Genes for Yield Stability in Tomatoes

Area of Science:

• Plant genetics
• Crop breeding
• Agricultural science

Background:

• Adapting crops to unstable environments necessitates understanding the genetic basis of yield stability.
• Identifying quantitative trait loci (QTL) and specific genes is crucial for improving crop resilience.

Purpose of the Study:

• To map QTL associated with yield stability in *Solanum pennellii* introgression lines (ILs).
• To identify genes that, when perturbed, affect yield stability.
• To explore the potential of wild relatives for enhancing tomato yield stability.

Main Methods:

• Conducted a meta-analysis of 12 years of field harvest data from 76 *Solanum pennellii* ILs.
• Mapped five QTL affecting yield stability, with IL10-2-2 showing significant improvement.
• Field-tested 48 morphological mutants, identifying a 'canalization' mutant (*canal-1*) affecting trait stability.

Main Results:

• IL10-2-2 improved yield stability without impacting mean yield, validated over four years.
• *canal-1* mutant, mapped to a DNAJ chaperone gene (Solyc01g108200), reduced stability across multiple traits.
• CRISPR/CAS9 generated alleles of *canal-1* indicated specific genetic changes lead to instability.

Conclusions:

• Historical phenotypic data is valuable for discovering genes controlling plant stability.
• The wild species *Solanum pennellii* is a promising source of QTL for improving tomato yield stability.
• DNAJ chaperone genes play a role in phenotypic canalization and yield stability.