Résumé: Wheat (Triticum sativus L.) seedlings of 6 days were transplanted and used to study effects of doses and fertilizer forms of phosphorus in the chlorophyll a fluorescence, leaf reflectance and other physiological and morphological parameters. Plants were raised in hydroponic culture. As it is known that phosphorus is an essential macronutrient for plant growth, and its deficiency limits plant productivity. Recent research has shown that chlorophyll a fluorescence and leaf reflectance analysis can be used as a sensitive indicator of latent P deficiency in a variety of plant species. In the present study we showed that, chlorophyll a fluorescence OJIP transients and plant leaf spectra in the vis-NIR regions are powerful tools for detecting P deficiency in wheat directly in the plant. The results showed a difference on the I and P steps on the OJIP transient in phosphorus plants deficient (-P) compared to the plants grown under P sufficient conditions. Besides the indirect effect of P starvation on pigment absorption in the near-infrared region, it was found that P deficiency also affected the stomatal conductance. However no effect was noticed on chlorophyll content index.In addition to physiological parameters, deficit on phosphorus has also affected some morphological ones. In fact, the induction of some forms of root hairs and the increase in root growth parameters are the most noticeable changes in root architecture caused by phosphorus deficiency. This was to the detriment of shoot growth, which was smaller

Encadrant: RACHIQ, S

Jurry: - Pr. RACHIQ.S - Pr. OUKARROUM.A - Pr. BENJELLOUN.M - Pr. MIKOU.K