Assessment of drought stress reaction during sensitive growth stages of common winter wheat cultivars applying remote and physiological methods

Radoslav Chipilski, Petar Petrov, Konstantina Kocheva, Georgi Georgiev

Abstract: Four cultivars of well watered common winter wheat were grown as small plots with random design under rain-out shelter to full maturity. Part plots were non-irrigated for 15 days during heading growth stage followed by re-watering to the end of growth. The aim of the research was to evaluate drought tolerance during sensitive growth stage of heat by application of remote and destructive methods of analysis. Remote indexes were canopy temperature depression (CTD) and leaf chlorophyll index (CCI). Laboratory methods were flag leaf relative water content (RWC) and transpiration rate (TR). Leaf anatomy was studied by light microscopy method. Leaf architecture and anatomy correlate with the changes of remote and lab physiological indexes. Cultivars with erected flag leaf distribution showed less reduced water status and yield after controlled drought stress during heading stage. These results correlated with remote measured parameters CTD and CCI. The dependence between indexes can be used for modeling growth reaction of cultivars under moderate drought stress.

Keywords: canopy temperature depression; chlorophyll index; drought stress; flag leaf; water status; wheat

Date published: 2019-05-27