Why Are Pear Tree Leaves Turning Yellow? Latest Cause Analysis
Pear trees are basically cultivated in all parts of our country, and the economic value of pear trees is relatively high. When we plant pear trees, we inevitably encounter some problems that affect the growth of pear trees. Among these, yellowing of pear tree leaves is one of them. Yellowing of pear tree leaves will affect the photosynthesis of pear trees, leading to a decline in nutrient accumulation and affecting pear fruit quality and yield. So why are pear tree leaves turning yellow? Let's take a look together with the editor below!
1. Insufficient Light
When planting pear trees, if yellow leaves appear on the pear tree before autumn, then it is very likely caused by a lack of light. If pear trees lack light, the leaves cannot carry out photosynthesis, which leads to a decrease in chlorophyll content in the leaves and gradually causes yellow leaves. Therefore, when planting pear trees, we must pay attention to maintaining sufficient light. We should promptly prune overly long and dense branches to improve the ventilation and light penetration inside the pear tree canopy, maintain good light transmission, so that branches inside the canopy can also receive sufficient light and reduce yellow leaves.
2. Soil Too Alkaline
If the soil for planting pear trees is too alkaline, then it is also very likely to cause yellow leaf disease in pear trees. In many cases, in plots where pear tree yellow leaf disease occurs, the soil pH is generally not lower than 8. This causes the soil to become too compacted, the concentration of ferrous ions in the soil to be relatively low, and the calcium content in the soil to be too high. A antagonistic effect occurs between the ions. This further inhibits the absorption of iron by pear trees, resulting in a lack of iron catalytic enzymes when the pear tree synthesizes chlorophyll, inability to normally form chlorophyll, and the appearance of yellow leaves.
3. Nutrient Deficiency
Nutrient deficiency is one of the main causes of yellow leaves in pear trees. Different deficiency symptoms produce different yellow leaf phenomena. First, if there is a nitrogen deficiency, then the leaf shape of the pear tree will gradually shrink, and the leaves will be mainly yellow-green. It starts from the lower leaves of the plant and slowly spreads upward, eventually causing the whole leaf to become pale yellow, and in severe cases the pear tree will die. Then there is phosphorus deficiency. If the pear tree lacks phosphorus, the leaf color will gradually darken, then slowly turn purplish-yellow. If it lacks potassium, yellowing starts from the tips and edges of old leaves, and then the leaves gradually wither and necrose.
Iron deficiency is the most common nutrient deficiency that causes yellow leaves in pear trees. If the pear tree lacks iron, the areas between the veins will gradually lose green and turn yellow, but the veins will not be affected. This is also the most common yellow leaf phenomenon in pear trees. Then, if there is a magnesium deficiency, the yellow leaf phenomenon is mainly manifested on old leaves, similar to iron deficiency. Calcium deficiency, however, is the opposite of magnesium deficiency. The yellow leaves are mainly manifested on new leaves. The leaves will gradually turn yellow from the outside inward, but the veins remain green, and the leaf edges will gradually curl downward. In addition, deficiencies in manganese, zinc, sulfur, boron, and others can all cause yellow leaves in pear trees.
The above is a brief introduction to why pear tree leaves turn yellow. That is all for today's introduction. This article is for reference only, and I hope it can help everyone!