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911.
912.
Summary Experiments were conducted to determine the influence of N, P, and K and of the NP and NK interactions on root yields and
tissue concentrations of N, P, and K of rutabagas grown on a sandy loam soil under greenhouse conditions. Root yields were
increased by applications of N and K but not by added P. The yield response to N was dependent on K supply. The highest dry
matter content in roots was associated with the lowest rates of N and K and the lowest root yields.
The N content of tissue at the early vegetative stage increased with increasing rates of N and decreased with increasing rates
of P and K. The N content of root tissue at harvest increased at the highest rates of N but was unaffected by rates of P and
K. The P and K content of root tissue increased with increasing rates of P and K, respectively.
The levels of nutrients in early vegetative tissue associated with optimum yields were about 2.6, 0.24, and 2.0% for N, P,
and K, respectively. The corresponding values in the leaf tissue at harvest were about 1.2, 0.12, and 1.5% N, P, and K, respectively.
Contribution No.222. 相似文献
913.
Brother and sister with trisomy 10p: a new syndrome 总被引:4,自引:0,他引:4
914.
915.
916.
R Parrilla K Okawa K O Lindros U J Zimmerman K Kobayashi J R Williamson 《The Journal of biological chemistry》1974,249(15):4926-4933
917.
918.
919.
920.
The localization ofl-asparaginase (l-asparagine amidohydrolase, EC 3.5.1.1) EC-2 isoenzyme was studied inEscherichia coli ATCC 9637 grown under conditions of moderate aeration. The enzyme was determined in cell fractions obtained by fraction centrifugation
of lysed spheroplasts. When the synthesis of the enzyme was induced byl-asparagine, its amount in the cytoplasmic fraction at the beginning of the induction exceeded as much as five times that
in uninduced cells, attaining up to 20% of the total activity. In the course of growth of the culture this activity decreased
gradually to zero. The membrane fraction of induced cells contained considerable amount of EC-2l-asparaginase which, at the beginning of the induction, reached up to 6% ot the total enzymic activity; in membrane fraction
of control cells the activity was close to zero. The results indicate a relationship of cell structures to thel-asparagine-induced synthesis of the enzyme. 相似文献