Revista Árvore ISSN: Universidade Federal de Viçosa Brasil

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1 Revist Árvore ISSN: Universidde Federl de Viços Brsil Crvlho Gonçlves, José Frncisco de; Souz Lim, Rent Brg; Vrmes Fernndes, Andrei; Lim e Borges, Edurdo Euclydes de; Silveir Buckeridge, Mrcos Physiologicl nd biochemicl chrcteriztion of the ssi plm (Euterpe olerce Mrt.) during seed germintion nd seedling growth under erobic nd nerobic conditions Revist Árvore, vol. 34, núm. 6, noviembre-diciembre, 21, pp Universidde Federl de Viços Viços, Brsil Avilble in: How to cite Complete issue More informtion bout this rticle Journl's homepge in redlyc.org Scientific Informtion System Network of Scientific Journls from Ltin Americ, the Cribben, Spin nd Portugl Non-profit cdemic project, developed under the open ccess inititive

2 Physiologicl nd biochemicl chrcteriztion of PHYSIOLOGICAL AND BIOCHEMICAL CHARACTERIZATION OF THE ASSAI PALM (Euterpe olerce MART.) DURING SEED GERMINATION AND SEEDLING GROWTH UNDER AEROBIC AND ANAEROBIC CONDITIONS 1 José Frncisco de Crvlho Gonçlves 2, Rent Brg Souz Lim 2, Andrei Vrmes Fernndes 2, Edurdo Euclydes de Lim e Borges 3 e Mrcos Silveir Buckeridge 4 ABSTRACT Physiologicl nd biochemicl spects of ssi plm during seed germintion nd erly seedling growth were investigted. Seeds collected from plnts growing in flooded nd uplnd forests were used to determine the influence of normoxic (erobic) nd noxic (nerobic) conditions in germintion nd the initil nd verge time of development in the roots nd shoots. After 75 dys, seedlings germinted under normoxi were trnsferred to trys nd submitted to flooding. Seed reserves (lipids, proteins, soluble sugrs nd strch) were monitored for quiescent nd germinted seeds mintined under normoxic nd noxic conditions, s well s fter 5, 1 nd 2 dys of seedling growth. Alcohol dehydrogense (ADH) ctivity ws quntified in roots nd leves of seedlings without or with flooding (prtil nd totl). Seeds were not ble to germinte under noxi. Different strtegies of storge mobiliztion of lipids, proteins, soluble sugrs nd strch were observed in seeds of ech environment. ADH ctivity ws induced by noxi, with the highest level observed in the leves. This study showed tht, under normoxic conditions, the best developmentl performnce of ssi plm seeds, from flooded or uplnd forest res, during germintion ws ssocited with primry metbolites mobiliztion nd seedling flooding tolernce with incresed ADH ctivity. We conclude tht the ssi plm is well dpted to the noxic conditions provoked by flooding. Key words: Alcohol dehydrogense, Anoxi nd normoxi nd Storge mobiliztion. CARACTERIZAÇÃO FISIOLÓGICA E BIOQUÍMICA DURANTE A GERMINAÇÃO DE SEMENTES E O CRESCIMENTO DE PLÂNTULAS DE AÇAÍ (Euterpe olerce MART.) SOB CONDIÇÕES AERÓBICA E ANAERÓBICA. RESUMO Aspectos fisiológicos e bioquímicos durnte germinção de sementes e crescimento inicil de plântuls de çí form investigdos. Sementes coletds de plnts crescendo n várze e n terr firme form utilizds pr determinr influênci ds condições de normoxi (eróbic) e de noxi (neróbic) n germinção e no tempo inicil e médio do desenvolvimento d riz e prte ére. Após 75 dis, plnts germinds sob normoxi form trnsferids pr condições de lgmento. A quntificção ds reservs d semente (lipídios, proteíns, çúcres solúveis e mido) foi monitord em sementes quiescentes e germinds em condições de normoxi e nóxics, bem como pós 5, 1 e 2 dis de crescimento ds plnts. A tividde d enzim desidrogense lcoólic (ADH) foi quntificd em rízes e folhs de plnts submetids o lgmento (prcil ou totl) ou sem lgmento. As sementes não germinrm em condições de noxi. Ns sementes, diferentes estrtégis de mobilizção de reservs (lipídios, proteíns, çúcres solúveis e mido) form observds, ns condições estudds. A tividde d ADH foi induzid em condições de noxi, sendo mior tividde observd ns folhs. Este estudo demonstrou que, sob condições eróbics, o melhor desempenho ds sementes de çí, d várze ou em terr firme, durnte germinção foi ssocido à mobilizção de reservs e à tolerânci ds plântuls o lgmento com o umento d tividde d ADH. Concluiu-se que plmeir çí é plnt bem dptd às condições de noxi provocds pelo lgmento. Plvrs-chve: Desidrogense lcoólic, Anoxi e normoxi e Mobilizção de reservs. 