Selection for inflorescence architecture with improved flower production and yield is common to many domesticated crops. However, tomato inflorescences resemble wild ancestors, and breeders avoided excessive branching because of low fertility. We found branched variants carry mutations in two related transcription factors that were selected independently. One founder mutation enlarged the leaf-like organs on fruits and was selected as fruit size increased during domestication. The other mutation eliminated the flower abscission zone, providing “jointless” fruit stems that reduced fruit dropping and facilitated mechanical harvesting. Stacking both beneficial traits caused undesirable branching and sterility due to epistasis, which breeders overcame with suppressors. However, this suppression restricted the opportunity for productivity gains from weak branching. Exploiting natural and engineered alleles for multiple family members, we achieved a continuum of inflorescence complexity that allowed breeding of higher-yielding hybrids. Characterizing and neutralizing similar cases of negative epistasis could improve productivity in many agricultural organisms.

中文翻译：

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绕过归化基因对番茄产量的负上位效应

对于许多驯化作物来说，选择具有提高的花产量和产量的花序结构是常见的。但是，番茄的花序类似于野生祖先，并且育种者由于低生育力而避免了过多的分枝。我们发现分支变体携带两个独立选择的相关转录因子中的突变。一种创始人突变扩大了果实上的叶状器官，并被选择为驯化过程中果实大小的增加。另一个突变消除了花的脱落区，提供了“无节节”的果梗，从而减少了落果并促进了机械收获。由于上位性，将这两个有利性状堆叠在一起会导致不良的分支和不育，育种者克服了抑制子。然而，这种压制限制了弱分支带来的生产率提高的机会。利用多个家庭成员的天然和工程等位基因，我们获得了连续的花序复杂性，从而可以育成高产杂种。鉴定和中和相似的阴性上皮病例可以提高许多农业生物的生产力。