美国农业部用一株吉野樱和另外一个品种培植出一棵杂交樱花树，其抗病虫害的能力更强。

这棵新培植的杂交樱花树的渊源可一直追溯至1912年日本赠与美国的3,000棵樱花树。它是在美国农业部（U.S. Department of Agriculture ）设在首都华盛顿的国家植物园（National Arboretum）中由一株吉野樱（Yoshino）和另外一个品种杂交培植的。这株吉野樱是由原始樱花树复制而成的一棵“克隆”树。

为什么要培植杂交樱花树呢？因为樱花树的遗传基础狭窄，可能更易于遭受虫害和病害的侵扰。将它们与美国不太常见的品种杂交，能培育出生命力更强、更能抗病虫害的品种。

原始树种的基因谱系也正在得到保护。已由原始的樱桃树中存活下来的树繁育出400棵新树。去年，这些新树中有120棵被送往日本。

这棵新培植的樱花树以威廉·塔夫脱（William Taft）总统的夫人海伦·塔夫脱（Helen Taft）的名字命名。1912年3月27日，她同当时美国驻日本大使的夫人珍田女士（Viscountess Iwa Chinda）一起在朝汐湖（ Tidal Basin）种下了最早的两棵樱花树。

The U.S. Department of Agriculture creates a new variety of cherry tree by crossing a Yoshino cherry — a clone of one of the original 3,000 trees Japan gave to the United States in 1912 — with another variety. The new hybrid may be more resistant to insects and disease.

A new flowering cherry tree hybrid traces its lineage back to the 3,000 trees Japan gave to the United States in 1912. It was created at the National Arboretum, a U.S. Department of Agriculture facility in Washington, by crossing a Yoshino with another variety. The Yoshino is a clone of one of the original trees.

Why create hybrids? Because cherry trees have a narrow genetic base, they may be more vulnerable to attack by insects or disease. Crossing them with species not often grown in America can create stronger, more resistant trees.

The genetic lineage of the original trees is also being protected. About 400 new trees have been propagated from the survivors of the original cherry trees. Last year, 120 of these propagates were sent to Japan.

The new cherry tree is named the “Helen Taft” after the wife of President William Taft. She and Viscountess Iwa Chinda, wife of the Japanese ambassador to the United States at the time, planted the first two cherry trees at the Tidal Basin on March 27, 1912.

See U.S. Marks 100th Anniversary of Japan's Gift of Cherry Trees.