Soybean cultivar selection for Bioregenerative Life Support Systems (BLSS) – Theoretical selection

The development of plant-based Bioregenerative Life Support Systems (BLSS) is a requirement for the realization of long-duration exploratory-class manned missions in so far as they help fulfilling astronauts’ needs including nutritional demands, air regeneration and psychological support.The program ESA – MELiSSA (European Space Agency – Micro-Ecological Life Support System Alternative) aims to conceive an artificial bioregenerative ecosystem based on both microorganisms and higher plants. Soybean is one of the four crops studied within this program as a candidate for cultivation in forthcoming BLSS.Within this project, the aim of this study was to develop a methodology for the selection of soybean candidate cultivars for BLSS. Our scope was to identify an objective and repeatable procedure to choose the best cultivar at each time, overcoming the variability of the market supply. This purpose was pursued with an approach based on a two-steps procedure: (a) the development of an objective criterion for the selection of the most suitable soybean cultivars (cultivated varieties) based on theoretical considerations and (b) the behaviour evaluation of the 4 best cultivars with a cultivation trial in a controlled environment.In this paper, we report the first phase of the selection procedure. We started with a literature survey to look for data about environmental needs, potential yields and nutritional traits of soybean cultivars already tested in cultivation trials (disregarding Gene Modified Organisms). Afterwards, a preliminary screening based on information about the main European companies and the most commercialized cultivars, as well as on the criteria suggested by ESA, allowed to select 93 cultivars among the 297 admitted in EU. Finally, an algorithm, based on the relevance of each considered characteristic, was created to attribute a score to each cultivar and to rank it for the identification of the best cultivars for subsequent cultivation trials.