Experiment on optimal irrigation control indicators for greenhouse tomatoes based on soil moisture threshold
In arid and semi-arid regions,the scarcity of water resources represents a significant challenge to agricultural development.The demand for water during different stages of crop growth and development varies,necessitating the identification of lower limit irrigation indexes for each reproductive period.This approach provides a scientific foundation for the establishment of optimal irrigation control indexes in arid and semi-arid areas,facilitating the advancement of greenhouse-based agriculture.In this experiment,greenhouse tomato was used as the research object,and a field experiment was carried out in Helan County,Ningxia.Three key water control periods were set up(the lower limits of irrigation at each growth stage were 60％,65％and 70％of the field moisture capacity(θf),and the seedling stage was uniformly set to 55％of the field moisture capacity),and a total of 7 water treatments were established to investigate the impact of varying lower limits of water during each fertility period on the growth,biomass,yield,and quality of greenhouse tomato.The entropy-weighted TOPSIS comprehensive evaluation method was utilized to optimize a reasonable lower limit of soil moisture control in each fertility period of greenhouse tomato.The field experiment demonstrated that the trends in plant height,stem thickness,and the average number of nodes under different treatments were consistent.The T4 treatment(which maintained the lower limit of water control at 55％,65％,65％,70％,and 65％during each fertility period)exhibited the greatest average daily growth in plant height,reaching a maximum value of 230 cm by mid-November,with an average daily growth rate of 2.58 cm/d;The T2 treatment(which maintained the lower limit of water control at 55％,60％,70％,65％,and 65％during each fertility period)exhibited the largest stem thickness of 13.39 mm,The T3 treatment(which maintained the lower limit of water control at 55％,70％,70％,65％,and 65％during each fertility period)the greatest average daily increase in stem thickness,at 0.13 mm per day.Leaf area index(LAI)increased and then decreased during the reproductive period,with the T3 treatment being the largest at 4.43.The dry weight of the entire plant exhibited a range of 101.74 g to 161.01 g during the flowering stage and a range of 147.27 g to 203.92 g during the fruiting stage.The control treatment(CK)exhibited the highest dry weight,with values of 161.01 g and 203.92 g,respectively;The yield ranking analysis indicated that the yield was larger when the lower limit of soil moisture was higher during the fruiting bloom period,T,(which maintained the lower limit of water control at 55％,65％,60％,70％,and 65％during each fertility period)had the highest yield of 35.58 t/hm2,which was 36.7％higher than the control.The quality of the tomatoes produced in the greenhouse was superior when the lower limit of irrigation during the fruiting bloom period was set at 65％to 70％,the T2 treatment exhibited the highest soluble sugar content,at 8.61％,while the T3 treatment demonstrated the highest lycopene content,at 4.40 mg/(100 g).The comprehensive analysis indicated that the appropriate lower limit of irrigation could lead to higher yield,and the appropriate lower limits of soil water control for tomatoes in different growth stages of autumn delayed cropping facilities were as follows:the seedling stage,the flowering and fruiting stage,the early fruiting stage,the peak fruiting stage,and the late fruiting stage were 55％θf(where θf represents the field water-holding rate),70％θf,60％θf,65％θf,and 65％θf,respectively.The findings of this study may inform the development of optimal and practical irrigation strategies for the cultivation of tomatoes in facilities,thereby providing scientific evidence to support the advancement of local greenhouse agriculture.
greenhouse tomatosoil moisture control lower limitentropy-weight TOPSISdry matterquality
万方数据
维普
