Modeling Phenological Process And Morphalogical Formation In Wheat Before Wintering

In order to provide a reference for prophase management and precise planting of wheat, the experiments were carried out in LunDong area during 2007 to develop simulation models in wheat before wintering, the results showed that:First ,the models of henological development stages for wheat were constructed with the scale of hysiological development time. the predicted henological development stages included emergence stage, three leaf stage, tillering(start), tillering(prosperous) and wintering(start) stage. The data from field experiments with different genotypes,density and fertilization was used to test the model. The results showed that the absolute prediction errors for most stages of growth and development within 0~6d, and the root mean square errors (RMSE) were generally less than 4d. The model reflected an enhanced level of mechanism and application.Second, based on time-course observations on morphological characteristics of above-ground organs in wheat under different nitrogen and phosphorus rates ,fertilization and genotypes dynamic development processes of different organs with GDD as main line were simulated in 2007,through observing the Morphalogical properties (leaf length,leaf width and leaf shape) of caulises and tillers under different treatments, the change patterns of leaf morphology with growth progress and environmental factors were characterized and a dynamic model was developed to simulate and the effectiveness of nitrogen status on organ growth was quantified. The growth dynamics of leaf length could be described with a logistic model (sigmoid curve), but the final length of wheat show a disciplinary change with the fertilization rate and density change ,this is a consistant rule in different genotypes .using regression to quantify PHYLL for different genotypes .the changes of leaf length were simulated with subsection fuction and the dynamical change of leaf shape were formalizated. According to density ,The effect of nitrogen status on leaf growth was quantified by the value of nitrogen. Finally ,basing on the simulated results of leaf length and leaf width,the changes of leaf area were simulated. The model was validated with the field experiment data of LunJian 301,which has integrated Morphalogical and good growth tendency relatively. The results indicated that the average leaf length prediction errors for the first leaf ,the second leaf ,the third leaf and the first tiller of LunJian 301 under different treatments and GDD before wintering within 0~6d ,from Z-1 to 1N ,The average RMSEs were 0.11cm, 0.05cm ,0.05cm and 0.12cm respectively.The average leaf width in different leaf length prediction errors for the first leaf ,the second leaf ,the third leaf and the first tiller of LunJian 301 before wintering within 0.2cm. The average RMSEs were 0.06cm,0.14cm,0.18cm and 0.08cm respectively, the average leaf area prediction errors for the first leaf ,the second leaf ,the third leaf and the first tiller of LunJian 301 under different treatments and GDD before wintering within 0.15cm~2, and the average RMSEs of the first leaf, the second leaf ,the third leaf and the first tiller were 0.1 cm~2,0.105 cm~2,0.132 cm~2 and 0.15 cm~2, respectively. The results indicated that the present model had a good performance in predicting organ morphological growth on wheat plant, and thus lay a foundation for further constructing virtual wheat plant.Third , tiller dynamic was simulated in two aspects before wintering, there were per plant and population plants. Fibaracci equation was used to quantify tiller dynamic before wintering under ideal condition, and variety tiller potential was used to characterize genetic impact. Nitrogen deficit factors were used to conclude the regulating effect of environment. The results showed that the best simulated model was LongJian 301(W1),the worst simulated model was 1R17,the RESE were 0.09,0.19 respectively. For the veracity that came from different varieties population plants before wintering,the best was low density and without fertilizating ,the worst is low density and without fertilizating.this simulated model had a best forecast for LunJian 301(W1) before wintering,the worst was 1R17,the RMSE were 11.5×10~4/ha, 34×10~4/ha respectively.