Analysis of free-living nematodes in Chinese yam farm with the soil improvement material.
2020 年 7 巻 1 号 p. 07001-1-07001-6
詳細
2020 年 7 巻 1 号 p. 07001-1-07001-6
A soil improvement material including Bacillus subtilis (1 ´ 107/g dry weight) and free-living nematodes (1 ´ 104/10 g wet weight) was developed using biomass resources such as cedar bark, dried sludge, and dehydrated soil. The improvement material (3 kg/m2) was introduced into a test field of Chinese yam, while the soil samples were then collected once a week from the predetermined areas of the farm. In this study, the genetic variations of the free-living nematodes associated with the soil improvement material were investigated. The nucleic acid sequences of the ITS1 and ITS2 regions were compared, resulting in the identification of the nematodes species Cephalobidae sp., mycophagous nematode and Phelenchoides sp. Furthermore, predatory nematodes, Paractinolaimus sp. and Rhyssocolpus, which have been proven to be effective in the control of continuous crop disorders, were observed. The yield of the Chinese yam was evaluated, and it was revealed that it remained the same as when chemical pesticides were used, suggesting that the soil amendment material can inhibit the crop damage similarly to chemical pesticides.
