Effect Of NPK Combination On Yield And Quality Of Foxtail Millet

In order to study the effects of different N,P,and K ratios on the growth and development,yield,and quality of Nongda 8,the optimal N,P,and K ratios were selected.Under the same planting densities,an orthogonal design was used for this experiment.Nitrogen,phosphorus,and potassium are the three factors and four levels,and there are 16 different fertilization treatments.The morphological indexes such as plant height,stem diameter and leaf area,dry matter transport,chlorophyll content,transpiration rate,stomatal conductance,photosynthetic rate and chlorophyll fluorescence parameters and other photosynthetic indexes,grain quality and yield were determined by comparative analysis.The following main results are obtained:1 There was no significant difference in plant height and stem diameter between the fertilization treatments in Nongda 8 at the early stage of growth.With the subsequent shift in the growth period,the difference was gradually significant,with N4P2K3(N 225Kg·hm-2,P2O5 50Kg·hm-2,K2O60Kg·hm-2)is best dealt with.Single application of P and K fertilizers can increase the stem diameter of Nongda 8,but it has little effect on the plant height.Based on the P and K fertilizers,with the increase of N fertilizer,the Nongda 8 plant height and stem diameter can be significantly improved,which is beneficial to millet Grow.2 Nongda 8 leaf area is a dynamic growth trend that increases first and then decreases from the jointing stage to the maturity stage.The growth rate is fast and then slow,and the leaf area reaches the maximum at the flowering stage,and gradually decreases from the flowering stage to the maturity stage 16 The treatments were best treated with N4P2K3(N 225Kg·hm-2,P2O5 50Kg·hm-2,K2O 60Kg·hm-2)and were consistent with the plant height stem thickness results3 Different fertilization treatments had different but not significant effects on Nongda 8 translocation before flowering,dry matter accumulation after anthesis and contribution rate to grain.In all treatments,the dry matter accumulation after anthesis under N4P2K3(N 225Kg·hm-2,P2O5 50Kg·hm-2,K2O 60Kg·hm-2)and the contribution rate to the grain were the best and the fertilization increased.The dry matter accumulation ability of Nongda 8 after flowering is conducive to the transfer and redistribution of dry matter to grains after anthesis4 The relative chlorophyll content of the inverted two leaves of Nongda 8 showed the trend of increasing first and then decreasing,reaching the maximum at the flowering stage and gradually decreasing thereafter.Different fertilization treatments can increase the chlorophyll content of millet leaves.The chlorophyll content of millet leaves treated with N4P2K3(N 225Kg·hm-2,P2O5 50Kg·hm-2,K2O 60Kg·hm-2)has the highest chlorophyll content,which is higher than the non-fertilizer treatment,25.46-34.40%higher,reaching significant difference,and the rate of decline in the later period is lower than other treatments,the green keeping time is long-lasting,and the aging rate is slow.5 The maximum photochemical efficiency of PS?(Fv/Fm),the potential photochemical activity of PSII(Fv/Fo),the actual photochemical efficiency of PSII(Y(II)),the photosynthetic electron transport rate(ETR),and the photochemical quenching efficiency of millet leaves after fertilization qP),net photosynthetic rate,transpiration rate,and stomatal conductance were all increased compared with non-fertilized N1P1K1 treatment.Intercellular carbon dioxide concentration and non-photochemical quenching coefficient(NPQ)were decreased.Fertilization effectively increases the photosynthetic capacity of millet,so that the leaves have a higher light-capturing capacity,which accelerates the absorption and conduction of millet inorganic ions and organic matter,is conducive to the formation of photosynthetic products and promotes the transport of nutrients to the panicle kernels.The optimal combination of fertilization obtained by orthogonal analysis was N4P3K3,(N 225Kg·hm-2,P2O5 100Kg·hm-2,K2O 60Kg·hm-2).The net photosynthetic rate of Nongda 8 was the best.N had the greatest impact on the net photosynthetic rate of Nongda 8,followed by K2O,and P2O5 had the smallest influence.Under different fertilization treatments,the transpiration rate,stomatal conductance,the actual quantum yield of PSII,the relative rate of photosynthetic electron transport and the net photosynthetic rate reached a significant positive correlation,and the intercellular C02 concentration showed a significant negative correlation.The direct effect was Y(II)>E>Fv/Fm>Fv/Fo>Ci>qP>Gs>ETR>NPQ.6 Nongda 8 was higher than the N4P2K3 treatment(N 225Kg·hm-2,P2O5 50Kg·hm-2,K2O60Kg·hm-2).Spike length,panicle weight,panicle weight,ear weight,1000-grain weight and yield were higher Other processing.The production of low-nitrogen levels was lower than that of high-nitrogen levels The single application of phosphorus and potassium fertilizers was lower than that of phosphorus and potassium fertilizers,but decreased after exceeding the optimal level.Orthogonal analysis showed that N had the greatest impact on the yield of Nongda-8,followed by K2O and P2O5 had the smallest influence.The optimal combination of fertilization was N4P3K3(N 225Kg·hm-2,P2O5 100Kg·hm-2,K2O 60Kg·hm-2).7 There was a significant difference in the protein content of Nongda 8 with different fertilization treatments,and the protein content gradually increased with the increase of N application amount.At the four levels of nitrogen fertilizer,the protein content was N4>N3>N2>N1,and the best treatment was N4P2K3(N 225Kg·hm-2,P2O5 50Kg·hm-2,K2O 60Kg·hm-2).The application of nitrogen fertilizer significantly increased the protein content of Nongda 8,and the effect of P and K fertilizer on Nongda 8 protein content was lower than that of N fertilizer.The fat content of Nongda 8 was significantly different under different fertilization treatments.Irrational fertilization and excessive fertilization reduced the fat content of Nongda 8.At the four levels of nitrogen fertilizer,the fat content was N2>N3>N1>N4,and N2P2K1 treatment(N 75Kg·hm-2,P2O5 50Kg·hm-2,K2O 0Kg·hm-2)was the best,too low.The excessive nitrogen application rate will reduce the fat content of Nongda 8 and the single application of P and K fertilizers is not conducive to the accumulation of fat.Only the appropriate ratio of N,P,and K will result in high quality millet.The content of amylose in different fertilization treatments was significantly different,and the amylose content gradually decreased with the increase of nitrogen application rate.At four levels of nitrogen fertilizer,the amylose content was N1>N2>N3>N4,and N4P2K3 treatment(N 225Kg·hm-2,P2O5 50Kg·hm-2,K2O 60Kg·hm-2)was the best.This shows that fertilization can significantly reduce the content of amylose,and the appropriate ratio of nitrogen,phosphorus and potassium can improve the taste quality of millet.There was no significant negative correlation between protein content and fat content,and the correlation coefficient was 0.137.There was no significant positive correlation between amylose content and fat content.The correlation coefficient was 0.07,which was significantly negatively correlated with protein content.The correlation coefficient was 0.904.