LU500242B1 - An Arbuscular Mycorrhizal Fungi (AMF) Soil Conditioner and its Application in Soil Amelioration - Google Patents

Abstract

The present invention discloses an arbuscular mycorrhizal fungi (AMF) soil conditioner and its application in soil amelioration, belonging to the technical field of agricultural and forestry production. The soil conditioner contains the following raw materials according to the part by weight: 40-50 parts of livestock dung, 20-30 parts of peat, and 8-12 parts of AMF agent. The soil conditioner disclosed by the present invention can significantly increase AMF colonization rate of poplar fine roots, promote the symbiotic relationship between arbuscular mycorrhiza and root system, and improve the soil structure and the absorption of soil nutrients.

Description

DESCRIPTION An Arbuscular Mycorrhizal Fungi (AMF) Soil Conditioner and its Application in Soil Amelioration

TECHNICAL FIELD The present invention refers to the technical field of agricultural and forestry production, in particular to an arbuscular mycorrhizal fungi (AMF) soil conditioner and its application in soil amelioration.

BACKGROUND Dongtai Forestry Farm is a key shelterbelt forest in coastal area of Jiangsu Province, covering an area of 30,000 mu, and is one of the important nurseries bases for forestry. Although after 30 years of hard work, Dongtai Forestry Farm has changed its former appearance of wasteland and provided all kinds of trees and seedlings to all parts of the country, this area is still a saline-alkali land. In addition, the planting pattern is the same all year round, and forest management is carried out by using various chemicals, fertilizers, etc., so that the soil structure is destroyed, and the development of agriculture and forestry in China is seriously affected. At present, some soil conditioners have been developed for saline-alkali soil amelioration, but the existing soil conditioners only take into account the change of unilateral factors of soil composition, and do not specifically target the restriction and/or association between forest and soil, which leads to poor amelioration effect of the existing soil conditioners. In addition, existing soil conditioners are mainly made of existing chemicals, which are of high cost and limited source. Therefore, it is urgent to provide a soil conditioner with low cost, wide source and good performance to solve the defects of existing soil conditioners.

SUMMARY The purpose of the present invention is to provide an arbuscular mycorrhizal fungi (AMF) soil conditioner and its application in soil amelioration. The soil conditioner can significantly increase AMF colonization rate in tree roots, promote the symbiotic relationship between arbuscular mycorrhiza and root system, improve the soil structure, and promote the absorption of soil nutrients by trees.

For realizing the above-mentioned purpose, the present invention provides the following technical solution: The present invention provides an AMF soil conditioner, containing the following raw materials according to the part by weight: 40-50 parts of livestock dung, 20-30 parts of peat, and 8-12 parts of AMF agent.

Preferably, the livestock dung is a biological fertilizer obtained by fermentation of cow dung and sheep dung.

Preferably, the AMF strain is Glomus intraradices.

Preferably, the AMF agent is rhizosphere soil containing fungal spores, hyphae and infected root segments of the host plant, which is formed by propagating the AMF strain through the host plant.

Preferably, the AMF is inoculated with 3.5-7.5 % of the weight of the propagating substrate during maize propagation.

Preferably, the propagating substrate is a mixture of peat and sand at a weight ratio of

0.5-2:1.

The present invention also provides an application of the AMF soil conditioner in soil amelioration.

The present invention discloses the following technical effects:

1. As for the AMF soil conditioner provided by the present invention, the added AMF can promote the formation and stability of soil aggregates through entangling of hyphae and soil particles, secreting glomalin-related soil protein (GRSP), increasing soil organic carbon retention and other ways, so as to improve soil structure. Meanwhile, the addition of livestock dung and peat is beneficial to the propagation of AMF and the improvement of soil pH, organic carbon, nitrogen and phosphorus and other available nutrients, so as to realize the soil amelioration.

2. The raw materials of the soil conditioner provided by the present invention are from animal dung and peat, the source is very wide, the waste utilization is realized, and it is conducive to environmental protection. Furthermore, with low cost, the soil conditioner is convenient for popularization and utilization.

DESCRIPTION OF THE INVENTION The technical solution of the present invention is described in the form of embodiments, but it shall not be regarded as a limitation of the present invention, but shall be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention.

Unless otherwise specified, the test methods used in the following embodiments are conventional, and the materials, reagents, etc. used shall be commercially available.

The peat used in the following embodiments is commercially available. The stock seed of Glomus intraradices is provided by the Institute of Beijing Academy of Agriculture and Forestry Sciences.

