福寿螺危害早稻秧苗的水体环境影响因素初步研究

Study on the Environmental Factors Affecting the Early Rice Seedlings Harmed by the Pomacea canaliculata

福寿螺是一种对湖南水稻生产区造成严重危害的外来入侵生物,而目前尚缺乏绿色高效的防控手段。本文以福寿螺幼螺(壳高5~15 mm)和成螺(壳高>25 mm)为研究对象,探究温度(10~40℃)、pH值(4~10)、水位(0~10 cm)3种水体环境因素对福寿螺早稻秧苗平均最大摄食率的影响。结果表明,福寿螺幼螺在30℃时的秧苗平均最大摄食率最高,达51.8%;成螺则在35℃时最高,为11.3%;在10℃左右的水体环境中,幼螺和成螺均活动缓慢,几乎不主动取食秧苗。在不同pH范围内,成螺与幼螺摄食率的变化相似,均为pH值为6.5~8.5时摄食率较大,平均最大摄食率为8.2%~9.4%;pH值为4左右时摄食率最低,其中幼螺为1.4%,成螺仅0.4%。不同水位处理条件下,幼螺与成螺的表现也一致,均为无水条件下的平均最大摄食率最低,其中幼螺为9.9%,成螺仅2.8%;水位为6 cm时,幼螺和成螺的平均最大摄食率均最高,分别为45.0%和9.2%。结果表明,福寿螺具备较强的抗不利水体环境因素的能力,但低温、过酸、无水条件均会严重抑制福寿螺的取食,从而间接地影响其活动、存活、生长发育和繁殖。该结果可为合理调节水稻田水深和采取耕作管理措施降低福寿螺的危害提供理论依据。

Pomacea canaliculata is a kind of alien invasive organism which causes serious harm to Hunan rice production area,but there is still a lack of green and efficient means of prevention and control at present.In this paper,the young snail(shell height 5~15 mm)and adult snail(shell height>25 mm)were taken as the research objects to explore the effects of temperature(10-40℃),pH value(4-10)and water level(0-10 cm)on the average maximum feeding rate of early rice seedlings.The results showed that the average maximum feeding rate of young snails was the highest(51.8%)at 30℃,while that of adult snails was the highest(11.3%)at 35℃.In the water environment of about 10℃,both young snails and adult snails move slowly and hardly take the initiative to feed on seedlings.In different pH ranges,the changes of feeding rates of adult snails and young snails were similar:the feeding rate was higher when the pH value was 6.5 to 8.5,and the average maximum feeding rate was 8.2%to 9.4%.When the pH value was about 4,the feeding rate was the lowest,1.4%for young snails and 0.4%for adult snails.Under different water level treatment conditions,the performance of young snails and adult snails were also the same,and the average maximum feeding rates of young snails and adult snails were the lowest under anhydrous conditions,of which the average maximum feeding rates of young snails and adult snails were 9.9%and 2.8%,respectively.When the water depth was 6 cm,the average maximum feeding rates of young snails and adult snails were the highest,45.0%and 9.2%,respectively.The results showed that Pomacea canaliculata has a strong ability to resist adverse water environmental factors,but low temperature,over-acid and anhydrous conditions will seriously inhibit the feeding of Pomacea canaliculata,thus indirectly affecting its activity,survival,growth and reproduction.The results can provide a theoretical basis for reasonably adjusting the water depth of rice field and adopting tillage management measures to reduce the harm of Pomacea canaliculata.