Le but de cette étude était de vérifier si une pulvérisation précoce de nitrate de potassium et de surfactant (NP+S) sur les pacaniers augmenterait le rendement en noix. Les traitements n’ont pas influencé les composantes du rendement, la nutrition en K ni la photosynthèse nette, mais ont éliminé une population de pucerons jaunes des pacaniers. Des pulvérisations d’eau seule ont éliminé des pucerons, et l’ajout de KNO3 (0,5 %) et de surfactant (0,15 %) a augmenté l’efficacité de l’élimination (Figure 1).
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Figure 1. Influence des pulvérisations foliaires sur les populations jeunes de pucerons jaunes des noix de pécan sur le feuillage des pacaniers 1 jour après pulvérisation. Traitements : témoin (pas de pulvérisation), eau, NP (nitrate de potassium) et S (surfactant : détergent Sears à base de phosphate trisodique).
Wood, B. W., J.A. Payne et M.T. Smith. 1995. Suppressing pecan aphid populations using potassium nitrate plus surfactant sprays. HortScience, 30 (3): 513-516.
