氧化石墨烯调控甘蓝型油菜耐旱性机制OA

To investigate the regulatory mechanism of graphene oxide(GO)on drought resistance in Brassica napus,this study utilized the cultivar Huayouza 50 as experimental material.Drought stress was applied followed by exogenous treatments with clean water(CK),15 and 25 mg/L GO.The activities of protective enzymes such as superoxide dismutase(SOD),peroxidase(POD),catalase(CAT),and ascorbate peroxidase(APX)were measured,along with the contents of osmoregulatory substances including proline(Pro)and soluble protein.Additionally,the content of malondialdehyde(MDA),and the levels of hormones such as gibberellin(GA),indole-3-acetic acid(IAA),and abscisic acid(ABA)were determined in various treatments of B.napus.Furthermore,the transcriptional levels of genes related to GA,IAA,and ABA(RGA,GA3,ARF2,and NCED)were detected using quantitative polymerase chain reaction(qPCR)technology.The results showed that the survival rate of rapeseed treated with 25 mg/L GO was significantly higher than that of the control(31.67%)under drought stress.At the physiological level,compared with CK,the activities of POD,SOD,CAT,and APX in plants were enhanced under 25 mg/L GO treatment,while the MDA content(6.82 μg/g)decreased and proline(623.51 μg/g)and soluble protein(4 939.27 μg/g)accumulated.At the molecular level,compared with CK,25 mg/L GO application upregulated the expression of GA biosynthesis gene GA3 and IAA signaling gene IAA2,while 15 mg/L GO treatment promoted the transcription of NCED,a pivotal gene in ABA synthesis.These findings suggest that GO enhances drought tolerance in B.napus by modulating hormone-related signaling pathways,thereby strengthening antioxidant defense systems and osmotic adjustment capacity.This study provides critical insights into the application of nanomaterials in improving crop stress resistance and highlights the potential of GO as a novel agrochemical agent for sustainable agriculture under abiotic stress conditions.