Structural modifications for drought tolerance in stem and leaves of Cenchrus ciliaris L. ecotypes from the Cholistan Desert

Cenchrus ciliaris L. is a perennial palatable grass and is capable of growing in a variety of habitats including extreme desert environment. The present study was conducted to explore the effect of drought stress on morpho-anatomical modifications in the aerial parts of C. ciliaris ecotypes, which were collected from the Cholistan Desert. Seeds of C. ciliaris wre collected from different regions in the Cholistan desert and grown in the Faisalabad conditions. Stress treatment were applied to the ramets that were isolated from mother plants. Three moisture regimes were maintained during the experiment, i.e., 100%, 75% and 50% field capacity. Ecotypes were grouped into four categories i.e., highly tolerant, tolerant, moderately tolerant and sensitive. Highly tolerant ecotypes (E92001 and E92002) showed epidermal thickness in leaves and stem, intensive sclerification in stem, increased vascular bundle number, well developed bulliform, increased metaxylem area and decreased stomatal density on both leaf surfaces. Tolerant ecotypes (E92003 an E92008) showed dense pubescence on their leaves. It is concluded that no definite or precise single character can be taken as a yardstick for adjudging the biomass production in theses desert grass ecotypes.