小麦黑穗病的防治

小麦黑穗病都是以种子带菌传播为主的病害,因此,进行种子消毒处理,基本上可以达到预防的目的。其主治方法如下:1)建立无病种子田。2)抽穗前后在田间拔除穗,带出田外烧毁,减少病菌传播。3)小麦黑穗病,除种子带菌外,还有土壤和粪肥带菌。一般可用50%多菌灵可湿性粉剂,或立克锈按种子重量的0.2~0.3%拌种。4)浸种:每50kg麦种用20%多菌灵0.5kg,先用水稀释,药液以浸种子为宜,在20~30℃温度下浸了3~4h即可。

Forecasting freight volume based on wavelet denoising and FG-Markov

To eliminate the grey bias and improve ant-jamming performance of the standard grey-Markov forecasting model,a forecasting model based on wavelet packet decomposition and fuzzy grey Markov(FG-Markov)is proposed considering the characteristics of randomness and nonlinearility of freight volume forecasting.Firstly,based on the data analysis ability of wavelet packet to non-stationary random signal,wavelet packet decomposition is used to improve the analysis ability of data signal by decomposing historical freight volume data into wavelet packet component.On this basis,FG-Markov chain is proposed to obtain the transfer probability matrix of wavelet packet coefficients by introducing fuzzy grey variables,and forecast the freight volume by reconstructing wavelet packet coefficients.Finally,an example of Lanzhou railroad hub is carried out in order to testify the validity and applicability of this forecasting model.Compared with neural network model and other forecasting models,the proposed forecasting model can improve the forecasting accuracy under the same conditions.The forecasting accuracy of wavelet packet decomposition and FG-Markov is not only greater than that of any other single forecasting models,but also superior to that of other traditional combinational forecasting models,which can meet the actual requirements of freight volume forecasting.