Phenotypic variation in biomass and related traits among four generations advanced lines of Cleome (Gynandropsis gynandra L. (Briq.))

Gynandropsis gynandra (spider plant) is an African traditional leafy vegetable rich in minerals, vitamins and health-promoting compounds with potential for health promotion, micronutrients supplementation and income generation for stakeholders, including pharmaceutical companies. However, information on biomass productivity is limited and consequently constrains breeders’ ability to select high-yielding genotypes and end-users to make decisions on suitable cultivation and production systems. This study aimed to assess the phenotypic variability in biomass and related traits in a collection of G. gynandra advanced lines to select elite genotypes for improved cultivar development. Seventy-one advanced lines selected from accessions originating from Asia, West Africa, East Africa and Southern Africa were evaluated over two years with two replicates in a greenhouse using a 9 x 8 alpha lattice design. Significant statistical differences were observed among lines and genotype origins for all fourteen biomass and related traits. The results revealed three clusters, with each cluster dominated by lines derived from accessions from Asia (Cluster 1), West Africa (Cluster 2), and East/Southern Africa (Cluster 3). The West African and East/Southern African groups were comparable in biomass productivity and superior to the Asian group. Specifically, the West African group had a low number of long primary branches, high dry matter content and flowered early. The East/Southern African group was characterized by broad leaves, late flowering, a high number of short primary branches and medium dry matter content and was a candidate for cultivar release. The maintenance of lines’ membership to their group of origin strengthens the hypothesis of geographical signature in cleome diversity and genetic driver of the observed variation. High genetic variance, broad-sense heritability and genetic gains showed the potential to improve biomass yield and related traits. Significant and positive correlations among biomass per plant, plant height, stem diameter and leaf size showed the potential of simultaneous and direct selection for farmers’ desired traits. The present results provide insights into the diversity of spider plant genotypes for biomass productivity and represent key resources for further improvement in the species

Leaf elemental composition analysis in spider plant [Gynandropsis gynandra L. (Briq.)] differentiates three nutritional groups

Understanding the genetic variability within a plant species is paramount in implementing a successful breeding program. Spider plant (Gynandropsis gynandra) is an orphan leafy vegetable and an extraordinary source of vitamins, secondary metabolites and minerals, representing an important resource for combatting malnutrition. However, an evaluation of the leaf elemental composition, using a worldwide germplasm collection to inform breeding programs and the species valorization in human nutrition is still lacking. The present study aimed to profile the leaf elemental composition of G. gynandra and depict any potential geographical signature using a collection of 70 advanced lines derived from accessions originating from Asia and Eastern, Southern and West Africa. The collection was grown in a greenhouse using a 9 × 8 alpha lattice design with two replications in 2020 and 2021. Inductively coupled plasma–optical emission spectrometry was used to profile nine minerals contents. A significant difference (p < 0.05) was observed among the lines for all nine minerals. Microelements such as iron, zinc, copper and manganese contents ranged from 12.59–430.72, 16.98–166.58, 19.04–955.71, 5.39–25.10 mg kg−1 dry weight, respectively, while the concentrations of macroelements such as potassium, calcium, phosphorus and magnesium varied in the ranges of 9992.27–49854.23, 8252.80–33681.21, 3633.55–14216.16, 2068.03–12475.60 mg kg−1 dry weight, respectively. Significant and positive correlations were observed between iron and zinc and calcium and magnesium. Zinc, calcium, phosphorus, copper, magnesium, and manganese represented landmark elements in the genotypes. Eastern and Southern African genotypes were clustered together in group 1 with higher phosphorus, copper and zinc contents than Asian and West African lines, which clustered in group 2 and were characterized by higher calcium, magnesium and manganese contents. An additional outstanding group 3 of six genotypes was identified with high iron, zinc, magnesium, manganese and calcium contents and potential candidates for cultivar release. The genotype × year interaction variance was greater than the genotypic variance, which might translate to phenotypic plasticity in the species. Broad-sense heritability ranged from low to high and was element-specific. The present results reveal the leaf minerals diversity in spider plant and represent a baseline for implementing a minerals-based breeding program for human nutrition

Andromonoecy in Gynandropsis gynandra (L.) Briq. (Cleomaceae) and effects on fruit and seed production

Spider plant (Gynandropsis gynandra) is a traditional leafy vegetable widespread in sub-Saharan Africa and tropical Asia that is also valued for its medicinal properties. Developing a breeding program for the species requires detailed knowledge of its phenology, floral morphology and pollination system. This study investigates the effects of floral morphology and pollination mechanisms on the reproductive success in G. gynandra. The experiments were conducted in two locations in Benin. A split-plot design was used with four randomized complete blocks. Three accessions were randomly assigned to the whole plots and five treatments including natural self-pollination, hand self-pollination, geitonogamy, open pollination and hand cross-pollination were randomized over the sub-plots. We observed that individual plant exhibited 70% of staminate (male) flowers and 30% of hermaphrodite flowers. G. gynandra was andromonoecious. Open pollination and hand cross-pollination led to higher fruit and seed set. Natural self-pollination and hand self-pollination resulted in lower fruit and seed production. G. gynandra is a self-compatible and predominantly out-crossing species. Cross-pollination resulted in a significant increase in fruit set. This study set the ground for the development of improved cultivars in G. gynandra.</p

Ten years of Gynandropsis gynandra research for improvement of nutrient-rich leaf consumption : Lessons learnt and way forwards

This article reveals progress and gaps in spider plant (Gynandropsis gynandra Syn. Cleome gynandra) research to date. It synthesises the current knowledge in systematics and botany, geographical distribution, nutrient content, and health values as well as the agronomic practices related to the species. This article further presents the germplasm availability, status, and places of conservation around the world to exploit the extant genetic diversity for genomics-assisted breeding and seed systems development. It describes how various parts of the plant have been used and the potential for economical revamping and further industrial valorisation. Nutrient content and phytochemical diversity across cultivation systems and geographical ranges and known health attributes were analysed to identify gaps and bottlenecks for fostering further investigations for industrial food and drug production