Zowongolera kukula kwa mbewu zagwiritsidwa ntchito ngati njira yochepetsera kutentha kwa mbewu zosiyanasiyana

Kupanga mpunga kukuchepa chifukwa cha kusintha kwa nyengo komanso kusintha kwanyengo ku Colombia.Zowongolera kukula kwa zomeraakhala akugwiritsidwa ntchito ngati njira yochepetsera kutentha kwa mbewu zosiyanasiyana. Choncho, cholinga cha phunziroli chinali kufufuza zotsatira za thupi (machitidwe a stomatal, stomatal conductance, chlorophyll content, Fv / Fm chiŵerengero cha mitundu iwiri ya malonda a mpunga wa genotypes omwe amakhudzidwa ndi kutentha kwakukulu (kutentha kwa usana ndi usiku), kutentha kwa denga ndi madzi okhudzana ndi madzi) ndi mitundu yosiyanasiyana ya biochemical (malondialdehyde (MDA) ndi prolinic acid content). Kuyesera koyamba ndi kwachiwiri kunachitika pogwiritsa ntchito mbewu zamitundu iwiri ya mpunga Federrose 67 ("F67") ndi Federrose 2000 ("F2000"), motsatana. Mayesero onse awiriwa adawunikidwa pamodzi ngati mayesero angapo. The anakhazikitsa mankhwala anali motere: kulamulira mtheradi (AC) (zomera mpunga wokula pa kutentha mulingo woyenera kwambiri (masana/usiku kutentha 30/25 ° C)), kutentha kupanikizika (SC) [zomera mpunga pansi kuphatikiza kutentha kupanikizika kokha (40/25°C). 30 ° C)], ndipo zomera za mpunga zinatsindikitsidwa ndi kupopera mankhwala oletsa kukula kwa zomera (kupanikizika + AUX, kupsinjika + BR, kupsinjika + CK kapena kupsinjika + GA) kawiri (masiku 5 isanafike ndi masiku 5 pambuyo pa kupsinjika kwa kutentha). Kupopera mbewu mankhwalawa ndi SA kunachulukitsa kuchuluka kwa chlorophyll m'mitundu yonse iwiri (kulemera kwatsopano kwa mbewu za mpunga "F67" ndi "F2000" kunali 3.25 ndi 3.65 mg/g, motsatana) poyerekeza ndi mbewu za SC (zolemera zatsopano za "F67" zinali 2.36 ndi 2.56 mg). zambiri bwino stomatal conductance mpunga "F2000" zomera (499.25 vs. 150.60 mmol m-2 s) poyerekeza ndi kutentha kulamulira nkhawa. kupsinjika kwa kutentha, kutentha kwa korona kumachepa ndi 2-3 ° C, ndipo zomwe zili mu MDA zimachepa. Chiwerengero cha kulekerera kwachibale chimasonyeza kuti kugwiritsa ntchito foliar kwa CK (97.69%) ndi BR (60.73%) kungathandize kuchepetsa vuto la kutentha pamodzi. nkhawa makamaka F2000 mpunga. Pomaliza, kupopera mbewu mankhwalawa kwa BR kapena CK kumatha kuonedwa ngati njira ya agronomic yothandizira kuchepetsa zovuta zomwe zimaphatikizidwa ndi kutentha kwapang'onopang'ono pamayendedwe achilengedwe a mbewu za mpunga.
Mpunga (Oryza sativa) ndi wa banja la Poaceae ndipo ndi imodzi mwa mbewu zomwe zimalimidwa kwambiri padziko lonse lapansi pamodzi ndi chimanga ndi tirigu (Bajaj ndi Mohanty, 2005). Dera lomwe amalima mpunga ndi mahekitala 617,934, ndipo kupanga dziko lonse mu 2020 kunali matani 2,937,840 ndi zokolola zapakati pa 5.02 matani / ha (Federarroz (Federación Nacional de Arroceros), 2021).
Kutentha kwapadziko lonse kumakhudza mbewu za mpunga, zomwe zimapangitsa kuti pakhale zovuta zosiyanasiyana monga kutentha kwambiri komanso nthawi ya chilala. Kusintha kwa nyengo kukuchititsa kuti kutentha kwa dziko lonse kukwera; Kutentha kukuyembekezeka kukwera ndi 1.0-3.7 ° C m'zaka za zana la 21, zomwe zitha kukulitsa kuchulukana komanso kuchuluka kwa kupsinjika kwa kutentha. Kuwonjezeka kwa kutentha kwa chilengedwe kwakhudza mpunga, zomwe zachititsa kuti zokolola zichepe ndi 6-7%. Kumbali ina, kusintha kwa nyengo kumabweretsanso kuti pakhale mikhalidwe yoipa ya chilengedwe cha mbewu, monga nyengo ya chilala choopsa kapena kutentha kwambiri m’madera otentha ndi otentha . Kuphatikiza apo, zochitika zosiyanasiyana monga El Niño zimatha kuyambitsa kupsinjika kwa kutentha ndikuwonjezera kuwonongeka kwa mbewu m'madera ena otentha. Ku Colombia, kutentha m'madera opangira mpunga kukuyembekezeka kuwonjezeka ndi 2-2.5 ° C pofika chaka cha 2050, kuchepetsa kupanga mpunga komanso kukhudza kutuluka kwa katundu kumisika ndi kugulitsa katundu.
Mbewu zambiri za mpunga zimabzalidwa m'madera momwe kutentha kuli pafupi ndi momwe mbewu zimakulira (Shah et al., 2011). Ananena kuti mulingo woyenera kwambiri pafupifupi usana ndi usiku kutentha kwakukula ndi chitukuko cha mpunganthawi zambiri amakhala 28 ° C ndi 22 ° C, motsatana (Kilasi et al., 2018; Calderón-Páez et al., 2021). Kutentha pamwamba pazigawozi kungayambitse nthawi ya kutentha kwapakati kapena koopsa panthawi yovuta kwambiri ya kukula kwa mpunga (kulima, kupatulira, kutulutsa maluwa, ndi kudzaza mbewu), motero kusokoneza zokolola. Izi kuchepetsa zokolola makamaka chifukwa cha nthawi yaitali kutentha kupsyinjika, zomwe zimakhudza zomera physiology . Chifukwa cha kuyanjana kwa zinthu zosiyanasiyana, monga kupsinjika kwanthawi yayitali komanso kutentha kwakukulu komwe kumafikira, kupsinjika kwa kutentha kumatha kubweretsa kuwonongeka kosasinthika kwa kagayidwe kazakudya ndi chitukuko.
Kupsyinjika kwa kutentha kumakhudza njira zosiyanasiyana za thupi ndi zamankhwala muzomera. Mitengo ya photosynthesis ya masamba ndi imodzi mwa njira zomwe zimakhudzidwa kwambiri ndi kutentha kwa zomera za mpunga, chifukwa chiwerengero cha photosynthesis chimachepa ndi 50% pamene kutentha kwa tsiku ndi tsiku kumaposa 35 ° C. Mayankho akuthupi a mbewu za mpunga amasiyana malinga ndi mtundu wa kupsinjika kwa kutentha. Mwachitsanzo, mitengo ya photosynthetic ndi stomatal conduction imalephereka pamene zomera zimatentha kwambiri masana (33-40 ° C) kapena kutentha kwa masana ndi usiku (35-40 ° C masana, 28-30 ° C). C amatanthauza usiku) (Lü et al., 2013; Fahad et al., 2016; Chaturvedi et al., 2017). Kutentha kwakukulu kwausiku (30 ° C) kumayambitsa kulepheretsa kwa photosynthesis koma kumawonjezera kupuma usiku (Fahad et al., 2016; Alvarado-Sanabria et al., 2017). Mosasamala kanthu za nthawi yopanikizika, kutentha kwa kutentha kumakhudzanso masamba a chlorophyll, chiwerengero cha chlorophyll variable fluorescence mpaka pazipita chlorophyll fluorescence (Fv / Fm), ndi Rubisco activation mu zomera mpunga (Cao et al. 2009; Yin et al. 2010). ) Sanchez Reynoso et al., 2014).