Embodiment 1 The AMF soil conditioner contains the following raw materials according to the part by weight: 40 parts of livestock dung, 20 parts of peat, and 8 parts of AMF agent.

Livestock dung is a biological fertilizer obtained by fermentation according to the weight (wet weight) ratio (1:1) of cow dung and sheep dung. The conventional fermentation method is adopted: 0.5 kg organic fertilizer inoculant (purchased from Shandong Jianyuan Biotechology Co., Ltd.) is mixed with every 3 tons of processed raw feces. The fermentation is carried out in strips and piles. When the fermentation temperature reaches 45 °C, it needs to tip over evenly till the temperature reaches 55 °C. When the temperature reaches 60 °C, it is left standing for two days, and then it continues to tip over. The biological fertilizer is obtained when the temperature drops to normal temperature.

The AMF agent is prepared as follows: Glomus intraradices is inoculated on sterile propagating substrate (a mixture of peat and sandy soil at a weight ratio of 0.5:1) with 3.5 % of the weight of the propagating substrate; sterile maize seedlings are planted, and after 10 days of inoculation, water is irrigated every 5 days; after 45 days of culture, the rhizosphere soil of maize is collected to obtain the AMF agent.

Embodiment 2 The AMF soil conditioner contains the following raw materials according to the part by weight: 45 parts of livestock dung, 25 parts of peat, and 10 parts of AMF agent.

Livestock dung is a biological fertilizer obtained by fermentation according to the weight (wet weight) ratio (1:1) of cow dung and sheep dung. The conventional fermentation method is adopted: 0.5 kg organic fertilizer inoculant (purchased from Shandong Jianyuan Biotechology Co., Ltd.) is mixed with every 3 tons of processed raw feces. The fermentation is carried out in strips and piles. When the fermentation temperature reaches 45 °C, it needs to tip over evenly till the temperature reaches 55 °C. When the temperature reaches 60 °C, it is left standing for two days, and then it continues to tip over. The biological fertilizer is obtained when the temperature drops to normal temperature.

The AMF agent is prepared as follows: Glomus intraradices is inoculated on sterile propagating substrate (a mixture of peat and sandy soil at a weight ratio of 1:1) with 5 % of the weight of the propagating substrate; sterile maize seedlings are planted, and after 10 days of inoculation, water is irrigated every 5 days; after 45 days of culture, the rhizosphere soil of maize 1s collected to obtain the AMF agent.

Embodiment 3 The AMF soil conditioner contains the following raw materials according to the part by weight: 50 parts of livestock dung, 30 parts of peat, and 12 parts of AMF agent.

Livestock dung is a biological fertilizer obtained by fermentation according to the weight (wet weight) ratio (1:1) of cow dung and sheep dung. The conventional fermentation method is adopted: 0.5 kg organic fertilizer inoculant (purchased from Shandong Jianyuan Biotechology Co., Ltd.) is mixed with every 3 tons of processed raw feces. The fermentation is carried out in strips and piles. When the fermentation temperature reaches 45 °C, it needs to tip over evenly till the temperature reaches 55 °C. When the temperature reaches 60 °C, it is left standing for two days, and then it continues to tip over. The biological fertilizer is obtained when the temperature drops to normal temperature.

The AMF agent is prepared as follows: Glomus intraradices is inoculated on sterile propagating substrate (a mixture of peat and sandy soil at a weight ratio of 2:1) with 7.5 % of the weight of the propagating substrate; sterile maize seedlings are planted, and after 10 days of inoculation, water is irrigated every 5 days; after 45 days of culture, the rhizosphere soil of maize is collected to obtain the AMF agent.

Reference 1 Reference 1-1: the difference with Embodiment 1 is that the soil conditioner does not contain livestock dung and peat, and everything else 1s the same.

Reference 1-2: the difference with Embodiment 2 is that the soil conditioner does not contain livestock dung and peat, and everything else is the same.

Reference 1-3: the difference with Embodiment 3 is that the soil conditioner does not contain livestock dung and peat, and everything else is the same.

Reference 2 Reference 2-1: the difference with Embodiment 1 is that the soil conditioner does not contain peat and AMF agent, and everything else is the same.

Reference 2-2: the difference with Embodiment 2 is that the soil conditioner does not contain peat and AMF agent, and everything else is the same.

Reference 2-3: the difference with Embodiment 3 is that the soil conditioner does not contain peat and AMF agent, and everything else is the same.

