1. When the temperature during the flowering period is very high or continuous rain is predicted, due to the short flowering period, heading and flowering are basically synchronized. At this time, spraying should be done during the full heading period;

2. When the weather during the flowering period is normal and the interval between full heading and flowering is very short, spraying should be carried out when the wheat flowering rate is around 10%;

3. When the temperature during the heading period before flowering is low, the flowering of wheat will slightly slow down, and spraying can be done before and after the peak flowering period of wheat.

It should be noted that due to the short flowering period, spraying during the peak flowering period should be avoided unless necessary. Generally, spraying can be done immediately when the wheat changes from yellow to white flowers, as the white color of the wheat flower indicates the end of wheat pollination. If it is indeed necessary to spray during the blooming period, it is recommended to stagger the pollination time and try not to do it again from 9-11 am, but instead choose to do it from 4-5 pm to greatly reduce the impact on pollination.