2017托福考试阅读真题全面解析及答案（5）

　　常青藤小编为大家带来2017托福考试阅读真题全面解析及答案(5)，欢迎大家参考!更多相关内容请关注本站!

　　2017托福考试阅读真题全面解析及答案(5)

　　学科分类：农业类

　　题目：The Green Revolution

　　内容回忆：

　　第1段: The green revolution can date as far back to 1930s. 农业科学家做实验以manipulate the seed of crops to improve productivity. 随后指出科学家把中国大米和印度大米作为 parents研究出IR8,优点是 bigger head of grain and stronger stem。虽然IR8提高了产量，但是科学家仍然不满足，于是研究出了IR36,优点是：来自13个parents(母本)，可以抵抗15种pests，110 days of growing period and three crops each year。

　　第2段：global hunger makes the green revolution extraordinary。India can be self-sufficient in crop production and Asia increases the crop production.

　　第3段：非洲的地理环境使得其受益较小，故科学家研发出新的super rice，which can be transplanted that depended on seeding directly instead of seedling。

　　第4段：指出the green revolution 有很多detractors，比如 chemical fertilizers and pesticides can reduce the organic matter in the soil, and many small-scale farmers lack of financial resource to purchase genetical enhanced seeds.