From continuous-cropping years and the annual pathogen growth rate, estimate soil pathogen accumulation and the continuous-cropping obstacle risk level.
| Item | Formula / Note | Source / Standard |
|---|---|---|
| Continuous cropping obstacle index | CI = Y_actual/Y_normal × 100 | Yu Jingquan group review, Zhejiang Univ. |
| Pathogen accumulation | P = P0(1+r)^n | soil-borne disease models |
| Rotation interval | Same family ≥2-3 yr gap | NY/T 391-2021 |
连作障碍指数估算工具,基于连作年限、初始病原菌密度与年增长率,采用指数增长模型估算土壤病原菌积累程度,并对照阈值密度计算连作障碍指数与风险等级,辅助连作风险评估与轮作决策。