Investigation of photosynthesis status of sunflower plants up-taking different forms of Selenium

Ad ances in Plan s & Ag icul u e Resea ch In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium Submi Manusc ip | h p://medc a eonline.com Abb e ia ions: Chl: Chlo ophyll; PS: Pho osyn he ic Sys em; E: T anspi a ion Ra e; Fm: Maximal luo escence yield o he da k- adap ed s a e; F0: Minimal luo escence yield o he da k-adap ed s a e; F /Fm: Maximal quan um yield o PSII pho ochemis y; F / F0: Po en ial pho osyn he ic capaci y; F : Va iable luo escence; Pn: Pho osyn hesis a e In oduc ion T ace selenium (Se) de e mina ion in en i onmen al and ood samples is o g ea impo ance, because o playing an impo an ole in biologic and physiologic body unc ions (as an essen ial nu ien ) o humans, animals, mic oo ganisms, and has also been ound o plan s. The chemical p ope ies o Se a e ela i ely simila o hose o sulphu . I s specia ion is highly dependen on he pH and Eh [1,2] inducing a complex beha iou and a la ge a ie y o selenium compounds in he en i onmen . Se has ou s able edox s a es: selenide (Se (-II)), elemen al selenium (Se (0)), seleni e (Se (IV)) and selena e (Se (VI)) [3,4]. As an essen ial ace mine al, Se is indispensable o cells o unc ion p ope ly. Two ino ganic species, seleni e (SeIV) and selena e (SeVI) a e impo an in biogeological and biochemical cycle o Se, bu hey exhibi di e en biochemical p ope ies and hei ene gy consump ion du ing up ake and me abolism a e di e en [5,6]. Se is cha ac e ized by i s ela i ely na ow concen a ion ange esul ing in de iciency, essen iali y and oxici y [7]. Fu he mo e, selenium le els in he en i onmen al and ood samples a e gene ally lowe han de ec ion limi s o he con en ional echniques epo ed o i s de e mina ion [8]. To coun e ac his p oblem, many s udies demons a ed ha p ope doses o Se compounds can use o inc ease he Se con en in he edible pa s o c ops [9-11], hence in his s udy we selec ed sun lowe (Helian hus annuus L.) because i is widely used plan s cul u ed h oughou he wo ld, is impo an sou ces o Se o human die [12]. In addi ion, lea es con ain a ious pigmen s (chlo ophylls and ca o enoids) ha ha e he p ope y o abso b ligh ene gy. This ene gy can be used o pho osyn hesis (pho ochemis y) o e-emi ed as ligh -chlo ophyll luo escence [13] by measu ing he chlo ophyll luo escence, in o ma ion abou changes in he e iciency o pho ochemis y is gained [14]. Fluo escence can be quan i ied by exposing a lea o ligh o de ined wa eleng h and measu ing he amoun o ligh e-emi ed a longe wa eleng hs [15,16]. In ecen yea s, he echnique o Chlo ophyll luo escence (Chl- luo escence) has become ubiqui ous in plan ecophysiology s udies. Va iable luo escence was ound o be a e y sensi i e ool, gi ing ea ly indica ions o he gene al indica ions o he pho osyn he ic appa a us. The use o his simple echnique epo s di ec ly on he pho ochemical ac i i y o chlo oplas s [17] and pho osyn hesis is one o he p ima y me abolic p ocesses ha de e mines c op p oduc ion and lowe pho osyn he ic ac i i y includes dec eased pho ochemical e iciency o pho osyn he ic sys em II (PSII) [18] which ep esen s he mos ulne able complex o he pho osyn hesis appa a us [19] and un il now in luence o Se on chlo ophyll luo escence and ela ionship be ween he issue Se concen a ion and pho osyn he ic sys em in p oducing Se- ich sun lowe has no been epo ed. Volume 3 Issue 1 - 2016 1Depa men o Ag icul u al and Food Sciences and En i onmen al Managemen , Uni e si y o Deb ecen, Hunga y 2Depa men o Ag icul u al Bo any, Hunga y *Co esponding au ho : Fa zaneh Ga ousi, Depa men o Ag icul u al and Food Sciences and En i onmen al Managemen , Ins i u e o Food Science, Uni e si y o Deb ecen, H-4032 Deb ecen Böszö ményi s . 