| The high temperature is the main obstacle factor for summer facility seedling,and the factory seedling needs fine environmental regulation.Under the direction of development to the nursery,using the advantage of high altitude climate cold summer cool to seedling nurturing seedlings can not only save energy,reduce the cost of seedling,can also improve the quality of seedlings,cultivating strong seedling,in line with the best geochemical cultural concept.To find out the mountains in the summer the effect of seedling,the article adopts the method of comparative study of,respectively,the mountains and plains in henan province is in the same time sow,standardized management of test,the detailed test the microclimate environment of the two regions and tomato seedlings growth and development of the situation.Respectively,the basic features of the mountains and plains in both temperature seedling growth indicators,the suitability of the quantitative evaluation,suitability of period of time,suitability,regulation time,suitability,and seedling growth index as well as the influence on systematic analysis of the relationship between temperature suitability quantitative evaluation model is set up,and thus to the limiting factors for precise control.The main conclusions are as follows:1.The analysis of the basic characteristics of the temperature in the mountains and plains in summer shows that the overall temperature characteristics of the mountain are better than those of the plain.Compared with the plains,the average daily temperature(25.45°C)of the mountains during the nursery period is 3.32°C lower than that of the plains(28.77°C),and the daytime average temperature of the mountains(28.16°C)is 1.87°C lower than that of the plains(30.13°C).(21.92°C)is 4.22°C lower than the plain(26.14°C).The temperature difference between day and night(7.43°C)is 3.39°C higher than that of the plain(4.04°C),and the difference is significant.During the nursery period,the daily average temperature of the substrate(24.84°C)was 1.58°C lower than that of the plain(26.42°C),and the daytime substrate temperature(28.78°C)in the mountain was 1.48°C lower than that of the plain(30.26°C),and the nighttime substrate temperature of the mountain(21.16 °C)is 7.58 °C lower than the plain(28.74 °C).The temperature difference between day and night(7.04 °C)is 5.15 °C higher than that of the plain(1.89 °C),and the difference reaches a significant level.During the seedling raising period,the total temperature higher than 33°C lasted 222 hours in the high mountains and 176 hours in the plains,and the high temperature of the high mountains was 26.14% higher than that of the plains.High temperatures typically appear between 10:00 and 15:00.Under typical weather conditions,sunny days in the mountains are higher than the plain during daytime and lower than the plains during the day;the temperature of the cloudy and rainy plains is higher than the plains during the day and at night,indicating that the temperature difference between day and night in the mountains is large,which is conducive to the accumulation of dry matter in tomato seedlings.2.From the results of vegetative growth indicators and physiological indicators of high mountain and plain tomato seedlings in summer,it can be seen that the plant height,stem diameter,dry fresh weight,root/shoot ratio,and strong seedlings of tomato seedlings were higher than the plains during the whole seedling cycle.Index soluble sugar content,root activity,and SPAD value were all significantly better than that of the plain,indicating that the summer mountain environment is more conducive to the growth of tomato seedlings.The seedling height,stem diameter,and dry weight of the whole plant at 28 days after sowing were 1.21,1.16,and 1.39 times that of the plain;the growth rate was 39.52% higher than the plain,and the strong seedling index was 1.34 times that of the plain.At 28 days after sowing,the content of soluble sugar in high mountains was 37.91% higher than plain.On the 28 th day after sowing,the roots of the lived mountain were 165.45% higher than the plains.At 28 days after sowing,the SPAD value of high mountains was 9.02% higher than the plains.From the above results,it was shown that the height of the mountain can be shortened compared with the plain,and the seedling soluble sugar content,root activity and chlorophyll SPAD value can be shortened,and the seedling quality can be improved.3.Establish a model to quantitatively evaluate the temperature characteristics of facilities,and explain the calculation methods for daytime,nighttime,and substrate temperature suitability.Combine the measured temperature data to calculate the suitability of the quantitative evaluation model and quantify the temperature suitability.The appraisal model calculated the suitability degree and obtained that the minimum value of the daytime suitability was 0 and the maximum value was 1;the minimum value was 0 at night,the peak value was 0.99,and the plain was 0.83;the minimum value of matrix suitability was 0,the maximum value.1;combining the minimum,maximum,and optimum temperature of the tomato seedlings and the division of the suitability of the forefathers to the scientifically divided suitability,set to two nodes 0.3 and 0.7,ie ? 0.7 is appropriate;[0.3,0.7)Suitable for sub-optimal;<0.3 is not suitable.The proportion of the suitability grades obtained by statistics shows that the proportion of “appropriate” grades in the mountains is greater than that of the plains,and the grades of “inappropriate” are all smaller than the plains.The total values of "suitable","sub-optimal" and "inappropriate" for the total temperature suitability of the mountains are 2.23,1.14 and 0.11 times that of the plains;the suitability of the typical weather is the "suitable" and "sub-optimal" values for the high mountains.The total value of "inappropriate" is 1.52,2.29,and 0.18 times the plain.According to the dynamic curve of suitability degree,it can be concluded that the summer season of high mountains and plains is 10:00-15:00 and the nighttime of the plain is the key regulation period.The sunny weather of typical weather is the key weather of temperature regulation.4.According to the correlation analysis of temperature suitability index on seedling index,it is concluded that the daytime temperature suitability has a greater influence on seedling seedling index,aboveground dry mass and underground dry mass,and has less influence on root-shoot ratio;It has a great influence on the root-shoot ratio of seedlings,and has little effect on strong seedling index,aboveground dry mass and underground dry mass;the temperature of the substrate has a greater influence on the above-ground dry weight of seedlings and the quality of underground dry mass.The root to crown ratio has less effect.5.In this paper,the consistency of the results of the model for temperature quantitative evaluation using temperature run characteristics is recalculated.Compared with plains,the high temperature during the whole nursery period when the daytime temperature is higher than 25°C is 2.87 hours lower than that of the plain,and the nighttime temperature is high.The high temperature at 17°C lasted 0.53 hours longer than the plain,and the high temperature with the substrate temperature higher than 22°C lasted 9.2 hours lower than the plain,and the high temperature lasted a total of 12.6 hours lower than the plain;the high temperature with the daytime temperature higher than 33°C lasted 0.9 hours lower than the plain.The high temperature at night when the temperature is higher than 25°C is 6.06 hours lower than the plain,and the high temperature when the substrate temperature is higher than 28°C is 3.56 hours lower than the plain,and the total temperature is 10.52 hours lower than the plain.The high temperature intensity and high temperature intensity of the mountain are lower than the plain during daytime,at night,and in the substrate.The temperature environment of the mountain effectively reduces the degree of high temperature experienced by the seedlings.6.Through the analysis of path analysis,the direct effect of temperature suitability on seedling index is day>night>matrix;root-to-crown ratio is night>day>matrix;dry matter,aboveground dry mass,and underground dry mass are both daytime>matrix.> At night. |
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