Abstract

Soil salinity is one of the major abiotic stresses restricting the use of land for agriculture because it limits the growth and development of most crop plants. Improving productivity under these physiologically stressful conditions is a major scientific challenge because salinity has different effects at different developmental stages in different crops. When supplied exogenously, proline has improved salt stress tolerance in various plant species. Under high-salt conditions, proline application enhances plant growth with increases in seed germination, biomass, photosynthesis, gas exchange, and grain yield. These positive effects are mainly driven by better nutrient acquisition, water uptake, and biological nitrogen fixation. Exogenous proline also alleviates salt stress by improving antioxidant activities and reducing Na+ and Cl− uptake and translocation while enhancing K+ assimilation by plants. However, which of these mechanisms operate at any one time varies according to the proline concentration, how it is applied, the plant species, and the specific stress conditions as well as the developmental stage. To position salt stress tolerance studies in the context of a crop plant growing in the field, here we discuss the beneficial effects of exogenous proline on plants exposed to salt stress through well-known and more recently described examples in more than twenty crop species in order to appreciate both the diversity and commonality of the responses. Proposed mechanisms by which exogenous proline mitigates the detrimental effects of salt stress during crop plant growth are thus highlighted and critically assessed.

Highlights

  • Salinity is a major abiotic stress that severely affects crop plant growth and development from seed germination to harvest

  • It is estimated that more than 7% of total land and almost 20% of arable land are affected by salinity with affected areas increasing at an annual rate of Proline and Salt Stress Tolerance

  • This trend coincides with the increasing challenge of ensuring global food security, so it is even more urgent to be able to exploit more arable land and increase crop productivity even in infertile soil by developing efficient and tolerant crops able to grow in salty conditions (Rengasamy, 2006; Safdar et al, 2019)

Read more

Summary

Introduction

Salinity is a major abiotic stress that severely affects crop plant growth and development from seed germination to harvest. Exogenous application of proline can effectively improve tolerance of plants to salt stress through the regulation of endogenous proline metabolism, partly achieved through differential expression of specific proline-related genes.

Results
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call