138, Hunga y, Tel: +36 30 7597506; Email: Recei ed: Oc obe 08, 2015 | Published: Janua y 20, 2016 Resea ch A icle Ad Plan s Ag ic Res 2016, 3(1): 00083 Abs ac Consump ion o ood p oduc s low in Selenium (Se) such as China, UK, Eu ope, Aus alia and New Zealand can esul in a popula ion wi h a lowe daily in ake o Se. Hence, he e is a need o inc ease he o ganic Se concen a ion in ood p oduc s in Se-de icien egions. Acco dingly, con olling he Se up ake, me abolism, and dynamic changes in plan s will be impo an o eaching o adequa e me hods o bio o i ica ion. In his ega d, in p esen s udy, chlo ophyll luo escence and pho osyn he ic pa ame e s o old and young lea es o sun lowe plan s ha had been ea ed by sodium seleni e and sodium selena e a di e en concen a ions in nu ien solu ion, we e measu ed. The esul s showed ha he esponse o expe imen ed sun lowe s a 0.1 and 0.3 mg L-1 SeVI concen a ion, o almos all o he conside ed pa ame e s was signi ican ly be e in compa ison wi h con ols samples. I means he applica ion o 0.1 and 0.3 mg L-1 SeVI enhanced pho osyn hesis by inc easing he pho osyn hesis a e (Pn) and he anspi a ion e iciency (E). Also, Se ea men enhanced he ac i i y o he pho osyn he ic sys em by inc easing F /Fm and F /Fo. Then, p esen s udy p o es he chlo ophyll luo escence o pho osyn he ic pa ame e s can be used o de e mining he su iciency o Se ea men du ing he p oduc ion o sun lowe by Se. Keywo ds: Sodium seleni e; Sodium selena e; Pho osyn hesis; Sun lowe In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium 2/8 Copy igh : ©2016 Ga ousi e al. Ci a ion: Ga ousi F, Ko ács B, Ve es S (2016) In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium. Ad Plan s Ag ic Res 3(1): 00083. DOI: 10.15406/apa .2016.03.00083 The e o e, in his wo k we ied o expose sun lowe plan s o Se in bo h o ms o sodium seleni e and sodium selena e and in es iga e so-called issues. Ma e ials and me hods Ma e ials Sodium seleni e and sodium selena e we e ob ained om Sigma-Ald ich L d. (Poole, UK). Gene al plan p opaga ion Sun lowe (Helian hus annuus L. c . A ena PR) as a dico yledons plan was chosen o ou esea ch. Disin ec ed sun lowe seeds we e geo opically ge mina ed be ween mois il e pape s in 22°C. Sun lowe seedlings wi h 1.5-2.0 cm hypoco yl we e placed in o ae a ed nu ien solu ion po s. Sun lowe plan s we e g own up in a clima e oom unde s ic ly egula ed en i onmen al condi ions. Rela i e humidi y was main ained be ween 65- 75%, ligh /da k cycle was 16/8 h s wi h a espec i e 25/20°C empe a u e pe iodici y, and ligh in ensi y was kep in cons an 300 μmol m-2s-1 du ing day ime. Plan g ow h in nu ien solu ion The nu ien solu ion ha was used o plan g ow h had he ollowing composi ion: 2.0 mM Ca(NO3)2, 0.7 mM K2SO4, 0.5 mM MgSO4, 0.1 mM KH2PO4, 0.1 mM KCl, 10 µM H3BO3, 0.5 µM MnSO4, 0.5 µM ZnSO4 and 0.2 µM CuSO4. I on was supplied in he o m o 10-4 M Fe-EDTA, oo [20]. Selenium was supplemen ed o he nu ien solu ion as wo species o seleni e in o m o Na2SeO3 and selena e in o m o Na2SeO4 in i e di e en concen a ions as ollows: 0 (con ol), 0.1, 0.3, 0.9, and 3 mg L-1. Nu ien solu ion was changed e e y 3 days