Kusintha kwa biochemical ndi gawo lina la kusintha kwa mbewu kupsinjika kwa kutentha (Wahid et al., 2007). Proline yakhala ikugwiritsidwa ntchito ngati chizindikiro cha biochemical cha kupsinjika kwa mbewu (Ahmed ndi Hassan 2011). Proline imagwira ntchito yofunika kwambiri pakupanga kagayidwe kazakudya chifukwa imakhala ngati gwero la kaboni kapena nitrogen komanso ngati membrane stabilizer pansi pa kutentha kwambiri (Sánchez-Reinoso et al., 2014). Kutentha kwakukulu kumakhudzanso kukhazikika kwa membrane kudzera mu lipid peroxidation, zomwe zimapangitsa kupanga malondialdehyde (MDA) (Wahid et al., 2007). Choncho, zolemba za MDA zakhala zikugwiritsidwanso ntchito kuti amvetse kukhulupirika kwapangidwe kwa ma membrane a selo pansi pa kutentha kwa kutentha (Cao et al., 2009; Chavez-Arias et al., 2018). Pomaliza, kupsinjika kwa kutentha kophatikizana [37/30 ° C (usana/usiku)] kunachulukitsa kuchuluka kwa kutulutsa kwa electrolyte ndi malondialdehyde mu mpunga (Liu et al., 2013).
Kugwiritsiridwa ntchito kwa olamulira a kukula kwa zomera (GRs) kwayesedwa kuti achepetse zotsatira zoipa za kupsinjika kwa kutentha, chifukwa zinthuzi zimagwira ntchito mwakhama pa mayankho a zomera kapena njira zotetezera thupi polimbana ndi nkhawa zotere (Peleg ndi Blumwald, 2011; Yin et al., 2011; Ahmed et al., 2015). Exogenous ntchito majini wakhala ndi zotsatira zabwino kutentha nkhawa kulolerana mu mbewu zosiyanasiyana. Kafukufuku wasonyeza kuti ma phytohormones monga gibberellins (GA), cytokinins (CK), auxins (AUX) kapena brassinosteroids (BR) amachititsa kuwonjezeka kwa mitundu yosiyanasiyana ya thupi ndi biochemical (Peleg ndi Blumwald, 2011; Yin et al. Ren, 2011; Mitler, Zhout et al. 2014). Ku Colombia, kugwiritsa ntchito ma genetic komanso momwe zimakhudzira mbewu za mpunga sikunamveke bwino ndikuphunziridwa. Komabe, kafukufuku wam'mbuyomu adawonetsa kuti kupopera mbewu mankhwalawa kwa BR kumatha kupititsa patsogolo kulekerera kwa mpunga mwa kukonza mawonekedwe a kusinthana kwa mpweya, chlorophyll kapena proline zomwe zili mumasamba a mbande ya mpunga (Quintero-Calderón et al., 2021).
Ma Cytokinins amayimira mayankho a mbewu ku zovuta za abiotic, kuphatikiza kupsinjika kwa kutentha (Ha et al., 2012). Kuphatikiza apo, zanenedwa kuti kugwiritsa ntchito kunja kwa CK kumatha kuchepetsa kuwonongeka kwamafuta. Mwachitsanzo, kugwiritsa ntchito zeatin kunja kumawonjezera kuchuluka kwa photosynthetic, chlorophyll a ndi b, komanso kuyendetsa bwino kwa ma elekitironi mu zokwawa za bentgrass (Agrotis estolonifera) panthawi ya kutentha (Xu ndi Huang, 2009; Jespersen ndi Huang, 2015). Kugwiritsa ntchito kwambiri zeatin kungathenso kupititsa patsogolo ntchito ya antioxidant, kumapangitsanso kaphatikizidwe ka mapuloteni osiyanasiyana, kuchepetsa kuwonongeka kwa mitundu ya okosijeni (ROS) ndi malondialdehyde (MDA) kupanga muzomera za zomera (Chernyadyev, 2009; Yang et al., 2009). , 2016; Kumar et al., 2020).
Kugwiritsa ntchito gibberellic acid kwawonetsanso kuyankha kwabwino pakupsinjika kwa kutentha. Kafukufuku wasonyeza kuti GA biosynthesis imagwirizanitsa njira zosiyanasiyana za kagayidwe kachakudya ndikuwonjezera kulolerana pansi pa kutentha kwakukulu (Alonso-Ramirez et al. 2009; Khan et al. 2020). Abdel-Nabi et al. (2020) adapeza kuti kupopera mbewu mankhwalawa kwa exogenous GA (25 kapena 50 mg*L) kumatha kukulitsa kuchuluka kwa photosynthetic ndi antioxidant muzomera zamalalanje zopanikizika ndi kutentha poyerekeza ndi zomera zowongolera. Zawonedwanso kuti kugwiritsa ntchito kunja kwa HA kumawonjezera chinyezi, chlorophyll ndi carotenoid zomwe zili mkati ndikuchepetsa lipid peroxidation mu kanjedza (Phoenix dactylifera) pakupsinjika kwa kutentha (Khan et al., 2020). Auxin amakhalanso ndi gawo lofunikira pakuwongolera mayankho osinthika akukula kwa kutentha kwambiri (Sun et al., 2012; Wang et al., 2016). Kukula uku kumagwira ntchito ngati chizindikiro cha biochemical m'njira zosiyanasiyana monga kaphatikizidwe ka proline kapena kuwonongeka pansi pa kupsinjika kwa abiotic (Ali et al. 2007). Kuphatikiza apo, AUX imathandiziranso ntchito ya antioxidant, yomwe imapangitsa kuchepa kwa MDA muzomera chifukwa cha kuchepa kwa lipid peroxidation (Bielach et al., 2017). Sergeev ndi al. (2018) adawona kuti muzomera za nandolo (Pisum sativum) pansi pa kupsinjika kwa kutentha, zomwe zili mu proline - dimethylaminoethoxycarbonylmethyl)naphthylchloromethyl ether (TA-14) zimawonjezeka. Pakuyesa komweko, adawonanso milingo yotsika ya MDA m'zomera zotetezedwa poyerekeza ndi mbewu zomwe sizimathandizidwa ndi AUX.
Brassinosteroids ndi gulu lina la owongolera kukula omwe amagwiritsidwa ntchito kuchepetsa kupsinjika kwa kutentha. Ogweno et al. (2008) inanena kuti exogenous BR kutsitsi anawonjezera ukonde photosynthetic mlingo, stomatal conductance ndi pazipita mlingo wa Rubisco carboxylation wa phwetekere (Solanum lycopersicum) zomera pansi kutentha nkhawa kwa 8 masiku. Kupopera mbewu kwa foliar kwa epibrassinosteroids kumatha kukulitsa kuchuluka kwa photosynthetic ya nkhaka (Cucumis sativus) zomera pansi pa kutentha kwakukulu (Yu et al., 2004). Kuphatikiza apo, kugwiritsa ntchito kwakunja kwa BR kuchedwetsa kuwonongeka kwa chlorophyll ndikuwonjezera kugwiritsa ntchito madzi moyenera komanso kuchuluka kwa zokolola za PSII photochemistry muzomera zomwe zimapanikizika ndi kutentha (Holá et al., 2010; Toussagunpanit et al., 2015).
Chifukwa cha kusintha kwa nyengo komanso kusintha kwanyengo, mbewu za mpunga zimakumana ndi kutentha kwambiri tsiku lililonse (Lesk et al., 2016; Garcés, 2020; Federarroz (Federación Nacional de Arroceros), 2021). Mu phenotyping ya zomera, kugwiritsa ntchito phytonutrients kapena biostimulants kwaphunziridwa ngati njira yochepetsera kutentha kwa madera omwe amalima mpunga (Alvarado-Sanabria et al., 2017; Calderón-Páez et al., 2021; Quintero-Calderón et al., 2021). Kuonjezera apo, kugwiritsa ntchito mitundu yosiyanasiyana ya biochemical ndi physiological (kutentha kwa masamba, stomatal conductance, chlorophyll fluorescence parameters, chlorophyll ndi madzi okhudzana ndi madzi, malondialdehyde ndi proline synthesis) ndi chida chodalirika chowunikira zomera za mpunga pansi pa kutentha kwapakati ndi m'mayiko osiyanasiyana (Sánchez -Reynoso et al., Al. 2017; Komabe, kafukufuku wokhudzana ndi kugwiritsa ntchito mankhwala opopera a phytohormonal mumpunga amakhalabe osowa, chifukwa chake, kafukufuku wazomwe zimachitika pakugwiritsa ntchito zowongolera zakukula kwa mbewu ndizofunikira kwambiri pakuthana ndi zotsatira zoyipa za nthawi yanthawi yovutikira yazakudya za mpunga. chlorophyll fluorescence parameters ndi madzi achibale) ndi zotsatira za biochemical za foliar kugwiritsa ntchito zowongolera zinayi zakukula kwa mbewu (AUX, CK, GA ndi BR). (Photosynthetic pigments, malondialdehyde ndi proline contents) Zosintha mumitundu iwiri ya mpunga wamalonda womwe umakumana ndi kupsinjika kwa kutentha (kutentha kwausana/usiku).
