Izilawuli zokukhula kwezitshalo zisetshenziswe njengesu lokunciphisa ukucindezeleka kokushisa ezitshalweni ezihlukahlukene

Ukukhiqizwa kwelayisi kuyehla ngenxa yokushintsha kwesimo sezulu nokuhlukahluka eColombia.Izilawuli zokukhula kwezitshalozisetshenziswe njengesu lokunciphisa ukucindezeleka kokushisa ezitshalweni ezihlukahlukene. Ngakho-ke, inhloso yalolu cwaningo kwakuwukuhlola imiphumela yomzimba (i-stomatal conductance, stomatal conduct, total chlorophyll content, Fv/Fm ratio of two commercial rice genotypes ngaphansi kwengcindezi yokushisa ehlanganisiwe (izinga lokushisa eliphezulu emini nasebusuku), izinga lokushisa le-canopy kanye nokuqukethwe kwamanzi okuhlobene) nokuguquguquka kwe-biochemical (malondialdehyde (okuqukethwe kwe-MDA) kanye ne-prolinic acid). Ukuhlolwa kokuqala nokwesibili kwenziwa kusetshenziswa izitshalo zezinhlobo ezimbili zerayisi i-Federrose 67 (“F67”) ne-Federrose 2000 (“F2000”), ngokulandelana. Kokubili ukuhlolwa kwahlaziywa ndawonye njengochungechunge lwezivivinyo. Izindlela zokwelapha ezimisiwe zazimi kanje: ukulawulwa okuphelele (AC) (izitshalo zelayisi ezitshalwe emazingeni okushisa afanele (ukushisa kwemini/ubusuku 30/25°C)), ukulawulwa kokucindezeleka kokushisa (SC) [izitshalo zelayisi zingaphansi kwengcindezi yokushisa ehlangene kuphela (40/25°C). 30°C)], nezitshalo zelayisi zacindezelwa futhi zafuthwa ngezilawuli zokukhula kwezitshalo (ukucindezeleka+AUX, ukucindezeleka+BR, ukucindezeleka+CK noma ukucindezeleka+GA) kabili (izinsuku ezingu-5 ngaphambi nangezinsuku ezingu-5 ngemva kokucindezeleka kokushisa). Ukufafaza nge-SA kunyuse isamba sokuqukethwe kwe-chlorophyll yazo zombili izinhlobo (isisindo esisha sezitshalo zelayisi “F67″ kanye “F2000″ sasingu-3.25 no-3.65 mg/g, ngokulandelana) uma kuqhathaniswa nezitshalo ze-SC (isisindo esisha se-“F67″ sasingu-2.36 kanye no-2.56 mg). ngokuvamile ithuthukise ukuqhutshwa kwesisu kwerayisi “F2000″ izitshalo (499.25 vs. 150.60 mmol m-2 s) uma kuqhathaniswa nokulawula ukucindezeleka kokushisa. ukucindezeleka kokushisa, izinga lokushisa lomqhele wezitshalo liyancipha ngo-2-3 °C, futhi okuqukethwe kwe-MDA ezitshalweni kuncipha. Inkomba yokubekezelela okuhlobene ibonisa ukuthi ukusetshenziswa kwe-foliar kwe-CK (97.69%) kanye ne-BR (60.73%) kungasiza ekudambiseni inkinga yokushisa okuhlanganisiwe. ukucindezeleka ikakhulukazi ezitshalweni zerayisi ze-F2000. Sengiphetha, ukufafaza nge-foliar kwe-BR noma i-CK kungabhekwa njengesu le-agronomic ukusiza ukunciphisa imiphumela emibi yezimo ezihlanganisiwe zokucindezeleka kokushisa ekuziphatheni komzimba kwezitshalo zelayisi.
Ilayisi (i-Oryza sativa) ingeyomndeni wakwaPoaceae futhi ingenye yezinhlamvu ezitshalwa kakhulu emhlabeni kanye nommbila nokolweni (Bajaj kanye noMohanty, 2005). Indawo engaphansi kokulinywa kwerayisi ingamahektha angu-617,934, kanti ukukhiqizwa kukazwelonke ngo-2020 kwakungamathani angu-2,937,840 ngesivuno esimaphakathi esingu-5.02 tons/ha (Federarroz (Federación Nacional de Arroceros), 2021).
Ukufudumala kwembulunga yonke kuthinta izitshalo zelayisi, okuholela ezinhlotsheni ezihlukahlukene zengcindezi ye-abiotic njengamazinga okushisa aphezulu kanye nezikhathi zesomiso. Ukushintsha kwesimo sezulu kubangela amazinga okushisa embulunga yonke enyuke; Amazinga okushisa kulindeleke ukuthi akhuphuke ngo-1.0–3.7°C ekhulwini lama-21, okungase kwandise ukuvama nokuqina kwengcindezi yokushisa . Ukwenyuka kwamazinga okushisa emvelo kuye kwaphazamisa irayisi, okwenza isivuno sezitshalo sehle ngo-6-7%. Ngakolunye uhlangothi, ukushintsha kwesimo sezulu nakho kuholela ezimweni ezingezinhle zemvelo ezitshalweni, njengezikhathi zesomiso esibi noma amazinga okushisa aphezulu ezindaweni ezishisayo nezishisayo . Ngaphezu kwalokho, izehlakalo zokuguquguquka ezifana ne-El Niño zingaholela ekucindezelekeni kokushisa futhi zandise ukulimala kwezitshalo kwezinye izindawo ezishisayo. E-Colombia, amazinga okushisa ezindaweni ezikhiqiza irayisi kulindeleke ukuthi akhuphuke ngo-2-2.5°C ngo-2050, anciphise ukukhiqizwa kwerayisi futhi athinte ukugeleza komkhiqizo ezimakethe kanye namaketanga okuhlinzeka.
Izilimo eziningi zelayisi zitshalwa ezindaweni lapho amazinga okushisa eseduze nebanga elifanele lokukhula kwezitshalo (Shah et al., 2011). Kubikwe ukuthi isilinganiso esiphezulu samazinga okushisa emini nasebusukuukukhula nokuthuthukiswa kwerayisingokuvamile kungu-28°C no-22°C, ngokulandelanayo (Kilasi et al., 2018; Calderón-Páez et al., 2021). Amazinga okushisa angaphezu kwalezi zisekelo angabangela izinkathi zengcindezi yokushisa emaphakathi noma eqinile phakathi nezigaba ezibucayi zokukhula kwerayisi (i-tillering, i-anthesis, ukuqhakaza, nokugcwaliswa okusanhlamvu), ngaleyo ndlela kuthinte kabi isivuno sokusanhlamvu . Lokhu kuncipha kwesivuno kubangelwa ikakhulukazi isikhathi eside sokucindezeleka kokushisa, okuthinta i-physiology yezitshalo . Ngenxa yokusebenzelana kwezinto ezihlukahlukene, njengobude besikhathi sokucindezeleka nezinga lokushisa eliphakeme elifinyelelwe, ingcindezi yokushisa ingabangela uhla lomonakalo ongenakulungiseka kumetabolism nentuthuko yezitshalo .
Ukucindezeleka kokushisa kuthinta izinqubo ezihlukahlukene ze-physiological and biochemical ezitshalweni. I-photosynthesis yamaqabunga ingenye yezinqubo ezingenwa kalula yingcindezi yokushisa ezitshalweni zelayisi, njengoba izinga le-photosynthesis lehla ngo-50% lapho izinga lokushisa lansuku zonke lidlula ku-35°C. Izimpendulo ze-physiological zezitshalo zelayisi ziyahlukahluka kuye ngohlobo lokucindezeleka kokushisa. Isibonelo, amazinga e-photosynthetic kanye ne-stomatal conductance ayavinjelwa lapho izitshalo zichayeka emazingeni okushisa aphezulu emini (33-40°C) noma izinga lokushisa eliphezulu emini nasebusuku (35–40°C emini, 28–30°C). C kusho ubusuku) (Lü et al., 2013; Fahad et al., 2016; Chaturvedi et al., 2017). Amazinga okushisa aphezulu ebusuku (30°C) abangela ukuvinjelwa okumaphakathi kwe-photosynthesis kodwa andise ukuphefumula ebusuku (Fahad et al., 2016; Alvarado-Sanabria et al., 2017). Kungakhathaliseki ukuthi yisiphi isikhathi sokucindezeleka, ukucindezeleka kokushisa kuphinde kuthinte okuqukethwe kwe-chlorophyll yeqabunga, isilinganiso se-chlorophyll variable fluorescence to maximum chlorophyll fluorescence (Fv/Fm), kanye nokusebenza kwe-Rubisco ezitshalweni zelayisi (Cao et al. 2009; Yin et al. 2010). ) USanchez Reynoso et al., 2014).
