连作年限对红壤旱地芝麻产量和主要病害的影响

为了探讨连作年限对红壤旱地芝麻产量和主要病害的发生规律的影响,采用定位试验,研究了正茬、连作1 a、2 a、3 a对芝麻相关性状的影响。结果表明,连作1 a、2 a、3 a与正茬比较芝麻产量分别降低14.0%、45.6%、64.4%,单株蒴果数分别减少25.4%、17.5%、55.9%,千粒重分别减少20.5%、8.5%、22.2%。连作1 a与连作3 a的每蒴粒数较正茬分别减少2.0%和14.5%。红壤旱地上芝麻连作会使茎点枯病和青枯病的病情指数呈现上升趋势,其中茎点枯病从正茬的6.80%增加到连作3 a的51.63%,而青枯病从正茬的2.54%增加到连作3 a的44.75%。这说明芝麻连作对产量、产量构成因素、主要病害病情指数的影响大,为了提高芝麻产量应实行轮作换茬。

Effects of Continuous Cropping Years on Sesame Seed Yield and Disease Index of Red Soil Upland

In order to study the effective of continuous cropping years on sesame yield and the occurrence rules of disease index in red soil upland, fixed experiments on the effect of the first-planting, continuous cropping 1 year, 2 years, 3 years on sesame related traits in four years were conducted. The results showed that the yield of continuous cropping 1 year, 2 years and 3 years was reduced by 14.0%, 45.6% and64.4%, respectively, compared with the first-planting. The capsule number of per plant decreased by 25.4%, 17.5% and 55.9%, respectively;and 1000-grain weight decreased by 20.5%, 8.5% and 22.2%, respectively; grain number per pod of 1 year and 3 years of continuous cropping decreased by 2.0% and 14.5%, respectively. Disease index of sesame stem blight and bacterial wilt in red soil upland showed a rise trend, stem blight first-planting increased from 6.80% to 51.63% of the 3 years of continuous cropping, and bacterial wilt increased from 2.54% to 44.75%after three years. As a result, there was a negative influence on yield, yield components and disease index of sesame continuous cropping, and it should advocate the rotation to increase sesame yield.