Mu phunziro ili, mayesero awiri odziimira okha anachitidwa. Ma genotypes Federrose 67 (F67: genotype yopangidwa ndi kutentha kwambiri m'zaka khumi zapitazi) ndi Federrose 2000 (F2000: genotype yomwe idapangidwa mzaka khumi zapitazi zazaka za m'ma 1900 yowonetsa kukana kachilombo katsamba koyera) idagwiritsidwa ntchito koyamba. mbewu. ndi kuyesa kwachiwiri, motero. Mitundu yonse iwiri ya genotype imalimidwa kwambiri ndi alimi aku Colombia. Mbewu zofesedwa mu thireyi 10-L (kutalika 39.6 cm, m'lifupi 28.8 cm, kutalika 16.8 cm) munali mchenga loam nthaka ndi 2% organic kanthu. Mbewu zisanu zomwe zidamera kale zidabzalidwa muthireyi iliyonse. Ma pallets anayikidwa mu greenhouse wa Faculty of Agricultural Sciences of the National University of Colombia, Bogotá campus (43°50′56″ N, 74°04′051″ W), pamtunda wa 2556 m pamwamba pa nyanja (asl). m.) ndipo zidachitika kuyambira Okutobala mpaka Disembala 2019. Kuyesera kumodzi (Federroz 67) ndi kuyesa kwachiwiri (Federroz 2000) munyengo yomweyo ya 2020.
Mikhalidwe ya chilengedwe mu wowonjezera kutentha nthawi iliyonse yobzala ndi motere: kutentha kwa usana ndi usiku 30/25 ° C, chinyezi chachibale 60 ~ 80%, kujambula kwachilengedwe maola 12 (ma radiation a photosynthetically yogwira 1500 µmol (mafotoni) m-2 s-). 1 koloko). Zomera zidathiridwa feteleza molingana ndi zomwe zili mu chinthu chilichonse patatha masiku 20 mbewu zitamera (DAE), malinga ndi Sánchez-Reinoso et al. (2019): 670 mg nitrogen pa chomera, 110 mg phosphorous pachomera, 350 mg potaziyamu pachomera, 68 mg calcium pachomera, 20 mg magnesium pachomera, 20 mg sulfure pachomera, 17 mg silikoni pachomera. Zomera zimakhala ndi 10 mg boron pa chomera, 17 mg mkuwa pa chomera, ndi 44 mg zinki pa chomera chilichonse. Zomera za mpunga zidasungidwa mpaka 47 DAE pakuyesa kulikonse pomwe zidafika pagawo la phenological V5 panthawiyi. Kafukufuku wam'mbuyomu awonetsa kuti gawo la phenological iyi ndi nthawi yoyenera kuchita maphunziro opsinjika kutentha mu mpunga (Sánchez-Reinoso et al., 2014; Alvarado-Sanabria et al., 2017).
Pakuyesa kulikonse, ntchito ziwiri zosiyana za owongolera kukula kwa masamba zidachitika. Magulu oyamba opopera a foliar phytohormone adayikidwa masiku 5 isanafike chithandizo cha kutentha kwa kutentha (42 DAE) kuti akonzere mbewu kupsinjika kwa chilengedwe. Kupopera kwachiwiri kwa masamba kunaperekedwa patatha masiku asanu kuchokera pamene zomera zakumana ndi zovuta (52 DAE). Ma phytohrormones anayi adagwiritsidwa ntchito komanso katundu aliyense wogwira ntchito yomwe imawadwa mu kafukufukuyu amalembedwa motere. GA3); (iii) Cytokinin (trans-zeatin) 1 × 10-5 M (iv) Brassinosteroids [Spirostan-6-imodzi, 3,5-dihydroxy-, (3b,5a,25R)] 5 × 10-5; M. Zolinga izi zinasankhidwa chifukwa zimapangitsa mayankho abwino ndikuwonjezera kukana kwa zomera kupsinjika kwa kutentha (Zahir et al., 2001; Wen et al., 2010; El-Bassiony et al., 2012; Salehifar et al., 2017). Zomera za mpunga popanda zopopera zowongolera kukula kwa mbewu zimathiridwa ndi madzi osungunuka okha. Zomera zonse za mpunga zidapopera ndi chopopera pamanja. Ikani 20 ml H2O ku chomera kuti munyowetse pamwamba ndi pansi pa masamba. Kupopera mbewu kwa masamba onse kumagwiritsa ntchito adjuvant yaulimi (Agrotin, Bayer CropScience, Colombia) pa 0.1% (v/v). Mtunda pakati pa mphika ndi sprayer ndi 30 cm.
Thandizo la kupsinjika kwa kutentha linaperekedwa patatha masiku 5 pambuyo pa kupopera koyamba kwa foliar (47 DAE) pakuyesa kulikonse. Zomera za mpunga zidasamutsidwa kuchokera ku wowonjezera kutentha kupita kuchipinda chokulirapo cha 294 L (MLR-351H, Sanyo, IL, USA) kuti akhazikitse kupsinjika kwa kutentha kapena kusunga malo omwewo (47 DAE). Thandizo lophatikizana la kutentha kwapakati linachitidwa mwa kuika chipindacho ku kutentha kwa masana/usiku otsatirawa: kutentha kwa masana [40°C kwa maola asanu (kuyambira 11:00 mpaka 16:00)] ndi nyengo ya usiku [30°C kwa maola asanu] . Masiku 8 motsatizana (kuyambira 19:00 mpaka 24:00). Kutentha kwachisokonezo ndi nthawi yowonetsera zinasankhidwa malinga ndi maphunziro apitalo (Sánchez-Reynoso et al. 2014; Alvarado-Sanabría et al. 2017). Kumbali ina, gulu la zomera zomwe zimasamutsidwa ku chipinda chokulirapo zimasungidwa mu wowonjezera kutentha kutentha komweko (30 ° C masana / 25 ° C usiku) kwa masiku 8 otsatizana.
Pamapeto pa kuyesera, magulu ochiritsira otsatirawa adapezedwa: (i) kutentha kwa kukula + kugwiritsa ntchito madzi osungunuka [Absolute control (AC)], (ii) kutentha kwa kutentha + kugwiritsa ntchito madzi osungunuka [Kutentha kwa kutentha kwa thupi (SC)], (iii) chikhalidwe cha kutentha kwa kutentha + ntchito ya auxin (AUX), (iv) kutentha kwa kutentha + gibberellin ntchito (GA) + cytoCK application (GA), (vtoCK) + brassinosteroid (BR) Zowonjezera. Magulu ochizirawa adagwiritsidwa ntchito pamitundu iwiri ya genotypes (F67 ndi F2000). Zochizira zonse zidachitika mwachisawawa ndi zofananira zisanu, chilichonse chimakhala ndi chomera chimodzi. Chomera chilichonse chinagwiritsidwa ntchito powerengera zosinthika zomwe zatsimikiziridwa kumapeto kwa kuyesa. Kuyesera kunatenga 55 DAE.
Mayendedwe a stomatal (gs) adayezedwa pogwiritsa ntchito porosometer yonyamula (SC-1, METER Group Inc., USA) kuyambira 0 mpaka 1000 mmol m-2 s-1, yokhala ndi kabowo kakang'ono ka 6.35 mm. Miyezo imatengedwa polumikiza kafukufuku wa stomameter patsamba lokhwima ndi mphukira yayikulu ya mbewuyo itakulitsidwa. Pa chithandizo chilichonse, kuwerengera kwa gs kunkatengedwa pamasamba atatu a chomera chilichonse pakati pa 11:00 ndi 16:00 ndi kuwerengeredwa.