Izinguquko ze-biochemical zingesinye isici sokujwayela kwezitshalo ekucindezelekeni kokushisa (Wahid et al., 2007). Okuqukethwe kwe-proline kusetshenziswe njengenkomba ye-biochemical yokucindezeleka kwezitshalo (Ahmed and Hassan 2011). I-Proline idlala indima ebalulekile ekusetshenzisweni kwezitshalo njengoba isebenza njengomthombo wekhabhoni noma we-nitrogen nanjenge-membrane stabilizer ngaphansi kwezimo zokushisa eziphezulu (Sánchez-Reinoso et al., 2014). Amazinga okushisa aphezulu aphinde athinte ukuzinza kwe-membrane ngokusebenzisa i-lipid peroxidation, okuholela ekwakhekeni kwe-malondialdehyde (MDA) (Wahid et al., 2007). Ngakho-ke, okuqukethwe kwe-MDA kuye kwasetshenziselwa ukuqonda ubuqotho besakhiwo se-membrane yamaseli ngaphansi kokucindezeleka kokushisa (Cao et al., 2009; Chavez-Arias et al., 2018). Ekugcineni, ukucindezeleka kokushisa okuhlanganisiwe [37/30 ° C (usuku/ubusuku)] kwenyusa iphesenti lokuvuza kwe-electrolyte kanye nokuqukethwe kwe-malondialdehyde elayisi (Liu et al., 2013).
Ukusetshenziswa kwezilawuli zokukhula kwezitshalo (GRs) kuhlolwe ukunciphisa imiphumela emibi yokucindezeleka kokushisa, njengoba lezi zinto zibandakanyeka ngenkuthalo ekuphenduleni kwezitshalo noma izindlela zokuvikela umzimba ngokumelene nokucindezeleka okunjalo (Peleg noBlumwald, 2011; Yin et al. et al., 2011; Ahmed et al., 2015). Ukusetshenziswa kwangaphandle kwemithombo yofuzo kube nomthelela omuhle ekubekezeleleni ukucindezeleka kokushisa ezitshalweni ezihlukahlukene. Ucwaningo luye lwabonisa ukuthi ama-phytohormones afana ne-gibberellins (GA), i-cytokinins (CK), i-auxins (AUX) noma i-brassinosteroids (BR) iholela ekwandeni kweziguquguquko ezihlukahlukene ze-physiological and biochemical (Peleg no-Blumwald, 2011; Yin et al. Ren, 2011; Mitler, 2011; 2014). E-Colombia, ukusetshenziswa kwangaphandle kwemithombo yofuzo kanye nomthelela wako ezitshalweni zelayisi akuzange kuqondwe futhi kufundwe ngokugcwele. Kodwa-ke, ucwaningo lwangaphambilini lubonise ukuthi ukufafaza kwe-foliar kwe-BR kungathuthukisa ukubekezelelana kwelayisi ngokuthuthukisa izici zokushintshaniswa kwegesi, i-chlorophyll noma okuqukethwe kwe-proline yamaqabunga ezithombo zelayisi (Quintero-Calderón et al., 2021).
Ama-Cytokinins aqondisa izimpendulo zezitshalo ekucindezelekeni kwe-abiotic, kufaka phakathi ukucindezeleka kokushisa (Ha et al., 2012). Ngaphezu kwalokho, kuye kwabikwa ukuthi ukusetshenziswa kwangaphandle kwe-CK kunganciphisa umonakalo oshisayo. Isibonelo, ukusetshenziswa kwangaphandle kwe-zeatin kukhuphule izinga le-photosynthetic, okuqukethwe kwe-chlorophyll a no-b, kanye nokusebenza kahle kokuthutha kwe-electron ku-creeping bentgrass (Agrotis estolonifera) phakathi nengcindezi yokushisa (Xu and Huang, 2009; Jespersen and Huang, 2015). Ukusetshenziswa kwangaphandle kwe-zeatin kungabuye kuthuthukise umsebenzi we-antioxidant, kuthuthukise ukuhlanganiswa kwamaprotheni ahlukahlukene, kunciphise ukulimala kwezinhlobo ze-oxygen esebenzayo (ROS) kanye nokukhiqizwa kwe-malondialdehyde (MDA) ezicutshini zezitshalo (Chernyadyev, 2009; Yang et al., 2009). , 2016; Kumar et al., 2020).
Ukusetshenziswa kwe-gibberellic acid kuye kwabonisa impendulo enhle ekucindezelekeni kokushisa. Ucwaningo luye lwabonisa ukuthi i-GA biosynthesis ixhumanisa izindlela ezihlukahlukene ze-metabolic futhi yandisa ukubekezelelana ngaphansi kwezimo zokushisa eziphezulu (u-Alonso-Ramirez et al. 2009; Khan et al. 2020). U-Abdel-Nabi et al. (2020) bathole ukuthi ukufuthwa kwe-foliar kwe-GA yangaphandle (25 noma 50 mg*L) kungakhuphula izinga le-photosynthetic kanye nomsebenzi wokulwa ne-antioxidant ezitshalweni eziwolintshi ezinengcindezi yokushisa uma kuqhathaniswa nezitshalo zokulawula. Kuphinde kwaqashelwa ukuthi ukusetshenziswa kwangaphandle kwe-HA kukhulisa umswakama ohlobene, i-chlorophyll nokuqukethwe kwe-carotenoid futhi kunciphisa i-lipid peroxidation ku-date palm (Phoenix dactylifera) ngaphansi kwengcindezi yokushisa (Khan et al., 2020). I-Auxin nayo idlala indima ebalulekile ekulawuleni izimpendulo zokukhula eziguquguqukayo ezimweni zokushisa okuphezulu (Sun et al., 2012; Wang et al., 2016). Lesi silawuli sokukhula sisebenza njengomaka we-biochemical ezinqubweni ezihlukahlukene ezifana ne-proline synthesis noma ukuwohloka ngaphansi kwengcindezi ye-abiotic (Ali et al. 2007). Ngaphezu kwalokho, i-AUX iphinde ithuthukise umsebenzi we-antioxidant, okuholela ekwehleni kwe-MDA ezitshalweni ngenxa yokuncipha kwe-lipid peroxidation (Bielach et al., 2017). USergeev nabanye. (2018) ibone ukuthi ezitshalweni ze-pea (i-Pisum sativum) ngaphansi kwengcindezi yokushisa, okuqukethwe kwe-proline - dimethylaminoethoxycarbonylmethyl)naphthylchloromethyl ether (TA-14) kuyanda. Ocwaningweni olufanayo, baphinde babona amazinga aphansi e-MDA ezitshalweni ezilashwayo uma kuqhathaniswa nezitshalo ezingaphathwanga nge-AUX.
I-Brassinosteroids ingelinye ikilasi lezilawuli zokukhula ezisetshenziselwa ukunciphisa imiphumela yokucindezeleka kokushisa. Ogweno et al. (2008) ibike ukuthi i-exogenous BR spray inyuse izinga le-photosynthetic enetha, i-stomatal conductance kanye nesilinganiso esiphezulu se-Rubisco carboxylation of tomato (Solanum lycopersicum) izitshalo ngaphansi kwengcindezi yokushisa izinsuku ezingu-8. Ukufafaza nge-Foliar kwe-epibrassinosteroids kungakhuphula izinga le-photosynthetic yezitshalo zekhukhamba (Cucumis sativus) ngaphansi kwengcindezi yokushisa (Yu et al., 2004). Ngaphezu kwalokho, ukusetshenziswa kwangaphandle kwe-BR kubambezela ukuwohloka kwe-chlorophyll futhi kukhulisa ukusebenza kahle kokusetshenziswa kwamanzi kanye nesivuno esiphezulu se-PSII photochemistry ezitshalweni ezingaphansi kwengcindezi yokushisa (Holá et al., 2010; Toussagunpanit et al., 2015).
Ngenxa yokushintsha kwesimo sezulu nokuhlukahluka, izitshalo zelayisi zibhekana nezikhathi zamazinga okushisa aphezulu nsuku zonke (Lesk et al., 2016; Garcés, 2020; Federarroz (Federación Nacional de Arroceros), 2021). Ku-phenotyping yezitshalo, ukusetshenziswa kwe-phytonutrients noma ama-biostimulants kuye kwafundwa njengesu lokunciphisa ukucindezeleka kokushisa ezindaweni ezitshala irayisi (Alvarado-Sanabria et al., 2017; Calderón-Páez et al., 2021; Quintero-Calderón et al., 2021). Ukwengeza, ukusetshenziswa kwezinto eziguquguqukayo ze-biochemical kanye ne-physiological (izinga lokushisa leqabunga, i-stomatal conductance, imingcele ye-chlorophyll fluorescence, i-chlorophyll kanye nokuqukethwe kwamanzi okuhlobene, i-malondialdehyde kanye ne-proline synthesis) iyithuluzi elithembekile lokuhlola izitshalo zelayisi ngaphansi kwengcindezi yokushisa endaweni nakwamanye amazwe (Sánchez -Reynoso et al., Al. 2017; Kodwa-ke, ucwaningo mayelana nokusetshenziswa kwezifutho ze-phytohormonal elayisi ezingeni lendawo lihlala liyivelakancane. ipharamitha ye-chlorophyll fluorescence kanye nokuqukethwe kwamanzi okuhlobene) kanye nemiphumela ye-biochemical yokusetshenziswa kwe-foliar kwezilawuli ezine zokukhula kwezitshalo (AUX, CK, GA kanye ne-BR). (Ama-photosynthetic pigments, malondialdehyde kanye ne-proline content) Okuguquguqukayo kuma-genotypes amabili erayisi elithengiswayo angaphansi kwengcindezi yokushisa ehlangene (amazinga okushisa aphezulu emini/ubusuku).
