Nutrient limitations in the northern pitcher plant Sarracenia purpurea

Abstract

The idea that carnivorous plants capture insects to supply limiting nutrients is often conjectured but rarely tested with fertilization trials or the construction of nutrient budgets. Accordingly, Sarracenia pupurea plants were analyzed for nitrogen and phosphorus after a 4-month fertilization of the pitchers with nitrogen, phosphorus, micronutrients, combinations thereof, and insect material. Neither the number of leaves produced in the same season nor average leaf mass differed significantly between treatments. Nitrogen and phosphorus concentrations were significantly higher in those leaves that received the respective treatments. Plots of concentration versus content indicated that plants were nitrogen and phosphorus limited. A nutrient budget for nitrogen was determined by soil mineralization, insect removal from the pitchers, and rainwater analysis. This budget showed that nitrogen in captured insects is one-tenth the annual plant requirement. However, soil N mineralization is sometimes more than adequate to supply demands were it to be exploited.R&sum& : On accepte gCnCralement l'idte que les plantes carnivores capturent des insectes pour y trouver les nutriments qui limitent leur croissance, mais peu de donnCes viennent dlexpCriences de fertilisation ou de 1'6tablissement de bilans nutritifs. ConsCquemment, l'auteur a effectuC des analyses d'azote et de phosphore, 4 mois aprbs la fertilisation de sarracCnies avec de l'azote, du phosphore, des micronutrients et une combinaison de ces derniers en plus de tissus d'insectes. Ni le nombre de feuilles produites au cours de la mCme saison, ni le poids moyen des feuilles diffkrent significativement entre les traitements. Les teneurs en azote et en phosphore sont significativement plus ClevCes dans les feuilles qui ont r e y ces traitements, respectivement. Un graphique representant les concentrations versus le contenu indique que la croissance des plants Ctait limitCe par l'azote et le phosphore. Une bilan nutritif de l'azote i Ct C constituC en dCterminant la mineralisation Cdaphique, la rCcupCration des insectes dans les rCservoirs foliaires et l'analyse de l'eau de pluie. Ce budget montre que l'azote captC dans les insectes reprCsente un dixibme des besoins annuels de la plante. Cependant, l'azote provenant de la minkralisation est quelques fois plus que suffisant pour les besoins lorsqu'il est exploit&.

Foliar Reflectance and Vector Analysis Reveal Nutrient Stress in Prey- Deprived Pitcher Plants (Nepenthes rafflesiana)

“…Increased foliar concentrations of these elements as a result of digesting insect prey have been reported for Sarracenia spp. (Christensen 1976;Chapin and Pastor 1995), Pinguicula vulgaris (Aldenius et al 1983), and Drosera sp. (Chandler and Anderson 1976).…”

“…However, while the benefits of prey capture are documented for other carnivorous plant families (Sarraceniaceae [Christensen 1976;Chapin and Pastor 1995], Lentibulariaceae [Aldenius et al 1983], Droseraceae [Chandler and Anderson 1976;Wilson 1985;Thum 1988;Schulze and Schulze 1990;Gibson 1991;Karlsson and Pate 1992] thes species to investigate this aspect of their biology. We explored this question by assessing the consequences of zero prey capture to N. rafflesiana in its natural habitat via analysis of pitcher production, tissue nutrient status, and foliar reflectance.…”

Effects of supplementary nitrogen on biomass and nitrogen accumulation in the sundew Drosera capensis L.

“…The study by Chapin and Pastor (1995) capensis during our experiment may directly be correlated to trap and absorption mechanisms. As well, in other studies, the supplementary nitrogen source had been added in different forms and, in many cases, with other nutrients, suggesting a possible link between combinations of nutrients being more effective (Hanslin and Karlsson 1996;Adamec 2002;Adamec 1997;Zamora et al 1997).…”

“…This indicates that D. capensis did not benefit in biomass from supplementary nitrogen as control plants grew apparently as well as those receiving supplementary nitrogen. Chapin and Pastor (1995) also showed that S. purpurea did not differ in terms of biomass as compared to the control when supplemented with an N~CI fertilizer into the pitchers. These results suggest three possibilities: 1) the concentration of N~CI was not high enough to show effective results; 2) the fertilizer N~CI is not effective in terms of biomass production and may require the presence and/or action of other nutrients which could lead to increased biomass or 3) the fertilizer N~CI is not readily taken up by the absorbing mechanisms found on the leaves of D. capensis.…”

“…A solution of 157 .6mM of NI4Cl was created in an attempt to simulate this percentage into a working form. This solution was used in a previous supplement feeding experiment on Sarracenia purpurea (Chapin and Pastor 1995). Thirty-six plants were divided into 6 treatment groups, each consisting of 6 plants and numbered accordingly.…”