中文摘要：

研究了平邑甜茶幼苗生长过程中根、茎、叶和子叶精氨酸、精氨酸酶、一氧化氮（NO）、一氧化氮合酶（NOS）水平的变化及其与幼苗生长发育的关系。结果表明,精氨酸含量和精氨酸酶活性子叶中最高,且随幼苗生长发育逐渐下降,其次为叶片和茎,根中最低。幼苗生长第5 d的子叶中NO含量及NOS活性均最高,此后迅速下降至较低水平。除子叶外,NO含量和NOS活性在茎中较高,生长第11 d均达到最高,与茎的快速生长相适应;叶片居中,在第17 d达到高峰,与叶片的快速生长有关;根中最低,在第8 d达到最高,与主根的快速生长相对应。这些结果表明,NO在快速生长的器官中含量高,可能与平邑甜茶幼苗各器官的生长发育有关;而子叶中的精氨酸可能是平邑甜茶幼苗早期生长主要的氮素贮藏营养物质之一。

英文摘要：

Changes in arginine, arginase, nitric oxide （NO）, nitric oxide synthase （NOS）levels in roots, stems, leaves and cotyledons of Malus hupehensis Rehd. seedlings, which are related to plant growth and development, were investigated. The results showed that the levels of arginine and arginase were the highest in cotyledons, which decreased slowly during plant development, followed by leaves and stems, with roots being the lowest. In cotyledons, NO and NOS levels reached the highest after 5 days of growth, then decreased quickly after 8 days of growth. Among roots, stems and leaves, the highest levels of NO and NOS existed in stems and reached the highest after 11 days of growth, coinciding with the rapid elongation of stems, while those of roots were the lowest and reached the highest after 8 days of growth, coinciding with the rapid elongation of primary roots. NO and NOS levels in leaves reached the highest after 17 days of growth, coinciding with the rapid expansion of leaves. It is concluded that NO is mainly located in actively growing tissues, suggesting its possible roles in plant growth and development in Malus hupehensis Rehd. seedlings and cotyledon arginine might be one of the important nitrogen reserve that is required for the early development of the seedlings.