Effect Of Cultivation Mode On Growth And Soil Biologic Characteristic Of Cucumber And Tomato In Greenhouse

Continuous cropping is universal problem in sun-greenhouse vegetable production;it brought continuous cropping barrier, decreased vegetable yield and quality, aggravated diseases and insect pests and soil salinization. This paper dealt with the effect of continuous cropping years, different cropping on growth, and soil biologic characteristic of cucumber and tomato. The result showed main nutrient in soil of cucumber and tomato increased, increased extent in soil organize matter, total N, total P and avail P were bigger, soil pH declined with continuous cropping year increasing.Salinity content, NO₃^- -N content and electric conductivity in soil of cucumber and tomato enhanced with continuous cropping years increasing. Compared with CK and continuous cropping 4 years cucumber, soil salinity content of continuous cropping 11 years cucumber increased 305.1% and 78.8%, soil electric conductivity enhanced 0.632ms/cm and 0.577ms/cm, soil NO₃^- -N content enhanced 39.637mg/kg and 18.84mg/kg. Compared with continuous cropping tomato 2 years and 4 years, soil salinity content of continuous cropping 8 years tomato enhanced 169.03% and 46.15%, soil electric conductivity enhanced 168.75ms/cm and 84.94ms/cm, soil NO₃^- -N content enhanced 96.21mg/kg and 69.95mg/kg.Continuous cropping influenced on the growth and development of cucumber and tomato. The plant height, stem thickness, leaf number, leaf area and fruition rate of cucumber of continuous cropping 4 years were the highest, and continuous cropping 11 years were the lowest. Cucumber yield of continuous cropping 4 years was 2.17kg/plant, ck was 1.78kg/plant, continuous cropping 11 years was 1.50kg/plant. Content of Vc and dissolubility substance in fruit of cucumber of continuous cropping 4 years were higher than ck, ck was higher than continuous cropping 11 years. Physiological disease of continuous cropping 11 years increased 245.6% and 40.3% than ck and continuous cropping 4 years.With continuous cropping years increasing, plant height, stem thickness, leaf number, fruition rate and yield of tomato decreased obviously, its abnormality fruit rate, and incidence of a disease increased obviously. Total acidity, Vc, dissolubility matter, nitrite in tomato fruit of continuous cropping 2 years was higher than four years, 4 years was higher than 8 years. Nitrate in tomato fruit of continuous cropping 8 years was higher than 2 years and 4 years. Dissolubility sugar, sugar over acid in tomato fruit of continuous cropping four years was greater than two year, two years was greater than eight years. After continuous cropping twoyears, the physiological barrier of tomato was occurred obviously.Catalase and sucrase activity in soil of cucumber of continuous cropping 4 years were bigger than 11 years, 11 years were bigger than ck. Phosphatase and urease activity in soil of continuous cropping 11 years were bigger than 4 years, 4 years were bigger than ck. As continuous cropping years increasing, numbers of soil bacteria and fungi increased, numbers of soil actinomycete decreased.With continuous cropping years increasing, phosphatase activity in soil of tomato increased, catalase, sucrase, urease activity decreased, numbers of soil bacteria and actinomycete decreased, numbers of soil fungi increased.Maize, tomato, greengrocery and celery were planted before cropping cucumber. After cropping maize, greengrocery, celery and tomato, salinity content and electric conductivity in soil decreased 49.03% and 60%, 27.80% and 28.48%, 23.55% and 24.43%, and 16.99% and 16.33%. After cropping maize was the best effect in soil of decreasing salinity and electric conductivity. In development prophase, the cucumber which after cropping maize grown quickly, plant height increased 3.67-5.72%, 5.36-7.48%, 89.91 -87.47%than that after cropping greengrocery, celery and tomato, leaf numbers was more and leaf area was bigger than others. In late-fruit stage, cucumber after cropping maize grown slowly than after cropping greengrocery and celery. Fruit numbers of cucumber after cropping maize was 20.I/plant, yield was 3.35kg/plant, fruit setting rate was 80%. Cucumber after cropping tomato grown slowly, distance between leaf was shorter, leaf area was smaller, fruit numbers was 16.4/plant, yield was 2.35kg/plant, fruit setting rate was 57.5%. Content of Vc in fruit of cucumber after cropping celery was 2.72 mg/lOOg, greengrocery was 2.68 mg/lOOg, maize was 2.55 mg/lOOg, and tomato was 2.43 mg/lOOg. Dissolubility matter in fruit of cucumber after cropping greengrocery increased than celery, and celery increased than maize, and maize increased than tomato. Content of nitrate and nitrite in fruit of cucumber after cropping tomato increased than maize, and maize increased than greengrocery, and greengrocery increased than celery. Physiological disease of cucumber after cropping tomato increased than greengrocery, and greengrocery increased than celery, and celery increased than maize. Main disease of cucumber after cropping tomato increased than celery, and celery increased than greengrocery, and greengrocery increased than maize. Disease plant of cucumber after cropping maize was few. Four enzyme activities in soil of cucumber after cropping greengrocery and celery increased than tomato and maize. Enzyme activity in soil of cucumber after cropping maize decreased than tomato. Numbers of bacteria, fungi and actinomycete in soil increased but numbers of actinomycete of cropping tomato decreased. Bacteria and Actinomycete numbers in soil of cucumber after cropping greengrocery reducedthan tomato, and increased than celery and maize. Actinomycete numbers in soil of cucumber after cropping greengrocery enhanced than tomato, and reduced than celery and maize. Fungi numbers in soil was not rule. Number of bacteria, fungi and actinomycete in soil of cucumber after cropping celery were waved, and not rule.Maize, cucumber, spinach, celery and garlic were plant before cropping tomato could decreased content of salinity, N03--N and electric conductivity in soil. After cropping maize, salinity content in soil reduced 49%, N03--N reduced 20.98%, electric conductivity reduced 70.3%. After cropping spinach, salinity content in soil reduced 38.31%, NO3--N reduced 10.09%, electric conductivity reduced 54.76%. Effect of cucumber after cropping on soil of decreasing salinity, NO3--N and electric conductivity was the worst. Plant height of tomato after cropping was the shortest, leaf and bud numbers were fewer, yield was 1.34kg/plant, fruit numbers was 8.2, abnormality fruit rate was 15.87%, but early epidemic disease and leaf mold were 7.7% and 10.2% in tomato after cropping maize. Tomato after cropping spinach grown quickly, bud numbers was more, yield was 1.72 kg/plant, fruit number was 13.1, abnormality fruit rate was 9.47%, content of Vc and sugar in fruit were higher, and fruit quality was better. Enzyme activity in soil of tomato after cropping spinach was the highest, and maize was the lowest in all treatment. Enzyme activity in soil of tomato after cropping cucumber increased than maize, and reduced than garlic and celery. Bacteria and fungi numbers in soil of tomato after cropping garlic were the fewest in all treatment, and actinomycete number reduced than spinach and celery, and increased than cucumber and maize. Bacteria, fungi and actinomycete numbers in soil of tomato after cropping spinach and celery were more than others.