Effects of Nitrogen Form and Application Rates on the Growth of Petunia and Nitrogen Content in the Substrate

• Published in: Communications in Soil Science and Plant Analysis 2013, Vol.44 (1-4), p.473-479
• Main Authors: Ramos, Lucia, Bettin, Andreas, Herrada, Blanca Maria Plaza, Arenas, Teresa Lao, Becker, Silvia Jiménez
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; application rate; Biological and medical sciences; buds; color; Dark storage duration; fertigation; Fundamental and applied biological sciences. Psychology; greenhouses; leaves; mineral nitrogen; nitrate reduction; nitrates; nitrification inhibitor; nitrification inhibitors; nitrogen; nitrogen content; nitrogen fertilizers; nutrient solutions; Petunia; Petunia hybrida; storage conditions
• ISSN: 1532-2416; 0010-3624; 1532-2416; 1532-4133
• DOI: 10.1080/00103624.2013.744147

Fertigation practices have been proposed for decreasing nitrogen (N) leaching losses and for nutrient efficiency increase, including the use of nutrient solutions with low concentrations of N and the application of nitrification inhibitors with ammonium ammonium (NH₄⁺) N fertilizers. The effects of N form, application rates, and use of an inhibitor of nitrification [3,4- dimethylpyrazole phosphate (DMPP)] on the growth and the N percentages in leaves of Petunia × hybrida, as well as the N content in the substrate, were tested. Plants were placed in a venlo-glass greenhouse. Five treatments were established, changing N form, application rates, and with or without the inhibitor of nitrification: T1, 120 mg L⁻¹ of N- nitrate (NO₃⁻); T2, 120 mg L⁻¹ of N-NH₄⁺; T3, 80 mg L⁻¹ of N-NH₄⁺ with DMPP; T4, 120 mg L⁻¹ of N-NH₄⁺ with DMPP; and T5, 160 mg L⁻¹ of N-NH₄⁺ with DMPP. Nitrogen form did not have an effect on plant dry and fresh weight, plant height, or number of buds; however, ammonium treatments increased ammonium concentration and reduced nitrate concentration in the substrate solution. The use of DMPP achieved a significant reduction in nitrate concentrations in the substrate solution. Nitrogen percentage in leaves was not affected by N form, whereas the leaves of the plants treated with ammonium showed an increase in color, probably due to an increase in iron concentration. Ammonium fertilization increased the percentage of plants that survived in dark storage conditions.