield.The cross-sectional view of the seed stalk shows a junction between the inner integument and the seed stalk at the base of the handle.At that junction are two closely connected layers of sclerenchymatous cells that form a very large depression(Wang et al.2003).The function of this depression is to attach the seed and facilitate its growth.In particular,at the hilum,fencelike cells form a small opening,which is the only channel for the outer mesocarp cells to transport photosynthates to the seed(Wang et al.2003).For example,if the funiculus of soybeans have well-developed vessel systems,the transfer of photosynthates will be very ef ficient.Subsequently,seed production will also increase(Wang et al.2004).The funiculus vessel system is considered an important anatomical structure for enhancing or improving breeding for high light ef ficiency(Wang et al.2003,2004).

    Caragana arborescens,an erect shrub or small tree,commonly known as caragana or Siberian pea tree(Allen et al.1955),is used as an ornamental hedge in northeastern China(Zhang and Chen 1990)because of its tolerance to drought in cold,semiarid regions.In Inner Mongolia,millions of seedlings have been planted for medicinal purposes,such as treatment of cough and gynecological disease(Zhao 2006),and for field and green belt purposes(Milovidov 1925).C.arborescens has pod fruits that contain many seeds(Liu 1993).The caragana has a slightly bitter tasting ‘pea’,usually 3–4 in a pod,which is edible but should be cooked before eating.These ripen in July and if left,will fall from the shrub,and the seeds will grow to become a new plant next to the parent shrub.In some areas of the United States,this plant is considered an invasive species.Grasshoppers can defoliate this species in some years,but it recovers well from the attacks.However,there is no knowledge on the seed stalk of C.arborescens.

    In this study,scanning electron microscopy(SEM)was employed to investigate the morphology,transmission route of photosynthetic products of the seed stalk of C.arborescens,and evaluate the role of the seed stalk in seed maturation.Our finding would be of great practical signi ficance for the breeding of C.arborescens and would provide theoretical evidence to advance breeding of C.arborescens.

    Materials and methods

    Specimen collection and treatment

    Since 31 May 2008,30 fresh fruits were collected from the upper,middle and lower layers of the same Caragana plant after flowering at 9:00 h on the day of collection.Half of the fresh fruits were fixed in 2.5%glutaraldehyde(pH 6.7)at 4°C,and the other half was naturally dried.Each sample was numbered.

    Scanning electron microscopy

    The full seed of each fruit was cut with a knife along the junction between the base of the seed stalk and the endocarp layer.The fixed seeds were washed three times with 0.1 M PBS,dehydrated with a graded ethanol series,which was replaced by isoamyl acetate.Then,seeds were criticalpoint dried and sputter-coated with gold–palladium.Samples were then observed with a Hitachi S-3000N scanning electron microscope(Hitach;Tokyo,Japan)at an accelerating voltage of 15.0 kV.

    Results and discussion

    Morphology of the funiculus

    The funiculus of the C.arborescens seed appeared a hammer-like shape,approximately 1750 μm long and 375 μm wide.Parenchymatous cells were densely arranged in regular shapes on the funiculus surface,measuring(19.05 × 38.09)–(152.38 × 171.43)μm2.In cross section,the handle was full of parenchymatous cells,and the center contained a large number of vessel cells,which have a transport function(Fig.1).

    Morphology of seed stalk base

    Fig.1 Cross section of the funiculus of C.arborescens seed viewed with scanning electron microscopy(×1000,lower right graph scale:dotted scale bar 50 μm)

    During seed formation,the funiculus,which serves as the only bridge that connects the ovule with the external environment,has a particular role.At an early stage of seed development,the funiculus develops completely into a seed stalk.At the junction between the seed stalk and seed,there is a group of elongated cells forming a ring(Fig.2).A very large hollow is present in the center of the ring,which is composed of two layers of sclerenchymatous cells.This ring is important for sustaining the attachment during the development of seeds in the embryo sac,and a few vessels were found at the top of the ring.At a late stage of seed development,the boundary between the ring and the seed coat is very apparent.The ring is blunter than at the early stage and has a deeper,more pronounced hollow.During seed maturation,the volume of the seed stalk increased,and the boundary of the stalk with the seed coat cells became indistinct as the hollow disappeared.A small opening in the center leads to the inside of the seed.

