great grandparent

Effect of Selection Method for Succession of Great Grandparent Silkworm on Maintenance of Characteristics

家蚕母种继代蛾区选择方法对种性维持的影响

For maintenance of the good traits of practical varieties, five different methods for succession of great grandparent silkworm were applied and compared.

为了有效保持生产实用家蚕品种的优良性状，在家蚕母种继代繁育中采用5种选择方法选择继代蛾区，探讨种性维持效果。

"My adopt-a-grandparent friends are very nice, have great stories and are very wise" , she says.

“我收养一个祖父母朋友都很漂亮，而且非常英明伟大的故事”，她说。

Over much of the globe, the living standard of, say, a farmer in 1750 would not differ greatly from that of his great-grandparent.

例如，在全世界大多数地区，一个农民在1750年的生活水平和他的曾祖辈没有太大区别。