Partition of biomass and nitrogen in a potato crop under three nitrogen fertilization treatments

Abstract

Nitrogen nutrition considerably influences the process of growing and producing potato crops. The aim of this study was to determine the effects of nitrogen nutrition on the pattern of biomass and nitrogen partitioning during the growth of potato crop in Mérida, Mérida, Venezuela. Experimental land plots were set, with a randomized blocks design, and with three different fertilization treatment settings for the "Granola" cultivar. The first one without nitrogen (0-N), the next one with 133 Kg N Ha-1 (133-N), and the last one with 400 Kg N Ha-1 (400-N). In the main phenological stages of the crop, biomass and nitrogen levels were measured for each organ. The performance of the tubers and the total biomass are strongly influenced by the availability of nitrogen and assimilatory biomass. The total biomass production, as well as the biomass and nitrogen partitioning to each organ, showed the following sequence: 400-N > 133-N > 0-N. However, biomass and nitrogen partitioning to the roots and stolons was higher in the treatment with limited nitrogen levels. Proportional changes among aboveground and belowground biomass are adaptive responses to nitrogen deficit conditions, which, in their turn, are determining factors in crop production.

Effects of nitrogen fertilization on the photosynthesis and biomass distribution in a potato crop

“…The different letters indicate that there are significant differences between treatments per sampling period (p <0.05). a plastic response of acclimation to stress due to N deficit (Villa et al, 2020). Additionally, these results are very consistent with previous results provided by several review and research works dealing with other vegetal species (Lambers et al, 1998;Forde, 2002).…”

“…The samplings were taken during the main phenological stages of the crop: near the moment of emergence, on the 36th day after sowing (DAP), at the beginning of tuberization (60 DAP), at the time of maximum leaf expansion (105 DAP), and at harvest (127 DAP). Thus, number of stem, plant height and biomass was determined in each phenological stage from six plants selected in each plot, with the exception of the last sampling where ten plants per plot were harvested, given the significance of the crop yield from the agronomic point of view (Villa et al, 2020). Samples of biomass were dried at 70°C until they reached a constant weight; subsequently, these samples were weighted and milled to further obtain composite samples per plot and sampling session.…”