    Like the morphological structure of soybean,a ring formed by a group of elongated cells was seen at the junction between the Caragana seed stalk and seed.The opening in the center of the ring is closed during early seed development and opens as the seed matures,in agreement with the observations of the transmission tissues in the soybean funiculus(Wang et al.2004).This change is associated with the transport of the large amount of photosynthates required for seed growth.With the growth of seeds,the ring enlarges,and its boundary with seed coat is apparent.However,the boundary is indistinct after seed maturation.This change in the boundary may be explained as follows:the seed stalk cells divide rapidly as the seeds grow,and they differentiate into cells for transporting nutrients;the seed stalk falls off after the seeds mature,and the seed coat cells divide and displace the original seed stalk cells.In addition,the number of vessels on the top of the ring gradually increases as the seeds enlarge,and the lumen diameter of the vessels also enlarges.These changes likely increase transport rates.

    Fig.2 Scanning electron micrograph of surface of the junction between seed stalk and seed of C.arborescens as arrows pointing(×500,lower right scale:dotted scale bar 100 μm)

    Transport route of photosynthates

    Early in seed development,two layers of sclerenchymatous cells were densely arranged at the growth site of the seed stalk.They formed two fence-like layers around the entire growth site.These layers appeared fence-like and had a long spindle shape(Fig.3),when the opening of these fence-like cells was closed in the seed stalk.Numerous vessels extended from the seed stalk to the interior part of the seed.Later in seed development,the seed coat cells formed a large opening at the junction between the seed stalk and seed coat,thus opening the route for transferring photosynthates.In addition,the vessels extended into the seed along both sides of the seed coat cells.

    Pathway for material transport

    During late seed development,two potential pathways were apparent for transporting materials from the seed stalk to the seed interior.The junction between seed stalk and seed is seen by the longitudinal section of the seed.One portion of vessels extended into the seed coat cells(Fig.3),while most of the vessels went directly into the embryo(Fig.4).The vessels were arranged in a spiral pattern outside the seed coat and associated with seed coat cells.The vessels were concentrated in a net-like manner inside the seed coat cells,presumably showing the pattern of transport.

    Fig.3 Scanning electron micrograph of vessel extending into the seed coat of C.arborescens as the arrow pointing and fence-like layers in the circle(×250,lower right scale:dotted scale bar 200 μm)

    Fig.4 Scanning electron micrograph of vessel extending into the embryo as arrows pointing(×400,lower right scale:dotted scale bar 100 μm)

    SEM observation of longitudinal sections of the seeds revealed two routes of transport.One route started from the seed stalk,extended through the seed coat,and reached the inside of the seed,while the other directly entered the embryo.Both pathways were associated with vessels.However,the screw thread was thickened on the vessels in the seed stalk,and densely packed vessels,characterized by thickening of the net thread,were observed inside the seed coat cells.The vessels with thickened screw threads facilitate the entrance of external substances into the seed,while the vessels with thickening of the net threads inside the seed coat cells facilitate the even distribution of external nutrients in the seed.Further studies are required to investigate the cells that constitute this route and their effects on photosynthate transport.Extensive studies on the ultrastructure of the cells in the seed stalk will help elucidate structure–function relationships.

    Vessel morphology

    Fig.5 Scanning electron micrograph of vessels cross seed coat into the embryo(×700,lower right scale:dotted scale bar 50 μm)

    Fig.6 Scanning electron micrograph showing detail of vessels anatomy inside the seed(×900,lower right graph scale:dotted scale bar 50 μm)

    Vessels were presents in the funiculus for transport.During seed maturation,a minor alteration was seen in the morphology of the vessels.At an early stage of seed development,densely packed vessels were found on the top of ring at the junction between the seed stalk and seed,with a lumen of small diameter.The vessels extended along the seed stalk into the interior part of the seed in a radial pattern,and there were a large number of granular photosynthetic assimilation products in the cells around the vessels,which demonstrated the function of vessels to transport photosynthetates.The vessels were densely packed at the seed coat.Secondary thickenings on the cell walls were mainly characterized by thickening of the net thread(Fig.5).At late stage of seed development,the vessels were overlapped.The secondary thickening of the cell wall was still characterized by thickening of the net thread;however,the arrangement was regular.This variation may be caused by the different functions of various vessels.In the seed stalk,the photosynthetic products of leaf and pod were various,and the vessels with thickening of the net thread may facilitate the transportation of the photosynthetic products.Reducing sugar are substances that transport photosynthetic products inside the seed,and the vessels with thickening of the screw thread would facilitate the rapid transportation.After the full maturation of the seed,there was large space in the middle of the vessels,which may enhance the ef ficiency of material transportation.