Kulolu cwaningo, kwenziwa ukuhlola okubili okuzimele. I-genotypes Federrose 67 (F67: i-genotype eyakhiwe emazingeni aphezulu okushisa phakathi neminyaka eyishumi edlule) kanye ne-Federrose 2000 (F2000: i-genotype eyakhiwe eminyakeni eyishumi yokugcina yekhulu lama-20 ebonisa ukumelana negciwane leqabunga elimhlophe) zasetshenziswa okokuqala ngqa. imbewu. kanye nokuhlolwa kwesibili, ngokulandelana. Zombili izinhlobo ze-genotype zilinywa kabanzi abalimi baseColombia. Imbewu ihlwanyelwe kumathreyi angu-10-L (ubude obungu-39.6 cm, ububanzi obuyi-28.8 cm, ukuphakama bungu-16.8 cm) equkethe inhlabathi eyisihlabathi somhlabathi eno-2% wezinto eziphilayo. Imbewu emihlanu engakamili yatshalwa ethreyini ngayinye. Amaphalethi abekwe endaweni ebamba ukushisa ye-Faculty of Agricultural Sciences of the National University of Colombia, campus Bogotá (43°50′56″ N, 74°04′051″ W), endaweni ephakeme ngamamitha angu-2556 ngaphezu kwezinga lolwandle (asl). m.) futhi zenziwa kusukela ngo-Okthoba kuya kuDisemba 2019. Ukuhlolwa okukodwa (Federroz 67) nokuhlolwa kwesibili (Federroz 2000) ngesizini efanayo ka-2020.
Izimo zemvelo ku-greenhouse phakathi nenkathi yokutshala ngayinye zimi kanje: izinga lokushisa lobusuku nemini 30/25°C, umswakama ohlobene 60~80%, isikhathi sesithombe semvelo amahora angu-12 (i-photosynthetically active radiation 1500 µmol (photons) m-2 s-). 1 emini). Izitshalo zavundiswa ngokuvumelana nokuqukethwe kwesici ngasinye ezinsukwini ezingu-20 ngemva kokuvela kwembewu (DAE), ngokusho kukaSánchez-Reinoso et al. (2019): 670 mg nitrogen isitshalo ngasinye, 110 mg phosphorus isitshalo ngasinye, 350 mg potassium isitshalo ngasinye, 68 mg calcium isitshalo ngasinye, 20 mg magnesium isitshalo ngasinye, 20 mg isulfure isitshalo ngasinye, 17 mg i-silicon isitshalo ngasinye. Izitshalo ziqukethe 10 mg boron isitshalo ngasinye, 17 mg yethusi isitshalo ngasinye, kanye 44 mg zinc isitshalo ngasinye. Izitshalo zelayisi zagcinwa kuze kufike ku-47 DAE ekuhloleni ngakunye lapho zifinyelela esigabeni se-phenological V5 ngalesi sikhathi. Ucwaningo lwangaphambili lubonise ukuthi lesi sigaba se-phenological yisikhathi esifanele sokuqhuba izifundo zokucindezeleka kokushisa elayisi (Sánchez-Reinoso et al., 2014; Alvarado-Sanabria et al., 2017).
Esivivinyweni ngasinye, izicelo ezimbili ezihlukene zokulawula ukukhula kwamaqabunga zenziwa. Isethi yokuqala yezifutho ze-foliar phytohormone yasetshenziswa ezinsukwini ezi-5 ngaphambi kokwelashwa kwengcindezi yokushisa (42 DAE) ukulungisa izitshalo ukuze zibhekane nokucindezeleka kwemvelo. Isifutho sesibili se-foliar sabe sesinikezwa ezinsukwini ezi-5 ngemuva kokuba izitshalo zichayeke ezimeni zokucindezeleka (52 DAE). Kwasetshenziswa ama-phytohoorrones amane kanti izakhiwo zesithako ngasinye esisebenzayo esifaywe kulolu cwaningo zibhalwe etafuleni elengeziwe 1 I-GA3); (iii) Cytokinin (trans-zeatin) 1 × 10-5 M (iv) Brassinosteroids [Spirostan-6-one, 3,5-dihydroxy-, (3b,5a,25R)] 5 × 10-5; M. Lokhu kugxila kukhethwe ngoba kuveza izimpendulo ezinhle futhi kwandise ukumelana kwezitshalo ekucindezelekeni kokushisa (Zahir et al., 2001; Wen et al., 2010; El-Bassiony et al., 2012; Salehifar et al., 2017). Izitshalo zelayisi ngaphandle kwezifutho zokulawula ukukhula kwezitshalo zaziphathwa ngamanzi acwecwe kuphela. Zonke izitshalo zelayisi zafuthwa ngesifutho sesandla. Gcoba u-20 ml H2O esitshalweni ukuze umanzise indawo engaphezulu nephansi yamaqabunga. Zonke izifutho ze-foliar zisebenzisa i-adjuvant yezolimo (i-Agrotin, i-Bayer CropScience, e-Colombia) ku-0.1% (v/v). Ibanga eliphakathi kwebhodwe ne-sprayer lingama-30 cm.
Ukwelashwa kwengcindezi yokushisa kwenziwa ezinsukwini ezi-5 ngemva kwesifutho sokuqala se-foliar (47 DAE) ekuhloleni ngakunye. Izitshalo zelayisi zidluliselwe ku-greenhouse zayiswa ekamelweni lokukhula elingu-294 L (MLR-351H, Sanyo, IL, USA) ukuze kusungulwe ingcindezi yokushisa noma kugcinwe izimo ezifanayo zemvelo (47 DAE). Ukwelashwa kokucindezeleka kokushisa okuhlanganisiwe kwenziwa ngokubeka ikamelo emazingeni okushisa alandelayo emini/ebusuku: izinga lokushisa eliphakeme emini [40°C amahora angu-5 (kusuka ngo-11:00 kuya ku-16:00)] nesikhathi sasebusuku [30°C amahora angu-5] . Izinsuku eziyi-8 zilandelana (kusuka ngo-19:00 kuye ku-24:00). Izinga lokushisa lokucindezeleka nesikhathi sokuchayeka zikhethwe ngokusekelwe ezifundweni zangaphambilini (u-Sánchez-Reynoso et al. 2014; Alvarado-Sanabría et al. 2017). Ngakolunye uhlangothi, iqoqo lezitshalo ezidluliselwe ekamelweni lokukhula laligcinwa ku-greenhouse ezingeni lokushisa elifanayo (30 ° C emini / 25 ° C ebusuku) izinsuku ezingu-8 ezilandelanayo.
Ekupheleni kokuhlolwa, amaqembu okwelapha alandelayo atholwe: (i) isimo sokushisa sokukhula + ukusetshenziswa kwamanzi acwengekile [Ukulawula okuphelele (AC)], (ii) isimo sokucindezeleka kokushisa + ukusetshenziswa kwamanzi acwebile [Ukulawula ukucindezeleka kokushisa (SC)], (iii) izimo zokucindezeleka kokushisa + isicelo se-auxin (AUX), (iv) isimo sokucindezeleka kokushisa + isicelo se-gibberellin (isimo sokushisa + se-vtoCK), (isimo sokucindezeleka sokushisa) (isimo sokushisa se-vtoCK) + I-brassinosteroid (BR) Isithasiselo. Lawa maqembu okwelapha asetshenziselwa izinhlobo ezimbili ze-genotypes (F67 kanye ne-F2000). Zonke izindlela zokwelapha zenziwa ngendlela engahleliwe ngokuphelele eneziphindaphinda ezinhlanu, ngayinye ihlanganisa isitshalo esisodwa. Isitshalo ngasinye sasetshenziselwa ukufunda okuguquguqukayo okunqunywe ekupheleni kokuhlolwa. Ukuhlolwa kuthathe i-55 DAE.
I-stomatal conductance (gs) ikalwe kusetshenziswa i-porosometer ephathekayo (SC-1, METER Group Inc., USA) esukela ku-0 ukuya ku-1000 mmol m-2 s-1, enesampula yokuvula igumbi elingu-6.35 mm. Izilinganiso zithathwa ngokunamathisela i-stomameter probe eqabungeni elivuthiwe futhi ihlumela eliyinhloko lesitshalo linwetshwe ngokugcwele. Ngokwelashwa ngakunye, ukufundwa kwe-gs kwathathwa emaqabunga amathathu esitshalo ngasinye phakathi kuka-11:00 no-16:00 futhi kwalinganiswa.
I-RWC yanqunywa ngokwendlela echazwe nguGhoulam et al. (2002). Ishidi elinwetshwe ngokugcwele elisetshenziselwa ukunquma u-g nalo lasetshenziswa ukukala i-RWC. Isisindo esisha (FW) sinqunywa ngokushesha ngemva kokuvuna kusetshenziswa isikali sedijithali. Amaqabunga abe esefakwa esitsheni sepulasitiki esigcwele amanzi futhi ashiywe ebumnyameni endaweni yokushisa yasekamelweni (22°C) amahora angu-48. Bese ukala esikalini sedijithali bese urekhoda isisindo esinwetshiwe (TW). Amaqabunga avuvukele omisiwe kuhhavini omisiwe ku-75°C amahora angu-48 futhi isisindo sawo esomile (DW) sarekhodwa.
