Enhancing growth and leaf yield in Gynandropsis gynandra (L.) Briq. (Cleomaceae) using agronomic practices to accelerate crop domestication

Gynandropsis gynandra (Spider plant) is an African leafy vegetable with several nutritional benefits, considered as a weed or cultivated crop. The species is of interest for local communities though knowledge on agronomic practices need to be improved. This study assessed the effects of two seedling ages at transplanting (two weeks and three weeks after sowing), three planting densities (444,444; 250,000 and 166,666 plants ha−1), three second harvest timings (one week, two weeks and three weeks after the first harvest) and three cutting heights (≤10 cm; between 10 and 15 cm and ≥15 cm) on growth and yield in Gynandropsis gynandra. The results revealed that two weeks and three weeks old seedlings could be used for the species cultivation. Seedling age, planting density and consecutive cutting time had significant effects on growth and biomass yield. Increasing planting density decreased plant growth but increased edible biomass yield. Planting density of 444,444 plants ha−1 gave the highest biomass yield (29 t ha−1). Cutting height greater than 15 cm favored a better regrowth and higher biomass yield. Harvesting plants two weeks after the first harvest gave more biomass yield but yield decreased from the first harvest to the second one. These results offer new insights into horticultural practices and the expanding of spider plant cultivation in urban and periurban areas

Understanding Molecular Mechanisms of Seed Dormancy for Improved Germination in Traditional Leafy Vegetables: An Overview

Loss of seed viability, poor and delayed germination, and inaccessibility to high-quality seeds are key bottlenecks limiting all-year-round production of African traditional leafy vegetables (TLVs). Poor quality seeds are the result of several factors including harvest time, storage, and conservation conditions, and seed dormancy. While other factors can be easily controlled, breaking seed dormancy requires thorough knowledge of the seed intrinsic nature and physiology. Here, we synthesized the scattered knowledge on seed dormancy constraints in TLVs, highlighted seed dormancy regulation factors, and developed a conceptual approach for molecular genetic analysis of seed dormancy in TLVs. Several hormones, proteins, changes in chromatin structures, ribosomes, and quantitative trait loci (QTL) are involved in seed dormancy regulation. However, the bulk of knowledge was based on cereals and Arabidopsis and there is little awareness about seed dormancy facts and mechanisms in TLVs. To successfully decipher seed dormancy in TLVs, we used Gynandropsis gynandra to illustrate possible research avenues and highlighted the potential of this species as a model plant for seed dormancy analysis. This will serve as a guideline to provide prospective producers with high-quality seeds

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