Effects Of Different Fertilization Methods On Soil Physical And Chemical Properties And Plant Growth In Pepper Orchard

Pepper is an important tropical commercial crop in China,but the traditional planting management technology based on manpower is still adopted,of which loose soil and fertilization are the main field management links,and labor input accounts for40% of the total input,which is the main manpower input links.In this experiment,the effects of five different loosen-fertilization methods: mechanical fenlong fertilization(fenlong integrated machine loosen-fertilization,depth of 40 cm,referred to as fenlong),machine-turning fertilization(excavator soil turning fertilization,depth of 40 cm,referred to as machine-turning),no-tillage(surface shallow compost,depth of 5 cm),artificial fertilization(artificial soil turning fertilization,depth of 40 cm,referred to as manpower)and artificial fertilization(artificial soil turning fertilization,depth of 40 cm,referred to as conventional planting)under conventional equal row spacing planting mode on soil physicochemical properties,plant nutrient absorption and utilization,photosynthetic characteristics and yield in pepper orchard were studied by combining field experiments with laboratory analysis.The main conclusions are as follows:(1)Effect of different fertilization methods on soil physical properties of pepper orchardDifferent fertilization methods had certain effects on soil physical properties,and fenlong fertilization method could reduce soil bulk density,increase soil porosity and soil water content,and facilitate the growth of pepper roots,which indicated that deep loosen-fertilization could reduce soil bulk density and improve soil water content and soil porosity.(2)Effect of different fertilization methods on soil chemical properties of pepper orchardDifferent fertilization methods had a significant effect on soil pH and nutrient content,and fenlong fertilization could better stabilize the pH of each soil layer and increase the soil pH above 40 cm soil layer;compared with no-tillage,it increased by5%～18.8%,which was not conducive to the growth of pepper roots.As the growth process of pepper advances,the nutrient content in the soil changes from high to low,and there is a tendency to migrate to the lower layer.Among them,powder ridges and soil turning and fertilization can increase the organic carbon content in the 20～80cm soil layer,compared with No-tillage increased by 12.6%～66.9%,powder ridge fertilization had a greater impact on the available nutrients in the 0～60cm soil layer.Compared with no-tillage,it increased the content of available nitrogen by 9%～68.3% and the available potassium by 2.3%～53.5%.Content and 3.1%～46.2% available phosphorus content.(3)Effect of different fertilization methods on nutrient absorption and utilization of plantsDifferent fertilization methods also had a significant effect on plant nutrient absorption and utilization,and at the main flowering stage of pepper,the leaf nitrogen and calcium contents were significantly higher under fenlong fertilization than under no-tillage,while other nutrient fenlong methods were increased to some extent,but there was no significant difference between the fertilization treatments.At the expansion stage,the phosphorus and calcium contents in the leaves were significantly higher under fenlong fertilization than under no-tillage,while other nutrients were also increased to different extents relative to other fertilization methods.At the grouting stage,the calcium and magnesium contents in the leaves were significantly higher under fenlong fertilization than no-tillage.At the maturity stage,the Ca contents in the leaves were significantly higher under fenlong fertilization than no-tillage,and the other nutrient contents were also increased to different extents,while the differences were not significant.(4)Effect of different fertilization methods on photosynthetic characteristics and yield of plantsThe study of pepper growth by different fertilization methods showed that the unit yield of soil turning fertilization was higher than that of no-tillage in each planting mode;the unit yield showed fenlong > machine-turning > conventional planting >manpower> no-tillage in each fertilization mode,and there was a significant difference in unit yield between fenlong and no-tillage mode;the seed yield under mechanical fertilization was significantly higher than that of no-tillage,but there was no significant difference between mechanical fertilization mode and manpower fertilization mode;the spike length under fenlong fertilization was significantly greater than that of no-tillage,but there was no significant difference between mechanical fertilization mode and other fertilization modes.Further studies revealed that the net photosynthetic rate under different fertilization methods at each growth stage also showed fenlong > turning > manpower > no-tillage,while there was no significant difference in intercellular carbon dioxide concentration and leaf temperature vapor pressure deficit between treatments;The regression coefficient of yield was positive,so the net photosynthetic rate at main flowering stage was the key factor affecting fenlong yield,which was also the main reason why the yield under fenlong was higher than that under each fertilization methods,indicating that the net photosynthetic rate at main flowering stage increased.