Effects of nitrogen and phosphorus application on needle morphological and anatomical structure in Chinese pine seedlings
Nitrogen and phosphorus are the major nutrients that affect vegetation growth and productivity,and their rational application can promote the growth of Chinese pine seedlings;however,their effects on the needle morphology and anatomical structure are unclear.The effects of nitrogen and phosphorus application on the morphological and anatomical traits of currentyear needles in Chinese pine seedlings were studied through four treatments with seven applications per treatment:CK (no fertilizer use),N application (+ N,20 kg/hm2 per application),P application (+ P,10 kg/hm2 per application),and both N and P application (+ NP,20 kg/hm2 N + 10 kg/hm2 P per application).The results showed that the application of nitrogen,phosphorus,or nitrogen and phosphorus increased the stem diameter,crown size,and aboveground biomass.Nitrogen or phosphorus application increased current-year needle nitrogen or phosphorus content significantly.Nitrogen application had little effect on the length,width,thickness,and surface area of the current-year needles;however,phosphorus application increased the needle length,width,thickness,and surface area.Nitrogen application significantly increased the area and the proportion of the central cylinder as well as the transfusion tissue of current-year needles,whereas phosphorus significantly increased the surface area of the epidermis,resin duct cavities,central cylinder,transfusion tissue,xylem,and phloem,and proportion of the resin duct cavities;the central cylinder and transfusion tissue also increased significantly.Nitrogen application affected 4 of 22 morphological and anatomical structure parameters,whereas phosphorus application had an obvious influence on 14 of 21 parameters,indicating that phosphorus application had a stronger effect on the needle morphology and anatomical structure than nitrogen application.Principal components analysis showed that phosphorus application mainly stimulated photosynthesis and resin production,and nitrogen or phosphorus application increased the function of the transfusion tissue.These results suggest that phosphorus is the major limiting factor for the growth of Chinese pine seedlings,and that phosphorus application should be highlighted in practice.
Chinses pine seedlingcurrent-year needlesmorphologyanatomical structurenitrogen and phosphorus application
NETL
NSTL
万方数据
维普