Okuqukethwe kwe-chlorophyll okuhlobene kwanqunywa kusetshenziswa imitha ye-chlorophyll (atLeafmeter, FT Green LLC, USA) futhi kuvezwe ngamayunithi e-atLeaf (Dey et al., 2016). Ukufundwa kokusebenza kahle kwe-quantum kwe-PSII (isilinganiso se-Fv/Fm) kwarekhodwa kusetshenziswa i-chlorophyll fluorimeter evuselelayo eqhubekayo (I-PeA Handy, Hansatech Instruments, UK). Amaqabunga aye ashintshwa amnyama kusetshenziswa izinsimbi zamaqabunga imizuzu engu-20 ngaphambi kwezilinganiso ze-Fv/Fm (Restrepo-Diaz ne-Garces-Varon, 2013). Ngemuva kokuthi amaqabunga esenziwe amnyama, isisekelo (F0) kanye ne-fluorescence enkulu (Fm) kukalwa. Kusukela kule datha, i-fluorescence eguquguqukayo (Fv = Fm – F0), isilinganiso se-fluorescence eguquguqukayo ukuya ku-fluorescence enkulu (Fv/Fm), isivuno esiphezulu se-quantum se-PSII photochemistry (Fv/F0) kanye nesilinganiso Fm/F0 kubaliwe (Baker, 2008; Lee et al., 2017). Ukufundwa kwe-chlorophyll okuhlobene ne-chlorophyll fluorescence kuthathwe emaqabunga afanayo asetshenziselwa izilinganiso ze-gs.
Cishe ama-800 mg wesisindo esisha seqabunga aqoqwe njengokuguquguquka kwe-biochemical. Amasampula amaqabunga abe esehlanganiswa ku-nitrogen ewuketshezi futhi agcinwa ukuze ahlaziywe okwengeziwe. Indlela ye-spectrometric esetshenziselwa ukulinganisa izicubu ze-chlorophyll a, b kanye nokuqukethwe kwe-carotenoid isekelwe endleleni nezibalo ezichazwe ngu-Wellburn (1994). Amasampula ezicubu zeqabunga (30 mg) aqoqwa futhi ahlanganiswa ku-3 ml we-acetone engama-80%. Amasampula abe ese-centrifuged (imodeli 420101, Becton Dickinson Primary Care Diagnostics, USA) ngo-5000 rpm imizuzu eyi-10 ukuze kukhishwe izinhlayiya. I-supernatant yahlanjululwa yaba yivolumu yokugcina engu-6 ml ngokungeza i-acetone engu-80% (Sims and Gamon, 2002). Okuqukethwe kwe-chlorophyll kwanqunywa kokuthi 663 (chlorophyll a) kanye 646 (chlorophyll b) nm, kanye ne-carotenoids ku-470 nm kusetshenziswa i-spectrophotometer (Spectronic BioMate 3 UV-vis, Thermo, USA).
Indlela ye-thiobarbituric acid (TBA) echazwe nguHodges et al. (1999) yasetshenziselwa ukuhlola i-membrane lipid peroxidation (MDA). Cishe i-0.3 g yezicubu zeqabunga nayo yahlanganiswa ku-nitrogen ewuketshezi. Amasampula abe yi-centrifuged ku-5000 rpm futhi ukumunca kukalwa nge-spectrophotometer ku-440, 532 kanye no-600 nm. Ekugcineni, ukugxila kwe-MDA kubalwe kusetshenziswa i-extinction coefficient (157 M mL−1).
Okuqukethwe kwe-proline kukho konke ukwelashwa kwanqunywa kusetshenziswa indlela echazwe ngu-Bates et al. (1973). Engeza u-10 ml wesisombululo esinamanzi esingu-3% se-sulfosalicylic acid kwisampula egciniwe bese uhlunga ngephepha lokuhlunga i-Whatman (No. 2). Khona-ke u-2 ml wale filtrate wasabela ngo-2 ml we-ninhydric acid no-2 ml we-glacial acetic acid. Ingxube ifakwe kubhavu wamanzi ku-90 ° C ihora elingu-1. Misa ukusabela ngokufukamela eqhweni. Nyakazisa ithubhu ngamandla usebenzisa i-vortex shaker bese uhlakaza isisombululo esiwumphumela ku-4 ml we-toluene. Ukufundwa kwe-Absorbance kwanqunywa ku-520 nm kusetshenziswa i-spectrophotometer efanayo esetshenziselwa ukulinganisa izibala ze-photosynthetic (Spectronic BioMate 3 UV-Vis, Thermo, Madison, WI, USA).
Indlela echazwe nguGerhards et al. (2016) ukubala izinga lokushisa le-canopy ne-CSI. Izithombe ezishisayo zithathwe ngekhamera ye-FLIR 2 (FLIR Systems Inc., Boston, MA, USA) ngokunemba okungu-±2°C ekupheleni kwesikhathi sokucindezeleka. Beka indawo emhlophe ngemuva kwesitshalo ukuze uthwebule izithombe. Futhi, izimboni ezimbili zazibhekwa njengamamodeli okubhekisela. Izitshalo zazibekwe endaweni emhlophe; enye yayimbozwe nge-adjuvant yezolimo (i-Agrotin, i-Bayer CropScience, i-Bogotá, i-Colombia) ukuze ilingise ukuvulwa kwakho konke i-stomata [imodi emanzi (i-Twet)], kanti enye kwakuyiqabunga elingenazo noma yiluphi uhlelo lokusebenza [Imodi eyomile (Tdry)] (Castro -Duque et al., 2020). Ibanga phakathi kwekhamera nebhodwe ngesikhathi sokuqoshwa laliyimitha elingu-1.
Inkomba yokubekezelelana okuhlobene ibalwa ngokungaqondile kusetshenziswa i-stomatal conductance (gs) yezitshalo eziphathwayo uma kuqhathaniswa nezitshalo zokulawula (izitshalo ezingenazo zokwelapha ukucindezeleka kanye nezilawuli zokukhula ezisetshenzisiwe) ukuze kunqunywe ukubekezelelana kwe-genotypes ephathwayo ehlolwe kulolu cwaningo. I-RTI yatholwa kusetshenziswa i-equation ethathelwe ku-Chávez-Arias et al. (2020).
Esivivinyweni ngasinye, zonke izinto eziguquguqukayo zomzimba okukhulunywe ngazo ngenhla zanqunywa futhi zarekhodwa ku-55 DAE kusetshenziswa amaqabunga anwetshwe ngokugcwele aqoqwe ku-canopy engenhla. Ngaphezu kwalokho, izilinganiso zenziwa ekamelweni lokukhula ukuze kugwenywe ukushintsha izimo zemvelo lapho izitshalo zikhula khona.
Idatha evela ekuhlolweni kokuqala nokwesibili yahlaziywa ndawonye njengochungechunge lwezivivinyo. Iqembu ngalinye lokuhlola laliqukethe izitshalo ezi-5, futhi isitshalo ngasinye sakha iyunithi yokuhlola. Ukuhlaziywa kokuhluka (ANOVA) kwenziwa (P ≤ 0.05). Lapho kutholwa umehluko omkhulu, ukuhlolwa kokuqhathanisa okuthunyelwe kuka-Tukey kwasetshenziswa ku-P ≤ 0.05. Sebenzisa umsebenzi we-arcsine ukuze uguqule amanani amaphesenti. Idatha yahlaziywa kusetshenziswa isofthiwe ye-Statistix v 9.0 (I-Analytical Software, Tallahassee, FL, USA) futhi yahlelwa kusetshenziswa i-SigmaPlot (inguqulo 10.0; I-Systat Software, San Jose, CA, USA). Ukuhlaziywa kwengxenye eyinhloko kwenziwa kusetshenziswa isofthiwe ye-InfoStat 2016 (I-Analysis Software, i-National University of Cordoba, e-Argentina) ukuze kuhlonzwe izilawuli ezingcono kakhulu zokukhula kwezitshalo ezisacwaningwayo.
Ithebula 1 lifingqa i-ANOVA ebonisa ukuhlola, izindlela zokwelapha ezihlukene, nokusebenzisana kwazo nama-photosynthetic pigments amaqabunga (i-chlorophyll a, b, ingqikithi, ne-carotenoids), i-malondialdehyde (MDA) nokuqukethwe kwe-proline, kanye nokuqhutshwa kwesisu. Umthelela we-gs, okuqukethwe kwamanzi okuhlobene. (RWC), okuqukethwe kwe-chlorophyll, imingcele ye-chlorophyll alpha fluorescence, izinga lokushisa lomqhele (PCT) (°C), inkomba yokucindezeleka kwezitshalo (CSI) kanye nenkomba yokubekezelela okuhlobene yezitshalo zelayisi ku-55 DAE.
Ithebula 1. Isifinyezo sedatha ye-ANOVA eguquguqukayo yerayisi ye-physiological kanye ne-biochemical phakathi kokuhlolwa (ama-genotype) nokwelashwa kwengcindezi yokushisa.