1 Recebido em e ceito pr publicção em Instituto Ncionl de Pesquiss d Amzôni, Lbortório de Fisiologi e Bioquímic Vegetl, Mnus-AM, Brsil. E-mil: <jfc@inp.gov.br>, <rentbsl@hotmil.com> e <vrmes@inp.gov.br>. 3 Universidde Federl de Viços, Deprtmento de Engenhri Florestl, UFV, Brsil. E-mil: <elborges@ufv.br>. 4 Universidde de São Pulo, Deprtmento de Botânic, São Pulo-SP, São Pulo-SP, Brsil. E-mil: <msbuck@usp.br>. Revist Árvore, Viços-MG, v.34, n.6, p , 21

3 146 GONÇALVES, J.F.C. et. l. 1. INTRODUCTION The periodic flooding in the centrl Amzonin region is responsible for deep chnges in the environmentl conditions. In this region, pproximtely 3, km 2 re covered with flooded forests; clssified genericlly s sesonlly-flooded nd permnently flooded forests, which occupy res of 2, nd 1, km 2, respectively (Junk, 1993). However, the construction of hydropower sttions hs considerbly enlrged the extension of res occupied by wter, provoking hrmful environmentl effects to the Amzonin rinforest (Fernside, 22). Besides the flooding of lrge res, hydropower construction leds to the estblishment of rods nd/or power lines, which provokes frgmenttion nd destruction of the forest. Therefore, the estblishment of mesures ble to help to decrese the environmentl impcts of hydropower development re highly required.. In this context, plnts tht show dpttions to environmentl flooding re of gret importnce for the restortion of res ffected by hydropower dms. According to Prolin et l. (24), combintions of dpttions of seedling growth nd development nd seed germintion result in vriety of growth strtegies of trees of the centrl Amzonin regions. These led to specific species distributions nd zontions long the flooding grdient, nd within Amzonin floodplin systems with different environmentl conditions, depending on the qulity of the flooding rivers. Regrding seed germintion, Wittmnn et l. (27) concluded tht the contct with river wter did not disturb it but, on the contrry, enhnced germintion in the species Slix mrtin, Pseudobombx mungub, Leti corymbulos nd Vitex cymos. Among Amzonin plnts, the ssi plm (Euterpe olerce Mrt.); one of mny commercilly importnt species endemic to the region, is distinguished by its high level of tolernce to locl biotic stress conditions; being cpble of dpting its growth to sesonllyflooded soils (Oliveir et l., 22). As observed for some plnts growing under flooding conditions, Plme plnts develop, in their roots, specil structures clled pneumtophores (Clbo et l., 1998). Plnt oxygen sttus cn be defined s normoxic (erobic conditions), hypoxic (low oxygen vilbility), nd noxic (nerobic conditions). Plnt species growing under noxi exhibit biologicl chnges tht induce ntomicl, biochemicl nd physiologicl dpttions (Wldhoff et l., 1998; Mores et l., 21; Souz nd Sodek, 22). In contrst, species sensitive to flooding my exhibit some or ll of the following responses: interruption of vegettive nd reproductive growth; reduction of stomtl conductnce; lef chlorosis nd bscission; nutritionl deficiency, ccumultion of toxic substnces in the roots; nd even plnt deth (Crvlho nd Ishid, 22; Arrud nd Clbo, 24). Under flooding stress, the composition, quntity nd mobiliztion of seed reserves (lipids, proteins, soluble sugrs, nd strch) nd the enzyme ctivities relted to ATP production through glycolysis nd fermenttion re crucil for erly seedling growth under noxic conditions (Ricrd et l., 1994; Dolferus et l., 23). Proteins which re synthesized s specific responses to nerobiosis re clled