RWC idatsimikiziridwa molingana ndi njira yomwe Ghoulam et al. (2002). Tsamba lomwe lakulitsidwa bwino lomwe limagwiritsidwa ntchito kudziwa g lidagwiritsidwanso ntchito kuyeza RWC. Kulemera kwatsopano (FW) kunadziwika mwamsanga pambuyo pokolola pogwiritsa ntchito sikelo ya digito. Kenako masambawo ankawaika m’chidebe chapulasitiki chodzadza ndi madzi ndi kuwasiya mu mdima pa kutentha kwa firiji (22°C) kwa maola 48. Kenako yezani pa sikelo ya digito ndikulemba kulemera kowonjezereka (TW). Masamba otupa adawumitsidwa uvuni pa 75 ° C kwa maola 48 ndipo kulemera kwawo kowuma (DW) kunalembedwa.
Ma chlorophyll achibale ake adatsimikiziridwa pogwiritsa ntchito mita ya chlorophyll (atLeafmeter, FT Green LLC, USA) ndikufotokozedwa m'mayunitsi a atLeaf (Dey et al., 2016). Kuwerengera kokwanira kwa PSII (chiwerengero cha Fv/Fm) kudajambulidwa pogwiritsa ntchito chikoka cha chlorophyll fluorimeter (Handy PEA, Hansatech Instruments, UK). Masamba adasinthidwa ndi mdima pogwiritsa ntchito zingwe zamasamba kwa mphindi 20 musanafike muyeso wa Fv/Fm (Restrepo-Diaz ndi Garces-Varon, 2013). Masamba atatha mdima, maziko (F0) ndi fluorescence yapamwamba (Fm) adayesedwa. Kuchokera pazidziwitso izi, fluorescence yosinthika (Fv = Fm - F0), chiŵerengero cha fluorescence yosiyana kufika pa fluorescence (Fv / Fm), zokolola zambiri za PSII photochemistry (Fv / F0) ndi chiŵerengero cha Fm / F0 zinawerengedwa (Baker, 2008; Lee et al., 2017). Kuwerengera kwa chlorophyll ndi chlorophyll fluorescence kunatengedwa pamasamba omwewo omwe amagwiritsidwa ntchito poyezera gs.
Pafupifupi 800 mg ya masamba olemetsa atsopano adasonkhanitsidwa ngati mitundu yosiyanasiyana yazachilengedwe. Zitsanzo za masamba zinasinthidwa kukhala nayitrogeni wamadzimadzi ndikusungidwa kuti ziunikenso. Njira ya spectrometric yomwe imagwiritsidwa ntchito poyerekezera minofu ya chlorophyll a, b ndi carotenoid imachokera pa njira ndi ma equation omwe afotokozedwa ndi Wellburn (1994). Zitsanzo za minyewa ya masamba (30 mg) zidasonkhanitsidwa ndikuphatikizidwa mu 3 ml ya 80% acetone. Zitsanzozo zinali centrifuged (chitsanzo 420101, Becton Dickinson Primary Care Diagnostics, USA) pa 5000 rpm kwa mphindi 10 kuchotsa particles. Wopambana adachepetsedwa mpaka voliyumu yomaliza ya 6 ml powonjezera 80% acetone (Sims ndi Gamon, 2002). Zomwe zili mu chlorophyll zidatsimikiziridwa pa 663 (chlorophyll a) ndi 646 (chlorophyll b) nm, ndi carotenoids pa 470 nm pogwiritsa ntchito spectrophotometer (Spectronic BioMate 3 UV-vis, Thermo, USA).
Njira ya thiobarbituric acid (TBA) yofotokozedwa ndi Hodges et al. (1999) idagwiritsidwa ntchito kuyesa membrane lipid peroxidation (MDA). Pafupifupi 0,3 g ya minofu ya masamba idapangidwanso homogenized mu nayitrogeni yamadzimadzi. Zitsanzozo zinali centrifuged pa 5000 rpm ndipo absorbance anayesedwa pa spectrophotometer pa 440, 532 ndi 600 nm. Potsirizira pake, chiwerengero cha MDA chinawerengedwa pogwiritsa ntchito coefficient of extinction (157 M mL-1).
Proline zomwe zili m'mankhwala onse zidatsimikiziridwa pogwiritsa ntchito njira yofotokozedwa ndi Bates et al. (1973). Onjezani 10 ml ya 3% yamadzimadzi amadzimadzi a sulfosalicylic acid ku zitsanzo zosungidwa ndikusefa kudzera mu pepala losefera la Whatman (No. 2). Kenako 2 ml ya kusefera iyi idachitidwa ndi 2 ml ya ninhydric acid ndi 2 ml ya glacial acetic acid. The osakaniza anaikidwa mu osamba madzi pa 90 ° C kwa 1 ora. Lekani kuchitapo kanthu powaika pa ayezi. Gwirani chubu mwamphamvu pogwiritsa ntchito vortex shaker ndikusungunula yankho mu 4 ml ya toluene. Kuwerengera kwa Absorbance kunatsimikiziridwa pa 520 nm pogwiritsa ntchito spectrophotometer yomwe imagwiritsidwa ntchito poyesa ma pigment a photosynthetic (Spectronic BioMate 3 UV-Vis, Thermo, Madison, WI, USA).
Njira yofotokozedwa ndi Gerhards et al. (2016) kuwerengera kutentha kwa denga ndi CSI. Zithunzi zotentha zimatengedwa ndi kamera ya FLIR 2 (FLIR Systems Inc., Boston, MA, USA) ndi kulondola kwa ± 2 ° C kumapeto kwa nthawi yopanikizika. Ikani malo oyera kumbuyo kwa chomera kuti mujambule. Apanso, mafakitale awiri adawonedwa ngati zitsanzo. Zomerazo zidayikidwa pamalo oyera; imodzi idakutidwa ndi adjuvant yaulimi (Agrotin, Bayer CropScience, Bogotá, Colombia) kutengera kutsegulira kwa stomata [yonyowa (Twet)], ndipo inayo inali tsamba yopanda ntchito [Dry mode (Tdry)] (Castro -Duque et al., 2020). Mtunda pakati pa kamera ndi mphika panthawi yojambula unali 1 m.
Chiwerengero cha kulekerera kwachibale chinawerengedwa molakwika pogwiritsa ntchito stomatal conductance (gs) ya zomera zowonongeka poyerekeza ndi zomera zowongolera (zomera zopanda kupsinjika maganizo komanso zowongolera kukula zomwe zimagwiritsidwa ntchito) kuti zizindikire kulekerera kwa ma genotypes omwe amayesedwa mu phunziroli. RTI idapezedwa pogwiritsa ntchito equation yosinthidwa kuchokera ku Chávez-Arias et al. (2020).
Pakuyesa kulikonse, zosintha zonse zathupi zomwe zatchulidwa pamwambapa zidatsimikiziridwa ndikujambulidwa ku 55 DAE pogwiritsa ntchito masamba okulitsidwa bwino omwe amasonkhanitsidwa kuchokera padenga lapamwamba. Kuonjezera apo, miyeso inkachitidwa mu chipinda chokulirapo kuti asasinthe malo omwe zomera zimamera.
Deta kuchokera ku mayesero oyambirira ndi achiwiri adafufuzidwa pamodzi monga mndandanda wa zoyesera. Gulu lirilonse loyesera linali ndi zomera 5, ndipo chomera chilichonse chinali ndi gawo loyesera. Kusanthula kwa kusiyana (ANOVA) kunachitika (P ≤ 0.05). Pamene kusiyana kwakukulu kunazindikirika, kuyesa kwa Tukey's post hoc kunagwiritsidwa ntchito pa P ≤ 0.05. Gwiritsani ntchito arcsine kuti musinthe maperesenti. Deta idawunikidwa pogwiritsa ntchito Statistix v 9.0 software (Analytical Software, Tallahassee, FL, USA) ndikukonza pogwiritsa ntchito SigmaPlot (version 10.0; Systat Software, San Jose, CA, USA). Kusanthula kwachigawo chachikulu kunachitika pogwiritsa ntchito pulogalamu ya InfoStat 2016 (Analysis Software, National University of Cordoba, Argentina) kuti azindikire owongolera bwino kwambiri akukula kwa mbewu omwe akuphunziridwa.
