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32.One such novel idea is that of inserting into the chromosomesof plants discrete genes that are not a part of the plants naturalconstitution：specifically，the idea of inserting into nonleguminousplants the genes，if they can be identified and isolated，that fit theleguminous plants to be hosts for nitrogen-fixing bacteria. Hence，theintensified research on legumes. 这其中的一个新颖思想就是，在植物的染色体内注入并非是该植物自然构造一个部分的那些不相关联的因基：具体而言，这一思想是，在非豆科植物内注入这样一些基因，倘若这些基因可被辨识出来并被分离开来，而这些基因业已使豆科植物宜于充当那些具备固氮作用的细菌的寄主。由此，对豆科植物的研究日趋深入。 33.It is one of natures great ironies that the availability ofnitrogen in the soil frequently sets an upper limit on plant growtheven though the plants leaves are bathed in a sea of nitrogengas.下述情形真可谓是自然界的一个莫大讽刺：土壤中所能获得的氮肥量往往对植物的生长构成了一个上限，虽然植物的叶子被沐浴在一片氮气的海洋中。 34.Unless they succeed，the yield gains of the Green Revolutionwill be largely lost even if the genes in legumes that equip thoseplants to enter into a symbiosis with nitrogen fixers are identifiedand isolated，and even if the transfer of those gene complexes，once theyare found，becomes possible. | 