Reference 3 Reference 3-1: the difference with Embodiment 1 is that the soil conditioner does not contain livestock dung and AMF agent, and everything else is the same.

Reference 3-2: the difference with Embodiment 2 is that the soil conditioner does not contain livestock dung and AMF agent, and everything else is the same.

Reference 3-3: the difference with Embodiment 3 is that the soil conditioner does not contain livestock dung and AMF agent, and everything else is the same.

Reference 4 Reference 4-1: the difference with Embodiment 1 is that the soil conditioner does not contain peat, and everything else is the same.

Reference 4-2: the difference with Embodiment 2 is that the soil conditioner does not contain peat, and everything else is the same.

Reference 4-3: the difference with Embodiment 3 is that the soil conditioner does not contain peat, and everything else is the same.

Reference 5 Reference 5-1: the difference with Embodiment 1 is that the soil conditioner does not contain livestock dung, and everything else is the same.

Reference 5-2: the difference with Embodiment 2 is that the soil conditioner does not contain livestock dung, and everything else is the same.

Reference 5-3: the difference with Embodiment 3 is that the soil conditioner does not contain livestock dung, and everything else is the same.

Reference 6 Reference 6-1: the difference with Embodiment 1 is that the soil conditioner does not contain AMF agent, and everything else is the same.

Reference 6-2: the difference with Embodiment 2 is that the soil conditioner does not contain AMF agent, and everything else is the same.

Reference 6-3: the difference with Embodiment 3 is that the soil conditioner does not contain AMF agent, and everything else is the same.

Cultivation experiments are carried out using the soil conditioners prepared in Embodiment 1-3 and References 1-6.

Sampled soil: the sampled soil were collected using a soil corer with an inner diameter of 4 cm to a depth of 20 cm from Dongtai Forestry Farm. The soil samples were pressed through

2.0 mm sieve for further analyses.

First, the sampled soil and the prepared soil conditioner mixed according to the weight ratio of 9:1 to obtain the cultivated soil. Using the round flowerpot as the culture container, 6 kg of cultivated soil was added to each flowerpot. At the same time, the experiment added the sampled soil only as the blank control. Each treatment was repeated 5 times, and a total of 110 flowerpots were used in this experiment. Then, the poplar seedlings were planted in flowerpots, and placed in a greenhouse at 25 °C, and carried out watering and routine management. We collected the fine roots of the poplar and the cultivated soil after three months cultivation.

The root segments of the poplar seedlings were stained by trypan blue. Root segments were selected randomly from the stained samples. 100 root segments per treatment were assessed for the presence or absence of AMF structures using a light microscope (Phillips, J.M. and Hayman, D.S. (1970), Improved procedures for clearing roots and staining parasitic and vesicular-arbuscular mycorrhizal fungi for rapid assessment of infection. Transactions of the British Mycological Society, 55, 158-161.). The AMF diversity of the cultivated soil is researched by ITS sequencing (Suzhou GENEWIZ Biotechnology Co., Ltd.), and the results are shown in Table 1.

Table 1 AMF diversity and colonization rate AMF Colonization Rate . . Shannon Diversity Species Richness (%) Index

Blank control 18.32 62.25 Reference 1-1 27.02 65.10 Reference 1-2 28.21 64.92 Reference 1-3 32.15 65.65 Reference 2-1 23.96 63.51 Reference 2-2 24.50 63.73 Reference 2-3 24.66 65.12 Reference 3-1 21.30 62.30 Reference 3-2 21.31 61.63 Reference 3-3 17.27 62.29 Reference 4-1 32.65 65.96 Reference 4-2 32.67 67.89 Reference 4-3 33.35 67.92 Reference 5-1 32.01 66.62 Reference 5-2 32.13 66.57 Reference 5-3 31.85 66.51 Reference 6-1 19.97 65.30 Reference 6-2 20.33 65.22 Reference 6-3 23.32 66.89 Embodiment 1 35.51 69.22 Embodiment 2 37.94 69.61 Embodiment 3 37.03 68.27 The cultivated soil of the above cultivation experiment is divided into two parts: one is air-dried for the determination of pH value, organic carbon, total nitrogen, total phosphorus and available phosphorus, and the other is stored at 4 °C for the determination of soil available nitrogen and water content.

