Method for producing germinated plant seeds, a method for producing germination induction raw material seeds, extract composition of germination processing plant seeds, and screening method

A screening method for a plant seed candidate for use in producing a target substance, comprising:

• a pre-treatment step of maintaining test plant seeds under atmosphere conditions of a carbon dioxide concentration of 2000 ppm to 50,000 ppm and an oxygen concentration of 7 vol % to 19 vol % continuously for 5 hours or more, followed by watering, a germination induction step of inoculating the test plant seeds with a microbial pathogen after the pre-treatment step, and placing the test plant seeds under an environment in which germination is inducible and the pathogen is viable,
• a step of detecting the target substance in the test plant seeds after the germination induction step, and
• a step of selecting the plant seed candidate for use in producing the target substance based on the detection results.