also: せいようだね
noun
Western cultivar; Western variety; Western breed
Refers to plant cultivars, animal breeds, or varieties originating from Western countries. Used in agricultural, horticultural, or biological contexts.
この西洋種のトマトは甘みが強い。
This Western variety of tomato is very sweet.
西洋種の犬は日本でも人気がある。
Western breeds of dogs are popular in Japan as well.
在来種 refers to native or traditional varieties, while 西洋種 specifically denotes those introduced from the West.
Compound of 西洋 (せいよう, 'Western') and 種 (しゅ/だね, 'seed, breed, variety'). The reading せいようしゅ is the standard Sino-Japanese compound reading.