| For the serious phenomenon of facilities vegetable diseases in Ningxia, chosed the most common three kind of diseases (rotten flesh disease, fusarium wilt in tomato and cucumber root knot nematode disease) as the research object, investigated test greenhouse and analysised test soil sample,systematic exploration is soil nutrients, salt ions, heavy metals, trace elements, microbial and nematode community structure and diversity changes rotten flesh disease and fusarium wilt in tomato of different incidence rate and root knot nematode disease in cucumber under different cultivating years to measure the health of facilities soil in Ningxia. The results of the study are as follows:I. Comparative study on soil quality under different disease incidence rate of rotten flesh disease in tomato shows that:(1) Compared with the disease-free soil, incidence of soil nutrients were accumulated, available nitrogen, ammonium nitrogen is proportional to the degree of disease, the accumulation of available potassium available phosphorus and the soil organic matter were highest in the incidence of 15% of soil, and available potassium,available phosphorus and the soil organic matter were increased by 53%,393% and 77% compared with disease-free soil.(2) The salt ions are accumulated with the increase of incidence rate, and the content of the soil is the biggest in the most serious disease. The salt ions in soil of the incidence rate was 15%,20%,30% increased by 17%,10%,45% compared with disease-free soil.(3) Zinc, manganese, copper, iron, lead, chromium and cadmium were accumulated with a large amount of in incidence of 30% of soil. Cadmium content in the incidence rate of 20% and 30% of soil exceeds the national standard.(4) The number of bacteria and total number of bacteria in diseased soil was increased, and the number of bacteria was the highest in the incidence of 20% of soil. In contrast, fungi and actinomycetes decreased, with a maximum reduction in the incidence of 30% soil.(5) Microbial biomass carbon and nitrogen content was the highest in the incidence of 15% of soil, and increased by 278% and 426% compared with disease-free soil content.Ⅱ. Comparative study on soil quality under different disease incidence rate of fusarium wilt in tomato shows that:(1) Available nitrogen, phosphorus, potassium and ammonium nitrogen of diseased soil have increased compared with disease-free soil, Most available potassium and available phosphorus in the incidence of 30% of soil, Most available nitrogen and ammonium nitrogen in the incidence of 60% of soil, Most of the soil organic matter in the incidence of 20% of soil, and increased by 59% compared with disease-free soil,the least amount of organic matter in the incidence of 60% of soil,and decreased by 21% compared with disease-free soil.(2) With the increase of disease, Ca2+,Cl-,Na+,K+ and SO42- first increased and then decreased, HCO3- decreased, Mg2+ increased, the total amount of salt ions increased first and then decreased. Compared with disease-free soil, the total salt content in the incidence of 10% of soil increased by 3%, and the total salt content in the incidence 20%,30%,40%,60% decreased by 4%,2%,5%, and 14%, respectively.(3) Lead, manganese, zinc and iron accumulation in a large number of other incidence of soil in addition to the incidence of 10% of soil, and the highest accumulation in the incidence of 60% of soil, most copper and chromium in the incidence of 30% of soil.(4) The number of bacteria and the total bacteria in the soil increase obviously compared with disease-free soil, the number of fungi and actinomycetes decreases.(5) Microbial biomass carbon increased in 10%,20%,30% compared with disease-free soil, the largest increase in the incidence of 30%of soil, in addition to the incidence of 40% of soil, microbial biomass nitrogen were accumulated in other soil, Similarly, the largest increase in the incidence of 30% of soil.Ⅲ. Comparative study on soil quality root knot nematode in cucumber under different cultivating years shows that:(1) Available phosphorus is proportional to the cultivating years, With the increase of the cultivating time, the potassium content increased first and then decreased, The content of available nitrogen and ammonium nitrogen decreased in cultivating soil for many years, most of the soil organic matter in the 10 years of cultivating soil, increased by 50% compared with the soil organic matter in the 1 years of cultivating soil.(2) With increase of cultivating years,Ca2+, Mg2+, K+ and Na+ accumulated gradually, HCO3-, Cl-and SO42- of cultivating soil for many years less than planting for 1 years soil, soil salt ion increased by 16% planting for 16 years soil.(3) Enrich the content of iron and manganese in cultivating soil for many years, besides cadmium, other heavy metals are in the range of national grade 1 standard soil, the content of cadmium in planting for 1,8,10,13,16 years soil were 1.3 times,3.5 times,3.5 times,8.4 times,4.2 times of national grade 1 standard.(4)With the extension of cultivating years, bacteria and total bacteria count increases, the largest number in the planting for 16 years soil, fungi and actinomycetes first decreased and then increased, as the largest number in the 16 years of cultivating soil.(5) With the extension of cultivating years, the microbial biomass carbon and nitrogen content first increased and then decreased, the most soil microbial biomass carbon content in the planting for 10 years soil, and the most microbial biomass nitrogen in the planting for 8 years soil, after a little change.(6) 21 genera that are all advantages and common were identified. The total number of the nematodes and Plant-parasites decreased in the order of 10years>16 years> 13 years> 8 years> 1 years,the total number of the nematodes differeted cultivating years, ranged from 61 to 437 individuals per 100 grams of dry soil.(7) The nematode ecological indices responded differently to the cultivating years. The Shannon index (H’) decreased in the order of 16 years> 13 years> 1 years> 8 years> 10 years, the evenness index (J) decreased in the order of 13 years> 16 years> 1 years> 8 years> 10 years, and the dominance index (X) was in the order of 10 years> 16 years> 13 years> 8 years> 1 years. Nematode channel rati of differeted cultivating years ranged from 0.68 to 1.00.(8) Wasilewska index in the order of lyears> 8 years> 13 years> 16 years> 10 years; 1 year cultivating soil had the highest maturity index (MI),with the increase of cultting years, maturity index (MI) first increased and then decreased, there is the lowest MI value in 10 year cultivating soil, on the contrary, a maximum of parasite index(PPI) in 1 year cultivating soil, the minimum appeared in 10 years cultivating soil,with the increase of cultivating years, parasite index(PPI)first increased and then decreased,10 year cultivating soil had the highest PP I/MI also.(9) Richness index(SR) indices responded differently to the cultivating years,there are most abundant nematodes species in 8 year cultivating soil.(10)The result of nematode faunal analysis showed only soil sample that plantinglO years falled in the Ⅳ quadrant, the rest of soil sample were in I the quadrant. |
PDF Full Text Request