Plant breeding 植物育种

Chick-please

A neglected crop is about to get a high-tech makeover

第一段：

Pliny the elder, a Roman administrator with a sideline in philosophy, appreciated the complexities of the chickpea. In his master work, “Naturalis Historia”, he wrote of it: “This plant presents considerable differences in reference to size, colour, form and taste.” One type, he reported, came in the shape of a ram’s head. Another, the Venus pea, was white, round and smooth. A third had small, angular seeds.

老普林尼是一位罗马行政官员，副业研究哲学，他喜欢研究鹰嘴豆的复杂性。在他的杰出作品《博物学历史》中，他写道：“这种植物在大小、颜色、形状和味道方面存在着相当大的差异。”他记录称，有一种是公羊头的形状。另一种是维纳斯豌豆，白色，圆滑。第三种的种子很小，有棱角。

第二段：

These days, chickpeas are still as varied, though the main types now recognised are the large, light-coloured Kabuli and the smaller, darker Desi. They are grown in more than 50 countries, particularly in Asia and Africa, and contribute 11.5m tonnes of protein-rich pulses to the world’s food supply, making them the third most productive leguminous food crop, after beans and peas. But their variety is under-exploited, and much of it is found in poorly studied “landraces”—local varieties that have some genetic coherence but are not as selectively bred as modern cultivars.

如今，鹰嘴豆仍然是多种多样的，尽管现在公认的主要类型是大的、浅色的卡布利和小的、深色的德西。它们生长在50多个国家（在亚洲和非洲特别多），为世界粮食供应贡献了1150万吨富含蛋白质的豆类，使其成为仅次于黄豆和豌豆的第三大豆科粮食作物。但它们的品种还没有得到充分的开发，其中很多是在研究不足的“地方品种”中被发现的，这些地方品种具有一定的遗传一致性，但不像现代品种那样有选择性地培育。

第三段：

Recognising this, a group of researchers from the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) and 40 other organisations, led by Rajeev Varshney of Murdoch University, in Australia, have produced a comprehensive “pan-genome” derived from the cultivated plant, Cicer arietinum, and seven of its wild relatives, which they have now published in Nature. One of their purposes was to identify blocks of genes, called haplotypes, that encode particular, desirable properties, and which could be bolted together in various combinations to yield both better chickpeas overall, and chickpeas better suited to particular sets of circumstances. In a world where circumstances are changing rapidly, that matters. A study published in 2016, for example, estimated that shifts in temperature and rainfall patterns could, by 2069, decrease chickpea yield in parts of the world by almost 20%.

有人意识到这一点。一组研究人员（来自国际半干旱热带作物研究所和其他40个组织，由澳大利亚默多克大学的拉杰夫·瓦尔什尼领导），他们已经从栽培植物鹰嘴豆及其7个野生近缘植物中制备出了一个全面的“泛基因组”，他们现在已经在《自然》杂志上发表了这篇文章。他们的目的之一是鉴定称为单倍型的基因块，这些基因块编码特定的、理想的特性，并且可以以各种组合的方式栓接在一起，从而产生整体上更好的鹰嘴豆和更适合特定环境的鹰嘴豆。在一个环境瞬息万变的世界里，这么做很重要。例如，2016年发表的一项研究估计，到2069年，气温和降雨模式的变化可能使世界部分地区鹰嘴豆产量下降近20%。

第四段：

Building on an initial map of more than 28,000 chickpea genes, published by ICRISAT in 2013, Dr Varshney’s team sequenced 3,171 cultivated chickpeas and 195 wild examples taken from collections around the world. That added 1,582 previously unknown genes to the list, including ones that encode responses to environmental factors such as cold, acidity and oxidative stress. The result is the most comprehensive genetic map of any vegetable species.

在ICRISAT2013年发布的2.8万多个鹰嘴豆基因的初始图谱基础上，瓦尔什尼博士的团队对3171个栽培鹰嘴豆和195个来自世界各地的野生样本进行了测序。这就增加了1582个以前未知的基因，包括编码对寒冷、酸度和氧化应激等环境因素反应的基因。结果是所有蔬菜物种中最全面的遗传图谱。

第五段：
Crucially, the samples came with useful data about the characteristics of the plants they were taken from, known in the argot as their phenotype. That allowed the team to cross-correlate between genotype and phenotype, identifying which bits of the former appeared responsible for what parts of the latter. As a consequence, they think they have identified 24 haplotypes that do useful things like increasing seed weight, improving yield per plant and reducing the time it takes for a plant to become mature enough to flower.

至关重要的是，这些样本提供了有用的数据，这些数据是关于它们所采集的植物的特征，在行业术语中被称为它们的表现型（显型）。这使得研究小组能够在基因型和表现型之间进行交叉关联，确定前者的哪些部分与后者的哪些部分有关。因此，他们认为他们已经确定了24种单倍型，作用大，如可以增加种子重量、提高单株产量和缩短植物成熟开花所需的时间。

第六段：

Looking back at the original collections, they found around 80% of cultivars lacked these beneficial blocks of genes, suggesting there was considerable room for improvement. Knowing exactly which genes are involved means the process of breeding in those improvements can be done quickly. Instead of waiting for a plant to grow and mature, you can check its genes shortly after it has germinated, and throw it away if you do not want it.

回顾最初的收集，他们发现大约80%的品种缺少这些有益的基因块，这表明有很大的改进空间。确切地知道哪些基因参与其中意味着可以很快完成这些改进的育种过程。不用等植物生长和成熟，你可以在植物发芽后不久检查它的基因，如果你不想要的话，就把它扔掉。

第七段：

Upgrades suitably developed, the question will be how to get them into the wider world. Dr Varshney says that big agricultural and seed companies tend to have limited interest in chickpeas.That means more reliance on smaller firms and co-operatives for distribution. If this can be done, though, the humble chickpea will join the big boys like rice and soyabeans as crops whose genes have been analysed for the betterment of human nutrition.

如果育种过程完成升级，那么问题将是--如何让它们进入更广阔的世界。瓦尔什尼博士说，大型农业和种子公司对鹰嘴豆的兴趣往往有限。这意味着更多地依靠小公司和合作社进行分销。不过，如果能做到这一点，级别低下的鹰嘴豆将加入大米和大豆等大的农作物行列。这些经过基因分析的农作物，可以改善人类营养。