Technology development to regulate the growth of vegetables and flowers, and study on floral traits.

Study on the growth control technique of vegetable and ornamental crop by “Light”

Plants utilize the light not only as the primary energy source, but as a signal for their morphogenesis. Growth and morphogenesis of plants are strongly affected by various light conditions, the intensity, photoperiod and quality. In particular, the light quality is the most focused factor in plant growth. The artificial light sources have been “evolved” to achieve a long life, enough energy efficient and higher irradiation power, such as the light emitting diodes (LED). LED can irradiate narrow spectrums, so those specific lights could control a specific plant growth response, plant shape, flowering timing and so on, without any chemical plant growth regulators. Those light control technologies have a great possibility for smart and cool crop production system. In our laboratory, we study to develop the control system of vegetable and ornamental crops by using the signal and energy irradiated by artificial lighting.

>Overnight supplemental lighting by LED

>Morphogenesis control by light quality and analysis on that mechanism and quality control with artificial lighting

>Control of poly-phenol and ascorbic acid contents by light condition

Development of tomato plant canopy monitoring system by Micro-sensors

Growth condition is the most important factor to increase the crop production and quality. However, it could be difficult to get useful information on the environmental condition inside crop canopy, and apply those data and information to practical agricultural production in the field. If it could be possible to let growers to know those micro climate information, inside the plant canopy, they could achieve a very high productivity and quality on their products. In recent years, micro sensing technology has been developed, and big data analysis method has been also promoted according to the ITC development. Now a day, open-data is used to reinforce the social securities and increase our QOL. In the agricultural production area, we have also tried to apply those data analysis method to the adequate field management. Here, we have tried to analyze the plant canopy inside environmental information by using micro sensors and camera, and develop a new crop production management system.

>Tomato plants canopy analysis by micro-light sensors

>Analysis of photosynthate movement under various environmental condition.

>LED supplemental lighting system to increase the tomato yield with high density planting

Search for genes that determine color, organ and shape of the flower

 In Japan, many horticultural cultivars, which have been selected from wild plants, have been produced through crossbreeding since Edo era (1603-1867). Our research group is interested in the traditional azalea and primrose cultivars which have various kinds of floral traits related to flower color and structure (Fig 1). As an example, azalea, a traditional Japanese flower, has several flower colors ranging from red, purple, to white. It also has flower color sports and different flower color patterns such as striped, flecked, speckled and white margined. These flowers contain pigments called anthocyanin, which is synthesized by enzymes that are encoded by structural genes involved in the anthocyanin biosynthetic pathway (Fig. 2). In line with this, our research focuses in determining the relationship between flower color, major pigment constitution and gene expression to the synthesis of anthocyanin. Traditional Japanese flowers, azalea and primrose, are used in the investigation.

 On the other hand, petal shape and floral organ constitution of primrose are also manifold. Furthermore, it is reported that floral organs are expressed in accordance to the ABC model (Fig. 3). Thus, we are investigating the mechanism of floral organ and shape development in primrose using double flowers and mutants.

In the near future, we aim to identify the origin of each azalea and primrose cultivar, and develop new cultivars using molecular information and data obtained from present researches.