**6. Conclusions and Challenges Ahead**

Climate change, water scarcity and human activities are increasing soil salinity and depleting arable land. High salinity in soil or water is a serious threat to plant growth and prevents plants from reaching their genetic potential, which reduces yields and threatens food security. Grafting can reduce the negative effects of salinity on tomato scions and thus provides an alternative way to enhance salt tolerance and maintain fruit yield and quality under salt stress. The selection of salt-tolerant rootstocks is an important strategy for enhancing salt tolerance. Testing and screening of available commercial cultivars, landraces and wild relatives, and inbred lines or hybrids involving a resistant parent under salt stress conditions is a prerequisite for successful grafting. This technique can cause both positive and negative effects on yield and fruit characteristics when tomatoes are grown under saline conditions. Weather, salinity level, soil type, cultural practices and consumer preferences also vary in different locations or countries, so the combination of scion and rootstock should be selected carefully at plants morphometric, physio-biochemical and molecular planes to get the maximum benefit from grafting.

**Author Contributions:** H.S. Wrote the initial draft of the review including yield and quality of grafted tomatoes under salinity; A.K. First draft of physio-biochemical and molecular aspects. P.K. Improved the first draft, contributed to the morphological, physio-biochemical mechanism, and prepared the graph. M.C.K., G.C. and Y.R. critically revised and improved the review paper. All authors have read and agreed to the published version of the manuscript.

**Acknowledgments:** The authors acknowledge Punjab Agricultural University, Ludhiana and ICAR-Central Arid Zone Research Institute, Jodhpur, India for providing supports.

**Conflicts of Interest:** The authors declare no conflict of interest.

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