the nerobic polypeptides. Most of the known proteins ccumulted in plnts under noxi re enzymes relted to sucrose nd strch degrdtion, glycolysis nd ethnol fermenttion (Lio nd Lin, 21). Among them, lcohol dehydrogense (ADH) is n enzyme tht ctlyzes the reduction of cetldehyde to ethnol while oxidizing NADH to NAD +. In plnts, incresing ctivity of this enzyme hs been observed for long time nd is thought to be relted to flooding (Crwford, 1967; Wignrjh et l., 1976). The formtion of ethnol is thought to help the plnt cell to llevite the deleterious effects provoked by lctte ccumultion (cytoplsmic ph cidifiction) (Bry et l., 2). Considering tht the knowledge bout the biochemicl processes involved in seedling estblishment re key to understnding how these plnt species dpt to their respective environments, we tried to chrcterize the mobiliztion of storge compounds (strch, soluble sugr, lipids nd proteins) nd the ctivity of lcohol dehydrogense during seed germintion nd seedling growth of E. olercee either under flooded or uplnd forests conditions. 2. MATERIALS AND METHODS 2.1 Plnt mteril, seed germintion nd seedling growth Seeds of ssi plm were collected from 1 plnts growing in flooded nd uplnd forest conditions t the Pedro de Mour Bse for Geologic Opertions, Revist Árvore, Viços-MG, v.34, n.6, p , 21

4 Physiologicl nd biochemicl chrcteriztion of º 53 S nd 65º 11 W (Petrobrs-BR), locted 6 km from Mnus (AM) Brzil. Seeds were surfce sterilized with.5% (v/v) sodium hypochlorite for 1 min nd then plced to germinte in trys contining wshed snd. Seed germintion ws recorded during the following tretments: ) submergence (wter level ± 4 cm), nd b) under normoxic conditions (control). For ech tretment three replictes of 25 seeds were used. Germintion tests were crried out t 3 ± 2 C nd reltive ir humidity of 9%, considering botnicl nd technologicl criterion of germintion (rdicle emission or complete plnt, respectively), ccording to Lbouriu (1983) nd Brsil (1992). Seeds of ssi plm from flooded nd uplnd forest res were germinted (with or without flooding) nd were monitored dily, for 75 dys nd the following vribles were followed: ) Emergence velocity index (EVI), b) Initil germintion time (IGT), c) Averge germintion time (AGT) nd d) percentge of germintion. Seventy five dys fter the beginning of the germintion experiment, seedlings from seeds germinted under normoxi (seeds were not ble to germinte under noxi) were trnsferred, in three groups of 36 plnts, to trys contining mixture of snd nd soil (1:1). To test the influence of normoxi nd noxi on the mobiliztion of reserves during erly seedling growth, ssi plm seedlings were submerged in wter level of 1 cm bove the level of the seedlings. 2.2 Extrction nd quntifiction of seed compounds The mounts of lipids, proteins, nd crbohydrtes were monitored in quiescent nd germinted seeds (75 dys) with 5, 1 nd, 2 dys of growth of the seedlings. For the quntifiction of seed primry metbolites three replictes of seeds were tested for ech environment. Unless otherwise stted, ll the nlyses were performed using dried plnt mteril (75 o C). Lipid extrction ws performed using the Soxhlet pprtus. Seeds nd seedlings lipid contents were determined following the A.O.A.C recommendtion (1984). Proteins were extrcted ccording to Pssos (1996) using the hot lcohol method. Protein concentrtion ws determined ccording to Brdford (1976), using bovine serum lbumin (BSA) s stndrd. For soluble sugrs determintion, seeds were crushed with 95% (v/v) ethnol, following centrifugtion t 3,5 x g, for 1 min t 25 C. The superntnt ws stored nd the pellet ws re-extrcted with 8% (v/v) ethnol (6ºC) nd centrifuged s mentioned before (Buckeridge & Dietrich, 1996). The superntnts were combined for the determintion of soluble sugrs, nd the pellet suspended in 1 ml of 35% (v/v) perchloric cid. After centrifugtion, the superntnt ws collected for the quntifiction of strch. Soluble sugrs nd strch were estimted by the nthrone technique (625 nm) using glucose s stndrd (Sigm ) (Morris, 1948). 