Effects of salt stress on eco-physiological characteristics in Robinia pseudoacacia based on salt-soil rhizosphere

Abstract

Robinia pseudoacacia is the main arbor species in the coastal saline-alkali area of the Yellow River Delta. Because most studies focus on the aboveground parts, detailed information regarding root functioning under salinity is scare. Root traits of seedlings of R. pseudoacacia including morphological, physiological and growth properties under four salinity levels (CK, 1‰, 3‰ and 5‰ NaCl) were studied by the pot experiments to better understand their functions and relationships with the shoots. The results showed that seedling biomass decreased by the reduction of root, stem and leaf biomass with the increase of salinity levels. With increasing salinity levels, total root length (TRL) and total root surface area (TRSA) decreased, whereas specific root length (SRL) and specific root area (SRA) increased. Salt stress decreased root activity (RA) and the maximum net photosynthetic rate (Amax) and increased the water saturation deficit (WSD) significantly in the body. Correlation analyses showed significantly correlations between root morphological and physiological parameters and seedling biomass and shoot physiological indexes. R. pseudoacacia seedlings could adapt to 1‰ salinity by regulating the root morphology and physiology, but failed in 5‰ salinity. How to adjust the water status in the body with decreasing water uptake by roots was an important way for R. pseudoacacia seedlings to adapt to the salt stress.

The Positive Effect of Different 24-epiBL Pretreatments on Salinity Tolerance in Robinia pseudoacacia L. Seedlings

“…Salt stress always results in water deficit, ion toxicities and imbalances, and oxidative stress, damaging plant cells and organs, limiting plant growth, and even causing death. For example, 85.73 mM NaCl increased the water saturation deficit in weak roots and limited the biomass accumulation of individual R. pseudoacacia [11]. The growth of the medicinal plant, L. japonica, was reduced by 200 mM NaCl because of negative effects on the ionic uptake and their distribution to plant organs [12].…”

Towards sustainable agriculture for the salt‐affected soil

“…Additionally, the salt‐affected area is increasing at a rate of 10% yearly because of high evaporation, low rainfall, inadequate irrigation, and other irrational anthropogenic activity (Himabindu et al, ; Liu et al, ; Mose et al, ). By 2050, the salinized area will exceed 50% of global arable land (Liu et al, ; Mao, Kang, et al, ; Mao, Zhang, et al, ; Sun et al, ). So breeding salt‐tolerant crops is vital to feed the increasing population (Yamaguchi & Blumwald, ).…”

“…By 2050, the salinized area will exceed 50% of global arable land (Liu et al, 2017;Mao, Kang, et al, 2016;Mao, Zhang, et al, 2016;Sun et al, 2018). So breeding salt-tolerant crops is vital to feed the increasing population (Yamaguchi & Blumwald, 2005).…”

Integration into plant biology and soil science has provided insights into the total environment

“…Bai et al (2016)reported the latest result by using sewage sludge as an initial fertility driver for rapid improvement of mudflat salt-soil, starting a new way for raising salt-soil fertility on large-scale with low cost. Mao et al (2016) and He et al (2016)studied eco-physiological characteristics of adaptable forest in the Yellow River Delta, China, further pointing out the significance for constructing stable vegetation in the region. Chenchouni (2016)established the gradient linkage between edaphic factors and inland halophytes, providing important examples for elucidating pant-soil interacting system.…”

“…Plant biology is extremely interdisciplinary, reaching from agricultural science to paleobotany to soil science and molecular physiology to ecology. It uses the latest developments in computer science, optics, molecular biology, and genomics to address challenges in model systems, agricultural crops, and ecosystems; and explores the form, function, development, diversity, reproduction, evolution, and uses of both higher and lower plants, as well as their interactions with other organisms throughout the biosphere Sytar et al, 2016;Mao et al, 2016;Li et al, 2016aLi et al, , 2016bXu et al, 2016aXu et al, , 2016bXu et al, , 2016cZhang et al, 2016) (Fig. 1).…”