小麦条锈病药剂防治试验

1962年和1963年,分别在信阳和郑州进行三次田间药剂防治小麦条銹病試驗結果表明:在叶面防治效果方面,超过0.5％对氨基苯磺酸10％以上的有0.5％与0.3％“閩农五号”、氟化鈉600倍、1000倍、氟矽酸鈉600倍、1％氨基苯磺酸鈉、1％氨基苯磺酸鋅、1％氨基苯磺酸鎳、0.1％与0.2％氮化鎳、0.2％氟化鎳及0.2％醋酸鎳等12种;超过1—10％或基本上相等的有1％常州氟鋇、1％氨基苯磺酸铁、0.1％与0.2％硫酸鎳四种;其中药效較好而又无药害、比对照增产10—35％的有1％氨基苯磺酸鈉、0.5—1％常州氟鋇、0.3—0.5％“閩农五号”、0.5％氨基苯磺酸铁及0.5％对氨基苯磺酸等;药效尚好而药害輕微、比对照增产10—20％的有1％氨基苯磺酸铁盐、0.5％鋅盐、0.5％鎳盐、0.1％醋酸鎳及氟矽酸鈉600倍等。田間药剂防治的适当时期和次数,根据病情动态和噴药效果分析,在河南省中南部地区建議以小麦的孕穗初、孕穗末或抽穗初、揚花期三次噴药为最好,灌浆以后噴药一般不起作用,如早春气温较高,病情上升迅速,則可在拔节期加噴一次。

ON THE CHEMICAL CONTROL OF STRIPE RUST OF WHEAT

During the last two years (1962 & 1963), 16 chemicals including 28 concentrations have been tested for the control effect of stripe rust (Puccinia glumarum Erik. & Henn.) of winter wheat. Results of these experiments showed that in comparing with 0.5% sulfanilic acid spray which was previously demonstrated to be an effective chemotherapeutant against stripe rust, the following sprays namely 0.3 & 0.5% Min-Nung No. 5, 1:600 & 1:1000 dilutions of sodium fluoride, 1:600 dilution of sodium fluoro-silicate, 0.5% sodium sulfanilate, 1% zinc sulfanilate, 1% nickel sulfanilate, 0.1 & 0.2% nickel chloride, 0.2% nickel fluoride and 0.2% nickel acetate all decreased the severity of stripe rust by more than 10%; While 1% fluoro-barium, 1% ferric sulfanilate, 0.1 & 0.2% nickel sulfate, 0.1% nickel acetate and 0.5% ferric sulfanilate surpassed 0.5% sulfanilic acid by 1-10% in effectness. Other applications appeared less effective or even ineffective. Greater efficacy of rust control on leaves always correlated with the increase of the weight per 1000 kernels by 5-20%. There was no evidence for the correlation between rust control and the number of grains per 100 spikes. Increases of 10-30% in yield were obtained in following applications:1.0% sodium sulfanilate, 0.5% formulae of fluorobarium, 0.3 & 0.5% Min-Nung No. 5, 0.5% ferric sulfanilate and 0.5% sulfanilic acid. 0.1% ferric sulfanilate, 0.5% zinc sulfanilate, 0.5% nickel sulfanilate, 0.1% nickel acetate and 1:1000 dilution of sodium fluoro-silicate increased the yield by 10-20%. In other applications owing to the plant injury caused by the spray, no increasing or even decreasing in yield were observed. The plant injury produced by some applications such as fluorine compounds and others has caused the shrinkage of grains and therefore decreasing chiefly the weight of grains and also reducing eventually the grains per spike. In the case of heavy injury the germination rate of these shrinking seeds was also affected. It was shown that the sodium fluoride caused more injury than the sodium fiuoro-silicate. Applying the 1:600 dilution of the later with 2 or 3 successive sprays before the blooming period cauld have been more advantageous and of practical value. According to the analysis of the annual occurence of stripe rust in the districts of the middle-south part of Honan province it is suggested that the time suitable for 3 successive applications of chemical spray should be at the beginning of booting, beginning of heading and blooming period of wheat. After the development of kernels, the chemical application appeared ineffective for stripe rust control. When the air temperature during early spring is relatively high and thus the stripe rust pustules increase rapidly, it is necessary to add a supplimentary spray at the jointing stage of wheat for satisfactory control.