| Soybean is a major food crop in the northeast of China with low yields.In order to explore the response of different genotypes of soybean to N,P and K deficiency,a long-term continuous crop localization trial of soybean was established in the Gongzhuling Ecological Experiment Area,using four different genotypes of soybean varieties"Jilin 30","Jiyu 86 The experiment was conducted in Gongzhuling Ecological Experiment Area,using four soybean varieties of different genotypes"Jilin 30","Jiyu 86","Changnong 13"and"Hybrid Bean No.5"as test materials.The dry matter accumulation of soybean was analysed throughout its reproductive period,photosynthetic characteristics were analysed at the R4 and R6 stages,and agronomic traits,yield and yield components and fertiliser contribution were analysed at maturity:(1)among different varieties of soybean chlorophyll content and nitrogen balance index,Jilin 30 chlorophyll content and nitrogen balance index were significantly different in PK and NPK treatments compared with CK treatment;Jiyu 86 chlorophyll content and nitrogen balance index were significantly different in PK treatment compared with CK treatment;Changnong 13 chlorophyll content was significantly different in PK,NK,NP and NPK treatments compared with CK treatment,and nitrogen balance The differences in chlorophyll content and nitrogen balance index between PK,NK and NPK treatments and CK treatments were significant;the differences in chlorophyll content and nitrogen balance index between PK and NPK treatments and CK treatments were significant for hybrid bean 5.The differences in chlorophyll content and nitrogen balance index between PK and CK treatments were not significant for Jilin 30 and Jiyu 86,while the differences in chlorophyll content and nitrogen balance index between NPK and CK treatments were significant for the other two varieties.(2)The net photosynthetic rate,transpiration rate and stomatal conductance of Jilin 30 and Jiyu 86 were PK>NPK>NK>NP>CK,with the opposite pattern of intercellular CO2 concentration;the net photosynthetic rate,transpiration rate and stomatal conductance of Chang Nong 13 and Hybrid Bean 5 were NPK>PK>NK>NP>CK,with the opposite pattern of intercellular CO2 concentration.(3)The variation pattern of intercellular CO2 concentration was the opposite.(3)The dry matter accumulation of different varieties of soybean showed an overall single-peak curve change,reaching a peak at the R6 stage of soybean and then gradually declining,with different varieties showing different rates of senescence and dry matter decline.The dry matter of Jilin 30 and Jiyu 86 soybean plants was significantly higher in the R6 period than in the other treatments;Chang Nong 13 and Mixed Bean 5 soybean plants were significantly higher in the NPK treatment than in the other treatments.dry matter of soybean plants of different varieties in the R6 period showed that Mixed Bean 5>Jiyu 86>Jilin 30>Chang Nong 13.(4)Among the agronomic traits of different soybean varieties,the stem thickness of Jilin 30 and Jiyu 86 were 9.02cm and 8.71cm,the bottom pod height was 34.5cm and 38.60cm,the plant height was 117.50cm and 103.56cm,the number of main stem nodes was 18.38 and 17.13,and the stalk weight was 14.96g and 10.48g,respectively.The stem thickness of Chang Nong 13 and Hybrid Bean No.5 was 8.30cm and 9.88cm respectively,the bottom pod height was 23.20cm and 20.10cm respectively,the plant height was 115.50cm and 89.81cm respectively,the number of main stem nodes was 15.94 and 17.00 respectively,and the stalk weight was 9.59g and 15.99g respectively.(5)Yield and yield components varied among varieties,with Jilin 30 and Jiyu 86performing best with PK fertilization,with a grain number of 67.62 and 70.52 per plant,a grain weight of 13.10g and 14.50g per plant,a 100-grain weight of 24.04g and 21.51g per plant,a pod number of 29.40 and 28.43 per plant,and a pod dry weight of 19.20g and 19.32g respectively,with yields of 1227.63 kg/hm~2 and 1471.00 kg/hm~2 respectively;The best performance of Chang Nong 13 and Hybrid Bean 5 was achieved with NPK fertilizer,with 91.70 and 262.83 grains per plant,11.77g and 28.05g grain weight per plant,21.61g and 19.61g 100 grain weight per plant,33.72 and 67.30 pods per plant,17.15g and 40.06g dry weight per pod,The yields were 1610.00 kg/hm~2 and 1764.11 kg/hm~2 respectively.(6)There were significant differences in the contribution of different fertilisers.Among the three fertilisers,potassium fertiliser contributed the most to the crop yield,with 13.0%for Jilin30,10.3%for Jiyu 86,11.4%for Changnong 13 and 7.7%for Hybrid Bean 5.In summary,the physiological characteristics,agronomic traits,yield and yield components of soybean were least affected by the nitrogen deficiency treatment,and the lowest contribution of nitrogen fertilizer could be seen in the fertilizer contribution analysis.The effect of phosphorus deficiency on physiological characteristics,agronomic traits,yield and yield components of soybean was intermediate between N and K. |
