HOI NGH! KHOA HOC T O A N QUOC Vg SINH THAI VA TAI NGUYgN SINH VAT LAN THU BA
MOT SO DAC DIEM HINH THAI DE NHAN BIET CAC CHI HO GAI (URTICACEAE) NGOAI THIEN NHIEN 6 VIET NAM
DUO^G THIHOAN Vien Sinh thdi vd Tdi nguyen sinh vgt Hg Gai (Urticaceae Juss.) cd khoing 45 chi, horn 1.000 loii phan bd chu ylu d vimg nhift ddi vi can nhiet ddi, 6 Vift Nam, cd 23 chi vdi gin 100 Ioai, Tuy sd lugng chi va Ioai khdng Idn so vdi mdt sd hg thuc vat khac nhung Urticaceae li hg rat da dang va khi phirc tap vl mat phan Ioai, De giup cho phin Ioai hg Gai mgt'cich chinh xic vi thuan Igi, can thiet phii xic dinh nhtnig die diem hmh thai co ban ciia hg va tieu chuan chii yeu ciia cic taxon trong hg (tdng, chi), Bai bao nay gidi thifu mdt sd die diem hinh thai quan frgng de nhan biet cic chi hg Gai ngoai thien nhien,
L PHI/ONG PHAP NGHIEN ClTU
1. Doi tugng nghien ciru: Hg Urticaceae d Vift Nam (bao gom cac tieu bin khd dugc luu giir tai cac phdng tieu bin trong vi ngoii nudc vi cic loii sdng trong ty nhien dugc thu thip qua cic cudc dieu tra thye dia),
2. Phuong phap nghien ciru: Diing phuang phip so sinh hinh thii, la phuang phip nghien cim tmyen thdng, tuy don giin so vdi nhieu phuang phap khic, nhung thich hgp vdi dieu kifn d nudc ta, lai de dang frong nghien ciru do frang thiet bj khdng phurc tgp, de sir dung, va ve mit khoa hgc van cho nhimg ket qua dang tin cay. Phuang phap nay dya vio die diem hinh thai cua co quan sinh dudng vi co quan sinh sin de nghien ciru, frong dd chii yeu dya vio co quan sinh sin, do it bien ddi vi it phu thudc vio dieu kifn mdi tmdng ben ngoai, Chinh bang phucmg phip niy, nhieu tic gii da xay dyng thanh cdng cic hf thdng phan Ioai ciing nhu cic hf thdng phat sinh ciia thye vat,
U. KET QUA NGHIEN CUtf
1. Dang song: Cac Ioai thugc hg Gai (Urticaceae) d Vift Nam thudng gip la nhirng ciy than cd (Urtica, Elatostema, Pilea, Lecanlhus...), cd mgt nim (Girardinia, Lecanthus,...) hay nhieu nam (Nanocnide, Chamabainia,...), da sd li cd dirng (Laportea, Lecanlhus, Maoutia,...), it khi li cd bd (Procris, Chamabainia, Elatostema), cay byi thap (Boehmeria, Laportea, Oreocnide,...), ddi khi la nhumg cay gd nhd hay nhd (Dendrocnide, Debregeasia). Cay cd the phan cinh hoic khdng, than va cinh non thudng cd Idng, it khi nhin, die bift mgt so chi cd Idng ngira (Dendrocnide, Laportea, Girardinia, Nanocnide, Urtica). Vd ciy thudng cd sgi, ddi khi li cay mgng nudc (Elatostema). Te bao bieu bi phan ldn cd nang thgch (cystolith) ndi len cd dang chim (punctiform) hoic dang vgch (line).
2. L i : La dan, thudng mgc cich, mdt so chi mgc ddi, li cimg cip bing nhau (Urtica, Chamabainia, Boehmeria, Pouzolzia) hay la cimg cip khic nhau, 1 to 1 nhd (Pilea, Procris, Lecanlhus, Meniscogyne), phien Ii mdng hoic rap, kich thudc ldn nhd khic nhau, cd nhilu hinh dgng nhu hinh tim (Dendrocnide, Debregeasia, Laportea), hinh frdn (Pilea, Debregeasia, Boehmeria), hinh tning (Laportea, Pilea), hinh biu dye (Elatostema, Oreocnide, Debregeasia), hinh miii giio (Boehmeria, Pilea), hinh thudn dii (Pellionia, Pouzolzia). Li thudng nguyen, it khi cd thuy (Girardinia, Laportea, Urtica), goc li thucmg thudn, ddi khi trdn vi die trung Ii gde la Ifch (Elatostema, Lecanthus, Petelotiella), chdp li thudng nhgn hoic keo dai thanh mui, ddi khi frdn, mep la cd ring cua diu hay khdng diu, thua hay mau, to hay nhd, ddi khi la mep nguyen (Parietaria. Oreocnide); gin Ii thudng Ii gan hinh ldng chim vdi 3 hoic 5 gan xuit phat tir goc (Pilea, Boehmeria. Elatostema...), hay gan hinh chan vjt (Urtica, Girardinia), la nhin
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HOI NGHI KHOA HQC T O A N Q U O C Vg SINH THAI V A TAI NGUYgN SINH VAT LAN THU- BA
hay chi cd ldng d mgt mit hoic cd long d c i 2 mit, cudng la dii, ngin hoic khdng cudng. L i thudng mau xanh, mgt sd it miu tim (Laportea) (hinh 1).
