Abstract:

In order to explore the effects of canopy shading on agronomic traits, yield and quality of Isatis indigotica under intercropping with jujube, field experiments were conducted with four different canopy shading treatments, including 1 m from the central stem of the eastern jujube tree, 2.75 m from the central stem of the eastern jujube tree, 2.75 m from the central stem of the western jujube tree, and 1 m from the central stem of the western jujube tree. The results showed that canopy shading had a significant effect on the agronomic traits of I. indigotica. The number of leaves, dry and fresh weight of leaves, leaf drying rate, main root diameter and root drying rate of I. indigotica near the jujube tree increased significantly, while the main root length, fin number and root drying rate did not change significantly, indicating that canopy shading could promote the individual growth of I. indigotica. Canopy shading had a great effect on the dry and fresh yield of the leaves and I. indigotica. The dry and fresh yield of the leaves and I. indigotica far from the jujube tree in the east was relatively high, while those far from the jujube tree in the west was relatively low. The content of I. indigotica (R,S)-goitrin were higher in the leaves near jujube tree. The results showed that canopy shading under intercropping with I. indigotica and jujube tree can promote individual growth of I. indigotica, reduce the content of indirubin in leaves and increase (R,S)-goitrin content in I. indigotica.

Key words: jujube, intercropping, Isatis indigotica, canopy shading, agronomic traits, yield, quality