2.3 Extrction nd determintion of lcohol dehydrogense ctivity ADH (E.C ) Enzyme ctivity ws mesured in leves nd roots of ssi plm seedlings cultivted under the following conditions: ) control (without flooding), b) prtil flooding (± 2 cm, only roots submerged), nd c) flooding (± 18 cm, entire plnt submerged). Leves nd roots were collected for enzyme extrction with three replictes from seedlings cultivted during 2, 4, 8 nd 16 dys. Plnt mteril (1 g) ws homogenized in 5 mm Tris-HCl (ph 6.8) contining 2.5 mm mgnesium chloride, 1 mm EDTA,.15 ml of glycerol,.5 ml â- mercptoethnol 2 mm (v/v) nd distilled wter to finl volume of 1 ml. After centrifugtion (5 x g, 1 min, 4 C), liquots of 1 ìl were dded to the rection medium contining 32 ìl of 5 mm Tris-HCl (ph 8.9), 1 ìl ethnol, 1 ìl NAD + (1mg ml -1 ), nd distilled wter to finl volume of 2.7 ml. After incubtion t 3 C for 15 min, the bsorbnce ws monitored (Genwy Instrument 615, Essex, Englnd) t 34 nm (Menezes Neto et l., 1995). ADH ctivity ws ssyed by following the reduction of NAD +. The ssy ws strted by dding.4 ml of 5% ethnol nd A 34 ws recorded every 3 s during 18 s. 2.4 Experimentl design nd sttisticl nlysis The experimentl design ws completely rndomized with three tretments nd twelve replictes (seedlings). The results of the germintion experiments nd quntifiction of orgnic reserves were submitted to vrince nlysis (ANOVA) followed by the Tukey test (P d.5), using Sttistic for Windows Version 6 (SttSoft Inc., 23 Est 14 th Street, Tuls, OK, USA). 3. RESULTS AND DISCUSSION Seventy five dys fter the beginning of the germintion experiment, more thn 95% germintion ws reched in ll tretments (Tble 1). We obtined 145 seedlings fter germintion under normoxic conditions, 73 of them being from plnts growing in flooded environments nd 72 from plnts growing in uplnd forests conditions. When submitted to noxic Revist Árvore, Viços-MG, v.34, n.6, p , 21

5 148 GONÇALVES, J.F.C. et. l. conditions ssi plm seeds did not germinte. However, it is known tht the ssi plm occurs in flooded environments, nd probbly begins the germintion process under conditions of normoxi during the dry period (Menezes Neto et l., 1995). This suggests tht under noxic conditions, the seeds of ssi plm re likely to be unble to synthesise nd/or ctivte enzymes necessry for seed germintion. Okmoto & Joly (2) studying the germintion of Ing sessilis (Vell.) Mrt. seeds submitted to conditions of normoxi, hypoxi, nd noxi, found tht 4% of the seeds germinted under hypoxi. 3.1 Comprison between seed germintion of ssi from different environments Assi plm seeds collected in uplnd forests showed the highest index of emergence velocity (1.9), the shortest time for rdicle emergence (6 dys), s well s the lowest vlues for verge time of rdicle nd shoots emission (17 nd 22 dys, respectively). In comprison, seeds collected in the flooded re showed n emergence velocity index of.8, n initil time for germintion of 16 dys nd n verge time of pproximtely 34 nd 46 dys for the roots nd shoots emission, respectively (Tble 1). Nevertheless, it is importnt to stress tht there ws no difference in the finl percentge of germintion between seeds collected in flooded res (98%) or uplnd forests (96%). Under nturl conditions in the forest, ssi seeds cn tke 1-11 months to germinte. Under lbortory conditions the percentge of seed germintion cn rech c. 9%, but under nturl conditions no more thn 6% of ssi seeds re ble to germinte (Bovi et l., 1989). Our results re consistent with the hypothesis tht fster seed germintion of flood-intolernt seeds might be strtegy with which plnts tke dvntge of fvorble conditions tht led to seedling estblishment. During seed germintion, crbon cn be mobilized either in the form of