Germination requirements of the extremely boron-tolerant species, Puccinellia frigida

Abstract

Puccinellia frigida is a perennial grass that is extremely tolerant to boron. It has potential to be used tophytoremediate sites with boron-toxicity, a problem that limits agriculture in regions worldwide. Moreimportantly, uncovering the genes controlling its extreme resistance would be useful to generate plants that couldbe employed to overcome boron-toxicity. To further study these subjects it is crucial to propagate P. frigida. Thisstudy aimed to determine the germination requirements of P. frigida. Germination percentage was significantlyhigher in seeds that were stored (after-ripened) longer. Temperature also affected seed germination, the optimumbeing between 16 and 20°C. Alternating temperatures also significantly improved germination. Under the bestconditions (germination at 25°C/15°C after 10 months of after-ripening), 87.5% germination was obtained. Ourresults indicate that P. frigida can be efficiently propagated through seeds, although they present a physiologicaldormancy that needs to be overcome. The results from this study will help to continue studying P. frigida inorder to increase its use for alleviating boron toxicity in soils.