Abstract:

The study aims to explore the effect of grass growing between rows on the microenvironment and fruit quality in Korla Fragrant Pear orchards, and to provide a theoretical basis for the promotion and application of grass growing technology in orchards in arid desert areas of Northwest China. In this study, a comparative treatment of grass growing and clean tillage was set up in the Korla Fragrant Pear orchard in the core production area of Korla Fragrant Pear. The temperature and humidity of the microenvironment of the lower, middle and upper layers of the canopy were monitored at fixed points throughout the year, and its impact on the orchard microenvironment and fruit quality was comprehensively analyzed. The results showed that: in terms of micro climate, grass growing treatment showed significant temperature and humidity buffering effect. Compared with clean tillage, the monthly average temperature of each canopy in the grass growing area was generally lower, and the temperature difference between treatments decreased with the increase of canopy, reflecting its stabilizing effect on the near-ground microclimate. The grass growing treatment can effectively reduce the temperature fluctuation in the middle and lower layers in winter, spring and summer, especially in the middle layer, with the temperature difference decreases by 13.36%-16.50%. At the same time, the grass growing treatment generally increased the relative humidity in the garden and significantly enhanced the humidity stability of each canopy (especially the middle and lower layers). The humidity difference in the lower layer decreased by 18.25% in winter, and that in the middle layer decreased by 14.81% in summer. In terms of fruit quality, the grass growing treatment significantly improved the comprehensive quality of Korla Fragrant Pear. In terms of appearance index, the single fruit weight was significantly increased by 19.23%, the fruit shape was effectively improved (the skew index was reduced by 18.75%) and the fruit hardness was reduced. In terms of internal indicators, the soluble sugar, sugar acid ratio and vitamin C content of grass growing treatment increased significantly by 4.16%, 8.48% and 8.75%, while the titratable acid content increased significantly by 8.70%, and the total polyphenols and total anthocyanins increased significantly by 135.27% and 40.82%, respectively. The inter row grass growing technology can effectively enhance the stability of temperature and humidity by improving the near ground microenvironment of Korla Fragrant Pear orchard, thus significantly improving fruit quality.

Key words: grass growing, Korla Fragrant Pear, temperature, relative humidity, fruit quality