crbohydrtes or lipids, strch being one of the most importnt storge polyscchrides, followed by the cell wll polyscchrides (Buckeridge et l., 24). Tble 2 shows tht the concentrtion of strch ws higher in ssi seeds collected in flooded thn in uplnd forests. A possible explntion for this difference is tht plnts growing in flooded hbitt could hve ccumulted more reserves (crbohydrtes) s n evolutionry dpttion. This is likely to hve hppened becuse the chnge from erobic to nerobic respirtion cn severely ffect the vilbility of energy in the plnt (Junk, 1989; Drew, 1997; Figueiredo et l., 21; Pontes et l., 22). Tble 2 shows tht in the uplnd forests, some strch mobiliztion occurred, with the decrese round 4% fter germintion. In the flooded re, however, no difference ws observed in strch levels. This suggests possible role of strch s one of the crbon storge compounds in ssi seeds. The concentrtion of soluble sugrs ws much higher in drier thn in flooded res, wheres lipids were not different in seeds from the two environments. However, for proteins decrese of pproximtely Tble 1 Comprison between ssi plm seed germintion from different environments under normoxic conditions, using botnicl nd technologicl criteri. Emergence velocity index (EVI), Initil germintion time (IGT), Averge germintion time (AGT) nd percentge of germintion. Tbel 1 Comprção entre germinção de sementes de çí de deferentes mbientes sob condições de normoxi, usndo os critérios botânico e tecnológico. Índice de velocidde de germinção (IVE), tempo inicil de germinção (TIG), tempo médio de germinção (TMG) e porcentgem de germinção. Prmeters Flooded Uplnd forests Botnicl Technologicl Botnicl Technologicl EVI.8 ±.1B.6 ±.1B 1.9 ±.2A 1. ±.13Ab IGT 16. ± 4.2A 22.5 ± 13.4A 6. ±.Bb 13.5 ±.7A AGT 33.9 ± 6.8Ab 46.1 ± 4.2A 17.3 ± 1.1B 22.4 ± 3.7B Germintion (%) 98. ± 2.A 96. ±.A 96. ±.A 96. ±.A Men ± S.D. followed by sme cpitl letters for environments (Flooded or uplnd forests) nd lower cse letter for criteri of germintion (botnicl or technologicl) re not significnt t P d.5 using the Tukey test. Médi ± D.P. seguidos por letr miúscul mesmo pr mbientes (florests inundds ou de sequeiro) e letrs minúsculs pr o critério de germinção (botânic ou tecnológico) não são significtivos P d,5, pelo teste de Tukey. Revist Árvore, Viços-MG, v.34, n.6, p , 21

6 Physiologicl nd biochemicl chrcteriztion of Tble 2 Strch, soluble sugrs, lipids, nd proteins content in ssi plm seeds collected from plnts in flooded nd uplnd forests environments, before (quiescent) nd fter 75 dys of germintion (germinted). Tbel 2 Conteúdo de mido, çúcr solúvel, lipídios e proteíns em sementes de çí coletds de plnts em mbientes lgdos e não lgdos, ntes (quiescente) e depois de 75 dis de germinção (germinds). Metbolites Flooded Uplnd forests Quiescent Germinted Quiescent Germinted Strch (%) 75.9 ± 7.9A 75.2 ± 4.A 54.6 ± 2.2B 33.5 ±.7Bb Soluble sugrs (%) 1.3 ± 2.3B 1.8 ± 2.8B 3.9 ± 6.9A 3.7 ± 3.4A Lipids (%) 2.4 ±.3A 1.7 ±.2A 2.6 ± 1.A 1.5 ±.2A Proteins (%) 4.4 ±.3A.9 ±.1Bb 4.7 ±.5A 1. ±.1Bb Men ± S.D. followed by sme cpitl letters for environments (flooded or uplnd forests) nd lower cse letter for criterion of germintion (quiescent or germinted) re not significnt t P d.5 using the Tukey test. Médi ± D.P. seguidos por um letr miúscul mesmo pr mbientes (sequeiro ou irrigdo florests) e letrs minúsculs pr o critério de germinção (quiescente ou germinds) não são significtivos P d,5, pelo teste de Tukey. 8% ws observed in quiescent seeds (flooded nd uplnd forests) when compred with germinted seeds. These results indicte tht the reserves of nitrogen re probbly in the form of proteins tht come from degrdtion of storge proteins. Protein mobiliztion plys mjor role s source of nitrogen in the nutrition of the embryo during the germintion of seeds of Euphorbi heterophyll s suggested by Sud nd Giorgini (2). 