Introduction

Tomato plants are vulnerable to several viruses that can result in significant economic losses to farmers. The effective control of these viruses heavily relies on the identification and understanding of the genetic factors that control plant-virus interactions. Genes on specific chromosomes can have a considerable impact on virus resistance in tomatoes. This article aims to explore what chromosome controls virus infection in tomato plants.

Background

Tomato yellow leaf curl virus (TYLCV) and tomato mosaic virus (ToMV) are two of the most common viruses affecting tomato plants. Studies have shown that resistance to these viruses is governed by different gene clusters on chromosomes 4 and 6. These genes have been identified through a process of genome-wide association studies, which have led to the identification of several loci associated with resistance to these viruses.

Chromosome 4

Studies have shown that chromosome 4 harbors several quantitative trait loci (QTLs) that play a role in controlling the susceptibility of tomato plants to TYLCV. Among these QTLs is the Ty-3 gene, which is known to provide resistance to all known strains of TYLCV. The Ty-3 gene is also linked to other genes that have been associated with resistance to other tomato viruses. Other genes located on chromosome 4, including Tsw and Sw-5, have also been shown to provide resistance to TYLCV.

Chromosome 6

Chromosome 6 contains several QTLs that contribute to tomato resistance against ToMV. A study conducted by Yoshioka et al. (2012) identified a quantitative trait locus on chromosome 6 that was linked to resistance to ToMV. This QTL was located close to the location of the Tm-2^2 gene, which is known to provide resistance to tomato mosaic virus. Other genes located on chromosome 6, including Tm-2^a and Tm-2^b, have also been shown to provide resistance to ToMV.

Conclusion

In conclusion, resistance to TYLCV and ToMV in tomato plants is determined by complex interactions between viral and plant genes. However, genes on specific chromosomes have been identified as playing a critical role in controlling the susceptibility of tomato plants to these viruses. Chromosome 4 and chromosome 6 have both been shown to contain several QTLs associated with virus resistance. The identification of these genetic factors provides a valuable foundation for the development of new tomato varieties with enhanced resistance to these viruses, which could help reduce the economic losses incurred by farmers.