Umehluko (P≤0.01) ekusebenzelaneni kwe-photosynthetic pigment yeqabunga, okuqukethwe kwe-chlorophyll okuhlobene (ukufundwa kwe-Atleaf), kanye nemingcele ye-alpha-chlorophyll fluorescence phakathi kokuhlolwa nokwelashwa kuboniswa kuThebula 2. Amazinga okushisa aphezulu emini nasebusuku andise ingqikithi ye-chlorophyll nokuqukethwe kwe-carotenoid. Izithombo zelayisi ezingenaso isifutho se-foliar se-phytohormones (2.36 mg g-1 for “F67″ kanye no-2.56 mg g-1 for “F2000″) uma kuqhathaniswa nezitshalo ezitshalwe ngaphansi kwezimo zokushisa ezisezingeni eliphezulu (2.67 mg g -1)) zibonise okuqukethwe kwe-chlorophyll ephansi. Kuzo zombili izivivinyo, i-“F67” yayingu-2.80 mg g-1 futhi “F2000” yayingu-2.80 mg g-1. Ngaphezu kwalokho, izithombo zelayisi eziphathwe ngenhlanganisela yezifutho ze-AUX ne-GA ngaphansi kwengcindezi yokushisa nazo zibonise ukwehla kokuqukethwe kwe-chlorophyll kuzo zombili izinhlobo ze-genotype (AUX = 1.96 mg g-1 kanye ne-GA = 1.45 mg g-1 ye-“F67”; 2.24 mg) g-1 kanye ne-GA = 1.43 mg g-1 (ye-“F2000″ ) ngaphansi kwezimo zengcindezi yokushisa. Ngaphansi kwezimo zengcindezi yokushisa, ukwelashwa kwe-foliar nge-BR kuphumele ekwenyukeni okuncane kulokhu kuhlukahluka kuzo zombili izinhlobo ze-genotype. Ekugcineni, isifutho se-CK foliar sabonisa amanani aphezulu kakhulu e-photosynthetic pigment phakathi kwazo zonke izindlela zokwelapha (i-AUX, GA, BR, SC kanye nokwelashwa kwe-AC) kuma-genotypes F67 (3.24 mg g-1) kanye ne-F2000 (3.65 mg g-1). Okuqukethwe okuhlobene kwe-chlorophyll (iyunithi ye-Atleaf) nakho kwehliswa ukucindezela kokushisa okuhlangene. Amanani aphakeme kakhulu nawo aqoshwa ezitshalweni ezifuthwe nge-CC kuzo zombili izinhlobo ze-genotype (41.66 ye-“F67” kanye ne-49.30 ye-“F2000”). Izilinganiso ze-Fv ne-Fv/Fm zibonise umehluko omkhulu phakathi kwemithi yokwelapha nezimila (Ithebula 2). Sekukonke, phakathi kwalokhu okuguquguqukayo, i-cultivar F67 yayingenwa kalula yingcindezi yokushisa kune-cultivar F2000. Izilinganiso ze-Fv ne-Fv/Fm zihlupheke kakhulu esivivinyweni sesibili. Izithombo ezingu-'F2000′ ezigcizelelwe ezingafuthwanga nganoma yimaphi ama-phytohormones zazinamanani aphansi e-Fv (2120.15) kanye nezilinganiso ze-Fv/Fm (0.59), kodwa ukufutha nge-foliar nge-CK kusize ukubuyisela lawa manani (Fv: 2591, 89, Fv/Fm3 ratio). , ithola ukufundwa okufana nalokhu okurekhodwe ezitshalweni ze-“F2000” ezitshalwe ngaphansi kwezimo ezilungile zokushisa (Fv: 2955.35, Fv/Fm ratio: 0.73:0.72). Bekungekho mehluko obalulekile ku-fluorescence yokuqala (F0), i-fluorescence ephezulu (Fm), isivuno esiphezulu se-photochemical quantum se-PSII (Fv/F0) nesilinganiso se-Fm/F0. Ekugcineni, i-BR ibonise ukuthambekela okufanayo njengoba kuphawulwe nge-CK (Fv 2545.06, Fv/Fm ratio 0.73).
Ithebula 2. Umthelela wengcindezi yokushisa ehlanganisiwe (40°/30°C imini/ubusuku) ku-photosynthetic pigments yamaqabunga [ingqikithi ye-chlorophyll (Chl Total), i-chlorophyll a (Chl a), i-chlorophyll b (Chl b) kanye nomphumela we-carotenoids Cx+c] ], iyunithi ye-chlorophyll ehlobene), iyunithi ye-chlorophyllophyll (iyunithi ye-reminiophyll) i-fluorescence (F0), i-fluorescence ephezulu (Fm), i-fluorescence eguquguqukayo (Fv), ukusebenza kahle okuphezulu kwe-PSII (Fv/Fm), isivuno se-photochemical quantum esiphezulu se-PSII (Fv/F0 ) kanye ne-Fm/F0 ezitshalweni zezinhlobo ezimbili zerayisi [Federrose 67 (F67) kanye ne-Federrose 00 ngemva kwezinsuku ezingu-50 eziphuma ku-20 (DAE)).
Okuqukethwe kwamanzi okuhlobene (i-RWC) yezitshalo zelayisi eziphathwe ngendlela ehlukile kubonise umehluko (P ≤ 0.05) ekusebenzelaneni phakathi kokuhlolwa nokwelashwa kwe-foliar (Fig. 1A). Lapho iphathwa nge-SA, amanani aphansi kakhulu aqoshwa kuzo zombili izinhlobo ze-genotypes (74.01% ku-F67 kanye no-76.6% ku-F2000). Ngaphansi kwezimo zengcindezi yokushisa, i-RWC yezitshalo zelayisi yazo zombili izinhlobo ze-genotype eziphathwa ngama-phytohormones ahlukene yanda kakhulu. Sekukonke, ukusetshenziswa kwe-foliar ye-CK, GA, AUX, noma i-BR kwenyusa i-RWC ukuze ibe amanani afanayo nalawo ezitshalo ezitshalwe ngaphansi kwezimo ezifanele ngesikhathi sokuhlolwa. Ukulawula okuphelele kanye nezitshalo ezifuthwe ngama-foliar ziqophe amanani acishe abe ngu-83% kuwo womabili ama-genotypes. Ngakolunye uhlangothi, i-gs iphinde yabonisa umehluko omkhulu (P ≤ 0.01) ekusebenzisaneni kokuhlolwa kokwelashwa (Fig. 1B). Isitshalo se-absolute control (AC) siphinde saqopha amanani aphakeme kakhulu ku-genotype ngayinye (440.65 mmol m-2s-1 ku-F67 kanye no-511.02 mmol m-2s-1 ku-F2000). Izitshalo zelayisi ezingaphansi kwengcindezi yokushisa ehlanganisiwe zizodwa zibonise amanani aphansi we-gs kuzo zombili izinhlobo ze-genotypes (150.60 mmol m-2s-1 ku-F67 kanye no-171.32 mmol m-2s-1 ku-F2000). Ukwelashwa ngamahlamvu nazo zonke izilawuli zokukhula kwezitshalo nakho kwanda g. Ezitshalweni zerayisi ze-F2000 ezifuthwe nge-CC, umphumela wokufafaza kwe-foliar nge-phytohormones wawusobala kakhulu. Leli qembu lezitshalo alikhombisanga mehluko uma kuqhathaniswa nezitshalo zokulawula ngokuphelele (AC 511.02 kanye ne-CC 499.25 mmol m-2s-1).
Umfanekiso 1. Umthelela wengcindezi yokushisa ehlanganisiwe (40°/30°C imini/ubusuku) kokuqukethwe kwamanzi okuhlobene (RWC) (A), i-stomatal conductance (gs) (B), ukukhiqizwa kwe-malondialdehyde (MDA) (C), nokuqukethwe kwe-proline . (D) ezitshalweni ze-rice genotypes (F67 kanye ne-F2000) ezinsukwini ezingama-55 ngemuva kokuvela (DAE). Ukwelashwa okuhlolelwe i-genotype ngayinye kuhlanganisa: ukulawula okuphelele (AC), ukulawula ukucindezeleka kokushisa (SC), ukucindezeleka kokushisa + auxin (AUX), ukucindezeleka kokushisa + i-gibberellin (GA), ukucindezeleka kokushisa + i-cell mitogen (CK), nokucindezeleka kokushisa + brassinosteroid. (BR). Ikholomu ngayinye imelela isilinganiso ± iphutha elivamile lamaphoyinti amahlanu edatha (n = 5). Amakholomu alandelwa izinhlamvu ezihlukene abonisa umehluko obalulekile ngokwezibalo ngokuya ngokuhlolwa kuka-Tukey (P ≤ 0.05). Izinhlamvu ezinophawu olulinganayo zibonisa ukuthi incazelo ayibalulekile ngokwezibalo (≤ 0.05).
