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Plukenetia volubilis (Euphorbiaceae) is an underutilized oilseed crop native to the Amazon basin, where it has been utilized by humans since Incan times. The large seeds contain approximately 45–50% lipid, of which approximately 35.2–50.8% is α-linolenic acid (C18:3 n-3, ω-3) and approximately 33.4–41.0% is linoleic acid (C18:2 n-6, ω-6), the two essential fatty acids required by humans. The seeds also contain 22–30% protein and have antioxidant properties. Due to its excellent nutritional composition and good agronomic properties, it has attracted increasing attention in recent years, and cultivation is expanding. When considering current global challenges, a reformation of our food systems is imperative in order to ensure food security, mitigation of climate change, and alleviation of malnutrition. For this purpose, underutilized crops may be essential tools which can provide agricultural hardiness, a reduced need for external inputs, climate resilience, diet diversi-fication, and improved income opportunities for smallholders. Plukenetia volubilis is a promising up and coming crop in this regard and has considerable potential for further domestication; it has an exceptional oil composition, good sensory acceptability, is well suited for cultivation, and has numerous potential applications in, e.g., gastronomy, medicine, and cosmetics.

Underutilized crop species have the potential to aid in alleviating some of the challenges faced by the world today; reduced food security and malnutrition, land degradation, and climate change. The incorporation of little-known crops into sustainable agricultural systems provides new developmental opportunities and can increase the resilience of food production systems. However, measures need to be taken to address issues of variation in product quality and access to propagation material. Plukenetia volubilis L. (Euphorbiaceae) is an oleaginous liana native to the Amazon basin. It is of growing economic importance in the food, pharmaceutic, cosmetic and horticultural industries, however, commercial cultivars are lacking and the genetic variation within the species is very high. Furthermore, the majority of landraces of P. volubilis are susceptible to nematodes. In order to attain plants with a consistent quality and yield, vegetative propagation schemes are beneficial. Grafting is an especially favourable technique which enables the selection of pest and disease resistant rootstocks in combination with high-yielding or ornamentally valuable scions. Three different grafting techniques combined with three different systems of protection were tested on P. volubilis and evaluated according to the growth of the scions following grafting. The experiment was carried out under nursery conditions in the San Martı´n region of Peru, where P. volubilis is commonly cultivated. Regardless of the grafting technique, a 100% survival rate was found for plants covered with a plastic bag following grafting. This result may aid in the further domestication of P. volubilis by providing farmers with access to plant material of consistent quality and allowing the selection of pest resistant rootstocks in combination with high-yielding scions.

Plant transformation with the wild type Ri plasmid T-DNA of Agrobacterium rhizogenes is a promising method for breeding of compact plants and has been the subject of numerous studies. However, knowledge concerning the isolated functions of single genes and ORFs from the plasmid is limited. The rolB and ORF13 oncogenes of A. rhizogenes show considerable promise in plant breeding, but have not been comprehensively studied. Detailed information regarding the morphological impact of specific genes of the Ri plasmid will allow for optimized targeted breeding of plants transformed with the wild type Ri plasmid T-DNA. rolB and ORF13 were recombined into the genome of Arabidopsis thaliana using Gateway(®) cloning and the effect on plant growth was assessed biometrically throughout the plants' life cycle. rolB-lines exhibited dwarfing, early necrosis of rosette leaves, altered leaf and flower morphology, and developed an increased number of inflorescences per rosette area compared to the wild type. ORF13-lines were extremely dwarfed, attaining only ca. 1% of the rosette area of the wild type, leaf and flower size was reduced, and the shape modified. The study documents that the traits inferred by the rolB oncogene yield plants with increased formation of generative shoots, but also result in some degree of premature senescence of vegetative organs. The extreme dwarfism seen in ORF13-lines indicate that this oncogene may be more important in the dwarfing response of plants transformed with the wild type Ri plasmid T-DNA than previously assumed and that transformation with this oncogene induces a very compact phenotype.