三裂叶豚草雄花序分化的气候效应分析

Analysis of climatic effects in male inflorescence differentiation of Ambrosia trifida

【背景】三裂叶豚草是一种外来恶性杂草,它的入侵不仅影响当地的生物多样性和生态系统,而且给农牧业造成巨大的经济损失。此外,其花粉量大,是引起人体一系列过敏反应的致敏源。【方法】通过对2008～2010年三裂叶豚草分化时期和气象因素进行调查,以当年分化开始前一个月至分化结束的日最高气温、日最低气温、日平均气温、相对湿度、日照时间等数据,分析影响三裂叶豚草雄花序分化的气象因子。【结果】雄花序从未分化期至成熟期平均需26d。三裂叶豚草营养生长后期,较短的日照时间和日平均气温、较高的相对湿度和较大的温差等环境条件有利于三裂叶豚草雄花序较早地开始分化。而在分化早期,长时间较高的相对湿度不利于雄花序的分化。【结论与意义】外界环境的变化能够影响三裂叶豚草雄花序的分化,对其分化开始时间起决定性作用。本研究为制定合理的三裂叶豚草防治措施提供了理论依据,同时为进一步研究其生物安全性提供了参考。

[Background]The giant ragweed（Ambrosia trifida L.） is an invasive alien weed,not only threatening native biodiversity and ecosystems but also cause a series of allergic reactions in humans.Understanding the factors influencing pollen production would open possibilties to better manage this invasive plant and reduce pollen production.[Method]The effects of climatic factors on the male inflorescence differentiation of the giant ragweed were analyzed based on the meteorological data from 2008～2010.Five climatic factors,including daily maximum ground temperature,daily minimum ground temperature,daily mean temperature,relative humidity,duration of sunshine were statistically analyzed.[Result]Male inflorescence completes the whole development in 26 days.During the last period of vegetative growth,lower sunshine and daily mean temperature,higher relative humidity（RH）,comparatively large difference in temperature could speed up the differentiation time of the male inflorescence.During early differentiation stage,higher RH is beneficial,although a long time with higher relative humidity is not beneficial.[Conclusion and significance]Environmental change plays a decisive role in male inflorescence differentiating of giant ragweeds.It will offer reference for determining control time and measures of giant ragweeds.