Table 1 ikufotokoza mwachidule za ANOVA yowonetsa zoyeserera, machiritso osiyanasiyana, ndi kuyanjana kwawo ndi masamba a photosynthetic pigments (chlorophyll a, b, total, and carotenoids), malondialdehyde (MDA) ndi proline content, and stomatal conductance. Zotsatira za gs, zomwe zili ndi madzi. (RWC), chlorophyll content, chlorophyll alpha fluorescence parameters, crown temperature (PCT) (°C), crop stress index (CSI) and related tolerance index of rice plant at 55 DAE.
Table 1. Chidule cha ANOVA deta pa mpunga physiological ndi biochemical variables pakati kuyesera (genotypes) ndi kutentha nkhawa mankhwala.
Kusiyanitsa (P≤0.01) mu kuyanjana kwa masamba a photosynthetic pigment, zokhudzana ndi chlorophyll (mawerengedwe a Atleaf), ndi magawo a alpha-chlorophyll fluorescence pakati pa zoyesera ndi mankhwala akuwonetsedwa mu Table 2. Kutentha kwakukulu kwa masana ndi usiku kunachulukitsa zonse za chlorophyll ndi carotenoid. Mbande za mpunga zopanda utsi wa ma phytohormones (2.36 mg g-1 wa “F67″ ndi 2.56 mg g-1 wa “F2000″) poyerekeza ndi mbewu zomwe zimamera pansi pa kutentha koyenera (2.67 mg g -1)) zimawonetsa kutsika kwa chlorophyll. Muzoyesera zonse ziwiri, "F67" inali 2.80 mg g-1 ndipo "F2000" inali 2.80 mg g-1. Kuonjezera apo, mbande za mpunga zomwe zimagwiritsidwa ntchito ndi mankhwala opopera a AUX ndi GA pansi pa kupsinjika kwa kutentha zinawonetsanso kuchepa kwa chlorophyll mu genotypes (AUX = 1.96 mg g-1 ndi GA = 1.45 mg g-1 ya "F67" ; AUX = 1.96 mg g-1 ndi GA = 5 mg G-1 = "F6" = 1. 2.24 mg) g-1 ndi GA = 1.43 mg g-1 (kwa "F2000" ) pansi pa zovuta za kutentha. Pansi pa kupsinjika kwa kutentha, chithandizo cha foliar ndi BR chinapangitsa kuwonjezeka pang'ono kwa kusinthaku m'ma genotypes onse. Pomaliza, kutsitsi kwa CK foliar kunawonetsa mayendedwe apamwamba kwambiri a photosynthetic pigment pakati pamankhwala onse (AUX, GA, BR, SC ndi AC mankhwala) mu genotypes F67 (3.24 mg g-1) ndi F2000 (3.65 mg g-1). Zomwe zili mu chlorophyll (Atleaf unit) zinachepetsedwanso ndi kupsinjika kwa kutentha. Makhalidwe apamwamba adalembedwanso muzomera zopopera ndi CC mumitundu yonse iwiri (41.66 ya "F67" ndi 49.30 ya "F2000"). Fv ndi Fv/Fm ziwerengero zinawonetsa kusiyana kwakukulu pakati pa mankhwala ndi cultivars (Table 2). Ponseponse, pakati pa mitundu iyi, cultivar F67 inali yochepa kutenthedwa ndi kutentha kusiyana ndi cultivar F2000. Ma Fv ndi Fv/Fm adavutika kwambiri pakuyesa kwachiwiri. Mbande zokhazikika za 'F2000′ zomwe sizinapopedwe ndi ma phytohormones zinali ndi ma Fv otsika kwambiri (2120.15) ndi Fv/Fm ratios (0.59), koma kupopera mbewu mankhwalawa ndi CK kunathandizira kubwezeretsa izi (Fv: 2591, 89, Fv/Fm 3 chiŵerengero): 0. , kulandira zowerengera zofanana ndi zomwe zinalembedwa pa zomera za "F2000" zomwe zimakula pansi pa kutentha kwabwino (Fv: 2955.35, Fv / Fm chiŵerengero: 0.73: 0.72). Panalibe kusiyana kwakukulu koyambirira kwa fluorescence (F0), fluorescence (Fm), chiwerengero cha photochemical quantum cha PSII (Fv / F0) ndi Fm / F0 chiŵerengero. Pomaliza, BR inawonetsa zofanana ndi zomwe zimawonedwa ndi CK (Fv 2545.06, Fv/Fm chiŵerengero 0.73).
Tebulo 2. Zotsatira za kupsinjika kwa kutentha kophatikizana (40°/30°C usana/usiku) pa masamba a photosynthetic pigments [total chlorophyll (Chl Total), chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids Cx+c] effect ], relative chlorophyll content, chlorosceliffancell content (Actriniophyll). fluorescence (F0), fluorescence pazipita (Fm), variable fluorescence (Fv), pazipita PSII dzuwa (Fv/Fm), photochemical pazipita quantum zokolola za PSII (Fv/F0) ndi Fm/F0 mu zomera awiri mpunga genotypes [Federrose 67 (F67) ndi Federrose 00 pambuyo 50 masiku 20 pambuyo 50 (DAE)).
Wachibale madzi okhutira (RWC) osiyana ankachitira mpunga zomera anasonyeza kusiyana (P ≤ 0.05) mu mogwirizana ndi experimental ndi foliar mankhwala (mkuyu. 1A). Mukathandizidwa ndi SA, zotsika kwambiri zidalembedwa ma genotypes onse (74.01% ya F67 ndi 76.6% ya F2000). Pansi pa kutentha kwa kutentha, RWC ya zomera za mpunga za ma genotypes omwe amathandizidwa ndi ma phytohormones osiyanasiyana adakula kwambiri. Ponseponse, kugwiritsa ntchito masamba a CK, GA, AUX, kapena BR kudachulukitsa RWC kuti ikhale yofanana ndi ya zomera zomwe zidakula pansi pamikhalidwe yabwino panthawi yoyesera. Kuwongolera kotheratu ndi zomera zopopera masamba zojambulidwa zamtengo pafupifupi 83% pamitundu yonse iwiri. Kumbali inayi, gs adawonetsanso kusiyana kwakukulu (P ≤ 0.01) mu mgwirizano woyesera-mankhwala (mkuyu 1B). Chomera chowongolera (AC) chinalembanso zamtengo wapatali pamtundu uliwonse wamtundu (440.65 mmol m-2s-1 wa F67 ndi 511.02 mmol m-2s-1 wa F2000). Zomera za mpunga zomwe zimakhudzidwa ndi kutentha kwaphatikizidwe kokha zimawonetsa zotsika kwambiri za gs pamitundu yonse iwiri (150.60 mmol m-2s-1 pa F67 ndi 171.32 mmol m-2s-1 pa F2000). Chithandizo cha foliar ndi zowongolera zonse za kukula kwa mbewu zawonjezekanso g. Pamitengo ya mpunga ya F2000 yopopera mankhwala ndi CC, zotsatira za kupopera mbewu mankhwalawa ndi ma phytohormones zinali zoonekeratu. Gulu ili la zomera silinawonetse kusiyana kulikonse poyerekeza ndi zomera zowonongeka (AC 511.02 ndi CC 499.25 mmol m-2s-1).
Chithunzi 1. Zotsatira za kutentha kwapang'onopang'ono (40 ° / 30 ° C usana / usiku) pazomwe zili ndi madzi (RWC) (A), stomatal conductance (gs) (B), malondialdehyde (MDA) kupanga (C), ndi proline content . (D) m'zomera zamitundu iwiri ya mpunga (F67 ndi F2000) pakadutsa masiku 55 mutamera (DAE). Zochizira zomwe zimayesedwa pamtundu uliwonse wa genotype zikuphatikizapo: kulamulira kwathunthu (AC), kulamulira kutentha kwa kutentha (SC), kutentha kwa kutentha + auxin (AUX), kutentha kwa kutentha + gibberellin (GA), kutentha kwa kutentha + cell mitogen (CK), ndi kutentha kwa kutentha + brassinosteroid. (BR). Chigawo chilichonse chikuyimira cholakwika ± chokhazikika cha mfundo zisanu za data (n = 5). Mizere yotsatiridwa ndi zilembo zosiyanasiyana imasonyeza kusiyana kwakukulu malinga ndi mayeso a Tukey (P ≤ 0.05). Zilembo zokhala ndi chikwangwani chofanana zikuwonetsa kuti tanthauzo silofunikira (≤ 0.05).
