Leaf anatomical adaptation under early drought stress of sugarcane cultivars – KKU-1999-02 and KKU-1999-03

Anatomical adaptation is an important feature that allows plants to mitigate drought stress. A comparative leaf anatomy of two drought-tolerant sugarcane cultivars, KKU-1999-02 and KKU-1999-03, was studied in early drought stress between 30 and 90 days after planting using peeling and freehand sectioning methods. KKU-1999-02 and KKU-1999-03 showed different anatomical adaptation features, such as increase in cuticle thickness, bulliform cell size, vascular bundle, and stomatal density, and decreases in leaf thickness and stomatal size. KKU-1999-02 showed more remarkable anatomical changes than KKU-1999-03. The results provide important information that can be applied in combination with other agronomic traits in sugarcane breeding programs to expand the adaptation devices of tolerant cultivars under preliminary drought stress

Changes in root xylem anatomy of peanut genotypes with different drought resistance levels under early-season drought

During the 2014 and 2015 seasons, peanut root anatomy studies were conducted under well-watered and under drought conditions using three peanut genotypes which are known to differ in their physiological responses to early- and mid-season drought (ICGV 98,305, ICGV 98,324 and Tifton-8). Cross sections of the newly formed roots revealed that the average vessel diameter and total vessel area in the first-order roots were significantly reduced under drought in ICGV 98,305 and ICGV 98,324, yet not in Tifton-8, which had the smallest vessel diameters and total area in both well-watered and drought treatments. The xylem vessel structure in newly formed roots of ICGV 98,324 was very responsive to changes in soil moisture content. This adaptive capacity of ICGV 98,324 to change xylem structure as soil moisture conditions change may provide plant breeders an important trait which will lead to better water-use efficiencies in both moist and drought conditions