HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Figures Only Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in ISI Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Faye, I. Articles by Diallo, N. Search for Related Content PubMed Articles by Faye, I. Articles by Diallo, N. Agricola Articles by Faye, I. Articles by Diallo, N. Related Collections Nutrient Management Root Growth Root Development Phosphorus

Phosphorus Management

Characterizing Root Responses to Low Phosphorus in Pearl Millet [Pennisetum glaucum (L.) R. Br.]

^a Centre d'Etude Régional pour l'Amélioration de l'Adaptation á la Sécheresse (Ceraas/Isra/Coraf), BP 3320 Thies Escale, Thies, Senegal
^b Département de Biologie Végétale, Faculté des Sciences et Techniques, Université Cheikh Anta Diop de Dakar

^* Corresponding author (omdiouf{at}yahoo.fr)

Received for publication July 1, 2005. Adaptation to low water and soil P availability has been related to root properties. Two experiments were conducted in a greenhouse. Under hydroponics conditions, plants of the Souna 3 cultivar were grown for 30 d with three levels of P (P0 = 0.0 mol L^–1, P1 = 0.073 10^–3mol L^–1, and P2 = 1.65 10^–3 mol L^–1). In the pot experiment, two cultivars (Souna 3 and IBMV8402) were planted in pots filled with 19 kg of P-deficient and sandy soil and subjected to two watering regimes: well watered and water stressed at the vegetative phase from 23 d after sowing (DAS) to 30 DAS. Phosphorus treatment consisted of two levels: application of phosphate fertilizer (P₂O₅) at the rate of 649 mg per pot (34 mg P₂O₅ kg^–1 soil), referred to as F1, and no phosphate application, referred to as F0. The results showed that under P deficiency, pearl millet [Pennisetum glaucum (L.) R. Br.] presented an alteration of root parameters, particularly root volume, by the formation of root hair. Under non-water-limited conditions as well as in high or low P, IBMV8402 showed a better root and shoot growth. However, under drought conditions, the leaf water potential (_f) of IBMV8402 (_f = –5 MPa) decreased more than that of Souna 3 (_f = –3 MPa). In spite of this, P supply improved the root and shoot growth of IBMV8402. Finally, except for the condition of water stress and without P supply, P utilization efficiency exhibited by IBMV8402 was 20 to 50% higher than that of Souna 3 on the basis of shoot biomass production.

Abbreviations: DAS, days after sowing • NbAR, number of adventitious roots • RB, root biomass • RV, root volume • SB, shoot biomass • SFI, structure function index • STR, water stressed • WW, well watered • P0 = PHI(P0) = Fv/Fm, maximum quantum yield of PSII photochemistry