J i I
!i#3 W
Hinhl: La
1, La hinh Iron (Pilea); 2. La hinh mQi giao (Gonostegia); 3, La hinh tim (Dendrocnide); 4, La xe thuy chan vjt
(Girardinia)] 5. L i hinh thuon dai (Boehmeria); 6. La hinh trung (Lecanthus); 7. La hinh bau dye (Debregeara); 8. La l?ch (Elatostema)
Hinh 2: La kem
1-4, La kem nguyen (Boehmeria, Chamabainia, Petelotiella); 5-7, La kem CO thuy (Maoutia. Laportea.
Pilea); 8-9, La kem phan thuy (Debregeasia); 10, L.a kem thanh
c8p (Nanocnide)
Hinh 3: Cum hoa
1, Cym hoa daukhong cuong (Elatostema baviensis); 2-3, Cym hoa dau tren cuong dai (Elatostema
longipes); 4-5, Cym hoa chiim cua dau (4. Oreocnide integrifolia; 5.
Lecanthus peduncularis); 6-7. Cyra hoa bong (Girardinia diversifolia) 8-9. Cym hoa xim co(8. Boehmeria nivea; 9. Dendrocnide urrentissima);
10-11. Cym hoa chuy (10.
Archiboehmeria atrata; W.
Laportea bulbifera)
3. La kem: Hiu nhu cac chi diu cd l i kem trir chi Parietaria, li kem thudng cd mgt, ddi khi hai (Boehmeria, Chamabainia, Nanocnide), nguyen it khi xe thuy (Laportea, Debregeasia, Maoutia). Thudng gip l i kem hinh trimg hay trung rgng (Girardinia, Dendrocnide, Meniscogyne, Procris, Pilea, Lecanthus...), hiem khi hinh diii hay hinh dudng (Petelotiella), chii yeu_^nim trong goc cuong la, ddi khi nim d ben (Pouzolzia, Neodistemon, Urtica, Oreocnide). Li kem thudng sdm ryng, it khi bin (Urtica, Nanocnide, Pilea) (Wnh 2), •
4. Cum hoa: Thudng gip cym hoa mgc d nich l i ddi khi mgc d cic dot khdng l i (Procris), it khi d dinh canh (Neodistemon). Cym hoa chu yeu li hinh xim hai ngi hay xim co (glomemlus), cdn ggi Ii xim dam li dang thoii hoi mgnh do nit ngan cic gidng cua tit c i cic tryc (tryc chinh vi cic tryc ben d mgi cip) ciia xim bg cgp (Boehmeria, Chamabainia, Dendrocnide, Elatostema, Gonostegia, Laportea, Nanocnide, Oreocnide, Parietaria, Petelotiella..), hay hinh chuy (Panicula) (Boehmeria, Dendrocnide, Laportea, Pilea, Procris, Urtica), hoic hinh diu (Capitulum), cd diu khdng cudng, mgc d nich l i (Elatostema, Oreocnide, Procris), dau fren cuong dii (Elatostema, Lecanthus, Meniscogyne), chiiy cua diu (Debregeasia, Oreocnide), ddi khi cd hinh bdng keo dii (nhu hinh dudi sdc) (Boehmeria, Girardinia, Urtica, Neodistemon) (hinh 3).
5. Hoa: Hoa rit nhd, dem tinh, ciing gde hoic khac goc. Hoa diu, bao hoa mau 4 hoic miu 5, hoa khdng cd cinh hoa chi gdm dii hoa hoic hoa trin (Maoutia). Cic hoa thudng tap tmng thanh cym hoa dye vi cym hoa cai, hiem khi cd c i hoa dye v i hoa cii tren ciing mgt cym hoa (Parietaria). Hoa chu yeu cd miu fring xanh ddi khi cd miu hdng (Pilea).
