| Wheat is an important food crop in Henan,and the increase in yield has always been the focus of research by agricultural scientists.The previous generation increased the seeding rate by using equal spacing,and found that the density was too large and resulted in problems such as poor ventilation and light transmission,thin and weak plants,and reduced yield.The use of wide and narrow rows of sowing,wide spacing of wheat to improve ventilation and light transmission capacity,is conducive to the wheat to play a marginal advantage,but unreasonable spacing in the wide and narrow row spacing will cause corn to sow in wheat bran.In the winter wheat-summer corn integrated planting system,three row spacing levels of 20 cm-20 cm(R0),12 cm-12 cm-12 cm-24 cm(R1),and 13 cm-20 cm(R2)and three kinds of suitable density levels of 120 kg·hm-2(D1),157.5 kg·hm-2(D2),and 195 kg·hm-2(D3)in total 9 treatment combinations for wheat canopy structure,differences in microenvironment,photosynthetic characteristics,and yield were studied in the wheat season.Its main research results are as follows:Population allocation has a certain regulatory effect on wheat canopy structure.Compared with the treatment of different row spacing,winter wheat leaf area index(LAI)R0>R1>R2,after booting stage,R1>R2>R0;The total change trend of leaf inclination angle(MTA).was R1>R2>R0.There was a significant difference between R1 and R0 and R2 at 10 d and 20 d after anthesis,but the difference of row spacing between R0 and R2 was small.From the booting stage to the flowering stage,the canopy openness(DIFN)was R0>R1>R2,while the row spacing R1 was lower than R2 at 10-30 d after flowering.The different compositional factors of the canopy structure have different responses to the density.Before flowering,LAI and MTA increased with the increase of density(except for wintering R1D2),and there was a significant difference between D1 and D3.After anthesis,D2>D3>D1;the overall difference among the three densities was significant.DIFN had a density treatment of D1> D2> D3 20 days after anthesis and D1> D3> D2 at 30 days after anthesis.The SPAD,photosynthetic characteristics and light energy utilization efficiency of wheat were different in different population configurations.Spading SPAD values from booting stage to flowering stage showed R0>R2>R1.The SPAD value of row spacing after flowering stage was the largest,and was significantly higher than row spacing R0.The difference between R1 and R2 was smaller.The photosynthesis rate(Pn)and stomata conductance(Gs)of wheat after different row spacing showed a row spacing R1 higher than R0 and R2;The Radiation use efficiency(RUE)of grain and wheat after booting stage showed R1> R2> R0,and there were significant differences among the three types of row spacing.The SPAD values from the booting stage to the flowering stage under the same row spacing were D1>D2>D3.There was a significant difference between D1 and D3 treatments.The total trend of D2>D3>D1 appeared at 10 d after flowering,and the three densities were between 20 and 30.d significant difference;The Pn,Gs,transpiration rate(Tr)and intercellular CO2 concentration(Ci)in the population showed that the Pn,Gs,Tr decreased with the increase of the density before flowering,and the Pn,Gs,D2 wheat after 10 days after flowering.Ci,Tr maximum;From the wintering period to the booting stage,RUE showed significant differences between D3>D2>D1,D1 and D3 treatments,but little difference with D2,flowering period and grain population density D2>D3>D1,D1,D2 were significantly different.In the lower,middle,and upper layers,the relative light intensity gradually increases with the increase of height,and the three types of line spacing processing gradually increase with the increase of row spacing.R1 has the largest width and the R0 distribution is relatively uniform.The lower R1 has the narrowest humidity,and the average of different row spacings is R1>R2>R0.The CO2 concentration is consistent with the average relative humidity under different row spacing,but the concentration of R0 CO2 is higher than that of R2.The temperature of the wide and narrow rows in the middle layer R1 is lower than that of the R2 wide and narrow row,but both are smaller than R0;the narrow relative humidity R1,narrower than R2,the average row spacing humidity R1>R2>R0;R2 wide,narrow row CO2 The difference in concentration is small,and the width of R1 is greater than the narrow row,and the overall appearance is R0>R1>R2;The maximum wind speed increases as the row spacing increases,but it does not change much.The difference between the upper relative humidity is small,and the row spacing R1>R2>R0;the row temperatures of R1 and R2 are all higher than R0,but the average temperature of the narrow rows is low,and the final performance is R0>R2>R1;The wide-spaced wind speed is higher than the narrow line spacing,but the maximum wind speed of the row spacing such as R0 20 cm is higher than the total wind speed of 20 cm in the row spacing of R2.The temperature,CO2 concentration and wind speed at different heights decrease or decrease with the increase of density,and the relative humidity gradually increases with the increase of density.The number of grains per ear of three rows showed R0>R2>R1.Panicle number,grain weight and yield per hectare showed R1>R2>R0.Panicle number and yield between R0 and R1 were significantly different.The number of panicles under a certain row spacing showed D3> D2> D1,D1,D3 were significantly different,the number of grains per spike was D1> D2> D3,and D2 was the highest in grain weight at the different densities,followed by D3,D1 was smallest,and the yield was D2>D3> D1,and it shows a significant difference between the yields of D1 and D2 and a small difference from D3.According to the results of this study,from the perspective of improving the canopy structure,microenvironment and photosynthetic characteristics of the plant population,the combination of 12 cm-12 cm-12 cm-24 cm spacing and 157.5 kg per hectare sowing has not only the ability to make the structure improving,but also is beneficial to the ventilation and light transmission of the population.The plants are slow to grow old,and they have sufficient grains and feet,high yields. |
PDF Full Text Request