Foliar carbon dot amendment modulates carbohydrate metabolism, rhizospheric properties and drought tolerance in maize seedling
Foliar carbon dot amendment modulates carbohydrate metabolism, rhizospheric properties and drought tolerance in maize seedling
复制标题
叶面碳点改良剂调节玉米幼苗的碳水化合物代谢、根际特性和耐旱性
DOI：
10.1016/j.scitotenv.2021.151105
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发表时间：
2022
影响因子：
9.8
通讯作者：
Baoshan Xing
中科院分区：
文献类型：
--
作者：
Hanyue Yang;Chuanxi Wang;Feiran Chen;Le Yue;Xuesong Cao;Jing Li;Xiaoli Zhao;Fengchang Wu;Zhenyu Wang;Baoshan Xing
由于粮食安全和人口增长，提高玉米耐旱性对于扩大生产非常重要。以柠檬酸和乙二胺为碳源，采用水热法合成了碳量子点。然后，将CD（5 ml，5 mg·mL-1）喷洒在第25天龄的玉米（Zea maysL.，干旱胁迫，35%土壤水分）连续7天（喷洒超纯水作为对照），之后评估干旱下玉米的生理参数和根际特性。叶面喷洒CD（5 mg·mL-1）可以增加根系分泌物（例如，琥珀酸（14.5倍）、甜菜碱（11.8倍）和甜菜碱（10.0倍））和修饰微生物群落。其中假单胞菌、鞘氨醇单胞菌、硝化螺旋菌和锥壳菌的相对丰度分别增加了344.4%、233.3%、126.2%和122.6%。改变微生物丰度可使土壤有效氮和有效磷分别增加33.5%和16.8%，使植物吸水量增加37.2%。叶面喷施CD后，叶片净光合速率和碳水化合物含量分别增加了122.9%和35.4%，根系碳水化合物含量增加了113.6%，从而导致了分泌物合成和微生物丰度的变化。地上部和地下部鲜重分别增加62.1%和50.6%，地上部和地下部干重分别增加29.2%和37.5%。这些结果表明，叶面喷施CD可以改善玉米根际环境，提高玉米的耐旱性，促进玉米的生长。因此，叶面施用CD将是应对干旱胁迫的可持续纳米农业的一个有前途的策略。
Improving maize drought tolerance is of great importance for scaling up production due to food security and population growth. Carbon dots (CDs) were synthesized by hydrothermal method with citric acid and ethylenediamine as carbon sources. Then, CDs (5 ml, 5 mg‧L−1) were sprayed on 25th day-old maize (Zea maysL., drought-stress, 35% soil moisture) for seven consecutive days (spraying ultra-pure water as control), after which the physiological parameters and rhizospheric properties of maize under drought were evaluated. Foliar sprayed CDs (5 mg‧L−1) could increase root exudates (e.g., succinic acid (14.5 folds), pyruvic acid (10.0 folds), and betaine (11.8 folds)), and modify microbial community. Particularly, the relative abundance ofPseudomonas,Sphingomonas,Nitrospira, andConocybewere significantly increased by 344.4%, 233.3%, 126.2%, and 122.6%, respectively. The altered microbial abundance could improve soil available nitrogen and phosphorus by 33.5% and 16.8%, respectively, and increase plant water uptake by 37.2%. The change of exudate synthesis and microbial abundance could be driven by the significantly increased in net photosynthesis rate by 122.9%, and carbohydrate content by 35.4% in shoots and 113.6% in roots, respectively upon foliar application of CDs. Meanwhile, fresh weight of shoots and roots were increased by 62.1% and 50.6%, and dry weight of shoots and roots were increased by 29.2% and 37.5%, respectively. These results demonstrated that foliar application of CDs could improve the rhizosphere environment to enhance maize drought tolerance and even growth. Therefore, foliar application of CDs would be a promising strategy for sustainable nano-agriculture in response to drought stress.