Bogaert Florent, Chesnais Quentin, Catterou Manuella, Rambaud Caroline, Doury Géraldine, Ameline Arnaud
Ecologie et Dynamique des Systèmes Anthropisés FRE 3498, CNRS-UPJV, Amiens, France.
UMR INRA 1281, Stress Abiotiques et Différenciation des Végétaux Cultivés, Université Lille Nord de France, Lille, Villeneuve d'Ascq, France.
Pest Manag Sci. 2017 Aug;73(8):1648-1654. doi: 10.1002/ps.4505. Epub 2017 Feb 3.
The use of nitrogen fertiliser in agrosystems can alter plant nitrogen and consequently improve nutrient availability for herbivores, potentially leading to better performance for herbivores and higher pest pressure in the field. We compared, in laboratory conditions, the effects of nitrogen fertilisation on a promising biomass crop, Miscanthus × giganteus, and its parents M. sinensis and M. sacchariflorus. The plant-mediated effects were compared on the second trophic level, the green corn leaf aphid Rhopalosiphum maidis.
Results showed that the biomass and leaf C:N ratio of M. sinensis plants treated with nitrogen fertiliser were significantly greater than those of non-treated plants. As regards M. × giganteus and M. sacchariflorus, the only reported change was a significantly smaller leaf C:N ratio for treated M. sacchariflorus compared with non-treated plants. Surprisingly, nitrogen fertilisation had opposite effects on plant-herbivore interactions. Following nitrogen treatments, M. sinensis was less suitable in terms of intrinsic rate of increase for R. maidis, the feeding behaviour of which was negatively affected, while M. sacchariflorus and M. × giganteus exhibited greater suitability in terms of aphid weight.
Nitrogen fertilisation had contrasting effects on the three species of Miscanthus plants. These effects cascaded up to the second trophic level, R. maidis aphid pests, either through a modification of their weight or demographic parameters. The implications of these results were discussed in the context of agricultural sustainability and intensive production practices. © 2016 Society of Chemical Industry.
在农业系统中使用氮肥会改变植物的氮含量，从而提高食草动物可利用的养分，这可能会使食草动物表现更好，但也会导致田间害虫压力增大。我们在实验室条件下比较了氮肥对一种有前景的生物质作物芒草（Miscanthus × giganteus）及其亲本中华芒草（M. sinensis）和荻草（M. sacchariflorus）的影响。在第二营养级，即绿玉米叶蚜（Rhopalosiphum maidis）上比较了植物介导的效应。
结果表明，施氮肥处理的中华芒草植株的生物量和叶片碳氮比显著高于未处理植株。对于芒草和荻草，唯一有报道的变化是，与未处理植株相比，施氮肥处理的荻草叶片碳氮比显著更小。令人惊讶的是，氮肥对植物与食草动物的相互作用有相反的影响。经过氮肥处理后，中华芒草对玉米叶蚜的内禀增长率而言不太适宜，玉米叶蚜的取食行为受到负面影响，而荻草和芒草对蚜虫体重而言表现出更高的适宜性。
氮肥对三种芒草植物有不同的影响。这些影响通过改变蚜虫的体重或种群统计学参数，一直级联到第二营养级，即玉米叶蚜害虫。在农业可持续性和集约化生产实践的背景下讨论了这些结果的意义。© 2016化学工业协会。
