Well before the green revolution in the 1960s, hybrid maize technology that had originally been developed in the USA spread across the world, starting before the Second World War. This article uses a framework that analyses the type of transfer (materials, knowledge, or capacity), the roles of diverse actors, and farmer demand and its market context, to trace the diffusion of hybrid technology to Latin America, Asia, Europe, and Africa up to 1970. The article also highlights the importance of access to diverse germplasm from the Americas provided by indigenous farmers. A handful of US public institutions promoted the spread of hybrid technology, with US private seed companies sometimes playing a secondary role. However, most cases of successful transfer were led by national scientists embedded in local institutions, who were able to link to local seed systems and farmers. By the mid 1970s, the aggregate impacts of these efforts were of the same magnitude as for the well-known and much publicized green revolution wheat varieties. Nonetheless, adoption of hybrid maize across and within countries was very patchy, relating to differences in scientific capacity, type of farmer, agro-ecology, and complementary investments in seed systems and extension. Consequently, impacts were often highly inequitable.

中文翻译：

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杂交玉米的全球化，1921-70

早在 1960 年代绿色革命之前，最初在美国开发的杂交玉米技术在第二次世界大战之前就开始传播到世界各地。本文使用一个分析转移类型（材料、知识或能力）、不同参与者的作用、农民需求及其市场背景的框架，来追踪混合技术在拉丁美洲、亚洲、欧洲和直到 1970 年的非洲。文章还强调了获取美洲土著农民提供的各种种质资源的重要性。少数美国公共机构推动了混合技术的传播，美国私营种子公司有时扮演次要角色。然而，大多数成功转移的案例都是由嵌入当地机构的国家科学家领导的，他们能够与当地的种子系统和农民建立联系。到 1970 年代中期，这些努力的总体影响与众所周知且广为宣传的绿色革命小麦品种的影响相同。尽管如此，由于科学能力、农民类型、农业生态以及对种子系统和推广的补充投资等方面的差异，在国家间和国家内采用杂交玉米的情况非常不完整。因此，影响往往是高度不公平的。以及对种子系统和推广的补充投资。因此，影响往往是高度不公平的。以及对种子系统和推广的补充投资。因此，影响往往是高度不公平的。