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HOI NGHI KHOA HOC T O A N Q U O C Vg SINH THAI VA TAI NGUYgN SINH VAT LAN THU BA
Hoa difc: Dii thudng rdi gom 4 (5) cinh, ddi khi dinh lai d phia dudi, dinh xe 4 (5) thuy (Meniscogyne, Petelotiella, Chamabainia, Oreocnide), hiem khi dii binh ong (Neodistemon).
Thudng gip dii mdng, deu nhau, hilm khi khdng diu (Lecanlhus), xep Igp hay xep van, da so dai khdng cd simg d lung, ddi khi cd (Chamabainia, Pilea), thudng cd ldng d mit ngoii, Nhj chii ylu cd 4-5, hilm khi 2-3 (Neodistemon, Petelotiella), chi nhj gap lgi frong ny, khi hoa nd bao phin bit tung ra nhu Id so, bao phan 2 d, md dgc, Thudng cd biu tieu giim d giira, hinh ciu (Urtica, Boehmeria, Nanocnide, Procris...), hinh chuy (Dendrocnide, Oreocnide Chamabainia...), hinh dTa cd ldng nhung (Oreocnide, Debregeasia, Maoutia, Parietaria) hoic rit nhd (Elatostema, Lecanthus, Pilea), ddi khi khdng cd (Debregeasia, Petelotiella, Maoutia) (hinh 4).
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Hinh 4: Hoa d\rc
1-4. Hoa dye dai riri (Boehmeria, Elatostema,Uriica); 5-7. Hoa dye di
dinh ir goc (Oreocnide, Meniscogyne. Petelotiella); 8. Hoa dye 2 nhj (Neodistemon); 9-10, Hoa
dye dai CO simg d lung (Pilea, Chamabainia); 11. Hoa dye 3 nhj (Petelotiella); 12-14. Ny hoa dye
(Dendrocnide, Girardinia)
Hinh 5: Hoa cai
1-4. Hoa cii dii rdri (Urtica, Petelotiella. Dendrocnide); 5-8, Hoa
cii dii \i thuy khdng deu (Lecanthus, Pilea); 9. Hoa cii dii
hinh trung (Chamabainia, Boehmeria, Urtica); 10, Dii hinh 6ng (Girardinia); 11. Hoa cii dii c6
simg 6 lung (Nanocnide); 12. Hoa cii cit dijc (Oreocnide); 13-14, Hoa cii dii d ^ g d^u (Oreocnide); 15,
Bhu (Oreocnide)
Hinh 6: Qua
1-2, Q u i d?t ben (Boehmeria, Elatostema Chamabainia); 3, Qua
Iron (Petelotiella); 4, Qui s ^ siii (Urtica, Meniscogyne); 5-7, Qui
nim trong di t6n t^i (Urtica, Nanocnide, Laportea); 8-9, Qui l?ch
(Pilea, Girardinia. Dendrocnide);
10, Qui thing (Petelotiella) 11-12, Qui diu (Oreocnide); 13-14, Qui c6 cinh (Pouzolzia, Gonostegia)
Hoa cai: Dai thudng dinh lai thinh ong hinh trung, cd ring nhd d dinh (Neodistemon, Chamabainia, Boehmeria, Pouzolzia, Girardinia,...) hoic dinh d phia dudi, phia tren xe 4 thuy (Laportea, Nanocnide), ddi khi dii rdi gom (3) 4 cinh khdng diu nhau (Urtica, Nanocnide, Laportea, Pilea, Lecanthus), gin diu (Dendrocnide), ho^c deu (Meniscogyne), cd khi dii rat bd hoic khdng cd (Maoutia, Elatostema, Procris). Dii thudng mdng, hiem khi diy (Laportea, Girardinia, Dendrocnide), cd ldng d m|t ngoai, thudng ldn len cimg qui v i bao xung quanh qui (Boehmeria, Chamabainia, Pouzolzia,...) hoic bao khdng bet qua (Nanocnide, Girardinia, Laportea, Dendrocnide,...). Nhj lep dgng viy mgc doi vdi thuy dii (Elatostema, Meniscogyne, Pilea, Lecanlhus) ho^c khdng cd. Biu thudng hinh frung, nhin hojc cd ldng, bau mgt d, moi d cd 1 noan, noan dinh goc, bau thugng. Biu thudng rdi vdi dii (Urtica, Nanocnide, Boehmeria...) ddi khi dinh vio dii (Oreocnide, Debregeasia), thudng thing it khi nghieng (Dendrocnide). Vdi nhuy ngin (Chamabainia, Parietaria) h o ^ khdng cd (Elatostema, Pilea, Maoutia). Niim nhuy chu yeu hmh biit Idng (penicillatus) (Urtica, Pilea, Elatostema, Procris,...), hinh chi (filiform) (Boehmeria, Pouzolzia, Gonostegia,...), ddi khi cd hinh dau