    Distribution and morphology of vessels inside the seed

    Extensive distribution of the vessels was found inside the seed.Starting from the seed stalk,the vessels extended at the lower part of the seed coat cells(Fig.6).

    Conclusions

    SEM observation of the seed stalk of C.arborescens after flowering reveals that the mature seed stalk is mainly consisted of vessels, sclerenchymatous cells and parenchymatous cells.The gathering elongated cells form a ring at the junction between seed stalk and seed,and there is a large hollow produced by two layers of sclerenchymatous cells in the interior seed,which functions to sustain seed growth.The opening is closed in the center of the ring at early stage of seed development,and the opening enlarges with the maturation of the seed.There are two routes of material transportation which start from the seed stalk:one from seed coat to embryo,and another directly entering the embryo.Vessels,which are abundant in the seed stalk,are the pathway for absorption of nutrients by the seeds.The vessels are densely packed in the seed stalk,and the secondary thickening of the cell wall of the vessels is characterized by net thread thickening,while the secondary thickening of the cell wall of the vessels within the seed is characterized by screw thread thickening.The morphological characteristics of vessel are adaptive to its functions.

    AcknowledgementsWe thank Professor Jimin Zhao of Changchun University and Wei Zheng of JiLin Provincial Institute of Education for their comments on the manuscript.

    Allen EK,Gregory KF,Allen ON(1955)Morphological development of nodules on Caragana arborescens Lam.Can J Bot 33(2):139–148

    Bouman F(1977)Integumentary studies in the Polycarpicae IV.Liriodendron tulipifera L.Acta Bot Neerl 26(3):213–223

    Bouman F,Schier S(1979)Ovule ontogeny and seed coat development in Gentiana with a discussion on the evolutionary origin of the single integument.Acta Bot Neerl 28(6):467–478

    Jaisankar I,Sankaran M,Singh DR,Damodaran V(2014)Genetic variability and divergence studies in pod and seed traits of Pongamia pinnata(L.)Pierre.,accessions in Bay Islands.J For Res 25(2):351–358

    Liu YX(1993)Caragana arborescens.Flora of China.Beijing:Science Press 42(1):13–67

    Matsui M,Imaichi R,Kato M(1993)Ovular development and morphology of some magnoliaceae species.J Plant Res 106(4):297–304

    McNaughton JE,Robertson BL (1974)Megasporogenesis and megagametogenesis in Aloe africana Mill.South Afr J Bot 40(1):75–79

    Milovidov P(1925)Bactéries des tubercules radicaux de certaines légumineuses.Publs Fac Sci Univ Charles 49(1):3–40

    Tilton VR,Horner HT Jr(1980)Stigma,style,and obturator of Ornithogalum caudatum(Liliaceae).Am J Bot 67(7):1113–1131

    Umeda A,Imaichi R,Kato M(1994)Ovular development and morphology of the outer integument of Magnolia grandi flora(Magnoliaceae).Am J Bot 81(3):361–367

    Wang ZF,Ren Y(2007)Advances in the study of the angiosperm ovule.Chin Bull Bot 24(1):49–59(in Chinese)

    Wang XD,Cang J,Cui L,Gui MZ(2003)Scanning electron microscopic observation on seed stalk of soybean.J Chin Electr Microsc Soc 22(6):500(in Chinese)

    Wang XD,Cang J,Zhang P,Cui L(2004)Scanning electron microscopic observation on seed stalk transmission tissue of soybean.J Chin Electr Microsc Soc 23(4):354(in Chinese)

    Zhang ER,Chen F(1990)The rapid propagation on tissue culture of Caragana arborgce.J Northeast Agric Coll 23(1):94–97(in Chinese)

    Zhao YZ(2006)The distribution pattern and ecological adaptation of Caragana sibirica Fabr.Bull Bot Res 26(1):402–404(in Chinese)

