Mutual intercropping affects selenium uptake of eggplant seedlings

To study the effects of mutual intercropping on selenium (Se) accumulation in three different varieties of eggplant (Solanum melongena L.), seedlings of three eggplant varieties (red, green, and black) were intercropped with various combinations in soil containing Se. The seedlings' growth, physiology, and Se accumulation characteristics were compared. The biomass of red eggplant was increased by intercropping with black eggplant and by the three-varieties intercropping treatment. Other treatments decreased or did not significantly affect the biomass of the three eggplant varieties. The contents of photosynthetic pigments (chlorophyll a, chlorophyll b, total chlorophylls, and carotenoids), activities of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase), and soluble protein contents of the three eggplant varieties seedlings almost showed the same trends among the mutual intercropping treatments. Compared with the respective monocultures, intercropping of red and green eggplant increased the Se content in green eggplant seedlings; intercropping of red and black eggplant increased the Se content in black eggplant seedlings; intercropping of green and black eggplant increased the Se content in green eggplant seedlings; and intercropping of all three varieties increased Se contents in red and black eggplant seedlings. The correlation analysis indicated that the Se content had no significant correlation with other items. Therefore, mutual intercropping can promote the Se absorption of eggplant seedlings to some extent, and maybe a useful cultivation strategy for eggplant.