Adaptive responses to progressive drought stress in two poplar species originating from different altitudes

Abstract

Cuttings of Populus kangdingensis C. Wang et Tung and Populus cathayana Rehder, originating from high and low altitudes in the eastern Himalaya, respectively, were examined during one growing season in a greenhouse to determine the effects of progressive drought stress. The results manifested that the adaptive responses to progressive drought stress were different in these two species from different altitudes. Significant changes in stem height, leaf development, relative water content (RWC), malondialdehyde (MDA) and hydrogen peroxide (H 2 O 2 ) appeared earlier in P. cathayana than in P. kangdingensis, whereas changes in soluble protein, soluble sugar, free proline and antioxidant enzymes appeared earlier in P. kangdingensis. In addition, changes in these parameters became more and more significant when the drought stress progressed, especially under severe drought stress in P. cathayana. Plant growth showed significant positive correlations with soluble proteins and sugars, free proline and antioxidants and a significant negative correlation with RWC under water stressed treatment in two poplar species. Compared with P. cathayana, P. kangdingensis was able to maintain a superior height growth and leaf development under drought stress. Also, P. kangdingensis possessed greater increments in soluble protein, soluble sugar, free proline and antioxidant enzymes, but lower increments in MDA and H 2 O 2 than did P. cathayana when the cuttings were exposed to progressive drought stress. Our results suggest that P. kangdingensis originating from the high altitude has a better drought tolerance than does P. cathayana originating from the low altitude. Furthermore, this study manifested that acclimation to drought stress are related the rapidity, severity, duration of the drought event and the altitude of two poplar species.

ADAPTABILITY OF WHITE JABON (Anthocephalus cadamba MIQ.) SEEDLING FROM 12 POPULATIONS TO DROUGHT AND WATERLOGGING

“…Similar results of drought responses on the growth characteristics have been reported in several previous studies (Yang and Miao, 2010;Ky-Dembele et al, 2010). Water deficits reduce the number of leaves per plant, and individual leaf size, and leaf longevity by decreasing the soil's water potential.…”

Influence of Drought and Wounding Stress on Soluble Phenols and Proteins in Potato Tubers

“…Above all proline is known to protect plants against low water potentials and/or drying and is seen as a stress-related signal. For example, changes in proline became significant in Saccharum spontaneum (Munawarti et al, 2013) and poplar when drought progressed (Yang & Miao, 2010), and proline was increased in maize and in tomato root, stem and leaf as a result of drought stress (Ghorbanli et al, 2011), a tendency that was similarly noticed in drought stressed potato plants (Farhad et al, 2011). In agreement with these findings, all potato genotypes tested in this work had higher concentrations of proline in drought stressed tubers than in control tubers grown with sufficient water supply (Table 4).…”

Niveles de humedad en el suelo sobre la producción de bulbos de cebolla.

“…El déficit hídrico es uno de los factores de estrés más significativos que limita la producción de los cultivos (Lobell y Field, 2007;Reza et al, 2010), e incluso la distribución de especies maderables (Yang y Miao, 2010). Este estrés puede provocar la muerte del cultivo, además del efecto negativo en la cantidad, y calidad del rendimiento.…”