I-MDA (P ≤ 0.01) kanye ne-proline (P ≤ 0.01) okuqukethwe nakho kubonise umehluko omkhulu ekusebenzisaneni phakathi kokuhlolwa nokwelashwa kwe-phytohormone (Fig. 1C, D). Ukwenyuka kwe-lipid peroxidation kwabonwa ngokwelashwa kwe-SC kuzo zombili izinhlobo ze-genotype (Umfanekiso 1C), nokho izitshalo eziphathwe ngesifutho sokulawula ukukhula kwamaqabunga zibonise ukwehla kwe-lipid peroxidation kuzo zombili izinhlobo ze-genotype; Ngokuvamile, ukusetshenziswa kwe-phytohormones (CA, AUC, BR noma GA) kuholela ekwehleni kwe-lipid peroxidation (okuqukethwe kwe-MDA). Awukho umehluko otholakele phakathi kwezitshalo ze-AC zama-genotypes amabili nezitshalo ngaphansi kwengcindezi yokushisa futhi zafafazwa ngama-phytohormones (amanani e-FW aqashelwe ezitshalweni ze-“F67” asukela ku-4.38–6.77 µmol g-1, nasezitshalweni ze-FW “F2000” “amanani agciniwe asuka ku-9.18 g kuya ku-18 g kwesinye isitshalo). ngesandla, i-proline synthesis ku-"F67" yezitshalo yayiphansi kunezitshalo "ze-F2000" ngaphansi kwengcindezi ehlangene, okuholele ekwandeni kokukhiqizwa kwe-proline ezitshalweni zerayisi ezicindezelwe ukushisa, kuzo zombili izivivinyo, kwaphawulwa ukuthi ukulawulwa kwala mahomoni kwandisa kakhulu okuqukethwe kwe-amino acid yezitshalo ze-F2000 (AUX kanye ne-BR44 g-30) ngokuhlonipha. (Umdwebo 1G).
Imiphumela yesilawuli sokulawula ukukhula kwesitshalo se-foliar kanye nokucindezeleka kokushisa okuhlanganisiwe ekushiseni kwe-canopy yezitshalo kanye ne-related tolerance index (RTI) kukhonjiswe ku-Figure 2A kanye no-B. Kuzo zombili izinhlobo ze-genotype, izinga lokushisa le-canopy lezitshalo ze-AC lalisondele ku-27°C, kanti lezezitshalo ze-SC lalilinganiselwa ku-28°C. NGE. Kuphinde kwaqashelwa ukuthi ukwelapha ngamahlamvu nge-CK kanye ne-BR kuholele ekwehleni ngo-2–3°C kwezinga lokushisa le-canopy uma kuqhathaniswa nezitshalo ze-SC (Umfanekiso 2A). I-RTI ibonise ukuziphatha okufanayo kwezinye izinto eziguquguqukayo zomzimba, okubonisa umehluko omkhulu (P ≤ 0.01) ekusebenzisaneni phakathi kokuhlolwa nokwelashwa (Umfanekiso we-2B). Izitshalo ze-SC zibonise ukubekezelelana okuphansi kwezitshalo kuzo zombili izinhlobo ze-genotypes (34.18% kanye no-33.52% wezitshalo zelayisi "F67" kanye "F2000", ngokulandelana). Ukondla ngama-foliar kwama-phytohormones kuthuthukisa i-RTI ezitshalweni ezivezwe ekucindezelekeni okuphezulu kwamazinga okushisa. Lo mphumela ugqame kakhulu ezitshalweni ze-“F2000” ezifuthwe nge-CC, lapho i-RTI yayingu-97.69. Ngakolunye uhlangothi, umehluko ophawulekayo wabonwa kuphela kunkomba yokucindezeleka kwesivuno (CSI) yezitshalo zelayisi ngaphansi kwezimo zokucindezeleka ze-foliar factor spray (P ≤ 0.01) (Fig. 2B). Izitshalo zelayisi kuphela ezingaphansi kwengcindezi yokushisa eyinkimbinkimbi zabonisa inani eliphakeme kakhulu lenkomba yengcindezi (0.816). Lapho izitshalo zelayisi zifuthwa ngama-phytohormones ahlukahlukene, inkomba yokucindezeleka yayiphansi (amanani asuka ku-0.6 kuya ku-0.67). Ekugcineni, isitshalo serayisi esikhule ngaphansi kwezimo ezifanele sasinenani lika-0.138.
Umfanekiso 2. Imiphumela yengcindezi yokushisa ehlanganisiwe (40°/30°C imini/ubusuku) ekushiseni kwe-canopy (A), inkomba yokubekezelelana kwesihlobo (RTI) (B), kanye nenkomba yokucindezeleka kwezitshalo (CSI) (C) yezinhlobo ezimbili zezitshalo. I-genotype yerayisi yezohwebo (i-F67 ne-F2000) yabhekana nokwelashwa okuhlukile kokushisa. Ukwelashwa okuhlolelwe i-genotype ngayinye kuhlanganisa: ukulawula okuphelele (AC), ukulawula ukucindezeleka kokushisa (SC), ukucindezeleka kokushisa + auxin (AUX), ukucindezeleka kokushisa + i-gibberellin (GA), ukucindezeleka kokushisa + i-cell mitogen (CK), nokucindezeleka kokushisa + brassinosteroid. (BR). Ingcindezi yokushisa ehlanganisiwe ihlanganisa ukubeka izitshalo zelayisi emazingeni okushisa aphezulu emini/ebusuku (40°/30°C imini/ubusuku). Ikholomu ngayinye imelela isilinganiso ± iphutha elivamile lamaphoyinti amahlanu edatha (n = 5). Amakholomu alandelwa izinhlamvu ezihlukene abonisa umehluko obalulekile ngokwezibalo ngokuya ngokuhlolwa kuka-Tukey (P ≤ 0.05). Izinhlamvu ezinophawu olulinganayo zibonisa ukuthi incazelo ayibalulekile ngokwezibalo (≤ 0.05).
Ukuhlaziywa kwengxenye eyinhloko (i-PCA) yembula ukuthi iziguquko ezihlolwe ku-55 DAE zichaze i-66.1% yezimpendulo ze-physiological kanye ne-biochemical yezitshalo zelayisi ezicindezelwe ukushisa eziphathwe nge-spray yokulawula ukukhula (Fig. 3). Ama-Vectors amelela okuguquguqukayo futhi amachashazi amelela izilawuli zokukhula kwezitshalo (GRs). Ama-vectors we-gs, okuqukethwe kwe-chlorophyll, ukusebenza kahle kwe-quantum okuphezulu kwe-PSII (Fv/Fm) kanye nemingcele ye-biochemical (TChl, MDA kanye ne-proline) kuma-engeli aseduze nomsuka, okubonisa ukuhlobana okuphezulu phakathi kokuziphatha kokuphila kwezitshalo nazo. eguquguqukayo. Iqembu elilodwa (V) lalihlanganisa izithombo zelayisi ezitshalwe ezingeni lokushisa elifanele (AT) kanye nezitshalo ezingu-F2000 eziphathwe nge-CK ne-BA. Ngesikhathi esifanayo, izitshalo eziningi eziphathwe nge-GR zakha iqembu elihlukile (IV), futhi ukwelashwa nge-GA ku-F2000 kwakha iqembu elihlukile (II). Ngokuphambene, izithombo zelayisi ezigcizelelwe ngokushisa (amaqembu I kanye no-III) ngaphandle kwanoma yisiphi isifutho se-foliar se-phytohormones (zombili izinhlobo ze-genotype zaziyi-SC) zazibekwe endaweni ephambene neqembu V, okubonisa umphumela wokucindezeleka kokushisa ku-physiology yezitshalo. .
Umfanekiso 3. Ukuhlaziywa kwe-bigraphical yemiphumela yokucindezeleka kokushisa okuhlanganisiwe (40 ° / 30 ° C imini/ubusuku) ezitshalweni zezinhlobo ezimbili ze-rice genotypes (F67 kanye ne-F2000) ezinsukwini ezingu-55 ngemva kokuvela (DAE). Izifinyezo: AC F67, ukulawula okuphelele F67; I-SC F67, ukulawula ukucindezeleka kokushisa F67; I-AUX F67, ukucindezeleka kokushisa + auxin F67; GA F67, ukucindezeleka ukushisa + gibberellin F67; I-CK F67, ukucindezeleka kokushisa + ukuhlukaniswa kweseli BR F67, ukucindezeleka kokushisa + i-brassinosteroid. F67; I-AC F2000, ukulawula okuphelele kwe-F2000; I-SC F2000, Ukulawula Ukucindezeleka Kokushisa F2000; I-AUX F2000, ingcindezi yokushisa + auxin F2000; I-GA F2000, ukucindezeleka kokushisa + gibberellin F2000; I-CK F2000, ukucindezeleka kokushisa + i-cytokinin, i-BR F2000, ukucindezeleka kokushisa + i-steroid yethusi; F2000.
Okuguquguqukayo okufana nokuqukethwe kwe-chlorophyll, ukuziphatha kwe-stomatal, isilinganiso se-Fv/Fm, i-CSI, i-MDA, i-RTI nokuqukethwe kwe-proline kungasiza ukuqonda ukulungiswa kwezinhlobo zelayisi ze-genotypes nokuhlola umthelela wamasu we-agronomic ngaphansi kwengcindezi yokushisa (Sarsu et al., 2018; Quintero-Calderon et al., 2021). Inhloso yalokhu kuhlolwa kwakuwukuhlola umphumela wokusetshenziswa kwezilawuli ezine zokukhula emikhawulweni yokuphila kanye ne-biochemical yezithombo zelayisi ngaphansi kwezimo eziyinkimbinkimbi zokucindezela ukushisa. Ukuhlolwa kwezithombo kuyindlela elula nesheshayo yokuhlola ngesikhathi esisodwa izitshalo zelayisi kuye ngobukhulu noma isimo sengqalasizinda etholakalayo (Sarsu et al. 2018). Imiphumela yalolu cwaningo ibonise ukuthi ukucindezeleka kokushisa okuhlangene kubangela izimpendulo ezihlukene zomzimba kanye ne-biochemical kuma-genotypes amabili elayisi, okubonisa inqubo yokuzivumelanisa. Le miphumela iphinda ikhombise ukuthi izifutho zokulawula ukukhula kwe-foliar (ikakhulukazi ama-cytokinins nama-brassinosteroids) zisiza irayisi ukuthi livumelane nengcindezi yokushisa eyinkimbinkimbi njengoba umusa uthinta kakhulu i-gs, i-RWC, isilinganiso se-Fv/Fm, izingulube ze-photosynthetic nokuqukethwe kwe-proline.