3.2 Effect of oxygen deficiency on seedling growth As ssi plm seeds did not germinte under noxic conditions, we decided to test the influence of noxic nd normoxic conditions during erly seedling growth. Anlyses of storge (lipids, proteins, soluble sugrs, nd strch) reveled tht their mobiliztion were influenced by seed source (flooded nd uplnd forests) nd oxygen vilbility (Figure 1A-D). Lipid contents underwent progressive reduction 2 dys fter germintion (Figure 1A). According to Pert et l. (1997), the mobiliztion of lipids in flooded plnts is probbly less effective for nerobic respirtion due to the high demnd of oxygen necessry for this type of metbolism. For proteins, reduction ws observed until 5 dys fter germintion, followed by n increse in ll tretments fter 2 dys, with higher levels presented in seedlings produced from seeds collected in uplnd forests (Figure 1B). Under normoxic conditions, the contents of soluble sugrs in seedlings incresed pproximtely 4.5 times by the end of the experiment (Figure 1C). Strch content levels tripled until 5 dys fter germintion in seeds collected from uplnd forests, followed by progressive reduction fter 2 dys (Figure 1D). One possible hypothesis to explin the mobiliztion of strch might be relted to higher demnd of crbohydrtes due to higher growth rtes observed. This probbly incresed the survivl of seedlings under conditions of limited oxygen vilbility (Guglielminetti et l., 1995). Our observtions re consistent with the fct tht ssi plm seedlings disply some tolernce to flooding, which is probbly ssocited with strch mobiliztion. In study of different cerel species, Pert et l. (1997) found tht rice seeds were the only ones cpble of mobilizing strch under noxic conditions. Furthermore, the ccumultion of soluble sugrs in developing seedlings under noxic conditions is likely to be importnt for ATP production (Rodrigues et l., 25). According to Kolb et l. (22), in Neotropicl plnt species, constitutive prmeters of seeds such s size, nture nd mount of reserves only prtly influence resistnce to flooding wheres prmeters relted to metbolic efficiency under stress conditions pper to be more importnt. The ADH ctivity ws ssyed during erly-seedling growth of the ssi plm under erobic (control) nd nerobic conditions (totl nd prtil flooding) (Figure 2). After 2 dys, ADH ctivity ws strongly induced in seedling leves growing under prtil flooding conditions, wheres under complete flooding ADH ctivity remined high for 4 dys (n increse of pproximtely 18 times). Subsequently, ADH ctivity ws drsticlly reduced to levels similr to those observed in the control (Figure 2A). In comprison to the leves, ADH ctivity in the roots ws only wekly induced, being the highest level observed in roots under totl flooding fter 2 dys (Figure 2B). Revist Árvore, Viços-MG, v.34, n.6, p , 21

7 15 GONÇALVES, J.F.C. et. l. 3 A 15 C Lipids (%) 2 1 Soluble sugr (% ) Time (dys) Time (dys) Proteins (%) B Strch (% ) D Time (dys) Time (dys) Figure 1 Vrition in the levels of lipids (A), proteins (B), soluble sugrs (C), nd strch (D), in quiescent () nd germinted seeds (fter 75 dys) of the ssi plm fter 5, 1 nd 2 dys of seedling growth, collected from plnts growing in the following environments: flooded control ( ), plnts from the flooded tht were experimentlly flooded (.), uplnd forests control ( ) nd uplnd forests with flooding ( ). Figur 1 Vrição nos níveis de lipídios (A), proteíns (B), çúcr solúvel (C) e mido (D), em sementes quiescentes () e germinds (depois de 75 dis) de çí pós 5, 1 e 2 dis de crescimento d plântul, coletds de plnts crescids em mbientes: flooded control ( ), plnts from the flooded tht were experimentlly flooded ( ), uplnd forests control ( ) nd uplnd forests with flooding ( ).. After 4 dys, ADH ctivity in the leves reduced to levels similr to those of the control group. High levels of ADH ctivity in plnts under nerobiosis hve been ssocited