Beneficial Microbes and Molecules for Mitigation of Soil Salinity in Brassica Species: A Review

Abstract

Salt stress results from excessive salt accumulation in the soil can lead to a reduction in plant growth and yield. Due to climate change, in the future climatic pressures, changed precipitation cycles and increased temperature will increase the pressures on agriculture, including increasing severity of salt stress. Brassica species contains oilseed and vegetable crops with great economic importance. Advances in understanding the mechanisms of salt stress in Brassica plants have enabled the development of approaches to better induce plant defense mechanisms at the time of their occurrence through the use of beneficial microorganisms or molecules. Both endophytic and rhizospheric microbes contribute to the mitigation of abiotic stresses in Brassica plants by promoting the growth of their host under stress conditions. In this review we summarized so far reported microorganisms with beneficial effects on Brassica plants and their mode of action. Another approach in mitigating the harmful effect of soil salinity may involve the application of different molecules that are involved in the stress response of Brassica plants. We reviewed and summarized their potential mode of action, methods of application and pointed out further research directions.

Mechanisms of Kale (Brassica oleracea var. acephala) Tolerance to Individual and Combined Stresses of Drought and Elevated Temperature

“…It was particularly observable in 404 and 411 accessions that were selected as tolerant ones for further examination of tolerance mechanisms. The correlation between proline accumulation and stress tolerance is controversial [ 23 ]. Comparative studies between Brassica species/varieties under drought and salt stress indicate that a higher increase in proline content is associated with more sensitive species/varieties [ 11 , 13 ], which is in agreement with the results obtained here, while a positive correlation between proline accumulation and stress tolerance was found in a comparative study of different Brassica juncea cultivars [ 24 ] and in rapeseed ( B. napus ) [ 25 ] subjected to abiotic stress.…”

The Effect of Hydro-Priming and Proline Priming of Lettuce (Lactuca sativa L.) Seeds on Germination, Photosynthetic Pigments and Metal Metabolism under Cadmium Stress

“…In recent years, the application of different molecules at the seed level, known as seed priming, has been investigated as a method to improve stress tolerance in plants [14]. Seed priming is based on controlled seed hydration, which places seeds in a "primed state" that stores this brief pulse and provides for more robust and resilient plants [15].…”

“…Seed priming is based on controlled seed hydration, which places seeds in a "primed state" that stores this brief pulse and provides for more robust and resilient plants [15]. This process triggers metabolism prior to germination, without the formation of radicles, and involves the activation of enzymes, the buildup of metabolites, and other processes that help shorten the lag time during germination and have other positive effects on seed performance [14]. Priming seeds with silicone [16,17] and salicylic acid [18] has already shown promise as a priming agent for reducing Cd toxicity in lettuce.…”