Abstract:

Abstract: In this paper, computer was used for regulating the nutrition solution supplying system. In order to discover the law of absorbing of inorganic nourishment of greenhouse tomato growth in soilless culture, the N、P、K concentrations in tomato leaf were measured at different growth stages. It can supply support for nutrition solution regulation with soilless culture. The consequence was that there was no significant difference in N, P, K concentrations in different substrates. The result was that the accumulative trend of N was decreased, the highest content of N was 48.13 mg/g after plant out 60 days, and the lowest was 43.42 mg/g after plant out 300 days; The accumulative trend of P was increased firstly, then was decreased. The highest content of P was 6.23 mg/g after plant out 180 days, the lowest was 3.45 mg/g after plant out 300 days; The accumulative trend of K was decreased firstly, and then increased. The highest content of K was 24.96mg/g after plant out 300 days, the lowest was 8.45mg/g after plant out 120 days.