本文選題：氮肥 + 磷肥�。� 參考：《沈陽(yáng)農(nóng)業(yè)大學(xué)》2017年碩士論文

【摘要】：過(guò)量施肥可導(dǎo)致土壤酸化、鹽堿化的現(xiàn)象。特別是在設(shè)施生產(chǎn)中,長(zhǎng)期大量施用化肥導(dǎo)致土壤中氮磷鉀養(yǎng)分嚴(yán)重富積、土壤酸化、次生鹽漬化。隨種植年限的延長(zhǎng)土傳病害也越來(lái)越普遍,嚴(yán)重制約蔬菜生產(chǎn)的產(chǎn)量和品質(zhì)。這些已經(jīng)受到人們的廣泛的關(guān)注,但是目前關(guān)于土壤的養(yǎng)分失衡、酸化、次生鹽漬化對(duì)微生物群落結(jié)構(gòu)的平衡及土傳病害的的影響尚不十分清楚。本文采用室內(nèi)模擬培養(yǎng)試驗(yàn),排除作物的影響,研究土壤氮磷鉀積累、酸化及次生鹽漬化對(duì)土壤可培養(yǎng)微生物生長(zhǎng)繁殖、群落結(jié)構(gòu)平衡及土傳病原菌的直接影響,研究結(jié)果可為合理施肥、預(yù)防土壤土傳病害的發(fā)生提供理論依據(jù)。試驗(yàn)結(jié)果如下:(1)氮肥對(duì)土壤細(xì)菌、真菌和放線菌數(shù)量的影響都較為顯著,其中施用高氮量對(duì)放線菌生長(zhǎng)的抑制作用最大,其次是細(xì)菌。當(dāng)施氮量大于N2處理時(shí),放線菌生長(zhǎng)就會(huì)受到抑制;在高施氮量下土壤可培養(yǎng)枯萎菌生長(zhǎng)旺盛,數(shù)量快速增加。施氮肥改變土壤的微生物群落結(jié)構(gòu),當(dāng)施氮量大于N2處理時(shí),土壤中放線菌比例不斷下降,枯萎菌所占比例快速上升,逐漸成為優(yōu)勢(shì)菌群。(2)土壤鹽分和NH4+—N含量對(duì)土壤可培養(yǎng)細(xì)菌數(shù)量有直接的正影響,NO3-—N含量通過(guò)對(duì)鹽分的影響對(duì)可培養(yǎng)細(xì)菌數(shù)量有間接的影響。電導(dǎo)率和NH4+—N含量對(duì)土壤可培養(yǎng)真菌數(shù)量產(chǎn)生直接正影響,影響大小:電導(dǎo)率NH4+—N含量。水溶性鹽分含量對(duì)土壤可培養(yǎng)枯萎菌數(shù)量有較好的正直接影響,NO3-—N通過(guò)對(duì)水溶性鹽分含量對(duì)土壤可培養(yǎng)枯萎菌數(shù)量產(chǎn)生間接影響。(3)磷肥施入后,對(duì)土壤可培養(yǎng)細(xì)菌、真菌和放線菌有相同的變化趨勢(shì),當(dāng)施磷量大于P3處理時(shí)時(shí),土壤中的細(xì)菌、真菌和放線菌數(shù)量的生長(zhǎng)會(huì)受到抑制,但是致病真菌—枯萎菌數(shù)量依舊持續(xù)增加。施磷肥改變土壤微生物群落結(jié)構(gòu)變化,當(dāng)施磷量由P3增加到P4時(shí),土壤放線菌比例快速降低,枯萎菌比例快速上升。(4)鉀肥和磷肥對(duì)是土壤可培養(yǎng)微生物數(shù)量的影響是一致的,但是鉀肥對(duì)其影響小于磷肥;隨著施鉀量的增加,土壤放線菌比例和枯萎菌比例并沒(méi)有太大改變。(5)鉀肥施入后,土壤可培養(yǎng)微生物與土壤pH呈顯著負(fù)相關(guān),與水溶性鹽分含量呈顯著負(fù)相關(guān)。土壤可培養(yǎng)細(xì)菌數(shù)量受電導(dǎo)率直接影響大于pH。土壤水溶性鹽分含量和pH對(duì)土壤可培養(yǎng)真菌數(shù)量產(chǎn)生直接影響。水溶性鹽分含量對(duì)土壤可培養(yǎng)放線菌數(shù)量直接影響。水溶性鹽分含量和pH對(duì)土壤可培養(yǎng)枯萎菌產(chǎn)生直接影響。(6)氮磷鉀配施對(duì)土壤可培養(yǎng)真菌,尤其是致病真菌—枯萎菌數(shù)量影響最大,其次是放線菌,對(duì)細(xì)菌數(shù)量影響最小。速效磷含量含量對(duì)土壤可培養(yǎng)細(xì)菌和放線菌數(shù)量都有較好的正直接影響,NH4+—N含量對(duì)其產(chǎn)生較好的負(fù)直接影響;速效磷含量對(duì)土壤可培養(yǎng)真菌數(shù)量有較好正直接影響,pH對(duì)其產(chǎn)生較好的負(fù)直接影響;NH4+—N和NO3-—N含量通過(guò)對(duì)pH的影響對(duì)其數(shù)量產(chǎn)生間接影響;電導(dǎo)率對(duì)土壤可培養(yǎng)枯萎菌數(shù)量產(chǎn)生較好的直接影響;而NO3-—N含量通過(guò)對(duì)電導(dǎo)率的影響對(duì)其數(shù)量產(chǎn)生較好的間接影響。
[Abstract]:Excessive fertilization can lead to the acidification and salinization of soil, especially in the production of facilities. Long term application of chemical fertilizer leads to the serious accumulation of nitrogen, phosphorus and potassium in the soil, soil acidification and secondary salinization. The soil borne diseases are becoming more and more common with the prolongation of planting years, which seriously restrict the yield and quality of vegetable production. These have been affected by people. However, the effects of soil nutrient imbalance, acidification and secondary salinization on the balance of microbial community structure and soil borne diseases are not very clear. In this paper, indoor simulated culture tests were used to eliminate the effects of crops and to study soil nitrogen, phosphorus and potassium accumulation, acidification and secondary salinization. Growth and reproduction, community structure balance and the direct effect of soil borne pathogens, the results can provide a theoretical basis for rational fertilization and prevention of soil soil borne diseases. The results are as follows: (1) the effects of nitrogen fertilizer on the number of soil bacteria, fungi and actinomycetes are more significant, and high nitrogen application has the most inhibitory effect on the growth of actinomycetes. The growth of actinomycetes will be inhibited when the amount of nitrogen is greater than N2 treatment. The growth of the actinomycetes will be inhibited