MDA (P ≤ 0.01) ndi proline (P ≤ 0.01) zomwe zili mkati zinawonetsanso kusiyana kwakukulu pakati pa kuyesera ndi mankhwala a phytohormone (mkuyu 1C, D). Kuchuluka kwa lipid peroxidation kunawonedwa ndi chithandizo cha SC mumitundu yonse iwiri (Chithunzi 1C), komabe mbewu zothandizidwa ndi utsi wowongolera masamba zidawonetsa kuchepa kwa lipid peroxidation mumitundu yonse iwiri; Nthawi zambiri, kugwiritsa ntchito ma phytohormones (CA, AUC, BR kapena GA) kumabweretsa kuchepa kwa lipid peroxidation (za MDA). Palibe kusiyana komwe kunapezeka pakati pa zomera za AC za mitundu iwiri ya genotypes ndi zomera pansi pa kutentha kwa kutentha ndikupopera ndi phytohormones (zowona za FW muzomera za "F67" zinkachokera ku 4.38-6.77 µmol g-1, ndi mu FW "F2000" zomera "zinkawoneka zotsika kuchokera ku 92.18 g mpaka 18 g) dzanja, kaphatikizidwe ka proline mu "F67" zomera anali otsika kuposa "F2000" zomera pansi pa kupsyinjika pamodzi, zomwe zinachititsa kuti kuchulukitsidwa kwa proline zopangira mpunga wopanikizika kutentha, mu mayesero onse awiri, izo zinaonedwa kuti utsogoleri wa mahomoni amenewa kwambiri kuchuluka kwa amino asidi okhutira F2000 zomera (AUX ndi BR4 4 g - 118 g) kulemekeza. (mkuyu 1G).
Zotsatira za foliar plant growth regulator spray ndi kuphatikiza kutentha kwa kutentha kwa zomera ndi index tolerance index (RTI) zikuwonetsedwa mu Zithunzi 2A ndi B. Pamitundu yonse ya genotype, kutentha kwa AC zomera kunali pafupi ndi 27 ° C, ndipo zomera za SC zinali pafupi ndi 28 ° C. NDI. Zinawonedwanso kuti machiritso a foliar ndi CK ndi BR adachepetsa kutentha kwa 2-3 ° C poyerekeza ndi mbewu za SC (Chithunzi 2A). RTI inasonyeza khalidwe lofanana ndi zosintha zina za thupi, kusonyeza kusiyana kwakukulu (P ≤ 0.01) mu mgwirizano pakati pa kuyesa ndi chithandizo (Chithunzi 2B). Zomera za SC zidawonetsa kulekerera kwamitengo yotsika m'mitundu yonse iwiri (34.18% ndi 33.52% pamitengo yampunga ya "F67" ndi "F2000", motsatana). Kudyetsa foliar kwa phytohormones kumathandizira RTI muzomera zomwe zimakhudzidwa ndi kutentha kwambiri. Izi zidadziwika kwambiri muzomera za "F2000" zopopera ndi CC, pomwe RTI inali 97.69. Komano, kusiyana kwakukulu kunawonedwa kokha mu zokolola zamaganizo (CSI) za zomera za mpunga pansi pa foliar factor spray stress stress (P ≤ 0.01) (mkuyu. 2B). Zomera za mpunga zokha zomwe zidakhudzidwa kwambiri ndi kutentha kwambiri zidawonetsa kupsinjika kwambiri (0.816). Zomera za mpunga zikathiridwa ndi ma phytohormones osiyanasiyana, index ya kupsinjika inali yotsika (zoyambira 0,6 mpaka 0,67). Pomaliza, mbewu ya mpunga yomwe idakula pansi pamikhalidwe yabwino inali ndi mtengo wa 0,138.
Chithunzi 2. Zotsatira za kupsinjika kwa kutentha (40°/30°C usana/usiku) pa kutentha kwa denga (A), index tolerance index (RTI) (B), ndi crop stress index (CSI) (C) za mitundu iwiri ya zomera. Ma genotypes a mpunga wamalonda (F67 ndi F2000) adalandira chithandizo cha kutentha kosiyanasiyana. Zochizira zomwe zimayesedwa pamtundu uliwonse wa genotype zikuphatikizapo: kulamulira kwathunthu (AC), kulamulira kutentha kwa kutentha (SC), kutentha kwa kutentha + auxin (AUX), kutentha kwa kutentha + gibberellin (GA), kutentha kwa kutentha + cell mitogen (CK), ndi kutentha kwa kutentha + brassinosteroid. (BR). Kutentha kophatikizana kumaphatikizapo kuyika mbewu za mpunga ku kutentha kwa masana/usiku (40°/30°C usana/usiku). Chigawo chilichonse chikuyimira cholakwika ± chokhazikika cha mfundo zisanu za data (n = 5). Mizere yotsatiridwa ndi zilembo zosiyanasiyana imasonyeza kusiyana kwakukulu malinga ndi mayeso a Tukey (P ≤ 0.05). Zilembo zokhala ndi chikwangwani chofanana zikuwonetsa kuti tanthauzo silofunikira (≤ 0.05).
Principal component analysis (PCA) inasonyeza kuti zosinthika zomwe zinayesedwa pa 55 DAE zinafotokozera 66.1% ya mayankho a thupi ndi a biochemical a zomera za mpunga zomwe zimakhudzidwa ndi kutentha zomwe zimagwiritsidwa ntchito ndi kupopera kwa kukula (mkuyu 3). Ma Vectors amayimira zosinthika ndipo madontho amayimira zowongolera kukula kwa zomera (GRs). Ma vectors a gs, chlorophyll content, maximum quantum performance of PSII (Fv/Fm) ndi biochemical parameters (TChl, MDA ndi proline) ali pafupi kwambiri ndi chiyambi, kusonyeza kugwirizana kwakukulu pakati pa khalidwe la thupi la zomera ndi iwo. kusintha. Gulu limodzi (V) linaphatikizapo mbande za mpunga zomwe zabzalidwa pa kutentha koyenera (AT) ndi F2000 zomera zothiridwa ndi CK ndi BA. Pa nthawi yomweyo, ambiri zomera ankachitira ndi GR anapanga osiyana gulu (IV), ndi mankhwala ndi GA mu F2000 anapanga gulu osiyana (II). Mosiyana ndi izi, mbande za mpunga zotenthedwa ndi kutentha (magulu I ndi III) opanda utsi wa foliar wa ma phytohormones (ma genotypes onse anali SC) anali m'dera loyang'anizana ndi gulu V, kusonyeza zotsatira za kutentha kwa thupi pa zomera. .
Chithunzi 3. Kusanthula mwatsatanetsatane za zotsatira za kupsinjika kwa kutentha (40 ° / 30 ° C usana / usiku) pa zomera zamitundu iwiri ya mpunga (F67 ndi F2000) pamasiku 55 pambuyo pa kutuluka (DAE). Chidule cha AC F67, kulamulira kwathunthu F67; SC F67, kuwongolera kutentha kwapakati F67; AUX F67, kupsinjika kwa kutentha + auxin F67; GA F67, kutentha kupanikizika + gibberellin F67; CK F67, kupsinjika kwa kutentha + magawo a cell BR F67, kupsinjika kwa kutentha + brassinosteroid. F67; AC F2000, kulamulira kwathunthu F2000; SC F2000, Kuwongolera Kupsinjika kwa Kutentha F2000; AUX F2000, kupsinjika kwa kutentha + auxin F2000; GA F2000, kutentha nkhawa + gibberellin F2000; CK F2000, kupsinjika kwa kutentha + cytokinin, BR F2000, kupsinjika kwa kutentha + mkuwa steroid; F2000.
Zosintha monga chlorophyll content, stomatal conductance, Fv/Fm ratio, CSI, MDA, RTI ndi proline content zingathandize kumvetsetsa kusintha kwa mtundu wa mpunga ndikuwunika momwe njira za agronomic zimakhudzira kutentha (Sarsu et al., 2018; Quintero-Calderon et al., 2021). Cholinga cha kuyesera kumeneku chinali kuyesa zotsatira za ntchito ya olamulira anayi kukula pa zokhudza thupi ndi biochemical magawo a mbande mpunga pansi zovuta kutentha mavuto. Kuyesa mbande ndi njira yosavuta komanso yofulumira yowunika nthawi imodzi ya mbewu za mpunga kutengera kukula kapena momwe zinthu ziliri (Sarsu et al. 2018). Zotsatira za phunziroli zikuwonetsa kuti kupsinjika kwa kutentha kophatikizana kumapangitsa mayankho osiyanasiyana amthupi ndi biochemical mumitundu iwiri ya mpunga, zomwe zikuwonetsa kusintha. Zotsatirazi zikuwonetsanso kuti zopopera zowongolera kukula kwa foliar (makamaka cytokinins ndi brassinosteroids) zimathandizira mpunga kuti ugwirizane ndi kupsinjika kwa kutentha komwe kumakhudza makamaka gs, RWC, Fv/Fm ratio, photosynthetic pigments ndi proline content.
