The fruiting branches with weak growth power will soon stop growing at flowering stage. Even if the flower spikes are preserved, good quality fruits cannot be obtained, so they should be thinned as soon as possible. Thinning is generally carried out at 4 ~ 6 leaves. A fruiting branch generally has two spikes, and in principle, one of them should be thinned out. As long as the development is normal, there is no deformity, and the ear axis is strong, the first ear and the second ear can be left. Generally speaking, weak new shoots leave the first panicle, while strong new shoots leave the second panicle.
in order to obtain grapes with neat and beautiful spike shape and uniform fruit size, it is necessary to shape the flower spike. Removing redundant flower buds can also reduce the waste of nutrients, promote the development of flower buds and reduce the falling of flowers and fruits.
(1) The shaping of the ear when the seed is set. One week before flowering, first cut off the spikelets that affect the spike shape. If the spike shape is affected by excessive elongation, 1 ~ 2 spikelets at the shoulder of the spike can also be thinned out or the top of the spikelets can be removed. If other spikelets are suspected of disturbing the spike shape, only the small flowers at the base are left, and the top part is also removed. If the spike elongation is insufficient and the spikelets are too crowded, some of them can be thinned. About 7 days before flowering, 12 ~ 15 small spikes at the base of the spike are selected.
(2) The seedless seed setting of the whole panicle was mostly obtained by gibberellic acid treatment, and the shape of the panicle was different from that of the seedless seed setting. There are also differences in heading methods among different varieties. For varieties with giant peaks such as Xianfeng, firstly, the spikelets should be thinned as soon as possible one week before flowering, and the oversized spikelets on the shoulders should also be thinned as soon as possible. From 3 days before flowering to the day of flowering, the length of the top of the spike is 3 ~ 3.5 cm, and the rest are all thinned. In the middle and upper part of the spike, two spikelets can be left as identification marks. When seedless treatment and fruit grain expansion treatment are carried out, one spikelet is removed at a time to avoid omission or repeated treatment. For varieties such as Bud Rose, spike shaping is carried out around 16-2 days before blooming. First, a small number of florets at the tip of the spike are cut off, and 12-14 spikelets are selected from the spike tip to the base. After that, 2 spikelets on the upper florets are left as signs of seedless treatment and fruit grain expansion treatment, and the rest spikelets are all thinned out.