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HOI NGHI KHOA HOC T O A N Q U O C Vg SINH THAI V A TAI NGUYgN SINH VAT LAN THlJ BA (capitafris) (Nanocnide, Urtica, Chamabainia, Maoutia), hinh bin chai (ligulafris) (Laportea, ^
Dendrocnide, Archiboehmeria), hilm khi cd hmh mdng ngya (Meniscogyne) (hinh 5), \ 6. Qlia: Trong hg Urticaceae chu ylu li qui b l (Achenes), ^hinh biu dye h?p hoic hinh
tnmg. Qui thudng cd dii ton tai bao xung quanh, dai mgng giong nhu qua hgch (Laportea, Uriica, Debregeasia), dai dgng canh (Pouzolzia, Gonostegia), dai dang dau (Oreocnide, Maoutia),... Qua mgc thing (Uriica, Nanocnide, Lecanthus...) hoic mgc Ifch (Laportea, Girardinia, Pilea,...), thudng la qua d?t hinh chir "D", ddi khi trdn (Petelotiella, Lecanthus), cd myn sin (Meniscogyne.) hoic nhin (Boehmeria, Pouzolzia), hilm khi cd long (Maoutia). Niim ^
nhuy tdn tgi d qui (Meniscogyne, Petelotiella), hoic ryng sdm. Qui chi cd 1 hgt (hinh 6). i 1. Hat: Hgt rat nhd, cd kich thudc 1mm, hinh bau dye hoic biu dye hep, vd hat mdng, cd ngi
nhii it hoic nhilu, hilm khi khdng (Dendrocnide, Elatostema). Phdi nhd, thing. |
TAI L i f u THAM KHAO \ 1. Brummitt R. K., 1992: Vascular Plant Families and Genera: 689-804. Royal Botanic
Gardens, Kew.
2. Friis I. B., 1993: The famihes and genera of vascular plant, 2: 612-630. \ 3. Gagnepain F., 1929: Flore Generale de L' Indo-Chme, 5: 828-921.
4. Heywood V.H., 1993: Flowermg plant of tiie world: 95-99.
5. Nguyen Tien Hifp, 2003: "Urticaceae". Danh lyc cic loii thye vat Vift Nam, 2: 209-226, NXB Ndng nghifp. Hi Ngi.
6. PhamHoangHg,2000:CaycdViftNam,2:581-607,NXB. Tre. Tp.HCM.
7. Hutchinson J., 1969: The families of flowermg plants, 1: 40- 100, 202-203.
8. Takhtajan A., 1996: Diversity and classification of flowering plants: 236-239.
SOME MORPHOLOGICAL C H A R A C T E R I S T I C S T O IDENTIFY G E N E R A O F U R T I C A C E A E IN V I E T N A M
DUONG THI HOAN SUMMARY
The Urticaceae in the flora of Vietnam has 21 genera and about 100 species. This article presents some systematic information about major morphological characteristics (leaves, inflorescences, male flowers, female flowers, fmits and seeds). Leaves altemate or opposite, stipules present, rarely absent; leaf blades simple. Inflorescences cymose, paniculate, racemose, spicate, or cluster-capitate, usually formed from glomemles, sometimes crowded on common enlarged cuplike or discoid receptacle, rarely reduced into a single flower, Male flowers:
stamens as many as and opposite to perianth lobes, filaments inflexed in bud; anthers 2-locular, opening lengthwise, mdimentary ovary often present. Female flowers: perianth lobes free or coimate, usually enlarged in fmit and persistent, occasionally absent; staminodes scarious, opposite to the perianth lobes, or absent. Ovary mdimentary in male flowers, sessile or shortly stipitate, free or adnate to the perianth; 1-locular, ovule solitary, erect from the base; style simple, or absent; stigma diverse, capitate, penicillate-capitate (bmshlike), subulate, filiform,liguIate, or peltate. Fmit usually a dry achene, sometunes a fleshy dmpe, often enclosed by the persistent perianth. Seed solitary, endosperm usually present; embryo straight; cotyledons ovate elliptical or orbicular.
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