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遗传侵蚀,始于19世纪中叶欧洲微粒子病的泛滥,使欧洲蚕业几致绝灭。例如1853年法国产茧量为2.5万吨,但受微粒子病的侵袭,1865年法国产茧只有0.5万吨;意大利蚕业受到同样危机,欧洲蚕种断绝,纷纷到中国和日本购买蚕种维持蚕业,苟延残喘。为何欧洲蚕种抵抗不住微粒子病,而中国蚕种则有史以来从未受到这种病害的威胁呢?对此在农业植物方面,有详尽的论著。 苏联学者瓦维洛夫毕生研究,发现作物起源中心,常在热带、亚热带山区,咫尺之外,土壤即有差异,这种差异导致植物差异。人类文化中心,也常常位于这些作物起源中心或其附近,人们从这些多种多样的植物中选择适合于食用者进行栽培,就兴起以种
Genetic erosion, beginning in the mid-19th century, the spread of European particle disease, sericulture extinction in Europe. For example, in 1853, the amount of cocoon produced in France was 25,000 tons. However, due to the attack of microparticle disease, only 18,000 tons of cocoon were produced in France in 1865; the same crisis in Italy and the elimination of European silkworm eggs all came to China and Japan to purchase silkworm eggs Sericulture, linger. Why is Europe’s silkworm eggs resistant to particulate diseases, while Chinese silkworm eggs have never been threatened by this disease ever since? There have been elaborate treatises on agricultural plants. The Soviet scholar Vavilov life study, found that the center of crop origin, often in the tropical, subtropical mountains, close to the soil that is different, this difference leads to plant differences. Human cultural centers are also often located at or near the center of these crop origins, where people choose from among a wide variety of plants suitable for edible cultivation,