杂交

• Producing hybrid corn is a lengthy process which must be done by hand .
  生产杂交玉米是一个漫长的过程，要靠手工劳作。
• The total variation range in seed weight for all crosses was 16. 7 mg .
  所有杂交在种子重量上的总变异范围为167毫克。
• The chinese yellow breed is perhaps one of the earliest products of this cross .
  中国黄牛可能是最早的这种杂交后代之一。
• Host resistance and fungal virulence parallel each other in the cross .
  寄生的抗病性的病原菌的毒力在杂交中是势均力敌的。
• Moffet found chlorosis in the progeny of the crosses between two kinds of trees.
  Moffet在两种树杂交产生的后代中发现了萎黄病。
• The possibility of making distinct races by crossing has been greatly exaggerated .
  对于杂交可能产生特殊品种一说，实在夸张过甚。
• Scientists have bred new hybrid plants and animals which yield more food .
  科学家培育的许多新的杂交植物和动物，提供了更多的食物。
• To map 100 mutants by this method would necessitate nearly 5, 000 crosses .
  用这种方法来绘制100个突变型的遗传图就要做5000个杂交。
• Species occupying the same ecological niches in the same areas usually do not cross .
  在同一地区占有同样生态生境的两个种通常不杂交。
• In truly doubtful cases, only test crosses will reveal the actual genotype .
  在确实可疑的情况下，只有通过杂交试验才能揭示出真正的基因型。