Development And Application Of Vegetable Functional Nursery Substrate Containing Arbuscular Mycorrhizal Fungi

With the rapid development of protected horticultural in recent years.Organic substrate,which is similar to soil cultivation,is the basis of soilless substrate culture.It can provide plenty water,gas and fertilizer rhizospheric environment and plays the role of support and fixation of plant as well as water nutrients and oxygen supply.Arbuscular Mycorrhizal Fungi(AMF),a microbe that can form mutual symbiosis with the roots of plants.AMF is widely distributed in farmland,forest,grassland,desert and other ecological system.AMF can effectively improve soil structure,help the plant absorption of mineral nutrition and moisture,promote plant growth,increase plant resistance and improve fruit quality,etc.AMF is widely applied in many fields and plays important roles in agroforestry production.Therefore,preserving the AMF in solid organic substrate and producing functional organic substrates that contain AMF can improve the effects of application of mycorrhizal biotechnology in horticulture and agroforestry,which helps make full use of the biodiversity of AMF and plays a significant role in the sustainable development of horticulture and agroforestry.We studied the effects of substrate that are mixed by peat,coconut chaff,vermiculite,perlite and other organic substrates in 18 ratios on the activity of AMF and screened suitable formula for the conservation AMF.We also studied the activity of AMF under different physical and chemical properties and screened the suitable condition for the proliferation and conservation of AMF.On the basis of the above mentioned work,we produced organic substrates that contain AMF to further study its efficiency of seedling on common vegetables,which will provide theoretical basis for the development of AMF containing substrates products in technical support.The main research results are as follows.1.Peat,coconut chaff,vermiculite,perlite and other organic substrates were mixed in different ratios and the difference of physical and chemical properties of AMF is significant.Too high or too low volume-weight and total porosity have negative effects on the activity of AMF.The activity of AMF is stable under the condition of volume-weight and total porosity with T18.Too high pH suppress the activity of AMF,which is the same with EC.lower N content will suppress the activity of AMF,so is too high N content.High P content will also has the same effect.And a high concentration of metal content is not suitable for the growth and activity of AMF.The results show that,the activity of AMF can keep high in the substrate with physical and chemical properties as follows,pH=5.62,EC=2.67 mS·cm-1,volume-weight=0.24 g·cm-3,and total porosity=54.37%.This can be a suitable physical and chemical property to preserve AMF.2.With peat,coconut chaff,vermiculite,perlite and other organic substrates that were mixed in different ratios being breeding substrates,Rapid-growing tomato being the host,we inoculated two different kinds of AMF,Glomus versiforme(GV)and Glomus mosseae(GM).Considering the change of organic matter,microbial respiration intensity and hydrolase activity of the substrates,peat:coconut chaff:vermiculite:perlite=2:2:1:1 is the best ratio to conserve AMF.And in the same time,the activity of Catalase,urease and alkaline phosphatase was significantly increased.Organic substrates are convenient to carry and it is easy to get the raw material and prepare.Furthermore,the conservation condition is easy to control,which is suitable for the large-scale preservation of AMF.3.With tomato being as host,we conserve AMF with plug breeding method and produce functional vegetables organic substrates containing AMF.First,conduct tomato breeding to multiply and activate AMF.30 days later,cut the acrial part,preserve root and gather the breeding substrate.Then apply the organic substrates with AMF in vegetables breeding and mix the breeding substrates with 4 fold mixed substrates(peat:coconut chaff:vermiculite:perlite=2:2:1:1).Finally,we achieve the breeding substrates with AMF.Comparing to the contrasts,substrates with AMF has an advantage in tomato,cucumber,pakchoi and lettuce.It promotes the growth of seedlings and increase the net photosynthetic rate in different degrees.