    亚洲国产高清在线一区二区三| 丰满人妻一区二区三区视频av | 日本 av在线| 国产成人福利小说| 亚洲国产欧美一区二区综合| 色av中文字幕| 免费一级毛片在线播放高清视频| 午夜视频精品福利| 五月玫瑰六月丁香| 最近在线观看免费完整版| 在线播放国产精品三级| 亚洲专区字幕在线| 999久久久国产精品视频| 欧美黑人欧美精品刺激| 精品欧美国产一区二区三| 日韩欧美国产在线观看| 夜夜看夜夜爽夜夜摸| 国产精品av视频在线免费观看| 香蕉丝袜av| 非洲黑人性xxxx精品又粗又长| 精品国内亚洲2022精品成人| 两个人的视频大全免费| 男女床上黄色一级片免费看| 午夜精品久久久久久毛片777| 国产成人啪精品午夜网站| 两性午夜刺激爽爽歪歪视频在线观看| 欧美日本亚洲视频在线播放| 露出奶头的视频| 精品熟女少妇八av免费久了| 成人精品一区二区免费| 成人国产一区最新在线观看| 久久久精品欧美日韩精品| 国产麻豆成人av免费视频| 91老司机精品| 精品国产超薄肉色丝袜足j| 丰满的人妻完整版| 日韩高清综合在线| 国产久久久一区二区三区| 熟妇人妻久久中文字幕3abv| 男人舔奶头视频| 成人特级av手机在线观看| 男人和女人高潮做爰伦理| 久久久久精品国产欧美久久久| 国产伦在线观看视频一区| 色哟哟哟哟哟哟| 亚洲国产精品999在线| 国产人伦9x9x在线观看| xxx96com| 国产免费男女视频| 国产一级毛片七仙女欲春2| 国产真人三级小视频在线观看| 免费av毛片视频| 2021天堂中文幕一二区在线观| 99在线人妻在线中文字幕| 免费观看的影片在线观看| 亚洲美女搞黄在线观看| 久久久久久久久久久免费av| 国产午夜福利久久久久久| 国产 一区精品| 亚洲内射少妇av| 嫩草影院新地址| 桃色一区二区三区在线观看| 久久精品熟女亚洲av麻豆精品 | 日韩高清综合在线| 午夜精品在线福利| 午夜福利在线观看吧| 免费观看的影片在线观看| 秋霞在线观看毛片| 成人亚洲精品av一区二区| 真实男女啪啪啪动态图| 真实男女啪啪啪动态图| 尾随美女入室| 色5月婷婷丁香| 国产成人午夜福利电影在线观看| 天堂av国产一区二区熟女人妻| 久久精品国产亚洲av天美| 国产精品美女特级片免费视频播放器| 久久6这里有精品| 国产av不卡久久| 日本色播在线视频| 国产精品综合久久久久久久免费| 色综合色国产| 免费av观看视频| 国产亚洲精品av在线| 国产精品一区二区三区四区免费观看| 精品国产一区二区三区久久久樱花 | 99久久精品热视频| 长腿黑丝高跟| 亚洲怡红院男人天堂| 亚洲av福利一区| 黄片wwwwww| 亚洲精品乱久久久久久| 亚洲真实伦在线观看| 国产成人精品久久久久久| 中文亚洲av片在线观看爽| 特级一级黄色大片| 联通29元200g的流量卡| 精品人妻一区二区三区麻豆| 成年免费大片在线观看| 亚洲国产色片| 国产精品久久视频播放| 日本免费a在线| 久久久久久大精品| 亚洲一级一片aⅴ在线观看| eeuss影院久久| 亚洲精品久久久久久婷婷小说 | 男女下面进入的视频免费午夜| 久久久久久九九精品二区国产| 全区人妻精品视频| 波野结衣二区三区在线| 欧美日韩国产亚洲二区| 欧美变态另类bdsm刘玥| 亚洲国产高清在线一区二区三| 婷婷色综合大香蕉| www日本黄色视频网| 久久久久久九九精品二区国产| av.