Abstract:

In the warm, humid, and rainy growing season of pear trees in southern China, especially during the continuous overcast and rainy days of the plum rain season, pear orchards experience prolonged waterlogging. This leads to persistently high soil moisture levels, reduced soil porosity, and insufficient oxygen content, resulting in anaerobic stress for the pear tree roots, impaired respiration, decreased mineral nutrient absorption capacity, and inadequate above-ground nourishment. As a result, leaf yellowing occurs along with growth inhibition, ultimately reducing fruit yield and quality. To analyze the effect of waterlogging on the nutrient uptake of pear trees, mineral element content was measured and comparatively analyzed in the leaves of pear trees from waterlogged orchards, including both tolerant and sensitive types, as well as from non-waterlogged orchards. Additionally, the mineral element content in the root zone soil of waterlogged and non-waterlogged pear orchards was also measured and compared. The results showed that under waterlogging stress, the nitrogen and manganese contents in the leaves of waterlogging sensitive pear trees were significantly (p<0.05) lower than those of waterlogging tolerant pear trees and non-waterlogged pear trees, but the potassium and boron contents were significantly increased. There was no corresponding relationship between the difference in mineral element content of pear leaves and the difference in mineral element content of root zone soil between pear orchards affected by waterlogging and those without waterlogging. Spraying mancozeb can significantly increase the manganese content in the pear leaves affected by waterlogging.

Key words: environmental stress, waterlogging, mineral element, pear tree