UV-B 輻射脅迫下水稻旗葉氮代謝的代際響應特征

中圖分類號：S511 文獻標志碼：A 文章編號：2095-6819（2025）05-1335-07 doi：10.13254/j.jare.2024.0541

Transgenerational response characteristics of nitrogen metabolism in flag leaves of rice under UV-B radiationstress

ZHANGLei1，WANGXiupin2，LIZuran3，HEYongmei1，LIYuan1

（1.ColegeofesorcdEviont，YngicuralUiversitKuinga;.olgofiald Technology，YuanAgriculturalUversityumin6Oia;3.olgeofriclturendLndscape，Yuaniculual University，Kunming650201，China）

Abstract：InodertexploeetasgeneratioalesposecharacterstiofrogenmetabolsinflagleavesofieOryastiL）in Yuanyang Terraced fields to UV-B radiation stress，a field experiment was conducted to simulate 7.5kJ?m^-2 UV-B radiation on the land surface.Rice seeds irradiated by 7.5kJ?m^-2 UV-B for 0 ， 1，2 and3 years were planted in situ under natural light and 7.5 kJ?m^-2 UV-B radiation.AoneyearfieldexperimentwasconductedtostudytheefectsofdiferentgeneratiosofUV-Bradiationwiththesameintesity onnitrogenmetabolism-relatednzesandnitrogencontainingcompoundsinflagleavesofYuanyangeracedrice（BaijiaoLaojing）. TheresultsshowedthatunderthesaeintensityofUV-Badiationstres，whenthadiationmemoryandlivingenviromentfiewere matched，theratetrog（NO-）onentofgleafinFgeatiossigicantlycreasedby9.5%omparedwiatF1 generation，and the glutamine synthetase（GS）and glutamate dehydrogenase（GDH） in the same generation were 157.2% and 24.0% higher thanthoseinFgeneratin，espctivelyhichprootedteproessofmonassilationiceleavs.Tetetfo nitrogen（NH4-N）wassignificantlylowerthanthatofF1generation.TheNO-NcontentoflagleafinF3generationwassigniicantly higher than thatin F1 generation by 75.3% ，and the total free amino acid content in the same generation was higher than that in F1 generation by 38.4% .The nitrogen metabolism of F3 generation rice began to produce transgenerational adaptive changes，which had resistancetoUV-BradiationstressUnderthesameintensityofUV-Bradiationstresswhentheradiationmemoryandlivingeviont ofdiferentgeratsofcidtatchctiviyfgafucaediteviottotalfrodt decreasedsignificantlyndteitrognmetabolismassillibiedbyUV-BdiationRiceplantsdidotdeveloptoleranctUV-B radiationstress.Insummary，underUV-Bradiationstress，theflagleafnitrogenmetabolismofYuanyang Terrcedricehas transgenerationalplasticity，whichpromotesadaptivechangesinnitrogenmetabolismbyregulatingtekeyezyes（GSandGDH）nd nitrogen-containing compounds in nitrogen metabolism of different generations of rice.

Keywords：UV-B radiation; nitrogenmetabolism; flag leaf of rice; transgenerational plasticity; Yuanyang Terrace

中波紫外線UV-B（280～315nm）是太陽光的一部分，對作物的生理代謝和生產力都具有破壞性影響，已成為制約農作物生長的一類環境脅迫因子。氮代謝作為植株最重要的代謝之一，調控著水稻（OryzasativaL.）的生長發育過程，是影響水稻生產力的決定因素[1-2]。氮代謝是一個復雜的生理過程，包括氮素的吸收、同化、損失和再利用，是無機氮（硝態氮和銨態氮）同化和有機氮合成轉化的過程3。UV-B輻射增強會直接影響水稻的氮代謝相關酶（硝酸還原酶、谷氨酸合成酶、谷氨酰胺合成酶和谷氨酸脫氫酶）和氮代謝產物（氨基酸、蛋白質）含量來影響植株氮代謝，從而影響植株生長發育和繁殖等行為，造成稻田生產力降低[4-。

水稻可以通過改變植株的形態結構與生理代謝過程，促進植株發生適應性變化以響應UV-B輻射脅迫[7-1]。近年來研究發現，表觀遺傳在水稻抵抗環境脅迫（鹽堿、干旱、重金屬、紫外輻射等）的過程中發揮了重要作用。表觀遺傳修飾解釋了短期內（當代）植物通過調整表型以響應環境脅迫的現象[11]。這種環境誘導植物產生的適應性變化不僅發生在世代內，還能夠傳遞給子代，影響子代的生長發育與生理代謝等過程[12-16]，稱為“代際記憶\"7]。子代繼承這種“代際記憶\"的現象即為代際可塑性[8]。目前，研究人員已經發現植物形態、生理代謝具有代際可塑性，且當子代生存環境與母本生存環境匹配時，子代能夠繼承母本的脅迫記憶以適應脅迫環境，且能夠穩定遺傳多個世代。……