文摘
Certain bioregulators were studied in relation to nitrogen metabolism of pepper plants (Capsicumannuum L. cv. Lamuyo). Plants were grown under controlled conditions and submitted to regularfertilization with macro- and micronutrients. Treatments were as follows: nontreated control (T0);fosfonutren [essential amino acids and micronutrients (46.9 mg L-1)] (T1); biozyme [GA3 (32.2 mgL-1) plus IAA (32.2 mg L-1) plus zeatin (83.2 mg L-1) plus chelated micronutrients] (T2); and GA3[16 mg L-1] (T3). The concentrations of NO3-, organic N, amino acids, and proteins, the activitiesof nitrate reductase (NR) and nitrite reductase (NiR), and finally the foliar dry weight and yieldwere analyzed. The results indicated that the application of certain bioregulators, such as fosfonutren(T1), which contain amino acids can cause a negative effect on the efficiency and utilization of NO3-,resulting in a drastic loss in growth and yield, even under the control treatment, in which nobioregulator was applied. On the contrary, the application of certain bioregulators based principallyon the combination of different hormones, as in the case of biozyme (T2), increased NO3- assimilationunder our experimental conditions, due possibly to a greater availability of these bioregulators inthe leaves and increased NR and NiR activities. This appears to explain why the T2 treatmentgave the greatest foliar dry weight and fruit yield per plant in the experiment.Keywords: Capsicum annuum L.; nitrogen metabolism; bioregulators; yield
