Preliminary Study On Relationship Between Some Physiological And Biochemical Characters And Quality And Yield In Different Peanut Varieties (Strains)

Six peanut strains (F7) and two widely cultivated varieties, i.e. Guihua 17and Shanyou 523, were compared in both greenhouse and field experiments. The photosynthetic characters in peanut leaf at different stages, peroxidase and esterase isozymes in peanut leaf and seed, coarse protein, coarse fattiness and fatty acid content in peanut seed were measured. The agronomic characters in crops of the two experiments, and the theoretic yield in the field experiment were surveyed. The main results were as follows:1. Through the patterns of the peroxidase and esterase isozymes, it was found that the peroxidase isozyme in peanut leaf at pod producing stage well reflected the differences of the varieties or strains. But the esterase isozyme bands in peanut seed only showed the differences of expressing rate.2. The highest photosynthetic rate was found in Shanyou 523 at three measured dates (knitting stage, pod producing stage and plump podstage) in the spring crop. And Shanyou 523 also had higher photosynthetic rate in the autumn crop. The coarse fat content was the highest in Shanyou 523 among the eight entries. The photosynthetic rate of Strain 5 was in the middle or somewhat higher levels among the eight entries in the spring crop, but the highest in the autumn crop. And Strain 5 also recorded rather high coarse fat content and the highest theoretic yield among the eight entries, which suggested that the coarse fat synthesis was related with the photosynthate production and its partition.3. Lower Fo and higher Fv/Fo were found in Guihua 17 at the plump pod stage, and higher Fv/Fm in Guihua 17 at the three measuring dates (knitting stage, pod producing stage and plump pod stage) as compared with other entries. The coarse protein content was the highest in Guihua 17among the eight entries in the spring crop, and it was third, just behind of that in Shanyou 523 and Strain 3 in the autumn crop, and that in Guihua 17 showed very little difference in the two crops. Lower Fo and higher Fv/Fo and Fv/Fm were also found in Strain 3. And the coarse protein content in Strain 3 was No.2, only lower than that in Guihua 17, in the spring crop, but the highest among all in the autumn crop. The coarse fat content in Strain 3 was higher in the spring crop which had more diseases and insect pests than in the autumn crop, suggesting that the coarse protein synthesis was relative with the light energy utilization in peanut.According to the above results, we concluded that the coarse proteinand coarse fat contents were closely related with the photosynthesis at different growth stages. The peroxidase and esterase isozyme bands showed that the characters in strains of the six generation (F7) were already stable enough for variety identification.