Data and R code used in: Plant geographic distribution influences chemical defenses in native and introduced Plantago lanceolata populations

Plants growing outside their native range may be confronted by new regimes of herbivory, but how this affects plant chemical defense profiles has rarely been studied. Using Plantago lanceolata as a model species, we investigated whether introduced populations show significant differences from native populations in several growth and chemical defense traits. Plantago lanceolata (ribwort plantain) is an herbaceous plant species native to Europe and Western Asia that has been introduced to numerous countries worldwide. We sampled seeds from nine native and ten introduced populations that covered a broad geographic and environmental range and performed a common garden experiment in a greenhouse, in which we infested half of the plants in each population with caterpillars of the generalist herbivore Spodoptera littoralis. We then measured size-related and resource-allocation traits as well as the levels of constitutive and induced chemical defense compounds in roots and shoots of P. lanceola..., Experimental design: Plantago lanceolata seeds were collected from nine native and ten introduced populations across a wide latitudinal and longitudinal gradient throughout the world. Sterilized seeds were then germinated in pots filled with a mixture of sand and nutrient-poor soil under greenhouse conditions in Jena, Germany. Half of the eight-week-old P. lanceolata plants were exposed to five 3rd instar S. littoralis caterpillars for 48 hours, and the other half of the plants functioned as undamaged controls (n = 5 per population, per treatment). All plants were enclosed in mesh bags that were tightened at the bottom and at the top with cable ties.
The experiment was staggered over five days, and each day a block of 38 plants (with two plants per population) was processed. To determine chemical defense traits, we first collected volatile organic compounds (VOCs) right after the herbivory treatment. After VOC collection, plant tissues (leaves, inflorescences, root crown and roots) were..., , # Data and R code used in: Plant geographic distribution influences chemical defenses in native and introduced Plantago lanceolata populations

## Description of the data and file structure

* **00_ReadMe_DescriptonVariables.csv**: A list with the description of variables from each file used.
* **00_Metadata_Coordinates.csv :** A dataset that includes the coordinates of each Plantago lanceolata population used.
* **00_Metadata_Climate.csv :** A dataset that includes coordinates, bioclimatic parameters, and the results of PCA. The dataset was created based on the script \"1_Environmental variables.qmd\"
* **00_Metadata_Individuals.csv:** A dataset that includes general information about each plant individual. Information about root traits and chemistry is missing in four samples since we lost the samples.
* **01_Datset_PlantTraits.csv:** Size-related and resource allocation traits measured of *Plantago lanceolata* and herbivore damage.
* **02_Dataset_TargetedCompounds.csv:** ...