Kugwiritsiridwa ntchito kwa zowongolera kukula kumathandizira kukonza momwe madzi a mbewu za mpunga amakhalira ndi kutentha, komwe kumatha kulumikizidwa ndi kupsinjika kwakukulu komanso kutsika kwamitengo yamitengo. Kafukufukuyu adawonetsa kuti pakati pa zomera za "F2000" (zotengera mtundu wa genotype), mbewu za mpunga zomwe zimagwiritsidwa ntchito makamaka ndi CK kapena BR zinali ndi ma gs apamwamba komanso otsika kwambiri a PCT kuposa mbewu zomwe zimathandizidwa ndi SC. Kafukufuku wam'mbuyomu adawonetsanso kuti gs ndi PCT ndi zolondola zokhudzana ndi thupi zomwe zimatha kudziwa momwe mungayankhire mbewu za mpunga ndi zotsatira za njira za agronomic pakupsinjika kwa kutentha (Restrepo-Diaz ndi Garces-Varon, 2013; Sarsu et al., 2018; Quintero). -Carr DeLong et al., 2021). Leaf CK kapena BR imakulitsa g pansi pa kupsinjika chifukwa mahomoni omera amatha kulimbikitsa kutsegula kwa stomatal kudzera muzochita zopangira mamolekyu ena osayina monga ABA (olimbikitsa kutseka kwa stomatal pansi pamavuto abiotic) (Macková et al., 2013; Zhou et al., 2013). 2013). ). , 2014). Kutsegula kwa stomatal kumalimbikitsa kuziziritsa kwa masamba ndikuthandizira kuchepetsa kutentha kwa denga (Sonjaroon et al., 2018; Quintero-Calderón et al., 2021). Pazifukwa izi, kutentha kwa denga la mbewu zampunga zopopera mbewu mankhwalawa ndi CK kapena BR kumatha kutsika ndi kupsinjika kwa kutentha.
Kupsinjika kwakukulu kwa kutentha kumatha kuchepetsa masamba a photosynthetic pigment (Chen et al., 2017; Ahammed et al., 2018). Mu phunziro ili, pamene zomera za mpunga zinali pansi pa kutentha kwa kutentha ndipo sizinapopedwe ndi zowongolera za kukula kwa zomera, mitundu ya photosynthetic inki imakonda kuchepa mu ma genotypes (Table 2). Feng ndi al. (2013) adanenanso za kuchepa kwakukulu kwa chlorophyll m'masamba amitundu iwiri ya tirigu yomwe imakhudzidwa ndi kupsinjika kwa kutentha. Kuwonetsa kutentha kwambiri nthawi zambiri kumabweretsa kuchepa kwa chlorophyll, zomwe zitha kukhala chifukwa cha kuchepa kwa chlorophyll biosynthesis, kuwonongeka kwa ma pigment, kapena kuphatikiza kwawo pakupsinjika kwa kutentha (Fahad et al., 2017). Komabe, mbewu za mpunga zomwe zimathandizidwa makamaka ndi CK ndi BA zidawonjezera kuchuluka kwa ma photosynthetic inki chifukwa cha kutentha kwambiri. Zotsatira zofananazi zinanenedwanso ndi Jespersen and Huang (2015) ndi Suchsagunpanit et al. (2015), yemwe adawona kuwonjezeka kwa masamba a chlorophyll kutsatira kugwiritsa ntchito zeatin ndi ma epibrassinosteroid mahomoni mu bentgrass wopanikizika ndi mpunga, motsatana. Kufotokozera komveka chifukwa chake CK ndi BR zimalimbikitsa kuwonjezeka kwa masamba a chlorophyll pansi pa kupsinjika kwa kutentha kwapang'onopang'ono ndikuti CK ikhoza kupititsa patsogolo kuyambika kosalekeza kwa olimbikitsa mawu (monga senescence-activating promotioner (SAG12) kapena HSP18 promotioner) ndi kuchepetsa kutaya kwa chlorophyll m'masamba. , kuchedwetsa kumera kwa masamba ndikuwonjezera kukana kwa mbewu kutentha (Liu et al., 2020). BR imatha kuteteza tsamba la chlorophyll ndikuwonjezera masamba a chlorophyll poyambitsa kapena kuyambitsa kaphatikizidwe ka michere yomwe imakhudzidwa ndi chlorophyll biosynthesis pansi pamavuto (Sharma et al., 2017; Siddiqui et al., 2018). Pomaliza, ma phytohormones awiri (CK ndi BR) amalimbikitsanso kuwonetsa kwa mapuloteni owopsa komanso kusintha njira zosiyanasiyana zosinthira kagayidwe kachakudya, monga kuchuluka kwa chlorophyll biosynthesis (Sharma et al., 2017; Liu et al., 2020).
Chlorophyll a fluorescence parameters amapereka njira yofulumira komanso yosawononga yomwe ingayese kulekerera kwa zomera kapena kusintha kwa abiotic stress mikhalidwe (Chaerle et al. 2007; Kalaji et al. 2017). Magawo monga chiŵerengero cha Fv / Fm akhala akugwiritsidwa ntchito ngati zizindikiro za kusintha kwa zomera kuti zikhale zovuta (Alvarado-Sanabria et al. 2017; Chavez-Arias et al. 2020). Mu kafukufukuyu, mbewu za SC zidawonetsa zotsika kwambiri pazosinthika izi, makamaka "F2000" za mpunga. Yin et al. (2010) adapezanso kuti chiŵerengero cha Fv/Fm cha masamba olima kwambiri ampunga chinachepa kwambiri pa kutentha pamwamba pa 35°C. Malinga ndi Feng et al. (2013), m'munsi Fv/Fm chiŵerengero pansi kutentha nkhawa limasonyeza kuti mlingo wa malemeredwe mphamvu kugwidwa ndi kutembenuka ndi PSII likulu anachita yafupika, kusonyeza kuti PSII anachita pakati disintegrates ndi kutentha nkhawa. Kuwona uku kumatithandiza kunena kuti kusokonezeka kwa zida za photosynthetic kumawonekera kwambiri mumitundu yovuta (Fedearroz 2000) kuposa mitundu yosamva (Fedearroz 67).
Kugwiritsa ntchito CK kapena BR nthawi zambiri kumathandizira magwiridwe antchito a PSII pansi pazovuta za kutentha. Zotsatira zofananazo zinapezedwa ndi Suchsagunpanit et al. (2015), yemwe adawona kuti kugwiritsa ntchito BR kumawonjezera mphamvu ya PSII pansi pa kutentha kwa mpunga. Kumar et al. (2020) adapezanso kuti mbewu zachickpea zomwe zimathandizidwa ndi CK (6-benzyladenine) komanso kupsinjika kwa kutentha zimachulukitsa chiŵerengero cha Fv/Fm, pomaliza kuti kugwiritsa ntchito CK poyambitsa zeaxanthin pigment cycle kumalimbikitsa ntchito ya PSII. Kuonjezera apo, kutsitsi kwa tsamba la BR kunkakonda PSII photosynthesis pansi pa zovuta zophatikizana, zomwe zimasonyeza kuti kugwiritsa ntchito phytohormone iyi kunapangitsa kuti kuchepa kwa mphamvu ya PSII kuwonongeke komanso kumalimbikitsa kudzikundikira kwa mapuloteni ang'onoang'ono a kutentha kwa chloroplasts (Ogweno et al. 2008; Kothari ndi Lachowitz). , 2021).
