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This paper reviewed the research progress on leafy vegetable hydroponics about nutrient solution,environmental factors,cultivation measures and hydroponic domestication.The researches of spinach nutrient solution are mainly focused on the screening of nutrient solution formula and adjustment of main nutrient elements.Light,dissolved oxygen concentration and liquid temperature are main environmental factors influencing spinach growth under hydroponic conditions.Few researches have been conducted on the hydroponic adaptability of spinach.At last,the future research work on spinach hydroponics was also discussed.

The spinach (Spinacia oleracea L.) glycolate oxidase (GLO) gene family members were identified from the whole genome of spinach,and their physical and chemical properties,subcellular localization,gene structure,conserved motifs,homology and gene expression were analyzed.Results showed that there are five SoGLOs proteins in spinach.The genetic relationship between spinach's GLO protein and those of Beta vulgaris L. protein was relatively close through phylogenetic tree analysis.Gene structure analysis revealed that the family gene consisted of 9 to 11 exons.Real-time quantitative polymerase chain reaction (qRT-PCR) showed that nitrate nitrogen could only induce SoGLOs expression in a short period of time,while ammonium nitrogen could continue to inhibit the expression of SoGLOs,thus affecting the content of spinach oxalic acid.After stress treatment,the expression of SoGLOs changed significantly.SoGLO1,SoGLO3 and SoGLO5 responded most to salt stress.SoGLOs may play a role in the salt tolerance,high temperature tolerance,cold tolerance,drought resistance and antioxidant process of spinach.Spraying of phytohormones generally increases the expression of SoGLOs in a short period of time,which may cause rapid accumulation of oxalic acid in spinach.

The classification of the physiological races of spinach (Spinacia oleracea L.) downy mildew (Peronospora effuse) in different regions of China is the basis for screening and identifying of germplasm resources for disease-resistant breeding.In this study,2 pathogens of spinach downy mildew collected from Shanghai were identified and the internal transcribed spacer (ITS) sequence was cloned and analyzed based on ITS primers.The results show that the pathogens of spinach downy mildew collected in Shanghai are race No.9 andare belonged to Peronospora effusa.This study clarified the species of physiological race in Shanghai area,which will provide a reference for spinach downy mildew resistance breeding.

A hydroponic experiment was conducted to study the difference of nitrate accumulation,nitrogen uptake and utilization efficiency between four spinach (Spinacia oleracea L.) genotypes (So10,So13,So18 and So57). Results showed that So13 had the highest nitrate contents under two nitrate (NO3--N) level (0.5 mmol·L-1,15 mmol·L-1) conditions,whereas So10 had the lowest nitrate contents. So18 had the similar nitrate contents with So13 under low NO3- level,while it showed no significant difference of nitrate contents with So57 under high NO3- treatment. The 15NO3--N uptake rates of So13 were the highest one among four genotypes,while the N utilization efficiency (NutE) and N utilization ratio (NUR) of So13 were significantly lower than those of So18 and So57. The shoot dry mass,nitrate reductase activity,NutE,NUR of So18 and So57 were higher than those of So13 and So10,while their 15NO3--N uptake rates were lower than those of So13. The shoot dry mass,nitrate reductase activity,NutE,N utilization ratio of So10 were significantly lower than those of So18 and So57,and its 15NO3--N uptake rate was significantly lower than those of So13. Among the four spinach genotypes,the So57 can be selected as elite germplasm using for spinach production for its relatively lower nitrate content and higher N efficiency.

Anthocyanins are water-soluble pigments,and they play vital roles in many biological functions such as oxidation resistance,preventing and curing many diseases.The purple vegetables accumulate abundant anthocyanins.Its value of scientific research and economic and social benefits of the purple vegetables have become more obvious.In this review,we focused on recent advances regarding the colour related genes and breeding,and proposed a regulation model of anthocyanins biosynthesis in purple vegetables.It will be provide theoretic foundation to further research on anthocyanins biosynthesis and acaumulation,metabolic regulation and control,and genetic improvement of special vegetables.