The soil pH value is determined according to the pH of the forest soil (GB7859-87). The organic carbon and total nitrogen are measured using an elemental analyzer (Elementar Vario EL III, Elementar Analysen Systeme GmbH, Germany). Total phosphorus is determined by plasma emission spectrometer (ICP, PerkinElmer Optima 8000, USA). Soil available phosphorus were extracted using microwave digestion and a NaHCO; solution then measured using the Mo-Sb colorimetric method.

The available nitrogen is determined according to the method for determination of hydrolytic nitrogen in the forest soil (GB7849-87). The water content is determined according to the method for determination of forest soil moisture content (GB7833-87). The results are shown in Table 2.

Table 2 Soil chemical properties Organic Total Total Available | Available Carbon Nitrogen |Phosphorus| Nitrogen |Phosphorus (g/kg) (g/kg) (g/kg) (mg/kg) | (mg/kg) Blank control 11.62 | 142 | 069 | 12.69 Reference 1-1 12.56 12.72 Reference 1-2 12.55 12.75 Reference 1-3 12.56 12.81 Reference 2-1 13.20 15.31 Reference 2-2 13.21 15.35 Reference 2-3 13.23 15.32 Reference 3-1 11.69 13.34 Reference 3-2 11.69 13.31 Reference 3-3 11.71 13.34 Reference 4-1 13.25 15.56 Reference 4-2 13.29 15.69 Reference 4-3 13.40 15.66 Reference 5-1 12.54 13.35 Reference 5-2 12.55 13.36 Reference 5-3 12.59 13.31 Reference 6-1 13.41 15.04 Reference 6-2 13.49 15.21 Reference 6-3 13.54 15.24 Embodiment 1 13.28 | 1.8 | 090 | 15.30 Embodiment 2 13.65 15.59 Embodiment 3 14.22 15.51 The soil conditioner provided by the present invention significantly increased AMF colonization rate compared with the blank control (Table 1). Meanwhile, it also increased AMF species richness (Table 1). The soil conditioner provided by the present invention reduced the soil pH value and increased soil organic carbon, available nitrogen and available phosphorus content (Table 2). In addition, the soil conditioner provided by the present invention increased the AMF colonization rate than that in Reference and decreased the soil pH value than that in Reference, which indicated that the effect of AMF, livestock dung and peat added at the same time on soil amelioration was better, and the addition of AMF soil conditioner according to the ratio in Embodiment 2 has a better effect on soil improvement of the saline and alkali soil in Dongtai Forestry Farm.

In addition, the number of soil aggregates above 0.25 mm was significantly increased after sifting of the dry propagating substrate. The results showed that the entanglement of arbuscular mycorrhiza hyphae with poplar root system and the inclusion with soil particles could significantly increase the content of large aggregates and organic carbon.

In conclusion, the soil conditioner provided by the present invention has the potential to be applied to improve the soil in the salt-alkali land of Dongtai Forestry Farm, and can also significantly improve the structure of nutrients in the soil and the number of AMF, which is beneficial to the planting and growth of various trees in Dongtai Forestry Farm.

The above embodiments only describe the preferred mode of the present invention and do not limit the scope of the present invention. Without deviating from the design spirit of the present invention, all variations and improvements formed by ordinary technicians in this field to the technical solution of the present invention shall fall into the scope of protection specified in the Claims of the present invention.

Claims (7)

1. An arbuscular mycorrhizal fungi (AMF) soil conditioner, containing the following raw materials according to the part by weight: 40-50 parts of livestock dung, 20-30 parts of peat, and 8-12 parts of AMF agent.

2. The arbuscular mycorrhizal fungi (AMF) soil conditioner according to claim 1, wherein the livestock dung is a biological microbial fertilizer obtained by fermentation of cow dung and sheep dung.

3. The arbuscular mycorrhizal fungi (AMF) soil conditioner according to claim 1, wherein the AMF strain is Glomus intraradices.

4. The arbuscular mycorrhizal fungi (AMF) soil conditioner according to claim 1, wherein the AMF agent is rhizosphere soil containing fungal spores, hyphae and infected root segments of the host, which is formed by propagating the AMF strain through the host.

5. The arbuscular mycorrhizal fungi (AMF) soil conditioner according to claim 4, wherein the AMF agent is inoculated with 3.5-7.5 % of the weight of the propagating substrate during maize propagation.

6. The arbuscular mycorrhizal fungi (AMF) soil conditioner according to claim 5, wherein the propagating substrate is a mixture of peat and sand at a weight ratio of 0.5-2:1.

7. An application of the arbuscular mycorrhizal fungi (AMF) soil conditioner according to any one of claims 1-6 in soil amelioration.