在线天堂| 大香蕉久久网| 尾随美女入室| 小蜜桃在线观看免费完整版高清| 亚洲在线自拍视频| 国产精品久久电影中文字幕| 国产69精品久久久久777片| 国产精品美女特级片免费视频播放器| 日本黄色片子视频| 国产乱人偷精品视频| 国产高清三级在线| 国产激情偷乱视频一区二区| 国产精品人妻久久久久久| 看黄色毛片网站| www.av在线官网国产| 中文亚洲av片在线观看爽| 日产精品乱码卡一卡2卡三| 色吧在线观看| 最近最新中文字幕免费大全7| a级毛片免费高清观看在线播放| 亚洲精品影视一区二区三区av| 一级毛片我不卡| 美女cb高潮喷水在线观看| 成人午夜高清在线视频| 精品午夜福利在线看| 一级二级三级毛片免费看| 久久6这里有精品| 国产精品一区www在线观看| 99久久精品国产国产毛片| 嫩草影院入口| 一级毛片我不卡| 国产成人a∨麻豆精品| 岛国在线免费视频观看| 亚洲精品影视一区二区三区av| 国产精品久久久久久精品电影| 久久国产乱子免费精品| av国产免费在线观看| 日日撸夜夜添| a级毛片免费高清观看在线播放| 亚洲欧美日韩卡通动漫| 亚洲国产最新在线播放| 精品一区二区三区视频在线| 欧美成人午夜免费资源| 亚洲最大成人中文| 精华霜和精华液先用哪个| 淫秽高清视频在线观看| 国产精品三级大全| 久久韩国三级中文字幕| 久久久久性生活片| 天堂网av新在线| 黄色配什么色好看| 永久网站在线| 天天躁夜夜躁狠狠久久av| 少妇人妻一区二区三区视频| 国产精品人妻久久久影院| 亚洲av熟女| 丰满少妇做爰视频| 亚洲va在线va天堂va国产| 亚洲最大成人手机在线| 中文字幕制服av| 久久亚洲国产成人精品v| 亚洲第一区二区三区不卡| 国产真实伦视频高清在线观看| 人人妻人人澡欧美一区二区| 天堂中文最新版在线下载 | 人妻夜夜爽99麻豆av| 亚洲成人中文字幕在线播放| 久久精品影院6| 五月伊人婷婷丁香| 男女下面进入的视频免费午夜| 亚洲欧洲国产日韩| 久久久久久久久大av| 爱豆传媒免费全集在线观看| 亚洲av免费在线观看| 色哟哟·www| 超碰av人人做人人爽久久| 岛国在线免费视频观看| 精品一区二区三区视频在线| a级毛色黄片| 99热这里只有是精品50| 伦理电影大哥的女人| 伦理电影大哥的女人| 在线a可以看的网站| 日本-黄色视频高清免费观看| av在线蜜桃| 天天躁夜夜躁狠狠久久av| 久久久午夜欧美精品| 日本色播在线视频| 搡女人真爽免费视频火全软件| av免费在线看不卡| 亚洲国产欧美在线一区| 日本猛色少妇xxxxx猛交久久| 中文字幕熟女人妻在线| 午夜亚洲福利在线播放| 好男人视频免费观看在线| 午夜免费激情av| 久久精品国产99精品国产亚洲性色| 精品久久国产蜜桃| 国产精品伦人一区二区| av黄色大香蕉| 国产免费男女视频| 亚洲激情五月婷婷啪啪| 床上黄色一级片| 成人av在线播放网站| 天堂影院成人在线观看| 日韩在线高清观看一区二区三区| 精品熟女少妇av免费看| 自拍偷自拍亚洲精品老妇| 亚洲精品自拍成人| 99久久中文字幕三级久久日本| 国产精品日韩av在线免费观看| 一区二区三区乱码不卡18| 亚洲国产成人一精品久久久| 国产免费男女视频| 亚洲精品自拍成人| 日韩一本色道免费dvd| 国产一区二区三区av在线| 日日撸夜夜添| 狂野欧美激情性xxxx在线观看| 午夜福利在线观看吧| 一区二区三区四区激情视频| 毛片一级片免费看久久久久| 免费看av在线观看网站| 婷婷色av中文字幕| 欧美97在线视频| 国产午夜精品一二区理论片| 亚洲性久久影院| 日本黄色视频三级网站网址| 色吧在线观看| 免费大片18禁| 午夜精品在线福利| 最近的中文字幕免费完整| 亚洲av成人精品一区久久| 国产av码专区亚洲av| 亚洲av福利一区| 简卡轻食公司| 又黄又爽又刺激的免费视频.