Ukusetshenziswa kwezilawuli zokukhula kusiza ukuthuthukisa isimo samanzi sezitshalo zelayisi ngaphansi kwengcindezi yokushisa, okungase kuhlotshaniswe nokucindezeleka okuphezulu kanye namazinga okushisa e-canopy ezitshalo aphansi. Lolu cwaningo lubonise ukuthi phakathi kwezitshalo ze-“F2000” (i-genotype esengozini), izitshalo zelayisi eziphathwe ngokuyinhloko nge-CK noma i-BR zazinamanani aphezulu we-gs kanye namanani aphansi e-PCT kunezitshalo eziphathwe nge-SC. Ucwaningo lwangaphambilini luphinde lwabonisa ukuthi i-gs ne-PCT ziyizinkomba ezinembile zomzimba ezinganquma impendulo eguquguqukayo yezitshalo zelayisi kanye nemiphumela yamasu e-agronomic ekucindezelekeni kokushisa (Restrepo-Diaz noGarces-Varon, 2013; Sarsu et al., 2018; Quintero). -Carr DeLong et al., 2021). I-Leaf CK noma i-BR ithuthukisa i-g ngaphansi kwengcindezi ngoba lawa ma-hormone ezitshalo angakhuthaza ukuvulwa kwesisu ngokusebenzisana kokwenziwa namanye ama-molecule abonisa izimpawu ezifana ne-ABA (umgqugquzeli wokuvalwa kwesisu ngaphansi kwengcindezi ye-abiotic) (Macková et al., 2013; Zhou et al., 2013). 2013). ). , 2014). Ukuvulwa kwe-stomatal kukhuthaza ukupholisa kwamaqabunga futhi kusiza ukunciphisa izinga lokushisa kwe-canopy (Sonjaroon et al., 2018; Quintero-Calderón et al., 2021). Ngenxa yalezi zizathu, izinga lokushisa le-canopy lezitshalo zelayisi ezifuthwe nge-CK noma i-BR lingase libe phansi ngaphansi kwengcindezi yokushisa ehlangene.
Ukucindezeleka kokushisa okuphezulu kunganciphisa okuqukethwe kwe-photosynthetic pigment emaqabunga (Chen et al., 2017; Ahammed et al., 2018). Kulolu cwaningo, lapho izitshalo zelayisi zingaphansi kwengcindezi yokushisa futhi zingafuthwanga nanoma yiziphi izilawuli zokukhula kwezitshalo, ama-photosynthetic pigments ayevame ukwehla kuzo zombili izinhlobo ze-genotype (Ithebula 2). Feng et al. (I-2013) iphinde yabika ukwehla okukhulu kokuqukethwe kwe-chlorophyll emaqabunga ama-genotype amabili kakolweni adalulwe ekucindezelekeni kokushisa. Ukuchayeka emazingeni okushisa aphakeme kuvame ukuholela ekwehleni kokuqukethwe kwe-chlorophyll, okungase kube ngenxa yokuncipha kwe-chlorophyll biosynthesis, ukuwohloka kwezingulube, noma imiphumela yazo ehlanganisiwe ngaphansi kwengcindezi yokushisa (Fahad et al., 2017). Kodwa-ke, izitshalo zelayisi eziphathwa kakhulu nge-CK kanye ne-BA zandise ukugxila kwemibala ye-photosynthetic yamaqabunga ngaphansi kwengcindezi yokushisa. Imiphumela efanayo iphinde yabikwa nguJespersen and Huang (2015) kanye no-Suchsagunpanit et al. (2015), obone ukwanda kokuqukethwe kwe-chlorophyll yeqabunga kulandela ukusetshenziswa kwe-zeatin namahomoni e-epibrassinosteroid ku-bentgrass egcizelelwe ukushisa nerayisi, ngokulandelana. Incazelo ezwakalayo yokuthi kungani i-CK kanye ne-BR bekhuthaza ukwanda kokuqukethwe kwe-chlorophyll yeqabunga ngaphansi kwengcindezi yokushisa ehlanganisiwe ukuthi i-CK ingase ithuthukise ukuqaliswa kokufakwa okuqhubekayo kwabathuthukisi benkulumo (abafana nomgqugquzeli ovuselela i-senescence-activating (SAG12) noma umgqugquzeli we-HSP18) futhi yehlise ukulahlekelwa kwe-chlorophyll emaqabunga. , ukubambezela ukukhula kweqabunga futhi kwandise ukumelana nezitshalo ekushiseni (Liu et al., 2020). I-BR ingavikela i-chlorophyll yeqabunga futhi ikhulise okuqukethwe kwe-chlorophyll yamaqabunga ngokwenza kusebenze noma ngokunxenxa ukuhlanganiswa kwama-enzyme abandakanyeka ku-chlorophyll biosynthesis ngaphansi kwezimo zokucindezeleka (Sharma et al., 2017; Siddiqui et al., 2018). Ekugcineni, ama-phytohormones amabili (CK kanye ne-BR) aphinde akhuthaze ukubonakaliswa kwamaprotheni okushisa ukushisa futhi athuthukise izinqubo ezihlukahlukene zokuzivumelanisa ne-metabolic, ezifana nokunyuka kwe-chlorophyll biosynthesis (Sharma et al., 2017; Liu et al., 2020).
I-Chlorophyll ipharamitha ye-fluorescence inikeza indlela esheshayo nengonakalisi engahlola ukubekezelelana kwezitshalo noma ukuzivumelanisa nezimo ze-abiotic stress (Chaerle et al. 2007; Kalaji et al. 2017). Amapharamitha afana nesilinganiso se-Fv/Fm asetshenziswe njengezinkomba zokujwayela kwezitshalo ezimweni zengcindezi (Alvarado-Sanabria et al. 2017; Chavez-Arias et al. 2020). Kulolu cwaningo, izitshalo ze-SC zibonise amanani aphansi kakhulu alokhu okuguquguqukayo, ikakhulukazi izitshalo zerayisi "F2000". Yin et al. (2010) iphinde yathola ukuthi isilinganiso se-Fv/Fm samaqabunga erayisi okuhlakula aphezulu sehle kakhulu emazingeni okushisa angaphezu kuka-35°C. Ngokusho kukaFeng et al. (2013), isilinganiso esiphansi se-Fv/Fm ngaphansi kokucindezeleka kokushisa sibonisa ukuthi izinga lokubanjwa kwamandla okuvusa amadlingozi nokuguqulwa yisikhungo sokusabela se-PSII sincishisiwe, okubonisa ukuthi isikhungo sokusabela se-PSII siyahlakazeka ngaphansi kwengcindezi yokushisa. Lokhu kubuka kusivumela ukuba siphethe ngokuthi ukuphazamiseka kumishini ye-photosynthetic kugqama kakhulu ezinhlobonhlobo ezibucayi (Fedearroz 2000) kunezinhlobo ezimelana (Fedearroz 67).
Ukusetshenziswa kwe-CK noma i-BR ngokuvamile kuthuthukisa ukusebenza kwe-PSII ngaphansi kwezimo eziyinkimbinkimbi zokucindezela ukushisa. Imiphumela efanayo yatholwa ngabakwa- Suchsagunpanit et al. (2015), owabona ukuthi isicelo se-BR sandise ukusebenza kahle kwe-PSII ngaphansi kwengcindezi yokushisa elayisi. Kumar et al. (2020) futhi bathole ukuthi izitshalo ze-chickpea ezilashwa nge-CK (6-benzyladenine) futhi ezingaphansi kwengcindezi yokushisa zandisa isilinganiso se-Fv/Fm, okuphetha ngokuthi ukusetshenziswa kwe-foliar kwe-CK ngokwenza kusebenze umjikelezo we-zeaxanthin pigment kukhuthaze umsebenzi we-PSII. Ukwengeza, isifutho seqabunga le-BR sasithanda i-PSII photosynthesis ngaphansi kwezimo zokucindezeleka ezihlangene, okubonisa ukuthi ukusetshenziswa kwale phytohormone kubangele ukuncipha kokuchithwa kwamandla okuvusa amadlingozi we-PSII antennae futhi kwakhuthaza ukuqoqwa kwamaprotheni okushisa amancane kuma-chloroplast (Ogweno et al. 2008; i-Kothari ne-Lachowitz). , 2021).
