Abstract:

 In order to research the effect of deficit irrigation on post-harvest quality of cut chrysanthemums, the variety "Shenma" was selected for testing, different irrigation treatments. Referring to the reference evapotranspiration (ET₀) of fresh-cut chrysanthemums, four irrigation treatments, T1 (90% ET₀), T2 (75% ET₀), T3 (50% ET₀), and CK (100% ET₀) were established. A field experiment was conducted in a solar greenhouse at Nanjing Information Engineering University. The flower diameter, fresh weight, water balance value, and lifespan of the fresh-cut chrysanthemums were measured, and the impact of the deficit irrigation treatments on the appearance quality of the fresh-cut chrysanthemums was investigated. The findings indicate that: (1) the moderate deficit irrigation (T2) results in the longest vase life of the fresh-cut chrysanthemums, while the severe deficit irrigation (T3) results in the shortest vase life. (2) The moderate deficit treatment (T2) results in the largest increase in flower diameter, while the severe deficit irrigation (T3) results in the smallest reduction in flower diameter and the fastest wilting rate. (3) The mild deficit irrigation (T1) allows the fresh-cut chrysanthemums to maintain a significant fresh weight. (4) The moderate deficit irrigation (T2) maintains a higher water balance value for the fresh-cut chrysanthemums after vase planting and at the end of their lifespan. Treatment (T2) significantly prolongs the vase life of cut chrysanthemums, increases flower diameter, and enhances water balance value. It has good water retention and appearance quality, and is highly ornamental. Treatment T2 is the optimal irrigation amount for fresh cut chrysanthemums in Nanjing region．

Key words: Deficit irrigation, Cut chrysanthemum, Flower diameter, Fresh weight, Vase life