| 亚洲成色77777| 26uuu在线亚洲综合色| 菩萨蛮人人尽说江南好唐韦庄 | 日本wwww免费看| 两个人视频免费观看高清| 久久久久网色| 亚洲在线自拍视频| 小说图片视频综合网站| 免费观看a级毛片全部| 色综合亚洲欧美另类图片| 日韩强制内射视频| 亚洲欧美日韩高清专用| 欧美成人精品欧美一级黄| 青春草视频在线免费观看| 国产伦一二天堂av在线观看| 亚洲第一区二区三区不卡| 成人三级黄色视频| 国产成年人精品一区二区| 校园人妻丝袜中文字幕| 在线免费十八禁| 国产精品麻豆人妻色哟哟久久 | 97超碰精品成人国产| 在线天堂最新版资源| 黄片无遮挡物在线观看| 美女黄网站色视频| 99九九线精品视频在线观看视频| 最后的刺客免费高清国语| 国产乱来视频区| 乱码一卡2卡4卡精品| 亚洲性久久影院| 午夜福利在线观看免费完整高清在| 国产一区二区在线观看日韩| 综合色av麻豆| 国产淫片久久久久久久久| 免费观看精品视频网站| ponron亚洲| 一级毛片电影观看 | 国产日韩欧美在线精品| 久久精品人妻少妇| or卡值多少钱| a级毛色黄片| 久久久久久久久中文| 国产极品天堂在线| 国产精品女同一区二区软件| 国产精品一二三区在线看| 99热精品在线国产| 一级黄色大片毛片| 国产精品国产三级国产av玫瑰| 亚洲欧美清纯卡通| 一级爰片在线观看| 国产免费福利视频在线观看| 亚洲熟妇中文字幕五十中出| 国产淫片久久久久久久久| 久久久久久久国产电影| 91狼人影院| 国内精品美女久久久久久| 搡女人真爽免费视频火全软件| 一个人免费在线观看电影| 国产精品一二三区在线看| 少妇高潮的动态图| 九九久久精品国产亚洲av麻豆| 亚洲aⅴ乱码一区二区在线播放| 亚洲精品一区蜜桃| 九草在线视频观看| 国产高潮美女av| 国产精品三级大全| 亚洲欧美清纯卡通| 级片在线观看| 成年版毛片免费区| 成人三级黄色视频| 我要看日韩黄色一级片| 亚洲av免费高清在线观看| 一级爰片在线观看| 日本-黄色视频高清免费观看| 免费电影在线观看免费观看| 一区二区三区乱码不卡18| 久久人妻av系列| 国产午夜福利久久久久久| 一边亲一边摸免费视频| 久久国内精品自在自线图片| 亚洲精品一区蜜桃| 色综合色国产| av又黄又爽大尺度在线免费看 | 亚洲四区av| 高清在线视频一区二区三区 | 久久精品久久久久久噜噜老黄 | 网址你懂的国产日韩在线| 亚洲av男天堂| 熟女人妻精品中文字幕| 国产欧美日韩精品一区二区| av天堂中文字幕网| 深夜a级毛片| 精品久久国产蜜桃| 性色avwww在线观看| 午夜久久久久精精品| 永久免费av网站大全| 乱人视频在线观看| 欧美另类亚洲清纯唯美| 精品国产一区二区三区久久久樱花 | 人人妻人人澡欧美一区二区| 国产av在哪里看| 国产精品一及| 久久综合国产亚洲精品| 91久久精品国产一区二区成人| 一级av片app| 亚洲国产精品sss在线观看| 淫秽高清视频在线观看| av女优亚洲男人天堂| 一级毛片aaaaaa免费看小| 成人毛片a级毛片在线播放| 国产高清视频在线观看网站| 男人的好看免费观看在线视频| 久久精品国产鲁丝片午夜精品| 人妻制服诱惑在线中文字幕| 精品人妻视频免费看| av在线天堂中文字幕| 国产乱来视频区| 97超碰精品成人国产| 日韩av在线免费看完整版不卡| 国产精品三级大全| 