Morpho-physiological responses of sugarcane crop under waterlogging condition

Abstract

The aim of this study was to investigate the effect of waterlogging on morphological and physiological traits of sugarcane variety CoC 24. Various morphological attributes were recorded under waterlogged and normal condition. Morphological parameters viz., plant height, number of internodes, number of tillers, stalk diameter, number of nodes and nodes carrying roots increasedby 18.46, 34.6, 45.65, 48.14, 3 2.14 and 52.63%, respectively, over control. The initiation of new nodal root was noted in this variety, whereas the ability to maintain root surface area by increase in longest root length and nodal root development near soil surface was also found in CoC (SC) 24. CoC (SC) 24 under flood condition at different stress periods produced more number of green leaf of 37.97%, number of dry leaf of 50% and higher growth rate than in control condition. This was possible due to the presence of constitutive aerenchyma in this variety. Hence, under stress conditions, it can easily survive by using oxygen which is preserved by aerenchyma cell, which provides a continuous system of interconnected aerial spaces of lower resistance for oxygen transport from aerial shoots to submerged roots, allowing root growth and soil exploration under anaerobic conditions. Root characters viz., number of roots, root length, root volume, root fresh and dry weight had increase over control by 64.9, 10.3, 22.07, 12.6 and 37.17%. Thus, CoC (SC) 24 variety has adventitious roots, which have high porosity, help plants to continue with water and nutrient uptake under flooding conditions, replacing in some way the functions of older root system. Under waterlogged condition, the relative water content (RWC) showedonly 1.08% increase over control condition, but water retention capacity showed 20% increase over control condition. Leaf area index and specific leaf area showed 19.04 and 41.38% decrease over control but specific leaf weight, whole plant fresh weight and dry weight had 41.49, 20.65 and 9.5% increase over control condition. The juice quality viz., brix percentage, purity percentage and pol percentage showed decrease over control condition by 4.9, 1.08 and 5.97, respectively. Yield parameters viz., single cane weight, tiller production, millable cane and cane yield were higher in CoC (SC) 24 plant crop (13.35, 3.28, 3.06 and 1.3%, respectively) under waterlogged than control condition. Based on the results, it was suggested that CoC (SC) 24 could tolerate waterlogged condition. This study also indicates that plant crops need certain post-waterlogging crop management.