Tind Tina, Mathiesen Tenna J, Jensen Jens E, Ritz Christian, Streibig Jens C
Danish Agricultural Advisory Service, National Centre, Arhus N, Denmark.
Pest Manag Sci. 2009 Nov;65(11):1257-62. doi: 10.1002/ps.1819.
Grass seed crops are minor crops that cannot support the development of selective herbicides for grass weed control in grass seed crops. An option is to screen for selective herbicides with the use of logarithmic spraying technology. The aim of this paper is to assess selectivity of various herbicides in grass seed crops by using dose-response curves.
Six grass species were subjected to logarithmic spraying with 11 herbicides and with Poa pratensis L. as a weed. The ratio between the doses that caused 10% of damage to the crop and 90% of damage to the weed was used as a selectivity index. Compounds with selectivity indices above 2 can be safely used in a crop. The two ACCase herbicides clodinafop-propargyl and fenoxaprop-P-ethyl and a mixture of the two ALS herbicides mesosulfuron and iodosulfuron could be used selectively to control P. pratensis in Festuca rubra L., although the selectivity indices in no instances were greater than the desired 2.0.
The logarithmic sprayer can be a rapid screening tool for identifying compounds with favourable selectivity indices. Good experimental design is needed to alleviate rates being systematically distributed and confounded with growth rate and soil fertility gradients.
禾本科种子作物是小众作物，无法支持开发用于控制禾本科种子作物中禾本科杂草的选择性除草剂。一种选择是利用对数喷雾技术筛选选择性除草剂。本文旨在通过剂量反应曲线评估各种除草剂在禾本科种子作物中的选择性。
对六种禾本科植物进行了对数喷雾处理，使用了11种除草剂，并以草地早熟禾作为杂草。将导致作物10%损伤的剂量与导致杂草90%损伤的剂量之比用作选择性指数。选择性指数高于2的化合物可在作物中安全使用。两种乙酰辅酶A羧化酶（ACCase）除草剂炔草酯和精恶唑禾草灵，以及两种乙酰乳酸合成酶（ALS）除草剂甲基二磺隆和碘磺隆的混合物，可用于选择性防除紫羊茅中的草地早熟禾，尽管选择性指数在任何情况下都不大于理想的2.0。
对数喷雾器可作为一种快速筛选工具，用于识别具有良好选择性指数的化合物。需要良好的实验设计来减轻速率被系统分布并与生长速率和土壤肥力梯度混淆的情况。
