Non-chemical weed control in an organic wheat crop

摘要

With growing evidence of herbicide resistance and increasing interest in health issues being pursued by an aging population, farmers are looking for alternative methods of both growing crops and controlling weeds. The use of finger tyne harrows and ahigher seeding rate in an organic wheat crop, provides one such method and this was tested in a replicated trial on two soil types. The finger tyne harrows reduced the numbers of all plant groups measured. For a high seeding rate (79 kg ha~(-1) and two passes, the effects were greatest. Broadleaf weeds were reduced from 11 to <1 plants m~(-2) on a heavy soil site and from 91 to 34 plants m~(-2) on a light soil site (P <0.05). Grass weeds were also reduced from 47 to 7 plants m~(-2) on the heavy site (P<0.05) and from 54 to 39 plants m~(-2) on the light site (just not significant). Wheat plant numbers also declined, from 65 to 30 plants m~(-2) on the heavy site and from 86 to 66 plants nr2at the light site (P <0.05). This drop in wheat plant density did not result in a reduction in wheat grain yield. Wheat yields however, were significantly increased at the higher seeding rate on both soil types, without affecting weed numbers.