MDA ndi proline zomwe zili mkati nthawi zambiri zimawonjezeka pamene zomera zili pansi pa zovuta zowonongeka poyerekeza ndi zomera zomwe zimakula bwino (Alvarado-Sanabria et al. 2017). Kafukufuku wam'mbuyo adawonetsanso kuti ma MDA ndi ma proline ali ndi zizindikiro za biochemical zomwe zingagwiritsidwe ntchito kumvetsetsa njira yosinthira kapena kukhudzidwa kwa machitidwe a agronomic mu mpunga pansi pa kutentha kwa masana kapena usiku (Alvarado-Sanabria et al., 2017; Quintero-Calderón et al. . , 2021). Maphunzirowa adawonetsanso kuti MDA ndi zomwe zili mu proline zimakhala zokwera kwambiri muzomera za mpunga zomwe zimawonekera kutentha kwambiri usiku kapena masana, motsatana. Komabe, kupopera mbewu mankhwalawa kwa CK ndi BR kunathandizira kuchepa kwa MDA ndi kuwonjezeka kwa ma proline, makamaka mu genotype yolekerera (Federroz 67). Kupopera kwa CK kumatha kulimbikitsa kuwonjezereka kwa cytokinin oxidase/dehydrogenase, potero kumawonjezera zomwe zili muzinthu zoteteza monga betaine ndi proline (Liu et al., 2020). BR imalimbikitsa kulowetsedwa kwa osmoprotectants monga betaine, shuga, ndi amino acid (kuphatikiza proline yaulere), kusunga ma cell osmotic molingana ndi zovuta zambiri zachilengedwe (Kothari ndi Lachowiec, 2021).
Crop stress index (CSI) ndi relarance tolerance index (RTI) amagwiritsidwa ntchito kuti adziwe ngati mankhwala omwe akuwunikidwa amathandizira kuchepetsa nkhawa zosiyanasiyana (abiotic ndi biotic) komanso kukhala ndi zotsatira zabwino pazachilengedwe za zomera (Castro-Duque et al., 2020; Chavez-Arias et al., 2020). Makhalidwe a CSI amatha kuchoka pa 0 mpaka 1, kuyimira kusakhala ndi nkhawa komanso kupsinjika, motsatana (Lee et al., 2010). Miyezo ya CSI ya zomera zotenthedwa ndi kutentha (SC) idachokera ku 0.8 mpaka 0.9 (Chithunzi 2B), kuwonetsa kuti mbewu za mpunga zidakhudzidwa ndi kupsinjika kophatikizana. Komabe, kupopera mbewu mankhwalawa kwa BC (0.6) kapena CK (0.6) makamaka kudapangitsa kuti chizindikiritsochi chichepe pansi pazovuta za abiotic poyerekeza ndi mbewu za mpunga za SC. Mu zomera za F2000, RTI inawonetsa kuwonjezeka kwakukulu pogwiritsa ntchito CA (97.69%) ndi BC (60.73%) poyerekeza ndi SA (33.52%), zomwe zimasonyeza kuti olamulira akukula kwa zomera amathandizanso kuwongolera kuyankha kwa mpunga ku kulolerana kwa kapangidwe kake. Kutentha kwambiri. Ma indices awa aperekedwa kuti azitha kuyang'anira zovuta zamitundu yosiyanasiyana. Kafukufuku wopangidwa ndi Lee et al. (2010) adawonetsa kuti CSI yamitundu iwiri ya thonje pansi pa kupsinjika kwa madzi pang'ono inali pafupifupi 0,85, pomwe ma CSI amitundu yothiriridwa bwino adachokera ku 0,4 mpaka 0,6, pomaliza kuti cholozera ichi ndi chizindikiro cha kusintha kwamadzi kwa mitundu. mikhalidwe yodetsa nkhawa. Komanso, Chavez-Arias et al. (2020) adawunika momwe zimagwirira ntchito zopangira zopanga monga njira yothanirana ndi nkhawa muzomera za C. elegans ndipo zidapeza kuti mbewu zopoperedwa ndi mankhwalawa zimawonetsa RTI yapamwamba (65%). Kutengera zomwe tafotokozazi, CK ndi BR zitha kuonedwa ngati njira za agronomic zomwe cholinga chake ndi kukulitsa kulolerana kwa mpunga ku zovuta za kutentha, chifukwa zowongolera zakukula kwa mbewuzi zimathandizira kuyankhidwa kwachilengedwe kwachilengedwe ndi thupi.
M'zaka zingapo zapitazi, kafukufuku wa mpunga ku Colombia wakhala akuyang'ana kwambiri kuyesa ma genotypes olekerera kutentha kwa masana kapena usiku pogwiritsa ntchito makhalidwe a thupi kapena biochemical (Sánchez-Reinoso et al., 2014; Alvarado-Sanabria et al., 2021). Komabe, m'zaka zingapo zapitazi, kusanthula kwa matekinoloje othandiza, azachuma komanso opindulitsa kwakhala kofunika kwambiri kuti apereke kasamalidwe ka mbewu zophatikizika kuti apititse patsogolo zotsatira za nthawi yovuta ya kutentha kwa dziko (Calderón-Páez et al., 2021; Quintero-Calderon et al., 2021) . Choncho, kuyankhidwa kwa thupi ndi biochemical kwa zomera za mpunga ku zovuta za kutentha (40 ° C tsiku / 30 ° C usiku) zomwe zimawonedwa mu kafukufukuyu zikusonyeza kuti kupopera mbewu mankhwalawa ndi CK kapena BR kungakhale njira yoyenera yosamalira mbewu kuti muchepetse zotsatira zoipa. Zotsatira za nthawi ya kutentha kwapakati. Mankhwalawa amathandizira kulolerana kwamitundu yonse ya mpunga (otsika CSI ndi RTI yayikulu), kuwonetsa momwe zimayankhira pazokhudza thupi komanso zamankhwala am'mera pansi pa kupsinjika kwa kutentha. Yankho lalikulu la zomera za mpunga linali kuchepa kwa zomwe zili mu GC, chlorophyll yonse, chlorophylls α ndi β ndi carotenoids. Kuphatikiza apo, zomera zimavutika ndi kuwonongeka kwa PSII (kuchepa kwa ma chlorophyll fluorescence parameters monga Fv/Fm ratio) komanso kuchuluka kwa lipid peroxidation. Kumbali inayi, pamene mpunga unagwiritsidwa ntchito ndi CK ndi BR, zotsatira zoipazi zinachepetsedwa ndipo zowonjezera za proline zinawonjezeka (mkuyu 4).
Chithunzi 4. Lingaliro lachitsanzo la zotsatira za kupsinjika kwa kutentha kophatikizana ndi foliar chomera kukula kalozera utsi pa zomera mpunga. Mivi yofiira ndi yabuluu imasonyeza zotsatira zoipa kapena zabwino za kuyanjana pakati pa kutentha kwa kutentha ndi kugwiritsa ntchito foliar kwa BR (brassinosteroid) ndi CK (cytokinin) pa mayankho a thupi ndi biochemical, motsatira. gs: zilonda zam'mimba; Total Chl: okwana chlorophyll zili; Cl α: chlorophyll β zili; Cx + c: okhutira carotenoid;
Mwachidule, mayankho okhudza thupi ndi zamankhwala amuzolengedwa mu kafukufukuyu akuwonetsa kuti mbewu za mpunga za Fedearroz 2000 zimatha kutengeka ndi nthawi yovuta kwambiri ya kutentha kuposa mbewu za Fedearroz 67. Onse owongolera kukula omwe adawunikidwa mu kafukufukuyu (auxins, gibberellins, cytokinins, kapena brassinosteroids) adawonetsa kuchepetsedwa pang'ono kophatikizana kwa kutentha. Komabe, cytokinin ndi brassinosteroids zinapangitsa kusintha kwabwino kwa zomera monga momwe olamulira a kukula kwa zomera amachulukitsa chlorophyll, alpha-chlorophyll fluorescence parameters, gs ndi RWC poyerekeza ndi zomera za mpunga popanda kugwiritsa ntchito kulikonse, komanso amachepetsanso MDA ndi kutentha kwa denga. Mwachidule, timaganiza kuti kugwiritsa ntchito zowongolera kukula kwa mbewu (cytokinins ndi brassinosteroids) ndi chida chothandiza pakuwongolera zovuta mu mbewu za mpunga zomwe zimayambitsidwa ndi kupsinjika kwakukulu kwa kutentha panthawi ya kutentha kwambiri.
Zida zoyambirira zomwe zaperekedwa mu phunziroli zikuphatikizidwa ndi nkhaniyi, ndipo mafunso ena akhoza kupita kwa wolemba yemwe akugwirizana nawo.