High temperature (HT) is becoming an increasingly serious factor in limiting crop production with global climate change. During hot seasons, owing to prevailing HT, cultivated tomatoes are prone to exhibiting stigma exsertion, which hampers pollination and causes fruit set failure. However, the underlying regulatory mechanisms of the HT-induced stigma exsertion remain largely unknown. Here, we demonstrate that stigma exsertion induced by HT in cultivated tomato is caused by more seriously shortened stamens than pistils, which is different from the stigma exsertion observed in wild tomato species. Under the HT condition, the different responses of pectin, sugar, expansin, and cyclin cause cell wall remodelling and differentially localized cell division and selective cell enlargement, which further determine the lengths of stamens and pistils. In addition, auxin and jasmonate (JA) are implicated in regulating cell division and cell expansion in stamens and pistils, and exogenous JA instead of auxin treatment can effectively rescue tomato stigma exsertion through regulating the JA/COI1 signalling pathway. Our findings provide a better understanding of stigma exsertions under the HT condition in tomato and uncover a new function of JA in improving plant abiotic stress tolerance.

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Plant height is a key agronomic trait regulated by several phytohormones like gibberellins (GAs) and auxin. However, little is known about how cytokinin (CK) participates in this process. Here, we report that SlRR6, a type-A response regulator in CK signaling pathway, positively regulates plant height in tomato. SlRR6 was induced by exogenous kinetin and GA3, but inhibited by indole-3-acetic acid (IAA). Knockout of SlRR6 reduced tomato plant height through shortening internode length, while overexpression of SlRR6 caused higher plant due to increased internode number. Cytological observation of longitudinal stems showed that both knockout and overexpression of SlRR6 generated larger cells, but significantly reduced cell numbers in each internode. Further studies demonstrated that overexpression of SlRR6 enhanced GA accumulation and lowered IAA content, along with expression changes in GA- and IAA-related genes. Exogenous paclobutrazol and IAA treatments restored the increased plant height phenotype in SlRR6-overexpressing lines. Yeast two-hybrid, bimolecular fluorescence complementation and co-immunoprecipitation assays showed that SlRR6 interacts with a small auxin up RNA protein SlSAUR58. Moreover, SlSAUR58-overexpressing plants were dwarf with decreased internode length. Overall, our findings establish SlRR6 as a vital component in the CK signaling, GA, and IAA regulatory network that controls plant height.

The core of building energy allocation is to reduce the power load and power consumption through the reasonable allocation of energy equipment, so as to reduce the capacity of the supply side and save investment. In this way, the configuration of energy schemes in data center is conducted in this paper. According to the results of load forecasting, the energy supply scheme of each building in the planning area is determined, including ground source heat pump (GSHP) system, solar water heating system and heat pipe air conditioning system. In addition, feasibility analysis and economic analysis of each configuration scheme are carried out, and the relatively reasonable scheme is selected. It is found that GSHP system can be used in canteen building, solar hot water system can be used as auxiliary for apartment buildings and joint operation of heat pipe air conditioning unit and traditional machine room air conditioning unit is the most economical for data room. Through the research of this paper, a feasible method for the reasonable allocation of energy is provided in the data center planning stage.