How to prevent and control herbicide damage in yardlong beans? A detailed practical guide

When growing yardlong beans, if management is improper and weeds are plentiful, herbicides must be sprayed to control them. However, if the spraying is done incorrectly and the herbicide lands on the leaves and plants, it will cause herbicide damage to the yardlong beans. In mild cases the leaves dry up; in severe cases the plants die. So how should herbicide damage in yardlong beans be prevented and controlled? Let's take a look.

I. Symptoms

After accidental spraying of herbicide, the old leaves of the yardlong bean first begin to dry up while the stems and vines remain green. However, as the yardlong bean grows, the new leaves become deformed, shrivelled and uneven. If the yardlong bean is at the pod-setting stage at this time, flower and pod drop may also occur, leading to poor plant growth and seriously affecting yield; in severe cases it can also cause premature ageing of the plants.

II. Prevention and control methods

1. Washing with clean water

The period during which herbicides are generally sprayed is about one week; during this period, water should be sprayed frequently on the stems and leaves of the yardlong bean to dilute or wash away the herbicide residue remaining on them, thereby reducing the damage.

2. Timely topdressing

After herbicide damage occurs, topdressing can be carried out promptly to alleviate it. The topdressing is mainly ammonium bicarbonate or urea, and some phosphorus and potassium fertiliser can also be added appropriately. However, the amount of topdressing must be watched: it should be based on the severity of the damage and the growth condition of the yardlong bean, so that excessive topdressing does not affect normal growth and likewise cause a reduction in yield.

3. Water thoroughly

After topdressing, water promptly. This speeds up the release of the fertiliser and its absorption by the plants, lowers the concentration of harmful substances in the yardlong bean plants, and reduces the damage.

4. Foliar feeding

After herbicide damage occurs, use the foliar feeding method to spray the yardlong bean with plant growth regulators and foliar fertiliser, which effectively alleviates the damage. The best effect is achieved by mixing brassinosteroid at 7500 times dilution with foliar fertiliser and spraying the mixture. Generally, depending on the severity of the damage, spray once every ten days to half a month, for 2-3 consecutive times, and the damage can be eliminated.

The above is an introduction to prevention and control techniques for herbicide damage in yardlong beans. We hope it helps you. For more related knowledge, please stay tuned to us.