Effects Of Corn And Soybean Belt Compound Planting On Maize Growth And Development In Irrigation Area Of Ningxia

To clarify the impact of strip intercropping of corn and soybean on corn growth and development in the Ningxia irrigation area,four strip intercropping treatments were set up:2+3(M2:S3),2+4(M2:S4),4+3(M4:S3),and 4+4(M4:S4),along with sole-cropping of corn(M)and soybean(S)as controls.The corn variety tested was Xianyu 1225 and the soybean variety was Zhonghuang 30.Two planting densities were used:75,000 plants/ha and 82,500 plants/ha.By studying the population structure and characteristics,material production and distribution patterns,yield formation,and canopy light environment of corn under strip intercropping with soybean,the quantitative analysis of the effect of corn and soybean intercropping on corn growth and development in the Ningxia irrigation area was carried out.The results provide theoretical references for the application of corn and soybean strip intercropping in regional agriculture.The main findings are as follows:(1)Compared with sole-cropping of corn,strip intercropping reduced the yield by 25.1%to 41.4%,with M2:S4 showing the greatest reduction in yield at 41.4%and M4:S3 showing the smallest reduction at 25.1%.Compared with sole-cropping of corn,the components of corn yield were reduced,with harvested ear number reduced by 4.2%to 14.9%,1000-grain weight reduced by 0.5%to 3.6%,and single-ear grain number reduced by 5.2%to 10.8%.The effects of strip intercropping on the spike and plant traits of corn were investigated,and it was found that the length of the ear was reduced by 6.1%to 11.2%,and the stem diameter was reduced by 14.4%to 19.4%.Considering the comprehensive indicators of corn yield components and plant traits,strip intercropping with M2:S4 had a greater impact on corn,while M4:S3 had a smaller impact.(2)The single leaf area per plant at the jointing stage was decreased by 2%to 36.4%compared with sole-cropping,with M2:S3 showing the smallest reduction at 2%and M2:S4 showing the greatest reduction at 36.4%.During the silk period,the leaf area index increased by 7%to 11.4%compared with the control,with M4:S3 showing the greatest increase at 11.4%and M2:S4 showing a slight increase of 1.7%.The leaf area index showed a decrease of 2.7%to 42.7%during the jointing stage and an increase of 3.1%to 15.9%during the silk period compared with sole-cropping,with M4:S3 showing the smallest increase at 15.9%and M2:S4 showing the greatest decrease at 8.8%.Leaf length was most affected by M4:S4,with a reduction of 0.9%to 14.2%,while M2:S4 had the smallest effect,with a reduction of 0.2%to 15.7%.Leaf width was most affected by M4:S3,with a reduction of 0.(3)In the intercropping of maize with forage species,during the silk phase,there was a significant reduction in dry matter distribution compared to monoculture treatments,with a 16.6%～30%reduction.The M2:S3 treatment had the least impact,with an increase of 7.3%,while the M4:S4 treatment had the greatest impact,with a reduction of 30%.In terms of population biomass allocation,the matured corn dry matter distribution in intercrop treatments had the largest reduction compared to monoculture treatments,with a reduction of 0.5%～40.5%,and the M4:S3 treatment had the least impact,with a reduction of 0.5%,while the M2:S4 treatment had the greatest impact,with a reduction of 40.5%.The total dry matter weight at maturity stage showed a reduction of 4.3%～42.7%in intercropping treatments compared to monoculture treatments,with the M4:S3 treatment having the least impact,with a reduction of 4.3%,and the M2:S4 treatment having the greatest impact,with a reduction of 42.7%.(4)In intercropping treatments compared to monoculture treatments,there was an increase in photosynthetic potential of 3.1%～20.4%,with the M4:S3 treatment having the highest increase at 8.4%.The M2:S4 treatment had the greatest impact,with a reduction of 8.4%.Regarding light transmittance of the population,basal light transmittance had the most significant impact on corn during the milk stage,with the M2:S4 treatment having the least impact,with an increase of 72.8%,and the M4:S3 treatment having the highest impact,with an increase of 52.8%.At the tassel stage,the light transmittance of the ear had the most significant impact,with the M4:S3 treatment having the least impact,with a reduction of 50.9%,and the M2:S3 treatment having the highest impact,with a reduction of 67.6%.Intercropping maize in rows showed that the inter-row photosynthetic yield compared to monoculture decreased by 12%～39.6%in the east rows and decreased by 23.1%～44%in the west rows,with both treatments having the M4:S3 treatment having the least impact and the M2:S4 treatment having the greatest impact.(5)Under different planting densities,intercropping at a density of 7.5 plants per square meter had a reduced yield of 25.3%～43.8%and a decrease in the number of harvested ears of 6.5%～19.7%,a reduction in the thousand-grain weight of 0.5%～5%,and a decrease in the number of grains per ear of 3.6%～6%compared to monoculture at a density of 8.25 plants per square meter.(6)Among the total yield of mixed planting,the M4:S3 ratio had the least influence with a decrease of 20.3%,while the M2:S4 ratio had the greatest influence with a decrease of 33.7%.Among the overall benefits of mixed planting,the M4:S3 ratio had the least impact with a decrease of 16.2%,while the M2:S4 ratio had the greatest impact with a decrease of 27.7%.Through the data analysis of plant traits,material production,dry matter accumulation and distribution,light environment,and output benefits under the strip mixed planting mode,combined with the output benefits,it was concluded that the M4:S3 model had the least overall impact on corn growth,with the lowest yield and benefit reduction.The M4:S3 model was preliminarily selected as the promotional model for strip mixed planting in the Ningxia irrigation area.