Saengcheonggukjang, known as Natto in Japan, is a soybean fermented food which is made from steamed soybean, Bacillus and water. Demand of Saengcheonggukjang has increased because it does not have much smell compared to Cheonggukjang. Seven varieties of Saengcheonggukjang were investigated and compared in terms of 100 seed weight, quality characteristics, hard seed rate, and water absorption rate in order to determine the suitability of Korean soybeans. In addition, each characteristic of Saengcheonggukjang was compared. ‘Hoseo’ and ‘Haewon’ showed low 100 seed weight with 8.41 g and 8.11 g, respectively. The water absorption rate was higher in ‘Hoseo’ and ‘Pungwon’ than in Japan varieties. The yield of Saengcheonggukjang was significantly different for each variety. No differences were observed in yield and hardness of Saengcheonggukjang with respect to the varieties and sowing date. ‘Haewon’ showed the highest amino nitrogen content with 575.0 mg%. Viscous material content did not appear to differ between varieties. These results suggested that ‘Hoseo’ and ‘Haewon’ can be considered as suitable candidates for yield and quality of Saengcheonggukjang compared to Japan varieties.

Organ size control is a fundamental developmental processes for higher plants as well as a promising target trait for molecular breeding in crop plants. Genetic mechanisms how plant organs grow to a certain size remains still unclear. Here we present the identification and characterization of a genetic mutant, big flower1-1 (bif1-1) in Arabidopsis that exhibits bigger organ size primarily due to increased cell size. Genetic analysis indicated that it is a single, semi-dominant mutation. Phenotypic analysis showed that bif1-1 exerts pleiotropic effects: it caused bigger seed size, bigger seedling, bigger leaf, thicker stem, increased trichome branching, smaller fruit, and bigger pollen. Microscopic analysis suggested that the bigger organ size in bif1-1 mutant is primarily attributed to increased cell size. Gene expression analysis indicated that most of growth-control genes tested were not altered in bif1-1 mutant. Instead, expression of ARGOS and auxin-inducibility of ANT were reduced in bif1-1 mutant. Our ongoing positional on the corresponding gene would not only shed light on the molecular mechanisms how plants adopt final organ size but also provide a promising genetic resource for genetic engineering of flower- and seed-size in crop plants.

Toward molecular understanding of flower senescence/abscission, we have identified a mutant, designated as dea1-1D (dealyed abscission1-1D), with delayed flower senescence/abscission syndrome from activation-tagged pools. Phenotypic analysis revealed pleiotropic effects of dea1-1D mutation including delayed flowering as well as smaller serrated leaves. Genetic analysis showed that it is a dominant mutation. Molecular analysis on the flower senescence syndrome indicated that dea1-1D might define novel regulatory branch of flower abscission, controlling expression of ethylene-responsive AP2 transcription factor. On the contrary, triple responses was not affected by dea1-1D mutant. Though the penetrance was not complete, the mutant phenoytpes was shown to be tightly linked with the T-DNA selection marker, BASTA-resistance. We identified the T-DNA insertion site through molecular cloning of the T-DNA flanking genomic DNA and found that a neighboring gene was overexpressed in the dea1-1D mutant. Together with gene expression analysis, we will discuss possible function of DEA1 during flower senescence and abscission.