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The changing climate is intensifying salt stress globally. Salt stress is a menace to cotton crop quality and yield. The seedling, germination, and emergence phases are more prone to the effects of salt stress than other stages. Higher levels of salt can lead to delayed flowering, a reduced number of fruiting positions, shedding of fruits, decreased boll weight, and yellowing of fiber, all of which have an adverse effect on the yield and quality of the seed cotton. However, sensitivity toward salt stress is dependent on the salt type, cotton growth phase, and genotype. As the threat of salt stress continues to grow, it is crucial to gain a comprehensive understanding of the mechanisms underlying salt tolerance in plants and to identify potential avenues for enhancing the salt tolerance of cotton. The emergence of marker-assisted selection, in conjunction with next-generation sequencing technologies, has streamlined cotton breeding efforts. This review begins by providing an overview of the causes of salt stress in cotton, as well as the underlying theory of salt tolerance. Subsequently, it summarizes the breeding methods that utilize marker-assisted selection, genomic selection, and techniques for identifying elite salt-tolerant markers in wild species or mutated materials. Finally, novel cotton breeding possibilities based on the approaches stated above are presented and debated.

Upland cotton is one of the main cultivated species of cotton, and salt stress is an important factor in its growth and development. Wall-associated receptor kinase galacturonan binding (GUB_WAK_bind) is an extracellular domain of wall-associated kinase (WAK), which can sense the environment and play a role in the response to plant stress.In this study, the GUB_WAK_bind gene in Gossypium hirsutum was identified and analyzed by bioinformatics at the whole genome level, including its physicochemical properties, evolutionary development, gene structure, chromosome positioning, cis-acting elements in the promoter, etc., and the expression of the GUB_WAK_bind genes under salt stress were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). A total of 22 GUB_WAK_bind gene members were identified in Gossypium hirsutum and divided into three subgroups by evolutionary development and motif analysis, most of which contained motif 5, which is similar to the motif pattern of subgroup members. The number of exons in this gene family is between 1 and 4, the number of introns is between 0 and 3, and 22 gene members are distributed on 14 chromosomes of Gossypium hirsutum. Almost all gene members have adverse stress response elements in their promoter region. The expression analysis in response to salt stress showed that the selected six genes were induced by NaCl stress with significant expression differences (P 0.05).The results of this study have a certain reference value for understanding the evolution and function of GUB_WAK_bind genes and studying the salt tolerance genes of Gossypium hirsutum.