Study On Chemical Seedling Raising Technology And Popularization Strategy Of Straw Based Materials

Rice is the largest grain crop in China.Machine transplanting technology is conducive to large-scale rice planting,which is consistent with China’s current agricultural production needs.Cultivating strong seedlings is the basic premise of machine transplanting.The traditional seedling raising methods include nourishing soil and commercial substrate.However,in recent years,large-scale seedling raising has encountered problems such as time-consuming and difficult soil borrowing.The consumption of soil resources in seedling raising production has been increasing,resulting in the destruction of arable soil,The problems of seedling diseases in the process of seedling raising are becoming more and more serious.There are some shortcomings in substrate seedling raising,such as low seedling quality,insufficient fertility in the later stage,poor seedling packing,and small seedling age elasticity,which affect the further promotion of rice seedling substrate.With the progress of science and technology and production methods,the total amount of crops in China has been rising.The total amount of straw has reached 1 billion tons.Straw returning to the field accounts for 60%of the comprehensive utilization of straw.However,straw returning to the field will affect the emergence rate of crops and the survival rate of transplanted seedlings.Long term straw returning to the field also brings problems such as damage to soil structure,diseases and pests.The results show that straw is rich in nutrient elements and organic matter,which can provide a suitable growth environment for plant growth.Therefore,this paper uses crop straw to carry out the research and development of base material seedling raising technology,in order to conform to the development trend of machine transplanting,develop a seedling raising substrate that can cultivate machine transplanting strong seedlings,investigate the adoption willingness of straw base material seedling raising technology,and analyze the influencing factors of farmers’ adoption willingness of base material seedling raising technology by using structural equation model,in order to provide reference for the formulation of the technology promotion policy.The main results are as follows:1.The conductivity of St（straw base material）is 2.42 ms/cm,and the pH value is weakly acidic.Treatment s50n50（50%straw base material+50%nutrient soil）increased plant height,leaf age,SPAD value and pseudostem diameter by 30.54%,15.93%,23.06%and 15.03%respectively compared with treatment CS（commercial substrate）.The trend of nitrogen and phosphorus content in seedling root was consistent with that in shoot.The root nitrogen content in NS（nutrient soil）treatment was 70.3%higher than that in CS treatment 22 days after sowing.There was no significant difference in potassium content among st,s50n50 and s75n25（75%straw base material+25%nutrient soil）22 days after sowing.At the transplanting stage,the root system of seedlings was directly related to the yield.The effective ear of s50n50 was 83300 higher than that of CS per hectare.The nitrogen and phosphorus in the substrate of seedling raising have an important impact on the growth and development of seedlings.Straw based materials can provide a better physical and chemical environment for rice growth.It is feasible to use straw based materials to raise seedlings,but attention should be paid to adding nutrients in actual use,and the proportion of each nutrient content should be paid to when adding nutrients.2.Experiments were carried out on the effects of different nutrient additions and proportions in straw based materials on seedling growth,in order to clarify the amount and proportions of nutrients that should be added in straw based materials.The results showed that different fertilization rates had an important impact on the quality of seedlings,thus affecting the yield of seedlings after transplanting.The total length,surface area,average root diameter and root volume of appropriate fertilization treatment were 13.18%,6.68%,25%and 9.8%higher than those of no fertilization treatment.The activities of GS,GOGAT,GPT and got in the underground of seedlings increased first and then decreased with the increase of fertilizer application.The actual yield of appropriate fertilization treatment was the highest,which was 15.77%higher than that of no fertilization treatment.When the amount of fertilizer is too large,it is not conducive to the nutrient absorption of seedlings.When the amount of fertilizer is less or no fertilizer is applied,seedlings will lack nutrients.When nitrogen was 1.95g/plate,phosphorus was 1.05g/plate,and potassium was 0.75g/plate,the root packing strength of seedlings was appropriate,and the enzyme activity of seedlings could maintain a high level,which was conducive to the nutrient absorption of shoot and root system of seedlings,and improved the nutrient utilization rate,so as to facilitate the formation of machine transplanted strong seedlings.3.Based on the experiments in the first two chapters,experiments were carried out on the adaptability of straw based seedling raising,in order to verify the seedling raising effect of straw based seedling raising technology under the most commonly used sprinkler irrigation and flood irrigation.The results showed that the quality and nutrient content of seedlings treated with clay under sprinkler irrigation and flood irrigation were higher,the quality and nutrient content of seedlings treated with straw base material were similar to those treated with clay,and the seedling raising effect of straw base material under sprinkler irrigation was slightly better than that under flood irrigation.In the transplanting period,the nitrogen,phosphorus and potassium contents of seedlings treated with straw base material under sprinkler irrigation were 9.17%,9.6%and 1.66%higher than that under flood irrigation,The straw based seedling raising technology can adapt to the current mainstream irrigation mode of seedling raising,and has the application prospect of industrialized seedling raising.4.Taking Huai’an City and Yangzhou City in the north of the Yangtze River and Changzhou City and Suzhou City in the south of the Yangtze River in Jiangsu Province as sample areas,the influencing factors of farmers’ willingness to adopt straw based seedling raising technology were studied.The results of Changzhou and Suzhou samples show that the path coefficients of effect display,perceived usefulness,external influence and perceived ease of use on Farmers’ willingness to adopt straw based seedling raising technology are 0.202**（0.001