Ahmed, S., Nawata, E., Hosokawa, M., Domae, Y., Sakuratani, T. (2002) Alterations in photosynthesis and some antioxidant enzymatic activities of mungbean/subjected to waterlogging, Plant Sci. 163 , 117
Authors:P. Zaidi, P. Maniselvan, R. Sultana, M. Yadav, R. Singh, S. Singh, S. Dass, and G. Srinivasan
Selection on the basis of grain yield
for improved performance under excessive moisture stress has often been misleading and considered inefficient. We assessed the importance of secondary traits of adaptive value under waterlogging stress. During the 2000–2004 summer-rainy seasons twelve trials were conducted and a total of 436 tropical/subtropical inbred lines (S
) were evaluated under excessive soil moisture stress. Excessive moisture treatment was applied at V
growth stage by flooding the experimental plots continuously for seven days. Different phenological and physiological parameters were recorded before, during and either immediately or 1–2 weeks after exposure to stress. Excessive moisture conditions significantly affected all the morphological and physiological traits studied. However, there was significant genetic variability for various traits, especially for root porosity and brace root development that were induced under excessive moisture. Across the trials, significant genetic correlations (p<0.01) was obtained between grain yield and different secondary traits, including ears per plant, root porosity, brace root fresh weight, number of nodes with brace roots and anthesis silking interval. Broad-sense heritability decreased under excessive moisture stress conditions for most of the traits; however, it increased significantly for root porosity, nodal root development and ears per plant. Our findings suggest that consideration of these second-ary traits during selection of maize germplasm for excessive moisture tolerance can improve selection efficiency and genetic gains.
Water is a distinguished stress factor of soils and ecosystems. The description and analysis of positive or negative soil-water stresses are the preconditions of the efficient control of their mechanisms, reversible and/or irreversible consequences. The most significant soil-water stress is extreme moisture regime: water surplus (flood, water-logging, over-moistening) or water deficiency (drought). Their main reasons are the irregular atmospheric precipitation; limited water infiltration into and storage within the soil; high evaporation, surface runoff and filtration losses. In addition to the direct impacts the consequences are the changes in the mass and energy regime of soils and in their biogeochemical cycles. The possibilities of the control of soil-water stress are: help infiltration, storage and availability of soil water; improve the plants’ water uptake; irrigation and drainage.
hydrogeologically closed Carpathian Basin
particular importance in the salinization/alkalization processes. In the
poorly-drained low-lying areas the capillary flow transports high amounts of
water soluble salts from the shallow, „stagnant” groundwater with high salt
concentration and unfavourable sodium-carbonate(bicarbonate) type ion
composition to the overlying soil horizons. Due to the strongly alkaline soil
solution, the Ca and Mg salts (mostly carbonates and bicarbonates) are not
soluble and Na
became absolutely predominant in the migrating soil
solution which leads to high ESP even at relatively low salt concentration.
saturation of heavy-textured soils with high amount of
expanding clay minerals results in unfavourable physical-hydrophysical
extreme moisture regime
of these soils, which are their
main ecological constrains and the limiting factors of their fertility,
productivity and agricultural utility. The simultaneous hazard of waterlogging
or overmoistening, and drought sensitivity in extensive lowland areas,
sometimes in the same places within a short period, necessitates a precise,
“double function” soil moisture control against their harmful
ecological/economical/social consequences. Most of the environmental constrains
(including salinity/alkalinity/sodicity) can be efficiently controlled:
prevented, eliminated, or - at least - moderated. But this needs permanent care
and proper actions: adequate soil and water conservation practices based on a
comprehensive soil/land degradation assessment. It includes continuous
registration of facts and changes (monitoring); exact and quantitative knowledge
on the existing soil processes, their influencing factors and mechanisms.