with tolernce to flooding in plnts (Lio nd Lin, 21). In Echinochlo crus-glli seedlings growing under noxi the ctivity of enzymes ssocited to nerobic metbolism (including ADH) incresed fold compred to their ctivity under erobic conditions (Fuko et l., 23). According to Souz nd Sodek (22), the increse in the ADH ctivity in response to noxi contributed to the mintennce of ATP synthesis gurnteeing seedling survivl. Our results indicte tht seed germintion nd seedling growth disply fetures tht re comptible with certin degree of tolernce to flooding, suggesting tht the ssi plm is quite well dpted to the Amzonin environmentl conditions regrding the chnges in wter levels in the region. Revist Árvore, Viços-MG, v.34, n.6, p , 21

8 Physiologicl nd biochemicl chrcteriztion of FW ) ADH ctivity (mmol.min mol -1 l g b b b c b B b c c A BOVI, M.L.A., SPIERING, S.H. & MELO, T.M. Temperturs e substrtos pr germinção de sementes de plmiteiro e çizeiro. In Anis do Segundo Congresso sobre Tecnologi de Sementes Florestis. Atibi, São Pulo. p. 43,1989. BRADFORD, M. M A rpid nd sensitive method for the quntifiction of microgrm quntities of protein utilizing the principle of protein-dye binding. Anlyticl Biochemistry 72: , BRASIL. Ministério d Agricultur e Reform Agrári. Regrs pr nálise de sementes. Brsíli: CLAV/DNDV/SNAD/MA. 365p, Time (dys) Figure 2 Alcohol dehydrogense (ADH) ctivity in the leves (A) nd roots (B) of ssi plm seedlings cultivted during 2, 4, 8 nd 16 dys. Plnt mteril ws obtined from plnts growing in uplnd forests nd mintined in the following tretments: flooding ( ), prtil flooding ( ), nd control ( ). Figure 2 Atividde d enzim álcool desidrogense (ADH) em folhs (A) e rízes (B) de plântuls de çí cultivds durnte 2, 4, 8 e 16 dis. O mteril foi obtido de plnts crescendo em mbientes não lgdos e mntidos nos trtmentos: lgdo ( ), prcilmente lgdo ( ) e controle ( ). 4. ACKNOWLEDGEMENTS The uthors thnk the Ntionl Institute of Amzonin Reserch nd members of Lbortory of Plnt Physiology nd Biochemistry (MCT-INPA) for their technicl ssistnce during the nlysis. Finncil support for this study ws provided by the CAPES-PRODAD nd FINEP-CTPETRO. J.F.C.GONÇALVES nd M.S.BUCKERIDGE cknowledge fellowship grnted by the Ntionl Council for Scientific nd Technologicl Development - CNPq. 5. REFERENCES ASSOCIATION OF OFFICIAL ANALYTICAL CHEMISTS - A.O.A.C. Officil methods of nlysis. 15.ed. Wshington, D. C.:1984. ARRUDA, G.M.T. & CALBO, M.E.R. Efeitos d inundção no crescimento, trocs gsoss e porosidde rdiculr d crnúb (Copernici prunifer (Mill.) H.E. Moore). Act Botânic Brsílic 18 (2): , 24. BRAY, A.B., BAYLEY-SERRES, J. & WERETILNYK, E. Responses to biotic stresses. In Biochemistry & Moleculr Biology of Plnts (B. Buchnn, W. Gruissem & R. Jones eds). Americn Society of Plnt Physiologists. USA. p , 2. BUCKERIDGE, M. S. & DIETRICH, S.M.C. Mobilistion of the rffinose fmily oligoscchrides nd glctomnnn in germinting seeds of Sesbni mrgint Benth. (Leguminose Fboidee). Plnt Science 117: 33-43, BUCKERIDGE, M. S., SANTOS, H. P., TINÉ, M. A. & AIDAR, M.P.M. Mobilizção de Reservs. In: Germinção do básico o plicdo. Alfredo Gui Ferreir & Fbin Borgheti (Eds). Artmed, Porto Alegre p , 24. CALBO, M.E.R.; MORAES, J.P.V. & CALBO, A.G. Crescimento, condutânci estomátic, fotossíntese e porosidde do buriti sob inundção. Revist Brsileir de Fisiologi Vegetl 1: 51-58, CARVALHO, C.J.R. de & ISHIDA, F.Y. Resposts de pupunheirs (Bctris gsipes Kunth) jovens o lgmento. Pesquis Agropecuári Brsileir 37: , 22. CRAWFORD, R. M. M. Alcohol dehydrogense ctivity in reltion to flooding tolernce in roots. Journl of Experimentl Botny 18: , DOLFERUS, R., KLOK, E. J., DELESSEST, C., WILSON, S., ISMOND, K. P., GOOD, A. G., PEACOCK, W. J. & DENNIS, E. Enhncing the nerobic response. Annls of Botny 91: , 23. Revist Árvore, Viços-MG, v.34, n.6, p , 21

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