Tanjuro Goto

Multiple loss-of-function putative aminotransferase alleles contribute to low pungency and capsinoid biosynthesis in Capsicum chinense

Capsicum chinense is a domesticated hot pepper species in the Capsicum genus that originated in the Amazon and is consumed in USA, the Caribbean and South America. Although a characteristic of this species is high pungency, some non-pungent or low-pungent strains, called “Aji Dulce” (sweet pepper in Spanish), exist in the Caribbean region. In the present study, low-pungent C. chinense accessions were analyzed in order to elucidate the genetic mechanisms responsible for low pungency. All low-pungent C. chinense accessions in this study carried non-functional alleles of putative aminotransferase (pAMT), which catalyzes the formation of vanillylamine from vanillin in the capsaicinoid biosynthetic pathway. These low-pungent accessions produced capsinoids, low-pungent capsaicinoid analogs. The pamt mutation in each strain was characterized using allele-specific markers, and one novel pamt allele (pamt7) was identified. The pamt7 had a new hAT family transposon insertion in the second exon region, which caused the loss of pAMT expression. pamt7 is apparently an ancestral allele for pamt6 because the 7-bp insertion in pamt6 can be regarded as a footprint of the transposon. A phylogenetic analysis of pamt alleles was performed to examine their relationships. Combined with previously reported pamt alleles, the Tcc family transposon insertion and its excision were involved in the generation of various pamt alleles in C. chinense. A phylogenetic analysis of pamt alleles showed that at least five occurred within C. chinense after speciation of the Capsicum genus. In conclusion, the results of the present study identified pamt as the main and most frequent gene controlling low pungency in C. chinense. Allelic variations in loss-of function pamt and their wide distribution demonstrated the potential of C. chinense bioresources for genetic improvements to pungency and metabolic profiles in hot pepper breeding programs.

Influence of Environmental Conditions on the Chrysanthemum Leaf Yellow Spot - Measurement of the Leaf Yellow Spot at Early Stage -

Abstract In recent years, yellow spots appear on the leaf of chrysanthemums in many species, which brought commercial problems. The purpose of this study is to examine the measurement of the spot in order to make the influence of environmental conditions clear. Image instrumentation with transmitted light made possible to measure the spot at early stage, which was difficult for reflected light. The method is used the gap of the light quantity between the spot and others. It is involved in chlorophylls and the use of the suitable light color make measuring easy. The portable device using this method was produced experimentally and leaf yellow spot was measured with this device, which brought the basic data, the state get worse with time and the relationship between the spot and environmental conditions.

Transplant Production on Stock with Automatically Subirrigated Cell Flat. (Part 2). Growth and Productivity of Transplants as Affected by Fertigation Frequency Controlled in Response to Solar Radiation or Scheduled in Time Course.

We demonstrated the practical utility of solar radiation mediated fertigation control for transplant production in a cell flat with an automatic ebb-and-flow fertigation system. Furthermore, we investigated seasonal changes in growth and productivity of stock (Matthiola incana R. Br.) cv. White Dorse as affected by fertigation frequency controlled in response to solar radiation (5 or 10 MJ · m-2) and scheduled time course (once or twice per day).The shoot dry weight of transplants and fresh weight of cut flowers were higher in plants fertigated with every 5 MJ · m-2 of solar radiation, sown between late April and late July. In plants sown during other periods, there was no significant difference in growtn and productivity among plants fertigated differently. When the plants sown in June were fertigated twice per day, the exposure was 5 MJ · m-2 in average of cumulatlve solar radiation from fertigation to subseauent fertigation. However, the maximum cumulative value exceeded 8 MJ · m-2. Water stress caused by the high solar radiation accompanied by high temperature and large saturation deficit may have resulted in reduced growth of the transplants and decreased quality of the cut flowers.When the stock transplants were grown in a cell flat (220 cells of 12ml cell volume), suffcient but not excess fertigation could be obtained by supplying nutrient solution every 5 MJ · m-2 of solar radiation with an automatic ebb-and-flow fertigation system.

Studies on Quality Evaluation of Chrysanthemum Cut Flower(Part 1)Relation between Experts'' Evaluation and Morphological Characteristics of Cut Flower

あいまいな基準で行われている輪ギクの切り花の評価を定量的に表現するため, 3層構造を有するニューロモデルを用いた評価を行った.その結果, 以下のことが明らかとなった.1) 入力パラメータとして, 切り花全長, 主茎径, 葉面積, 花首長を用いたニューロモデル, さらに第1葉全長または主茎の曲がりを加えたニューロモデルは評価者の評価を良く再現できた.2) ニューロモデルを用いたシステムにより, 従来評価者のあいまいで不確実な評価でなく, 定量的な評価の可能性が示唆された.3) 本評価システムを自動化するに当たっては, 画像から抽出容易な特徴量を選択し, 適当な数の入力パラメータを構成するための評価指標を作成する必要があると考えられた.

Machine vision based quality evaluation of chrysanthemum cut flower

Abstract Cut flower evaluation has been usually conducted by human sense and its criteria are uncertain and subjective. In this paper, machine vision based quality evaluation was done using neural networks to quantify the ambiguous criteria. As input parameters of neural networks, cut flower length, stem diameter, leaf area, and etc. were selected, while human evaluation score was used for an output parameter. The neural networks were trained by KNT method. From the results, it was observed that output value satisfactorily agreed the human evaluation score. The error was less than the human error resulted from the human double check procedure.