Department of Animal and Plant Biology, Universidade Estadual de Londrina (UEL), Rodovia Celso Garcia Cid, km 380, CEP 86057-970, Londrina, PR, Brazil.
Center for Natural and Human Sciences, Universidade Federal do ABC (UFABC), Av. dos Estados 5001, CEP 09210-580, Santo André, SP, Brazil.
Sci Rep. 2019 Nov 22;9(1):17371. doi: 10.1038/s41598-019-54030-3.
Polymeric nanoparticles have emerged as carrier systems for molecules that release nitric oxide (NO), a free radical involved in plant stress responses. However, to date, nanoencapsulated NO donors have not been applied to plants under realistic field conditions. Here, we verified the effects of free and nanoencapsulated NO donor, S-nitroso-mercaptosuccinic acid (S-nitroso-MSA), on growth, physiological and biochemical parameters of neotropical tree seedlings kept under full sunlight in the nursery for acclimation. S-nitroso-MSA incorporation into chitosan nanoparticles partially protected the NO donor from thermal and photochemical degradation. The application of nanoencapsulated S-nitroso-MSA in the substrate favoured the growth of seedlings of Heliocarpus popayanensis, a shade-intolerant tree. In contrast, free S-nitroso-MSA or nanoparticles containing non-nitrosated mercaptosuccinic acid reduced photosynthesis and seedling growth. Seedlings of Cariniana estrellensis, a shade-tolerant tree, did not have their photosynthesis and growth affected by any formulations, despite the increase of foliar S-nitrosothiol levels mainly induced by S-nitroso-MSA-loaded nanoparticles. These results suggest that depending on the tree species, nanoencapsulated NO donors can be used to improve seedling acclimation in the nursery.
聚合物纳米粒子已成为释放一氧化氮 (NO) 的分子的载体系统，NO 是一种参与植物应激反应的自由基。然而，迄今为止，纳米封装的 NO 供体尚未在实际田间条件下应用于植物。在这里，我们验证了游离和纳米封装的 NO 供体 S-亚硝基巯基琥珀酸（S-nitroso-MSA）对在苗圃中全光照下进行驯化的新热带树种幼苗的生长、生理和生化参数的影响。将 S-nitroso-MSA 掺入壳聚糖纳米粒子中部分保护了 NO 供体免受热和光化学降解。纳米封装的 S-nitroso-MSA 在基质中的应用有利于不耐荫树种 Heliocarpus popayanensis 幼苗的生长。相比之下，游离的 S-nitroso-MSA 或含有未亚硝基化巯基琥珀酸的纳米粒子会降低光合作用和幼苗生长。耐荫树种 Cariniana estrellensis 的幼苗不受任何制剂的光合作用和生长影响，尽管主要由负载 S-nitroso-MSA 的纳米粒子诱导的叶片 S-亚硝基硫醇水平增加。这些结果表明，根据树种的不同，纳米封装的 NO 供体可用于改善苗圃中的幼苗驯化。
