Fruit growth, carbon allocation, and related enzymes in tomato under different irrigation and potassium application regimes

Background The increasing concentration of atmospheric CO2 not only affects the growing environment crops but also aggravates global greenhouse effect and further problem water shortage. combined deficit potassium (K) application has been widely studied. Aims A pot experiment was conducted to investigate irrigation (DI) K at different growth stages on carbon allocation enzyme activities related sugar metabolism. Methods Tomatoes were transplanted planted April 26, 2017 harvested August 15, 2017. Four regimes implemented with two levels (full irrigation-W DI-W/2) in stages, each treatment equally divided into subgroups: (K1) without (K0). Fruits from first fourth trusses tomato plants sampled. Tomato growth, allocation, measured. Results fresh weight (FW), dry weight, relative rate mass sensitive amount under fertilization, enhancing promotion fruit. Meanwhile, regime. Sucrose synthase (SuSy), acid invertase (AI), sucrose phosphate (SPS) highly condition. Starch phosphorylase displayed a quadratic parabola for amount, adenosine diphosphate glucose pyrophosphorylase (AGPase) fertilization. Carbon form other carbohydrates, soluble (Csol), fruit content factors that had greatest influence principal components. Classification by K-means algorithm canonical correlation analysis showed FW, fructose, sucrose, starch could be used as significant indicators matter components K. In case regime, SuSy, AGPase, AI, Csol indicator metabolism activity. Conclusions improvement quality deficient explored. Water stress changed distribution photosynthetic between sugar. balance sugars compounds. particular, it significantly increased decreased AI SuSy are key enzymes affecting water-deficient conditions.