品种混合种植条件下小麦条锈病的空间分布

本研究把抗病品种冀麦２４与感病品种津丰１号按５种不同比例进行混合种植，在这种情况下，调查并分析了小麦条锈病在田间传播梯度的变化。结果表明，感病品种津丰１号纯合种植时，随着病害的发展病害传播梯度发生了由大到小的显著变化，而在感病与抗病品种混合种植条件下，尤其是在两者比例为１∶１和１∶３时，这种梯度变化不明显，并始终保持在一个中间水平。由此可见，品种混合种植时，其中的抗病品种对病原菌的传播起到了有效的阻挡作用，这也是为什么品种混合种植能起到抗病增产作用的机制之一。

Spacial Distribution of Stripe Rust Under the Sowing of Wheat Variety Mixtures

The mixtures of Jinfeng 1 and Jimal 24,Which have different resistance to Puccinia striiformis. were sowed at five different ratios. In spring,disease gradients of striperust were investigated and analysed. Results showed that disease gradients from the beginning to the end of epidemic changed signiticantiy when the susceptible cultivar Jinfeng 1was sowed purely or the change remained stable when Jinfeng 1 mixed with the resistantcultivar jimal 24,especially at the ratios of 1∶1 and 1∶3. Accordingly,the barrier effect ofresistnat cultivar in mixtures plays an important role in preventing the spread of disease.That is why variety mixture has its advan. tage of reducing disease seriousness and increasing yeild of crop