What does scab disease look like on guava fruit, and what medicine is used for guava scab disease

What do the symptoms of guava scab disease look like, and how should it be treated, do you know? Let us take a look together.    

Symptoms: When initially infected, the lesions are round and slightly raised, and the surface of the lesions is rough with cracks, like scab, brown, with the edges a light brown or earthy yellow color, about 2 to 4 mm in size. In the center of the lesion there are small black ring-shaped dots, and from the top of the small black dots black powder or curved columnar bodies are released, which are the pycnidia and pycnidiospores of the pathogen. When the lesion sinks, the epidermis at the edge separates from the tissue of the healthy part, and the lesion does not fall off.

        Two kinds of symptoms appear in the flesh tissue: one is softening of the flesh, water-soaked, with the flesh color turning orange-yellow or purple-yellow; the second is corky yellow-brown flesh, which does not soften or become water-soaked, often accompanied by calcium deficiency in the fruit. When calcium is deficient, browning appears on the epidermis near the outer side of the center of the fruit, gradually forming a transverse band area or a ring spot, and the fruit therefore weakens and ages prematurely.

        The Thai guava strain has extremely strong growth vigor, and the fruit tree has no juvenile stage, so it will bloom and bear fruit in the first year of planting. Therefore, the upward leggy branches have extremely strong growth vigor, and the fruit borne on the leggy branches often shows blossom end rot, with symptoms appearing as transverse band browning or browning at the bottom of the fruit, which is closely related to the occurrence and infection of various weak pathogens.

Control methods:

1. Prune branches at the right time to keep the orchard well ventilated and avoid planting fruit trees too densely; do not mix-plant other fruit trees, reduce intermediate hosts, all of which help in the control of scab disease.

2. For field sanitation, pick out diseased fruit and burn diseased leaves or branches to eliminate the pathogen.

3. Avoid repeatedly using old packaging bags for fruit bagging. Bagging small fruit for protection has a good control effect, but some fruit growers, because of thrifty habits, often reuse bags, which makes them prone to scab disease infection.
Now that you have learned both the symptoms and the control methods, you know what to do now, right?