Research Area: Horticultural Science 
Research Specialization: Protected Horticultural Science 
Name: TOMIYOSHI, Keita

Keywords:protected horticulture, Nelumbo nucifera,

        control of growth environment, sustainable cultivation technology

Recent Research

1. Ecological characteristics of edible lotus.  

Elongation and enlargement of rhizome in edible lotus are controlled by photoperiod, that is to say, rhizome elongates and enlarges under long and short days, respectively. However, early maturing cultivars grown in plastic tunnels and greenhouses exhibit rhizome enlargement even in long-day conditions. This suggests the presence of other factors controlling rhizome elongation/enlargement in edible lotus. We study the effects of various growth environments on the elongation and enlargement of edible lotus rhizomes and clarify the ecological characteristics of edible lotus.

2. Establishment of the edible lotus protected cultivation system.

In general, cultivation of edible lotus requires a large growth area, which makes difficult to control the growth environment. If it becomes possible to cultivate edible lotus in a small container, productivity can be expected to increase by controlling of growth environment in greenhouses. Therefore, we aim to explore and breed cultivars that are suitable for cultivation in a small growth area and establish stable production techniques by controlling of growth environment.

3. Exploration and breeding of vegetable cultivars and development of stable

       production techniques for the global warming.

 In recent years, increased temperatures caused by global warming have adversely affected the quality and yield of leafy and fruit vegetables. To solve these issues, we study to explore and breed cultivars that can be grown under high temperature conditions and develop stable production techniques by controlling of growth environment.


Tomiyoshi, K. et al. (2017) The photoperiodic response of lotus rhizome morphogenesis is determined quantitatively. Acta Horticulture. 1171: 83-88.

Tomiyoshi, K. et al. (2022) Characteristics and genetic control of rhizome coloration in red rhizome lotus. Hort. J. 91: 366-374.

Ozaki et al. (2023) Hasunokenkyushokai 4-Konkeinohidaiseigyotochakushoku. Seibutsu no Kagaku Iden (In Japanese). 222-227. NTS, Tokyo.

© 2023 Faculty of Agriculture, Kagawa University. All rights reserved.