Effects Of Water And Fertilizer Coupling On Seeding Growth And Physiology Of Camellia Nitidissima

The effects of different water and nitrogen treatments on the growth and physiological effects of the seedlings were studied by using the three-factor five-level quadratic regression combination design of Camellia nitidissima as the material.The relationship between water and fertilizer characteristics,leaf nutrient accumulation and demand regularity,and the correlation between the indicators of Camellia nitidissima.The optimum water and fertilizer level of Camellia nitidissima was screened out,and the utilization rate of water and fertilizer was improved,which provided the theoretical basis for the cultivation and popularization of Camellia nitidissima.The results are as follows:(1)The growth of plant height and ground diameter of Camellia nitidissima was the best in 10-12months,and the relative increment of plant height,relative diameter increase,ratio of leaf weight to root weight.In the main effect analysis,the three factors of water and phosphorus had a significant effect on the relative increment of plant height and diameter of Camellia nitidissima,and had no significant effect on biomass.In the coupling effect analysis,the interaction between water and nitrogen had significant effect on the relative increment of plant height.When the water and nitrogen were taken W=16%respectively,the relative increment of plant height was the highest when N=2.4g,And the relative increment of water diameter was the highest when W=16%and P=1.2g.The interaction between water nitrogen and water and phosphorus had a significant effect on biomass and when W=16%,N=3.6g,the Camellia nitidissima biomass appeared extreme.In addition to the root/shoot ratio,there was a significant positive correlation between the growth indexes,and the correlation between the leaf weight and the relative increase of the plant height was the largest.(2)There was no significant difference in the water content of Camellia nitidissima leaves,and there were significant differences in the photosynthesis indexes.In addition to Ci,the pn,Tr and Gs of Camellia nitidissima decreased with the increase of drought stress in the same amount of fertilizer.In the main effect analysis,the water content had a significant effect on the photosynthetic indexes pn,Tr,Ci and Gs of Camellia nitidissima.The nitrogen had a significant effect on pn and Ci.In the coupling effect,the two interactions between the three factors of water,nitrogen and phosphorus had no significant effect on the four indexes of photosynthesis of Camellia nitidissima.(3)The trend of chlorophyll a,b and chlorophyll content of Camellia nitidissima was consistent from the whole.The effect of nitrogen and phosphorus on chlorophyll a was greater than that of water and phosphorus.The interaction between water and phosphorus had a significant effect on chlorophyll b.The effect of nitrogen and phosphorus interaction on chlorophyll content was higher than that of water and phosphorus.Under the same fertilization level,the content of chlorophyll was low in soil water content.Water factor had a significant effect on the maximum photochemical efficiency(Fv/Fm)of PS ?.The interaction between the three groups had no significant effect on Fv/Fm.(4)Drought stress is more serious,MDA content is the highest;water and fertilizer more adequate treatment,the lowest content of malondialdehyde.The effect of nitrogen on the significant effect of MDA was greater than that of water.The coupling effect of the three factors had no significant effect on the malondialdehyde.The three factors of water,nitrogen and phosphorus have significant effects on soluble sugar and soluble protein content.Both nitrogen and phosphorus interacted significantly with soluble sugar and soluble protein.(5)There were significant positive effects on total nitrogen in leaves,and the effect of P>N>W and water factor had a significant positive effect on total leaf phosphorus.Effect is greater than the effect of water on its positive effect.The effects of water and phosphorus on the total nitrogen of leaves were significantly antagonistic,and the interaction of water,nitrogen and phosphorus had significant effects on leaf total phosphorus and total potassium,and NP>WP>WN,and had synergistic effect on leaf total phosphorus,The interaction of nitrogen and phosphorus in the action of potassium in leaves was antagonistic.In the coupling effect,the leaf phosphorus content was the highest when P=1.6%and N=3.6g,W=16%and P?1.4g.(6)There was a significant positive correlation between the relative increment of plant height and relative diameter,relative leaf weight,biomass and leaf phosphorus content,and negatively correlated with MDA.There was no significant correlation between the root and shoot ratio except the transpiration rate Tr.The results showed that when the soil water content was 13.8%,the nitrogen application rate was 1.81?3.62g/plant,and the growth of Camellia nitidissima seedlings was the best when the amount of phosphorus was about 1.2g.