精品人妻熟女av久视频| 久久久精品大字幕| 身体一侧抽搐| 又粗又硬又长又爽又黄的视频| 免费观看的影片在线观看| 国产亚洲av片在线观看秒播厂 | 久久久久网色| 国产综合懂色| 国产精品久久久久久久电影| 99久久中文字幕三级久久日本| 丰满少妇做爰视频| 尤物成人国产欧美一区二区三区| 人人妻人人澡人人爽人人夜夜 | 熟妇人妻久久中文字幕3abv| 91aial.com中文字幕在线观看| 美女xxoo啪啪120秒动态图| 国产精品一二三区在线看| 色5月婷婷丁香| 国产午夜精品久久久久久一区二区三区| 我要看日韩黄色一级片| 青春草国产在线视频| 97超碰精品成人国产| 亚洲乱码一区二区免费版| 免费观看性生交大片5| 久久久久久久国产电影| 波野结衣二区三区在线| 国产私拍福利视频在线观看| 国产精品美女特级片免费视频播放器| 国产精品不卡视频一区二区| 少妇丰满av| 国产精品美女特级片免费视频播放器| 国产精品99久久久久久久久| 亚洲伊人久久精品综合 | 国产精品麻豆人妻色哟哟久久 | 日本黄色视频三级网站网址| 99久久中文字幕三级久久日本| 亚洲国产精品成人久久小说| 人人妻人人看人人澡| 久久精品久久久久久噜噜老黄 | .国产精品久久| 国产精品日韩av在线免费观看| 特大巨黑吊av在线直播| 国产av码专区亚洲av| 久久久久久国产a免费观看| 狂野欧美白嫩少妇大欣赏| 精品久久久久久久人妻蜜臀av| 久久99蜜桃精品久久| 97热精品久久久久久| 欧美97在线视频| 亚洲国产精品sss在线观看| 国语对白做爰xxxⅹ性视频网站| 亚洲无线观看免费| 丰满人妻一区二区三区视频av| 国产黄色视频一区二区在线观看 | 久久婷婷人人爽人人干人人爱| 日韩欧美精品免费久久| 亚洲三级黄色毛片| 国产乱人视频| 成人午夜高清在线视频| 久久久精品大字幕| 国产极品天堂在线| 亚洲精品国产av成人精品| 国产伦一二天堂av在线观看| 日韩制服骚丝袜av| 亚洲av免费高清在线观看| 可以在线观看毛片的网站| 国产精品福利在线免费观看| 在线免费十八禁| 国产老妇女一区| 国产精品爽爽va在线观看网站| 国产av一区在线观看免费| 国产三级在线视频| 男人的好看免费观看在线视频| 可以在线观看毛片的网站| 亚洲精品日韩av片在线观看| 毛片女人毛片| 亚洲国产日韩欧美精品在线观看| 国产伦精品一区二区三区视频9| 97热精品久久久久久| 午夜精品国产一区二区电影 | 亚洲精品,欧美精品| 亚洲欧美日韩卡通动漫| 国产色爽女视频免费观看| 婷婷色麻豆天堂久久 | kizo精华| 黄片wwwwww| 久久久久网色| 不卡视频在线观看欧美| 免费不卡的大黄色大毛片视频在线观看 | www.av在线官网国产| av在线天堂中文字幕| 亚洲av成人精品一区久久| 两个人的视频大全免费| 免费av毛片视频| 三级毛片av免费| 夜夜爽夜夜爽视频| 亚洲国产高清在线一区二区三| 欧美一区二区国产精品久久精品| 97热精品久久久久久| 国产淫语在线视频| 精品人妻视频免费看| 亚洲精品国产av成人精品| 久久久欧美国产精品| 久久久久精品久久久久真实原创| 在现免费观看毛片| 麻豆成人av视频| 在线免费观看的www视频| 久久精品国产亚洲网站| 一个人看的www免费观看视频| 少妇的逼好多水| 国产精品久久久久久久久免| av天堂中文字幕网| 91久久精品国产一区二区三区| 九九爱精品视频在线观看| 欧美精品一区二区大全| 免费看美女性在线毛片视频| 国产大屁股一区二区在线视频| 日韩精品青青久久久久久| 