Abstract:

The uptake rule that NPK accumulate in eggplant (Hangjia No.2008) had been investigated. The NPK content of different organs of eggplants had been analyzed during different growth stages. The results showed that the uptake amounts of K by the single eggplant was the highest (11.41 g), followed by N (4.19 g) and P (1.19 g). The percentages of NPK uptake amount at seedling stage in whole developmental stage were the least, which showed as N (3.3%), P (3.5%) and K (2.6%), respectively. Second was the early fruit stage with N (14.6%), P (10.8%) and K (16.9%), respectively. The mid fruit stage showed the highest as N (53.2%), P (68.9%) and K (55.3%), respectively. Compared to other organs, the percentages of NPK distribution in fruits was the highest, as N (53.2%), P (68.9%) and K (55.3%), respectively, while the percentages of NPK distribution in roots was the lowest. The N percentage of leaf was more than stem, while the P and K percentages of stem were more than leaf. The best curve equation of daily NPK accumulation by eggplants was cubic curve equation in the whole developmental stage, which was superior to normal linear and logarithmic equations. When the fresh eggplant yield was 3 941 kg per 667m2, the uptake amounts of N, P and K were 2.13 kg, 0.60 kg and 5.78 kg per 1 000 kg eggplants, respectively and the ratio of N, P and K uptake amount was 1.00∶0.28∶2.71．

Key words: eggplant, growth stage, organ, NPK, uptake