Crocus sativus L. response to flooding: enzymatic activities in flooded corms and post-flooding survival

Extensive flooding resulting from recent climate changes stresses the urgency to investigate plants ability to survive hypoxia/anoxia intervals. Crocus sativus L., cultivated as the source of saffron, is propagated only by its corms.
These are plant organs primarily exposed to flooding and it is critical to investigate their resilience.
Access to fermentable sugars being crucial for survival under low-oxygen conditions, amylases activity, maltose content, and lignin peroxidase activity were studied in flooded C. sativus corms.
Post-flooding survival was monitored.
Dormant and sprouting corms were flooded in vitro for up to 14 days, then returned to normoxia.
Controls were cultivated in normoxia.
Enzymatic activities and maltose content were measured in extracts from control and flooded corms, at timed intervals during hypoxia/anoxia.
Root and shoot elongation were measured throughout the study.
Flooded dormant corms did not sprout.
They exhibited decreases in α- and β-amylase activities (respectively 90 and 75%), increase in maltose content (40%), and decrease in lignin peroxidase activity (50%). Flooded sprouting corms interrupted root and shoot growth.
They exhibited decreases in α- and β-amylase activities (respectively 50 and 75%), decrease in maltose content (60%), and a transient increase in lignin peroxidase activity (50%). Upon return to normoxia, dormant corms flooded for up to 10 days initiated root and shoot growth.
Sprouting corms flooded for up to 14 days resumed shoot elongation.
Root number and shoot elongation rate were significantly reduced compared to control corms.
No flowering was observed but new corms were generated, insuring propagation and survival.
The present experiment showed that a quiescence strategy with minimum starch reserves utilization assisted the plant to survive prolonged flooding intervals.

IV International Symposium on Horticulture in Europe – SHE2021

J. Keyhani, E. Keyhani

amylases, lignin peroxidase, maltose, saffron, hypoxia/anoxia, roots, shoots

https://doi.org/10.17660/ActaHortic.2021.1327.81