著者

Md. Fuad Mondal Md. Asaduzzaman Makoto Ueno Mikiko Kawaguchi Shozo Yano Takuya Ban Hideyuki Tanaka Toshiki Asao

出版者

一般社団法人 園芸学会

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.MI-113, (Released:2016-04-23)

被引用文献数

19

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The consumption of vegetables and fruits rich in potassium (K), such as melons and strawberries, is restricted in chronic kidney disease (CKD) patients. Therefore, we attempted to produce low-K strawberry fruits through management of a KNO3 fertilizer in nutrient solution from anthesis to the harvest period. A general trend of decreasing K content in fruit was observed with the decrease of KNO3 concentration in the nutrient solution. Among four strawberry cultivars, the fruit of the ‘Toyonoka’ exhibited a K reduction of about 64% when plants were grown in nutrient solution with KNO3 at 1/16 of the normal level. Citric acid and ascorbic acid contents of ‘Toyonoka’ fruit were reduced with decreasing KNO3 concentrations in the nutrient solution. Although the reduced NO3− of the nutrient solution was adjusted by using Ca(NO3)2 to obtain low-K strawberries, growth, yield and quality did not vary with this adjustment. Compared with the typical level of K in strawberry fruit of 170 mg/100 g FW (Standard Tables of Food Composition in Japan, 2011), a 23.5% decrease (130 mg/100 g FW) in K was found in 1/32 level of KNO3. The K contents of plant parts suggested that the low KNO3 level was responsible for the low K absorption, which may have affected the translocation and accumulation of K into fruit. Therefore, 1/32 level of KNO3 in nutrient solution lowers the fruit K content considerably.

著者

Md Asaduzzaman Toshiki Asao

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-R009, (Released:2020-03-11)

被引用文献数

11

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Strawberry plants are grown in hydroponics for higher quality and yield, as this system excludes soil-borne disease issues. Recycled hydroponics is practiced to make cultivation cost-effective, sustainable, and environmentally friendly. However, due to recycling of hydroponic nutrient solution, plant root exudates accumulate, leading to autotoxicity, a form of allelopathy that inhibits growth and development. In recent decades, commercial cultivation of strawberry under greenhouse and plant factory conditions following recycled hydroponics has been widely adopted globally. Subsequently, yield decline has also been reported due to development of autotoxicity from the accumulated root exudates. In recycled hydroponic systems, strawberry plant growth is inhibited by root exudates that contain mainly phenolic acids in the culture solution. In this regard, elimination of these accumulated root exudates or allelochemicals from the culture solution would restore inhibited plant growth and yield. A number of research studies have been conducted on autotoxicity in strawberry and possible mitigation methods. These studies suggested that addition of activated charcoal in the nutrient solution, supplementation of auxin on leaves, electro-degradation of root exudates in nutrient solution, and supplementation of amino acids and/or LEDs can effectively remove/degrade/mitigate autotoxicity in strawberry grown under recycling hydroponics. This review mainly discusses the autotoxicity phenomenon in strawberry under recycled hydroponics, the responsible allelochemicals and their mechanism of action, mitigation methods and future research endeavors in this field.