Abstract
BackgroundCotyledon micrografting represents a useful tool for studying the central role of cotyledons during early plant development, especially their interplay with other plant organs with regard to long distance transport. While hypocotyl micrografting methods are well-established, cotyledon micrografting is still inefficient. By optimizing cotyledon micrografting, we aim for higher success rates and increased throughput in the model species Arabidopsis thaliana.ResultsWe established a cut and paste cotyledon surgery procedure on a flat and solid but moist surface which improved handling of small seedlings. By applying a specific cutting and joining pattern, throughput was increased up to 40 seedlings per hour. The combination of short-day photoperiods and low light intensities for germination and long days plus high light intensities, elevated temperature and vertical plate positioning after grafting significantly increased ‘ligation’ efficiency. In particular high temperatures affected success rates favorably. Altogether, we achieved up to 92% grafting success in A. thaliana. Reconnection of vasculature was demonstrated by transport of a vasculature-specific dye across the grafting site. Phloem and xylem reconnection were completed 3–4 and 4–6 days after grafting, respectively, in a temperature-dependent manner. We observed that plants with grafted cotyledons match plants with intact cotyledons in biomass production and rosette development.ConclusionsThis cut and paste cotyledon-to-petiole micrografting protocol simplifies the handling of plant seedlings in surgery, increases the number of grafted plants per hour and greatly improves success rates for A. thaliana seedlings. The developed cotyledon micrografting method is also suitable for other plant species of comparable size.
Highlights
Cotyledon micrografting represents a useful tool for studying the central role of cotyledons during early plant development, especially their interplay with other plant organs with regard to long distance transport
We developed cut and paste cot-grafting performed on a flat solid surface based on the general conditions for hypocotyl micrografting [22]
Having achieved success rates over 90% in hypocotyl micrografting, we developed a new cutting and joining approach for cotyledon micrografting (Figs. 1, 2a) and analyzed different combinations of conditions before and after grafting and their respective success rates (Table 1)
Summary
Cotyledon micrografting represents a useful tool for studying the central role of cotyledons during early plant development, especially their interplay with other plant organs with regard to long distance transport. Bartusch et al Plant Methods (2020) 16:12 success rates of up to 87% [20] and 100% [21, 22], respectively, cotyledon micrografting (cot-grafting) success rates have been very low so far (< 2% [13]) Despite this constraint, cot-grafting was already successfully applied to reveal the important role of cotyledons in floral development [13, 23]. The role of cotyledons in plant development and their interaction with other plant organs is of great importance [24,25,26], cot-grafting has not been utilized for other approaches probably because of the low success rate as illustrated by the only described method so far [13]. This may be one of the main reasons for the low success rate
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
