Key Management Techniques During the Apple Flower Bud Differentiation Period

The flower bud differentiation period refers to the process in which the terminal buds and lateral buds of fruit trees turn into flower buds, and flower bud differentiation is the foundation of apple flowering and fruiting, as well as the turning point from vegetative growth to reproductive growth. This is related to the quality of apple flowering and fruiting and the later yield. So how should management be carried out during the apple flower bud differentiation period? Follow the editor to take a look.

I. Timing of Apple Flower Bud Differentiation

1. Physiological differentiation period: When new shoots of the fruit tree stop growing, or from the beginning when most short branches stop growing until most long branches stop growing, the period between these times is called the physiological differentiation period. It begins as early as late May, reaches its peak in June to July, and can continue until September to October. This is the key to controlling flower bud differentiation.

2. Morphological differentiation period: At this time, various floral organs are formed through differentiation within the buds, generally from June to September after new shoots stop growing. The number of flower buds that differentiate is closely related to the growth amount of new shoots and how early or late the new shoots stop growing.

3. Sexual cell differentiation period: This refers to the period from dormancy to before flowering, mainly the differentiation and development of pollen and ovules, and is closely related to the fruit setting rate.

II. Conditions for Apple Flower Bud Differentiation

Only when the growth of young buds is in an active yet not overly vigorous branch state can flower bud differentiation proceed, while inactive young buds cannot undergo flower bud differentiation. If the growing point is too active, it will cause new shoot growth without forming flower buds, while as the buds become inactive, they cannot form flowers either. When the apple tree has sufficient nutrient accumulation, this is extremely favorable for flower bud differentiation. The suitable temperature for apple flower bud differentiation is above 20 degrees. In addition, strong light and sunlight are also favorable for flower bud differentiation. Before the critical period of flower bud differentiation, short-term water control to inhibit new shoot growth is favorable for flower bud differentiation.

III. Management Techniques for Apple Flower Bud Differentiation

In the early stage, promote the growth of branches and leaves of the fruit tree and pay attention to fertilizer and water management, as this is favorable for the accumulation of photosynthetic products. Fruiting trees can be fertilized before the critical period, mainly with phosphorus and potassium fertilizers, controlling the application of nitrogen fertilizer, and at the same time controlling water by humidity, but it should not be too dry. This is favorable for flower bud formation. Some agents that promote flower bud differentiation can also be sprayed to inhibit the growth of new shoots and secondary shoots on fruit spurs, accelerate the nutrient accumulation of branches, and promote flower bud differentiation. In addition, inhibiting the excessive growth of autumn shoots will also promote flower bud differentiation in fruit trees. The simplest method is to spray growth regulators for control, which can be sprayed once in May to June, mainly targeting young leaves of new shoots. For fruit trees with vigorous growth or heavy fruiting, another spray can be applied in July as appropriate. At the same time, pruning during the growing period should be strengthened to promote the development of medium and short branches. Growing-period pruning is mainly carried out on vigorously growing young trees, with light pruning as the main approach and balancing tree vigor.

The above is an introduction to management techniques during the apple flower bud differentiation period. We hope it can help you. To learn more related knowledge, please follow us.