when the amount of nitrogen is high. The soil can grow rapidly and the number of the bacteria can be rapidly increased. The application of nitrogen fertilizer to change the microbial community structure of the soil, when the nitrogen application is greater than the N2 treatment, the proportion of actinomycetes in the soil is decreasing and the proportion of the Fusarium wilt is fast. Rising and gradually becoming dominant bacteria groups. (2) soil salinity and NH4+ - N content have a direct positive effect on the number of cultivated soil bacteria. The content of NO3- - N has an indirect effect on the number of cultured bacteria. Electrical conductivity and NH4+ - N content have direct positive effects on the number of cultivated fungi in soil: electrical conductivity NH 4+ - N content. Water soluble salt content has a good direct effect on the number of cultivated wilt in soil. NO3- - N has an indirect effect on the number of cultivated Fusarium Wilt in soil by water soluble salt content. (3) after the application of phosphate fertilizer, the soil culture bacteria, fungi and actinomycetes have the same trend of change, when the amount of phosphorus is greater than the P3 treatment At present, the growth of bacteria, fungi and actinomycetes in the soil will be inhibited, but the number of pathogenic fungi and Fusarium wilt still continues to increase. Application of phosphate fertilizer changes soil microbial community structure, when the amount of phosphorus is increased from P3 to P4, the proportion of soil actinomycetes rapidly decreases, and the proportion of Fusarium wilt rapidly increases. (4) potassium and phosphate fertilizer are the same. The influence of soil cultivable microbes was consistent, but the effect of potash fertilizer was less than that of phosphate fertilizer. With the increase of potassium application, the proportion of Soil Actinomycetes and the proportion of Fusarium wilt did not change much. (5) after the application of potassium fertilizer, the soil cultivable microorganism was negatively correlated with soil pH, and was negatively correlated with the water soluble salt content. The number of cultivated bacteria was directly affected by the electrical conductivity of the soil and the water soluble salt content of pH. soil and the amount of pH had a direct effect on the number of cultivated fungi in the soil. Water soluble salt content had a direct effect on the number of cultivated actinomycetes in the soil. Water soluble salt content and pH had a direct effect on the cultivated wilt of soil. (6) the application of N, P, K and K to soil The number of cultivated fungi, especially the pathogenic fungi - Fusarium wilt, was the most affected, followed by the actinomycetes, which had the least influence on the number of bacteria. The content of available phosphorus had a good direct effect on the number of cultivated bacteria and actinomycetes in the soil, and the content of NH4+ - N had a good negative effect on it; the content of available phosphorus could be cultivated in the soil. The number of bacteria has a good direct effect, and pH has a better negative effect on it. The content of NH4+ N and NO3- N has an indirect effect on the quantity of pH, and the conductivity has a good direct effect on the number of cultivated wilt of soil, and the content of NO3- N has a better indirect shadow by the effect on the electrical conductivity. Ringing.
【學(xué)位授予單位】：沈陽(yáng)農(nóng)業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：S154.3
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本文編號(hào)：1944536