91精品伊人久久大香线蕉| 99久久精品一区二区三区| 在线观看一区二区三区| 成人av在线播放网站| 国产精品国产高清国产av| 变态另类丝袜制服| 欧美另类亚洲清纯唯美| 国产爱豆传媒在线观看| 国产成人a∨麻豆精品| 看黄色毛片网站| 国产成人免费观看mmmm| 建设人人有责人人尽责人人享有的 | 日韩强制内射视频| 国产色爽女视频免费观看| 欧美日本亚洲视频在线播放| 日本一二三区视频观看| 国产成人freesex在线| 中文字幕熟女人妻在线| 亚洲av中文字字幕乱码综合| 变态另类丝袜制服| 久久久久久久亚洲中文字幕| 九九久久精品国产亚洲av麻豆| 中文字幕亚洲精品专区| 村上凉子中文字幕在线| 美女高潮的动态| 人人妻人人澡欧美一区二区| 中文字幕精品亚洲无线码一区| 亚洲中文字幕一区二区三区有码在线看| 能在线免费看毛片的网站| 白带黄色成豆腐渣| 一个人免费在线观看电影| 18+在线观看网站| 国产一区二区亚洲精品在线观看| 国产色爽女视频免费观看| 热99在线观看视频| 三级毛片av免费| 中文天堂在线官网| 午夜福利视频1000在线观看| 欧美区成人在线视频| 亚洲婷婷狠狠爱综合网| 久久久久久久久久久免费av| 国产黄色小视频在线观看| 亚洲性久久影院| 免费大片18禁| 国产伦在线观看视频一区| 中国国产av一级| 午夜视频国产福利| 日韩三级伦理在线观看| 99久久人妻综合| 亚洲成人精品中文字幕电影| av女优亚洲男人天堂| 精品国产一区二区三区久久久樱花 | 九草在线视频观看| 国产黄色小视频在线观看| 亚洲无线观看免费| 激情 狠狠 欧美| 亚洲精华国产精华液的使用体验| 国国产精品蜜臀av免费| 欧美一级a爱片免费观看看| 草草在线视频免费看| 欧美另类亚洲清纯唯美| 亚洲欧美日韩无卡精品| 久久久久性生活片| 又粗又爽又猛毛片免费看| 精品一区二区三区视频在线| 精品国产露脸久久av麻豆 | 亚洲欧美精品专区久久| 简卡轻食公司| 久久精品91蜜桃| 亚洲精品国产av成人精品| 精品不卡国产一区二区三区| 亚洲精品影视一区二区三区av| 成年版毛片免费区| 精品免费久久久久久久清纯| 亚洲性久久影院| 国产精品精品国产色婷婷| 国产又色又爽无遮挡免| or卡值多少钱| 亚洲国产日韩欧美精品在线观看| 免费大片18禁| 九草在线视频观看| 欧美激情在线99| 国产精品国产高清国产av| 综合色丁香网| av在线亚洲专区| 亚洲av电影在线观看一区二区三区 | 日本免费在线观看一区| 亚洲欧美清纯卡通| 午夜福利在线观看免费完整高清在| 男人的好看免费观看在线视频| 精品国产露脸久久av麻豆 | 五月伊人婷婷丁香| 亚洲一区高清亚洲精品| 中文欧美无线码| 51国产日韩欧美| 中文字幕av成人在线电影| 欧美xxxx性猛交bbbb| 久久久午夜欧美精品| 亚洲一区高清亚洲精品| av免费观看日本| 中文字幕免费在线视频6| 国产伦精品一区二区三区视频9| 国产在线一区二区三区精 | 国产一区二区在线av高清观看| 国产色婷婷99| 精品久久久久久久久av| 秋霞伦理黄片| 成人特级av手机在线观看| 国产在线男女| 国产精品爽爽va在线观看网站| 看黄色毛片网站| 激情 狠狠 欧美| 色5月婷婷丁香| 亚洲av一区综合| 一个人看视频在线观看www免费| 免费观看人在逋| 亚洲最大成人中文| 色播亚洲综合网| 成人亚洲欧美一区二区av| 久久久久九九精品影院| 日本-黄色视频高清免费观看| 精品欧美国产一区二区三| 91久久精品电影网| 午夜激情欧美在线|