1, there is a problem with the root system of pineapple. This leads to stuffy roots, stagnant water and rotten roots. According to the root system seen, combined with the watering situation, mix soil matrix to find out the reasons for stuffy roots, stagnant water and rotten roots.

2. The disease of yellow pineapple is mainly rust. Symptoms at the early stage of onset, yellow-green spots with nearly round edges appeared on the leaves, and orange-yellow microprotrusion and small blister spots appeared on the back of the leaves at the later stage of onset. After the blister spots burst, orange-yellow summer spores were scattered, and the diseased spots on the leaves increased and the leaves died.

3. Insect pests. There are mainly Papilio Papilio, aphids, slugs, etc., which mainly harm leaves, leading to weak plant growth, yellow leaves and withered branches, until the whole plant dies.