Plant breeding collects, induces and rearranges genetic diversity followed by selection. Breeding may contribute to diversity in farmers’ fields or significantly reduce it. History has numerous examples of both. The diversity of many crops have gone through domestication, dispersal and modernization bottlenecks. Between these major decreasing processes, diversity has picked up through different evolutionary processes, and plant breeding affected by policies. Major negative effects of plant breeding on diversity have been recorded following the modernization bottleneck, but alternative breeding strategies have come up as well, both in the formal system and in the interphase between formal and farmers’ seed systems. Multiline breeding and participatory plant breeding are introduced as examples to also analyse effects of current developments in technology and policy. This paper intends to shed some light on the questions: how will current developments in technology and policy affect crop genetic diversity? Are we heading for a new bottleneck—either a molecular or a policy bottleneck, or a combination of both? Or could the future become more diverse? We look at the relationship between breeding, policies, and crop genetic diversity in farming systems with a birds-eye view. Notably because of current policy trends we warn for a new diversity bottleneck.

中文翻译：

---

植物育种和多样性：一个麻烦的关系？

植物育种收集、诱导和重新排列遗传多样性，然后进行选择。育种可能有助于农民田地的多样性或显着减少多样性。历史上有很多这样的例子。许多作物的多样性经历了驯化、传播和现代化的瓶颈。在这些主要下降过程中，多样性通过不同的进化过程和受政策影响的植物育种得到了提升。在现代化瓶颈之后，植物育种对多样性的主要负面影响已经被记录下来，但替代育种策略也出现了，无论是在正式系统中还是在正式和农民种子系统之间的中间阶段。介绍了多系育种和参与式植物育种作为示例，以分析当前技术和政策发展的影响。本文旨在阐明以下问题：当前的技术和政策发展将如何影响作物遗传多样性？我们是否正在走向新的瓶颈——分子瓶颈或政策瓶颈，或两者兼而有之？或者未来会变得更加多样化？我们以鸟瞰的眼光审视农业系统中育种、政策和作物遗传多样性之间的关系。值得注意的是，由于当前的政策趋势，我们警告了新的多样性瓶颈。当前技术和政策的发展将如何影响作物遗传多样性？我们是否正在走向新的瓶颈——分子瓶颈或政策瓶颈，或两者兼而有之？或者未来会变得更加多样化？我们以鸟瞰的眼光审视农业系统中育种、政策和作物遗传多样性之间的关系。值得注意的是，由于当前的政策趋势，我们警告了新的多样性瓶颈。当前技术和政策的发展将如何影响作物遗传多样性？我们是否正在走向新的瓶颈——分子瓶颈或政策瓶颈，或两者兼而有之？或者未来会变得更加多样化？我们以鸟瞰的眼光审视农业系统中育种、政策和作物遗传多样性之间的关系。值得注意的是，由于当前的政策趋势，我们警告了新的多样性瓶颈。