Amasifuen Guerra Carlos A, Patel Kirti, Delprete Piero G, Spina Andréa P, Grados Juan, Vásquez-Ocmín Pedro, Gadea Alice, Rojas Rosario, Guzmán Jesús, Sauvain Michel
Laboratorio Mixto Internacional de Química de la Vida, Institut de Recherche Pour le Développement (IRD), Universidad Peruana Cayetano Heredia (UPCH), Avenida Honorio Delgado 430, Urb. Ingeniería, San Martín de Porres 34, Lima 15024, Peru.
Dirección de Recursos Genéticos y Biotecnología (DRGB), Instituto Nacional de Innovación Agraria (INIA), Avenida La Molina N° 1981, La Molina, Lima 15024, Peru.
Plants (Basel). 2022 Apr 8;11(8):1011. doi: 10.3390/plants11081011.
We explored the concentration patterns of the bioactive metabolite plumericin produced by Himatanthus tarapotensis (Apocynaceae) under different edaphic conditions and variations in rainfall intensity, as well as its potential role in the chemical defense against insect herbivores. Values of plumericin concentration from leaves were obtained by High-Performance Liquid Chromatography, and evaluated as a function of differences in soil types, variation of precipitation, and variation of the abundance of insect herbivores, using first a Repeated Measures Correlation (rmcorr) and then a Generalized Linear Mixed Model (GLMM) analysis. Plumericin concentration is highly variable among plants, but with a significantly higher concentration in plants growing on clay soil compared to that of the white-sand soil habitat (p < 0.001). Plumericin concentration is not affected by precipitation. The caterpillar of Isognathus leachii (Lepidoptera: Sphingidae) is the most conspicuous herbivore of H. tarapotensis, and its presence is continuous but not related to plumericin concentration, probably because of its capacity to elude the chemical defense of this plant. Nevertheless, our multivariate model revealed that plumericin concentration is related to the abundance of Hymenoptera (Formicidae), and this relationship is significantly influenced by the soil parameters of carbon percentage, clay percentage, and phosphorous percentage (p < 0.001). Plumericin is a mediating agent in the interaction between H. tarapotensis and its natural environment. Variation in plumericin concentration would be induced by the abundance of Hymenoptera (Formicidae), probably as a chemical response against these insects, and by differences in soil nutrient availability.
我们探究了塔拉波藤（夹竹桃科）在不同土壤条件和降雨强度变化下产生的生物活性代谢产物异翅藤素的浓度模式，以及其在抵御昆虫食草动物化学防御中的潜在作用。通过高效液相色谱法获得叶片中异翅藤素的浓度值，并将其作为土壤类型差异、降水量变化和昆虫食草动物丰度变化的函数进行评估，首先使用重复测量相关性（rmcorr）分析，然后使用广义线性混合模型（GLMM）分析。异翅藤素浓度在不同植株间差异很大，但与生长在白沙土生境的植株相比，生长在黏土上的植株中该物质浓度显著更高（p < 0.001）。异翅藤素浓度不受降水量影响。莱氏长喙天蛾（鳞翅目：天蛾科）的幼虫是塔拉波藤最显著的食草动物，其存在持续存在，但与异翅藤素浓度无关，这可能是因为它有能力避开这种植物的化学防御。然而，我们的多变量模型显示，异翅藤素浓度与膜翅目（蚁科）的丰度有关，并且这种关系受到土壤中碳百分比、黏土百分比和磷百分比等参数的显著影响（p < 0.001）。异翅藤素是塔拉波藤与其自然环境相互作用的介导因子。异翅藤素浓度的变化可能由膜翅目（蚁科）的丰度引起，这可能是对这些昆虫的一种化学响应，也可能由土壤养分有效性的差异引起。
