A STUDY OF CHEMICAL CONTROL TECHNIQUE TO FUSARIUM HEAD BLIGHT IN WHEAT
Shang Hongsheng Wang Shuquan Jing Jinxue(Department o/ plant protection, Northwestern Agricultural University)
Field demonstration and experiments in 1985-1988 indicated that the optimum period for the application of systemic fungicide,carbendazim or thiop-hanatc-methyl to control to Fusarium head blight of wheat (Fwsarzwm grami-nearum Schw.) was between heading and 5 days after full blossom. The target disease can usually .be controlled by one single application at the optimum period in the irrigated area of Central Shaanxi.The optimum dosages of carbendazim 80% Fine WP and thiophanate-methyl 70% WP recommended were 50g/mu(666,6mz^and 50-70g/mu,respectively.These dosages can be modified based on plant densities,cultivars and severity of infection. The bases for fungicide and formulation selection is in correspondence with their sprayingpatt-erns.Low volume application can save water with high efficiency. Low volume application by power sprayer was 50-70mu per day while that by hand sprayer 15-20mu per day. The effective spraying was 4m in width for the former and 2, 5m in width for the latter. Minimum application rate was 10kg spraying suspension per mu, Large-scale application demonstration indicated that the technique recommended is easy to use, and the results are effectiv e, stable and reliable.