Terrestrial plants are constantly exposed to multiple environmental signals that influence their metabolism. Among these signals, nitrogen (N) nutrition and light affect importantly diverse metabolic and physiological processes. Herewith the effects of N nutrition (8.47, 12.71 and 16.94 mg · L⁻¹ N) and shading percentages (0 and 70%) on plant morphology and chemical composition of the essential oil of marigold (Tagetes erecta L.) ‘Inca’ were assessed. Increasing N levels enhanced the number of secondary branches and the flower diameter, while shading reduced height of side branches, number of primary branches and opened flower buds. In leaves, flowers and stems, 15 different compounds were identified. In leaves, low and medium N levels and high light level increased the synthesis of ocimene, limonene and piperitone. As well, medium and high N doses, independently of the light level, stimulated the synthesis of caryophyllene and β-phellandrene in leaves. Nevertheless, increasing N doses and shading level decreased the synthesis of β-myrcene and α-pinene in leaves. In flowers, medium N level and high light intensity increased the synthesis of trans-pinene. Piperitone and verbenone were identified only in flowers of plants with high N doses and lower light intensity. In the stems, caryophyllene, piperitone and β-farnesene were more abundant with medium and high N levels. The interaction of study factors differentially affected both morphological variables and the composition of essential oil among organs studied. Therefore, N nutrition and light intensity are key factors that modify the morphology and composition of the essential oil in T. erecta.

中文翻译：

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氮素供应和遮荫影响万寿菊（Tagetes erecta L.）精油的形态和组成

陆生植物不断暴露于多种影响其新陈代谢的环境信号中。在这些信号中，氮（N）的营养和光会严重影响各种代谢和生理过程。氮素营养（8.47、12.71和16.94 mg·L ^-1 N）和遮光百分比（0和70％）对万寿菊（万寿菊）精油的植物形态和化学组成的影响L.）对“印加人”进行了评估。氮含量的增加增加了次枝的数量和花的直径，而遮荫则降低了侧枝的高度，主要枝的数量和开放的花蕾。在叶，花和茎中，鉴定出15种不同的化合物。在叶片中，低和中氮水平和高光照水平提高了奥西美，柠檬烯和哌啶酮的合成。同样，中等和高剂量的氮，与光照水平无关，也刺激了叶片中石竹烯和β-水芹烯的合成。然而，增加氮剂量和遮光水平会降低叶片中β-月桂烯和α-pine烯的合成。在花中，中等氮水平和高光照强度增加了反式的合成-pine烯 仅在高N剂量和较低光强度的植物的花中鉴定出哌啶酮和马鞭草酮。茎中的石竹烯，哌啶酮和β-法呢烯含量较高，氮含量较高。研究因素之间的相互作用差异地影响了所研究器官之间的形态学变量和精油成分。因此，氮的营养和光照强度是改变直立植物精油形态和组成的关键因素。