I-MDA kanye nokuqukethwe kwe-proline kuvame ukukhuphuka lapho izitshalo zingaphansi kwengcindezi ye-abiotic uma kuqhathaniswa nezitshalo ezitshalwe ngaphansi kwezimo ezifanele (Alvarado-Sanabria et al. 2017). Ucwaningo lwangaphambilini luphinde lwabonisa ukuthi amazinga e-MDA kanye ne-proline ayizinkomba ze-biochemical ezingasetshenziswa ukuqonda inqubo yokujwayela noma umthelela wezinqubo ze-agronomic elayisi ngaphansi kwamazinga okushisa aphezulu emini noma ebusuku (Alvarado-Sanabria et al., 2017; Quintero-Calderón et al. . , 2021). Lezi zifundo ziphinde zabonisa ukuthi i-MDA kanye nokuqukethwe kwe-proline kuvame ukuba phezulu ezitshalweni zelayisi ezivezwe emazingeni okushisa aphezulu ebusuku noma emini, ngokulandelana. Kodwa-ke, ukufuthwa ngamahlamvu e-CK kanye ne-BR kube nomthelela ekwehleni kwe-MDA kanye nokwenyuka kwamazinga e-proline, ikakhulukazi ku-genotype ebekezelayo (Federroz 67). I-CK spray ingakhuthaza ukuvezwa ngokweqile kwe-cytokinin oxidase/dehydrogenase, ngaleyo ndlela ikhulise okuqukethwe kwezinhlanganisela ezivikelayo ezifana ne-betaine ne-proline (Liu et al., 2020). I-BR ikhuthaza ukufakwa kwama-osmoprotectants afana ne-betaine, ushukela, nama-amino acids (okuhlanganisa i-proline yamahhala), ukugcina ibhalansi ye-osmotic yeselula ngaphansi kwezimo eziningi ezimbi zemvelo (Kothari noLachowiec, 2021).
Inkomba yokucindezeleka kwezitshalo (CSI) kanye nenkomba yokubekezelelana okuhlobene (RTI) isetshenziselwa ukunquma ukuthi ingabe izindlela zokwelapha ezihlolwayo zisiza ukunciphisa izingcindezi (abiotic ne-biotic) futhi zibe nomthelela omuhle kusayensi yokwakheka kwezitshalo (Castro-Duque et al., 2020; Chavez-Arias et al., 2020). Amanani e-CSI angasukela ku-0 kuye ku-1, amele izimo ezingezona ingcindezi nengcindezi, ngokulandelana (Lee et al., 2010). Amanani e-CSI ezitshalo ezicindezelwe ukushisa (SC) asukela ku-0.8 kuye ku-0.9 (Umfanekiso 2B), okubonisa ukuthi izitshalo zelayisi zathinteka kabi ngenxa yengcindezi ehlanganisiwe. Kodwa-ke, ukufuthwa kwe-foliar kwe-BC (0.6) noma i-CK (0.6) ikakhulukazi kuholele ekwehleni kwalesi sikhombi ngaphansi kwezimo zengcindezi ye-abiotic uma kuqhathaniswa nezitshalo zerayisi ze-SC. Ezitshalweni ze-F2000, i-RTI ibonise ukwanda okuphezulu lapho isebenzisa i-CA (97.69%) kanye ne-BC (60.73%) uma kuqhathaniswa ne-SA (33.52%), okubonisa ukuthi lezi zilawuli zokukhula kwezitshalo nazo zifaka isandla ekuthuthukiseni impendulo yerayisi ekubekezeleleni kokubunjwa. Ukushisa ngokweqile. Lezi indices ziye zahlongozwa ukuphatha izimo zokucindezeleka ezinhlotsheni ezahlukene. Ucwaningo olwenziwe ngu-Lee et al. (2010) ibonise ukuthi i-CSI yezinhlobo ezimbili zikakotini ngaphansi kwengcindezi yamanzi emaphakathi yayicishe ibe ngu-0.85, kanti amanani e-CSI ezinhlobonhlobo eziniselwe kahle asukela ku-0.4 kuye ku-0.6, ephetha ngokuthi le nkomba iyinkomba yokujwayela kwamanzi ezinhlobonhlobo. izimo ezicindezelayo. Ngaphezu kwalokho, u-Chavez-Arias et al. (2020) ihlole ukusebenza kwama-elicitors okwenziwa njengesu elibanzi lokulawula ingcindezi ezitshalweni ze-C. elegans futhi yathola ukuthi izitshalo ezifuthwe ngalezi zinhlanganisela zibonisa i-RTI ephezulu (65%). Ngokusekelwe kulokhu okungenhla, i-CK kanye ne-BR ingabhekwa njengamasu e-agronomic ahloselwe ukwandisa ukubekezelela irayisi ekucindezelekeni kokushisa okuyinkimbinkimbi, njengoba lezi zilawuli zokukhula kwezitshalo zenza izimpendulo ezinhle ze-biochemical nezokuphila.
Eminyakeni embalwa edlule, ucwaningo lwerayisi e-Colombia lugxile ekuhloleni ama-genotypes abekezelela amazinga okushisa aphezulu emini noma ebusuku kusetshenziswa izici zomzimba noma ze-biochemical (Sánchez-Reinoso et al., 2014; Alvarado-Sanabria et al., 2021). Kodwa-ke, eminyakeni embalwa edlule, ukuhlaziywa kobuchwepheshe obusebenzayo, obunomnotho kanye nenzuzo kuye kwaba kubaluleke kakhulu ukuphakamisa ukuphathwa kwezitshalo okudidiyelwe ukuze kuthuthukiswe imiphumela yezikhathi eziyinkimbinkimbi zokucindezeleka kokushisa ezweni (Calderón-Páez et al., 2021; Quintero-Calderon et al., 2021) . Ngakho-ke, ukusabela komzimba kanye ne-biochemical yezitshalo zelayisi ekucindezelekeni kokushisa okuyinkimbinkimbi (u-40°C usuku/30°C ebusuku) okuphawulwe kulolu cwaningo kusikisela ukuthi ukufutha ngamahlamvu nge-CK noma i-BR kungase kube indlela efanelekile yokuphatha izitshalo ukuze kuncishiswe imiphumela emibi. Umthelela wezikhathi zengcindezi yokushisa emaphakathi. Lezi zindlela zokwelapha zithuthukise ukubekezelelana kwakho kokubili kwe-rice genotypes (i-CSI ephansi kanye ne-RTI ephezulu), okubonisa ukuthambekela okuvamile ekuphenduleni kwezitshalo zomzimba kanye ne-biochemical ngaphansi kwengcindezi yokushisa ehlangene. Impendulo eyinhloko yezitshalo zelayisi kwaba ukwehla kokuqukethwe kwe-GC, i-chlorophyll ephelele, i-chlorophyll α ne-β kanye ne-carotenoids. Ngaphezu kwalokho, izitshalo zihlushwa ukulimala kwe-PSII (ukuncipha kwamapharamitha we-chlorophyll fluorescence njenge-Fv/Fm ratio) kanye nokwanda kwe-lipid peroxidation. Ngakolunye uhlangothi, lapho irayisi iphathwa nge-CK ne-BR, le miphumela emibi yancishiswa futhi okuqukethwe kwe-proline kwanda (Fig. 4).
Umfanekiso 4. Imodeli yomqondo yemiphumela yokucindezeleka kokushisa okuhlanganisiwe kanye nesilawuli sokukhula kwesitshalo se-foliar fafaza ezitshalweni zelayisi. Imicibisholo ebomvu neluhlaza okwesibhakabhaka ibonisa imiphumela emibi noma emihle yokusebenzisana phakathi kwengcindezi yokushisa kanye nokusetshenziswa kwe-foliar kwe-BR (brassinosteroid) kanye ne-CK (cytokinin) ezimpendulweni ze-physiological and biochemical, ngokulandelanayo. gs: ukuqhutshwa kwesisu; Ingqikithi ye-Chl: ingqikithi yokuqukethwe kwe-chlorophyll; I-Chl α: okuqukethwe kwe-chlorophyll β; Cx+c: okuqukethwe kwe-carotenoid;
Kafushane, izimpendulo ze-physiological kanye ne-biochemical kulolu cwaningo zibonisa ukuthi izitshalo zerayisi ze-Fedearroz 2000 zithinteka kakhulu enkathini yokucindezeleka kokushisa okuyinkimbinkimbi kunezitshalo zerayisi ze-Fedearroz 67. Zonke izilawuli zokukhula ezihlolwe kulolu cwaningo (ama-auxins, ama-gibberellins, ama-cytokinins, noma ama-brassinosteroids) abonise izinga elithile lokunciphisa ukucindezeleka kokushisa okuhlanganisiwe. Kodwa-ke, i-cytokinin ne-brassinosteroids zenze ukujwayela okungcono kwezitshalo njengoba zombili izilawuli zokukhula kwezitshalo zenyusa okuqukethwe kwe-chlorophyll, imingcele ye-alpha-chlorophyll fluorescence, i-gs kanye ne-RWC uma kuqhathaniswa nezitshalo zelayisi ngaphandle kwanoma yisiphi isicelo, futhi yehlisa okuqukethwe kwe-MDA nezinga lokushisa le-canopy. Kafushane, siphetha ngokuthi ukusetshenziswa kwezilawuli zokukhula kwezitshalo (i-cytokinins ne-brassinosteroids) iyithuluzi eliwusizo ekulawuleni izimo zokucindezeleka ezitshalweni zelayisi ezibangelwa ukucindezeleka okukhulu kokushisa phakathi nezikhathi zokushisa okuphezulu.
Izinto zangempela ezethulwe ocwaningweni zifakwe ne-athikili, futhi eminye imibuzo ingaqondiswa kumbhali ohambisanayo.