The flowering gene SINGLE FLOWER TRUSS drives heterosis for yield in tomato

Intercrossing different varieties of plants frequently produces hybrid offspring with superior vigor and increased yields, in a poorly understood phenomenon known as heterosis. One classical unproven model for heterosis is overdominance, which posits in its simplest form that improved vigor can result from a single heterozygous gene. Here we report that heterozygosity for tomato loss-of-function alleles of SINGLE FLOWER TRUSS (SFT), which is the genetic originator of the flowering hormone florigen, increases yield by up to 60%. Yield overdominance from SFT heterozygosity is robust, occurring in distinct genetic backgrounds and environments. We show that several traits integrate pleiotropically to drive heterosis in a multiplicative manner, and these effects derive from a suppression of growth termination mediated by SELF PRUNING (SP), an antagonist of SFT. Our findings provide the first example of a single overdominant gene for yield and suggest that single heterozygous mutations may improve productivity in other agricultural organisms

Transcriptomic effects of Aspergillus alliaceus on Orobanche during its pathogenesis

The aim of this study was to investigate the pathogenicity of Aspergillus alliaceus (Aa), a fungal bio-control agent, on Orobanche by transcriptomic tests. For this reason, the expression of several genes was analysed comparatively in the experimental (fungi applied) and control (fungi-free) groups. After fungal infection, the expression of antioxidant enzyme genes SOD (Mn-super-oxide dismutase), CAT (catalase), and SOD2 (Zn-super-oxide dismutase) and the genes GS (Glutamine synthetase), HSP70 (heat-shock protein), and apoptosis [BCL2, BAX, caspase3 (CASP3)], which are related to protein metabolism, were investigated in the both groups. In gene expression studies, gene expression of SOD was almost 2.5 times higher in the experimental group than in the control group (fungus-free, intact), while the expression levels of other antioxidant genes (CAT and SOD2) were significantly reduced. While GS, which is the N and protein metabolism balancer, was found to be relatively low as compared to the control group, however, the level of HSP70 (protein folding, chaperoning) was quite higher than the control. Gene expressions of all apoptotic genes, BAX (=apoptosis suppressive gene), CASP3 and BCL (=apoptosis inducer genes), were significantly lower than control group. All the results found for the control group were determined to be statistically significant. It was concluded that during Aa pathogenesis, (1) the increased SOD value was associated with ROS (reactive oxygen species) threats, (2) the fungi disturbed protein synthesis metabolism, and finally, (3) the inhibited antioxidant and apoptosis-based pathways compared to the control group. These conclusions were discussed in the light of slow but constantly lethal effects of Aa comparatively to other pathogenic fungus, Fusarium.TUBAP (Trakya University, Scientific Researches Foundations) [TUBAP 2014-82]I thank Prof. Dr. Oguzhan DOGANLAR for his valuable comments and TUBAP (Trakya University, Scientific Researches Foundations) with the Project Number TUBAP 2014-82