Study On The Optimal Row Spacing Collocation And Irrigation Amount Of Greenhouse Tomato With Furrow Irrigation Under Film

Greenhouse tomato in northwest China is usually planted with wide-narrow row planting form and irrigated by furrow irrigation under film.The width is used as the operation line,while the narrow is used as the irrigation line.The wide and narrow line are arranged alternately.This model is not only convenient for field management in the middle and late stage of crops,but also for improving the ventilation and light transmission conditions of crops.But during the production of greenhouse tomato,there is no uniform standard for row spacing,and the irrigation amount is determined by subjective experience.It has become an important factor that restricts the quality,yield and efficiency of greenhouse tomato in this area.Therefore,It is of far-reaching significance to study reasonable row spacing collocation and scientific irrigation amount for the development of greenhouse tomato industry in this area.This study used the greenhouse field experiment,setting up three row spacing collocation S1(80 cm+60 cm)?S2(95 cm+45 cm)?S3(110 cm+30 cm)and three irrigation levels K1(0.50E),K2(0.75E),K3(1.00E)according to cumulative evaporation,studying the effects of different row spacing collocation and irrigation amount on the growth,physiology,quality,yield and irrigation water use efficiency of greenhouse tomato.The main conclusions were as follows:(1)Row spacing collocation,irrigation amount and the interaction of the two factors had effects on the growth of tomato root and crown.There was no obvious correlation between the crown and root growth index,indicating that the single tomato root growth index could not dominate the growth of the crown.Similarly the single tomato crown growth index could not decide the growth of the root.(2)There was an interaction between crown and root growth of tomato,and the growth of the crown and the root was more consistent with different treatments,which the root and crown growth of tomato treated with S3K2 were the best,while S1K1 were the worst.The growth of tomato crown and underground roots increased with the increase of irrigation amount at the interval of S1 and S2,while in the S3 row spacing collocation,the growth of tomato crown and underground roots was first increased and then decreased with the increase of irrigation amount.(3)The chlorophyll content of tomato leaves increased first and then decreased with the growth period,and reached the maximum in the fruit enlargement period.The differences of chlorophyll content in the leaves with different treatments mainly occurred in the fruit enlargement period and the early stage of mature period.The chlorophyll content decreased with the decrease of irrigation amount under the same row spacing and the variation of chlorophyll content in the same irrigation amount was S3>S2>S1.Photosynthesis was enhanced with the increase of irrigation amount in S1 and S2 row spacing,while increased first and then decreased with the increase of irrigation amount in S3 row spacing.Net photosynthetic rate and transpiration rate were closely related to stomatal conductance.Intercellular CO2 concentration and stomatal conductance showed the same trend,indicating that the photosynthesis of tomato was mainly restricted by stomatal factors.Fv/Fm reached maximum in fruit enlargement stage.Different row spacing collocation and irrigation amount had obvious effects on Fv/Fm and qP in the late growth stage,while the changing tendency of NPQ was contrary.(4)S1 compared with S2,S3 could increase the fruit weight and reduce the variation coefficient of transverse diameter,so as to improve the appearance quality of tomato.S1 and S2 compared with S3 could improve the acceptability and VC content of tomato fruits,thereby improving the taste and nutritional quality of tomato.The decrease of irrigation amount could reduce fruit weight and not conducive to the appearance of tomato quality,however the taste quality of tomato(soluble solids,taste acceptance)would increase with the decrease of irrigation amount.The changes of two nutrient quality indexes of VC and lycopene were different with the irrigation water trend,and the maximum value of VC was obtained at the maximum irrigation amount(K3),while the maximum value of lycopene was obtained at the lowest irrigation amount(K1).(5)The result of comprehensive evaluation of tomato quality by principal component analysis and gray correlation analysis showed that S1K1 was the best treatment,and S3K3 was the worst.Using the TOPSIS method to integrate principal component analysis and gray correlation analysis results obtained the comprehensive quality ranking of tomato with different row spacing collocation and irrigation: S1K1>S2K1>S3K1>S1K3>S2K3>S2K2> S1K2>S3K2>S3K3.(6)The total yield of S1K3 and S3K2 were the largest,and S1K2,S2K3,S3K3 less,S1K1,S2K1,S2K2 and S3K1 minimum.IWUE was significantly increased with the decrease of irrigation amount under three kinds of row spacing collocation.The analysis of yield distribution of each panicle fruit showed that the main reason for the high yield of S1K3 and S3K2 was that the yield was not significantly lower.The analysis of fruit yield distribution in each region showed that the yield was the largest in 125 g ? w <250 g,and the total output was also affected by the yield.The correlation analysis showed that there was a positive correlation between root and crown growth and total yield and the better growth of root and crown could bring the higher yield.The net photosynthetic rate(Pn)and transpiration rate(Tr)of tomato leaves were significantly positively correlated with the total yield of tomato,and the Pn and Tr in the fruit expanding period could be used as the indexes to predict tomato yield.(7)Taking the best quality as the goal and combining irrigation water use efficiency,S1K1 was the optimal combination of row spacing collocation and irrigation amount.Taking the highest yield as the goal and combining with the irrigation water use efficiency,S3K2 was the optimal combination of row spacing collocation and irrigation amount.When the yield and quality were better,S1K3 was the best combination of row spacing collocation and irrigation amount.