The insight of storage root formation mechanism under different soil compaction which is one of the vital factors affecting storage rot yield is crucial for the high and stable storage yield of sweet potato (Ipomoea batatas L.). Photosynthetic characters has been proved to be determining factor of crop yield. So field experiments were conducted with 2 varieties in control, loose, and compacted soil conditions, canopy apparent photosynthesis, gas exchange parameters and chlorophyll fluorescence parameters of the functional leaves, storage root yield were determined, and the relationship between yield and photosynthetic characters was studied as well. The results indicated compared to the control, the storage root yield was significantly increased in loose soil with the average increase of 27.03%~38.74%, but decreased in compacted soil with the average reduction of 17.87%~15.92%. The CAP got the similar change law. Loose soil also improved gas exchange parameters of functional leaves, overall performance and donor/recipient side properties of PSII, the reverse was found in compacted soil. The CAP was significantly positively correlated with storage root yield (r= 0.99, P<0.05) and single storage root weight (r= 0.90, P<0.05). As per statistical path analysis, the net photosynthetic rate (Pn) had the most total effect and higher direct effect on increasing CAP. That is, reduce the soil compaction increased Pn of functional leaves, brought higher CAP, resulted in high storage root yield.
Article Type:
Original Research |
Subject:
Landscape Horticulture Received: 2023/10/9 | Accepted: 2024/01/1