Location: Plant Genetic Resources Unit (PGRU)
Project Number: 8060-21000-027-008-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Jul 1, 2019
End Date: Jun 30, 2022
The demand for safe, fresh and diversified baby greens has generated significant new opportunities, including the production for 'Go Local' markets and the developing controlled-environment agriculture (CEA)/vertical production systems. The non-heading leafy accessions within Brassica oleracea and the Cucurbitaceae are central to the diversification and the advancement of these markets. Baby green production is currently dominated by lettuce, spinach and arugula crops, but new markets are now being driven by products such as baby 'lacinato' kale that are perceived as nutritious and versatile, Leading to the development of diverse value-added markets across production systems. The development of new markets is constrained as Brassica varieties typically have high seed costs making them inefficient in systems that seed 4.5-6 million seeds/acre. This project will screen the non-heading Brassica oleracea accessions in the NE9 collection to identify and advance Brassica genotypes that would be appropriate for baby green production and vertical farming based on their quality, mating system and seed production characteristics. Brassica accessions suitable for baby green production will be focused on types that are conducive to low seed cost (annual, self-compatible and high seed set), high uniformity, high vigor and consumer acceptability. This effort will lead to the identification of Brassica accessions suitable as baby greens across production systems. This will support several areas of U.S. agriculture including the quickly expanding areas of local production, fresh greens and vertical farming systems. Currently vertical farming systems are primarily focused on mainstream leafy green markets such as lettuce and spinach that have low cost seed supplies but are competing against established industries. While some higher value niche markets exist for crops such as basil and chard these can quickly be saturated. The identification of Brassica accessions that would be appropriate for these systems will be based on seedling vigor, uniformity and quality; however, to be a viable candidate low cost seed production is essential. This effort proposes evaluation of the accessions within the NE9 collection against checks to determine those that can be viable candidates as new baby green varieties based on seed production metrics and traits important for baby green production. By preserving these cucurbit species, food system biodiversity decline can be reduced as well as malnutrition and food security in the US by introducing international crops that are naturally pest and disease resistant.
The Brassica oleracea accessions that will be appropriate for baby green markets can be categorized as multiple subspecies such as 'viridis', 'acephala' and 'costa' that is not always consistent. These fall loosely under the category of 'kale', for which there are 113 accessions listed as available in the NE9 collection, 51 of which are collard or 'viridis'. There are at least an additional 95 listed as active 'G' accessions, if funded I would work with the curator Dr. Joanne Labbate to determine what percentage of these would be available for screening. It is anticipated that the initial screen will be of approximately 200 accessions. These will be grown out in May-June 2019 and evaluated against 20 baby green checks from within the crucifer family (kale, Russian kale, Chinese kale, rapa kale, mustard, arugula). This will be to eliminate any accessions that clearly would not be appropriate as baby green varieties based on vigor, appearance and type. It is anticipated that over 100 accessions will be advanced to the field screening component of this effort.  Leafy Brassica genotypes will be evaluated for their potential as baby greens based on different seed production characteristics due to the high seed number required. These characteristics include an annual life cycle, self-compatibility, high seed production and desirable leaf and consumer traits. The USDA NE9 accessions identified in objective '1' will be planted on raised plastic beds in Freeville NY with 8 plants/accession comprising approximately 1000 plants total. These will be planted at 0.5m separation for evaluation and grown through to maturity in September 2019 to determine the annual types. Having previously screened the collard collection in 2009, it is known that a high number of the accessions will flower in the field (approximately half) with no or minimal cold acclimation. The accessions will be evaluated for vigor and type including digitally imaging the accessions.  The accessions that break into flowering will be scored and two representative plants of each of those accessions will be removed from the field and transplanted into 10" pots. They will then be grown through to flowering in greenhouses in Geneva NY. Flowers will be brushed twice weekly to simulate wind and insect activity to determine seed set potential. Self- incompatible accessions will not be appropriate for the high seed numbers needed for Brassica baby greens, this effort will be to identify the non-heading Brassica accessions that are self- compatible, and have the ability to generate high seed numbers. Additional scoring of these accessions will be made to determine the accessions that have a high degree of self- incompatibility that would have potential as a seed parent for hybrid varieties.  Accessions from each USDA GRIN exotic Cucurbitaceae collection will be chosen, working with each curator to identify a cross section of the available biodiversity. These will include ~72 accessions requiring seed rescue, that capture important biodiversity within Cucurbitaceae. Seed rescue will occur via single seed increases in the greenhouse winter season.