and e apo a ed wa e was eplenished egula ly. The expe imen ended 3 weeks a e plan ing when hi d lea o con ol ea men g ew comple ely and seedlings had app oxima ely 30-20 cm long shoo s and oo s, espec i ely. Expe imen s we e ca ied ou in iplica es ( h ee po s), whe e e e y po had ou seedlings. Chlo ophyll lo escence pa ame e s measu emen The Chlo ophyll luo escence was de e mined on da k- adap ed lea es (20 min o da k adap a ion) by a aching ligh exclusion clips o he cen al egion o each sun lowe lea , and he chlo ophyll luo escence pa ame e s we e measu ed by a po able chlo ophyll luo ome e -PAM-2100 (WALZ, Ge many). The luo escence pa ame e s eco ded include he minimal luo escence (Fo) when all PSII cen es a e open (open s a e) and inc eases wi h a maximum (Fm) when PSII cen es a e closed (closed s a e), he a iable luo escence (F ), he po en ial pho osyn he ic capaci y (F /Fo) which e lec s he e iciency o elec on dona ion o PSII and he a io (Fm–Fo)/Fm ha also known as F /Fm which is calcula ed om luo escence alues Fo and Fm. The F /Fm a io is one o he mos common pa ame e s used in luo escence ha e lec s he capaci y o ap elec on by he PSII eac ion cen e. In his s udy all o he luo escence pa ame e s, including Fo, F , Fm, F /Fm and F /Fo o olde and younge sun lowe lea es we e de e mined. Pho osyn he ic pa ame e s measu emen The pho osyn he ic a e was de e mined using a Cl-340 handheld pho osyn hesis sys em (ClD Company, Camas, USA). The sys em was ope a ed unde open sys em measu emen and ligh a achmen (PAR-1200). The ne pho osyn hesis a es (Pn) and anspi a ion a e (E) o olde and younge sun lowe lea es we e de e mined. S a is ical analyses All da a we e s a is ically analyzed using SPSS 17.0 so wa e, and he mean alues o each ea men g oup we e subjec ed o mul iple compa isons analysis using he One-Way ANOVA and a signi icance le el o p < 0.05. The ba s indica e he s anda d e o o he mean. Signi ican di e ences in he mean alue o each ea men g oup a e indica ed by di e en lowe case le e s based on he LSD es (p < 0.05, n = 3) when he da a we e homogenous and Games-Howell es (p < 0.05, n = 3) when he da a we e no homogenous. Resul s and Discussion SeIV up ake e ec s on chlo ophyll lo escence pa ame e s o sun lowe ’s old and young lea es Figu e 1 displays Fo, F and Fm alues a di e en concen a ions o SeIV ha was no seen any signi ican di e ence be ween hese chlo ophyll lo escence pa ame e s. Figu e 2 displays (F /Fm) and (F /Fo) alues a di e en concen a ions o SeIV ha was no seen any signi ican di e ence be ween hese chlo ophyll lo escence pa ame e s. SeVI up ake e ec s on chlo ophyll lo escence pa ame e s o sun lowe ’s old and young lea es Figu e 3 displays Fo, F and Fm alues a di e en concen a ions o SeVI. Abou Fo he e is no signi ican di e ence bu con ol in bo h F and Fm has he mos amoun and diminish p ocess in 0.9 and 3 SeVI mg L-1 is ob ious. Figu e 4 displays (F /Fm) and (F /Fo) alues a di e en concen a ions o SeVI. 0.3 mg L-1 SeVI and 0.1 mg L-1 in bo h F /Fm and F /Fo has he mos amoun in old and young lea es espec i ely and diminish p ocess in 0.9 and 3 mg L-1 SeVI is ob ious. SeIV up ake e ec s on Pho osyn he ic pa ame e s o sun lowe ’s old and young lea es Figu e 5 displays Pn and E alues a di e en concen a ions o SeIV. 0.1 mg L-1 SeIV in bo h Pn and E has he mos amoun s and diminish p ocess in 0.9 and 3 mg L-1 SeIV is ob ious. Figu e 6 displays Pn and E alues a di e en concen a