| To explore the effects of temperature on the flower bud differentiation of Physalis pubescens L., this study took the‘Dahuang guniang’Physalis pubescens variety as the experimental material. Different temperature treatments at the flower bud differentiation stage of 27℃/20℃ (CK), 23℃/16℃ (T1), 31℃/24℃ (T2) and 35℃/28℃ (T3) were used to study the morphological differentiation process of Physalis pubescens flower bud and the changes of endogenous hormones, carbohydrates, antioxidant enzymes and other physiological indicators during the flower bud differentiation process. The results showed that the process of flower bud differentiation of Physalis pubescens was the same under low temperature treatment (T1) and CK treatment. The initiation time of flower bud differentiation of high temperature treatment (T2 and T3) was not only earlier than CK, but also earlier than CK to complete the process of flower bud differentiation. The sepal primordium differentiation under high temperature treatment could not form a closed sleeve structure, and the fruit was exposed outside the persistent calyx in the later stage. The fruits of CK and T1 were normal, but the proportion of deformed fruit reached 50% and above under high temperature treatment. Total nitrogen content of different treatments showed T3＜T2＜CK＜T1 in the 3L stage. However, the total nitrogen content of T2 and T3 treatments was 30.7% and 40.1% lower than CK in the 3L stage, respectively. The activity of CAT showed a trend of first increasing and then decreasing and reached the highest value with T3>T2>CK>T1 in the 3L stage. The SOD activity under high temperature treatment showed a trend of first decreasing and then increasing, and at the 4L stage, the SOD activity was 24.5% and 25.9% higher than CK, respectively. Under the higher temperature treatments, the POD activity showed a trend of first increasing and then decreasing, and compared with CK, with the effect order of T3>T2>CK. As the differentiation process progresses, the content of ABA, IAA, ZR, and GA3 reaches its highest value at the 3L stage under high temperature treatment, while the highest value is only reached at the 4L stage under low temperature and CK treatment. During the 3L stage of high\|temperature treatment, the IAA content was 31.5% and 62.5% higher than CK, and the GA3 content was 107.4% and 87.9% higher than CK, respectively. The ABA/IAA, ZR/IAA ratios of T2 and T3 were lower than those of CK, with T2, T33 ratio of T1 treatment was higher than the other three treatments during the differentiation process of hairy acid pulp flower buds and was 24.1%~37.8% higher compared to CK, respectively. The soluble sugar and fructose of Physalis pubescens were accumulated under CK treatment in 3L stage, in which that soluble sugar was 75.8%, 33.6%, and 16.8% higher than T1~T3, respectively. Therefore, different temperature treatments affected the flower bud differentiation of Physalis pubescens. Higher temperature promoted hormone synthesis, affected nitrogen content and the accumulation of soluble sugar and fructose, regulated the activity of antioxidant enzymes, and promoted the flower bud differentiation of Physalis pubescens, but led to the formation of abnormal fruit. |