Saron (Crocus sativus L.) is a highly valuable plant. Iran provides nearly 90% of the world’s total saron and is the biggest global producer. The allelopathic eects of saron corm (SC) and saron field soil (SFS) have been hypothesized to play an important role in replanting. Recently, adsorbent materials have been used to neutralize the eects of allelochemicals. These materials, including activated carbon and zeolite, have large surface areas, pore volumes, as well as tremendous adsorptive capacity and complex chemical and physical properties. In this study, three independent experiments were conducted. In the first test, the allelopathic eects of aqueous and methanolic extracts of SC remnant and 9-year-old SFS as well as filtered aqueous extract of soil were investigated. In the second assay, the eects of SC remnants and SFS with dierent ages (i.e., 4, 6, and 9 years old) in combination with adsorbents were examined on the germination and growth of lettuce (Lactuca sativa L.) seedlings by the sandwich method. In the third experiment, we examined the eects of SC remnants combined with adsorbents on lettuce growth parameters. Our results showed that the allelopathic eects of aqueous and methanolic extracts of SC remnant were significantly superior to those of 9-year-old SFS. The aqueous extract of SC remnant reduced the root length of lettuce by 50%. The use of activated carbon and zeolites significantly decreased the observed allelopathic eect. Moreover, lettuce growth in rhizosphere soil was significantly inhibited by SC remnant and SFS extracts. The allelopathic eects of SC remnants caused a growth imbalance between the shoot and roots. Based on biochemical analyses, using the adsorbents increased the carotenoid content and chlorophyll index of lettuce by 23.33% and 5.25%, respectively. Adsorbents may play a role in treating soils contaminated by allelochemicals.

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