Quantitative evaluation for the accuracy of spawning event detection of marine fishes by multiple environmental DNA indicator

多重环境DNA指标定量评价海洋鱼类产卵事件检测准确性

• 批准号: 22K14938
• 负责人: 河合 賢太郎
• 金额: $ 2.91万
• 依托单位: Hiroshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Early-Career Scientists
• 财政年份: 2022
• 资助国家: 日本
• 起止时间: 2022-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-22K14938/
• 关键词: 環境DNA; 魚卵; クロダイ; 産卵生態

環境DNA調査手法は水を汲むだけと手軽で自然破壊のリスクが少ないため、多方面で生物調査ツールとしての活用が期待されている。本研究の目的は、海産魚類の産卵研究において環境DNAの時空間的な濃度分布情報が産卵イベントの探知に利用できるか定量的に評価することである。初年度はまず、種苗生産用の飼育クロダイから得られる受精卵の採卵量と水槽内に放出される環境mtDNA濃度との間に相関がみられるかを検証した。クロダイ親魚の飼育水槽水を5月から7月にかけて10日に1回採水し、同時に採卵量を記録した。その結果、クロダイ受精卵の採卵量と環境DNA濃度との間には正の相関がみられた。フィールド調査では、広島湾におけるクロダイの産卵期に環境mtDNA濃度が増加するか、増加した場合、卵密度と環境mtDNA濃度との間に正の相関がみられるかを確認した。広島湾において、クロダイの産卵期とその前後を含む4月から7月にかけては10日に1回、8月から3月にかけては月に1回の頻度で採水調査を実施した。産卵期には同時に浮性卵を採集し、クロダイ卵の密度を算出した。その結果、産卵期にはクロダイの環境mtDNA濃度が上昇し、クロダイ卵密度と環境mtDNA濃度との間に正の相関がみられた。海産魚類の産卵期を推定するうえで、環境mtDNA濃度の季節変化は有効な情報として利用できる可能性がある。今後は産卵期だけでなく産卵場でも環境mtDNA濃度が上昇するか調べ、環境mtDNAの時空間的濃度分布が産卵場の特定に有効か評価する。また、魚類の産卵期において環境DNAの由来物質となりうる精液、受精卵、体表粘液、鱗、排泄物について単位量あたりの環境DNA放出量を調べ、精液や受精卵といった産卵由来の物質が放出する環境DNAに特異的な指標を探索する。さらに、その指標が広島湾のクロダイの産卵期や産卵場で上昇するか確認する。

Environmental DNA treatment techniques, water supplies, water supplies, handsets, natural breakdowns, small amounts of food, and many aspects of biological equipment are widely used and are expected to be used actively. The purpose of this study is to study the degree distribution of environmental DNA time and space in order to find out how to make use of the quantitative analysis of environmental temperature. At the beginning of the year, the fertilised eggs were successfully released from the water tank in the first year, and the mtDNA of the environment was released from the water tank. Please make sure that the water in the aqueduct is closed in May and July, and the water is returned on the 10th. At the same time, the egg count is recorded. The results showed that the egg number of fertilized eggs was significantly higher than that of the fertilized eggs in the DNA environment. The mtDNA of the environment during the egg period and the density of eggs, and the density of eggs. The period before and after the egg period includes April, July, October, August, March, March, month, month and month. The density of floating eggs and the density of eggs were calculated at the same time during the egg period. The results showed that during the egg period, the mtDNA of the environment was higher than that of the environment, and the egg density of the environment was significantly higher than that of the environment. The mtDNA of the environment was significantly higher than that of the control. During the egg period, it is presumed that there is a significant impact on the mtDNA of the environment, and the possibility of taking advantage of the climate is very important. In the future, during the egg period, there will be environmental mtDNA temperatures and the distribution of environmental mtDNA temperatures in time and space. there will be environmental pollution in specific egg farms. The source of DNA in the environment of oviduct and ovum, the amount of semen, fertilized egg, body surface mucus, oocyte and excreta, the amount of DNA released from the environment, the amount of semen released from fertilized eggs, the origin of fertilized eggs and the origin of fertilized eggs was released into the environmental DNA test. This means that the eggs are confirmed in the egg field during the egg period.