ions o SeIV. 0.3 mg L-1 SeIV in Pn and 0.1 mg L-1 SeIV in E has he mos amoun and diminish p ocess in 0.9 and 3 mg L-1 SeIV is ob ious. SeVI up ake e ec s on Pho osyn he ic pa ame e s o sun lowe ’s old and young lea es Figu e 7 displays Pn and E alues a di e en concen a ions o SeVI. 0.3 mg L-1 SeIV in Pn and 0.1 mg L-1 SeIV in E has he mos amoun and diminish p ocess in 0.9 and 3 mg L-1 SeIV is ob ious. In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium 3/8 Copy igh : ©2016 Ga ousi e al. Ci a ion: Ga ousi F, Ko ács B, Ve es S (2016) In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium. Ad Plan s Ag ic Res 3(1): 00083. DOI: 10.15406/apa .2016.03.00083 Figu e 1: SeIV up ake e ec s on he minimal luo escence (Fo), a iable luo escence (F ) and maximal luo escence (Fm) o sun lowe ’s old and young lea es. The ba s indica e he s anda d e o o he mean based on LSD es (p < 0.05, n = 3). Figu e 2: SeIV up ake e ec s on (F /Fm) and po en ial pho osyn he ic capaci y (F /Fo) o sun lowe ’s old and young lea es. The ba s indica e he s anda d e o o he mean based on LSD es (p < 0.05, n = 3). Figu e 8 displays Pn and E alues a di e en concen a ions o SeVI. 0.1 mg L-1 SeIV in Pn and 0.3 mg L-1 SeIV in E has he mos amoun and diminish p ocess in 0.9 and 3 mg L-1 SeIV is ob ious. Conce ning Fo, al hough he e is no signi ican di e ence wi h inc easing he applica ion o di e en le el o selena e, F and Fm had he opposi e end. Con ol samples in bo h F and Fm ha e he highes alues compa ing wi h he 0.9 and 3 mg L-1 SeVI samples, which ha e lowe and lowes alues, espec i ely. In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium 4/8 Copy igh : ©2016 Ga ousi e al. Ci a ion: Ga ousi F, Ko ács B, Ve es S (2016) In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium. Ad Plan s Ag ic Res 3(1): 00083. DOI: 10.15406/apa .2016.03.00083 Figu e 3: SeVI up ake e ec s on he minimal luo escence (Fo), a iable luo escence (F ) and maximal luo escence (Fm) o sun lowe ’s old and young lea es. The ba s indica e he s anda d e o o he mean. Signi ican di e ences in he mean alue o each ea men g oup a e indica ed by di e en lowe case le e based on LSD es (p < 0.05, n = 3). Figu e 4: SeVI up ake e ec s on (F /Fm) and po en ial pho osyn he ic capaci y (F /Fo) o sun lowe ’s old and young lea es. The ba s indica e he s anda d e o o he mean. Signi ican di e ences in he mean alue o each ea men g oup a e indica ed by di e en lowe case le e based on Games-Howell es (p < 0.05, n = 3). As he concen a ion o applied Se u he inc eased om 0.9 o 3 mg L–1 SeVI, bo h he F /Fm and F /Fo a ios, Pn and E ended o dec ease. These cu en esul s indica e despi e he educ ions in he e iciency o he PSII pho ochemis y (F /Fm) in SeVI ea men s, his a io did no changed signi ican ly in all SeIV ea men s. These di e ences show ha sun lowe is able o be e main ain i s PSII ac i i y e en a he high le el o SeIV. In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium 5/8 Copy igh : ©2016 Ga ousi e al. Ci a ion: Ga ousi F, Ko ács B, Ve es S (2016) In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium. Ad Plan s Ag ic Res 3(1): 00083. DOI: 10.15406/apa .2016.03.00083 Figu e 5: SeIV up ake e ec s on pho osyn hesis a e (Pn) and anspi a ion a e (E) o sun lowe ’s old lea es. The ba s indica e he s anda d e o o he mean. Signi ican di e ences in he mean alue o each ea men g oup a e indica ed by di e en lowe case le e based on Games-Howell es (p < 0.05, n = 3). Figu e 6: SeIV up ake e ec s on pho osyn hesis a e (Pn) and anspi a ion a e (E) o sun lowe ’s young lea es. The ba s indica e he s anda d e o o he mean. Signi ican di e ences in he mean alue o each ea men g oup a e indica ed by di e en lowe case le e based on LSD es (p < 0.05, n = 3). In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium 6/8 Copy igh : ©2016 Ga ousi e al. Ci a ion: Ga ousi F, Ko ács B, Ve es S (2016) In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium. Ad Plan s Ag ic Res 3(1): 00083. DOI: 10.15406/apa .2016.03.00083 Figu e 7: SeIV up ake e ec s on pho osyn hesis a e (Pn) and anspi a ion a e (E) o sun lowe ’s old lea es. The ba s indica e he s anda d e o o he mean. Signi ican di e ences in he mean alue o each ea men g oup a e indica ed by di e en lowe case le e based on Games-Howell es (p < 0.05, n = 3). Figu e 8: SeVI up ake e ec s on pho osyn hesis a e (Pn) and anspi a ion a e (E) o sun lowe ’s young lea es. The ba s indica e he s anda d e o o he mean. Signi ican di e ences in he mean alue o each ea men g oup a e indica ed by di e en lowe case le e based on LSD es (p < 0.05, n = 3). In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium 7/8 Copy igh : ©2016 Ga ousi e al. Ci a ion: Ga ousi F, Ko ács B, Ve es S (2016) In es iga ion o Pho osyn hesis S a us o Sun lowe Plan s Up- aking Di e en Fo ms o Selenium. Ad Plan s Ag ic Res 3(1): 00083. DOI: 10.15406/apa .2016.03.00083 Valkama e al. [21] sugges ed ha he high selena e dosage had a ha m ul e ec on pho osyn hesis ia changes in ac i i y and/ o biosyn hesis o enzymes, a he han ia al e a ion o PSII. In a ield expe imen , i is epo ed ha , applied Se as seleni e a concen a ions anged om 20 o 50 g Se ha-1 enhanced pho osyn hesis a e and he ac i i y o he pho osyn he ic sys em in ice plan s [22]. Ne e heless, as he concen a ion o seleni e inc eased > 50 g Se ha-1, bo h he F /Fm and F /Fo a ios ended o dec ease. Some s udies ocused on he enhanced e ec o Se on di e en pa ame e s o chlo ophyll luo escence unde di e en s esses including UV-B adia ion in s awbe y [21], unde cadmium s ess in ape seedlings [23] as well as unde high empe a u e s ess so ghum [24]. Conclusion P oducing Se-en iched c ops is iewed as nu i ionally signi ican o Se-de icien egions o he wo ld whe e die s we e epo ed o ha e insu icien amoun s o Se [25-28], due in pa o inadequa e Se in ood c ops [26, 28]. The p esen ed esul s allow us o conclude ha he e ec s o Se in amoun o 0.1 and 0.3 mg L-1 SeVI on sun lowe plan s ha we e g own in nu ien solu ion cul u es p o ide he bes esul s in almos all chlo ophyll luo escence (F /Fm and F /Fo) and pho osyn he ic (Pn and E) appa a us in bo h old and young lea es, hen app op ia e applica ion o Se can p o ec he pho osyn he ic sys em om inju y whe eas u he concen a ion o Se in bo h o ms o SeIV and SeVI (> 0.3 mg L-1) has e e se abo e e ec s. Finally, he ac i i y o he pho osyn he ic sys em in sun lowe is closely associa ed wi h he applica ion o Se, and he app op ia e Se con en in he plan s migh p omp pho osyn hesis, causing o inc eased p oduc ion and he pho osyn hesis o chlo ophyll luo escence pa ame e s can be applied o de e mine he Se s a us o p oduc ion o Se- ich sun lowe . Re e ences 1. El ashidi MA, Ad iano DC, Wo kman SM, Lindsay WL (1987) Chemical equilib ia o selenium in soils: a heo e ical de elopmen . Soil Science 144(2): 141˗152. 2. 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