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

This Article Abstract 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 ISI Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Duru, M. Search for Related Content PubMed Articles by Duru, M. Agricola Articles by Duru, M. Related Collections Forage Management Grazing Management Nitrogen

Simplified Nitrogen Assessment of Orchardgrass Swards

UMR INRA-ENSAT ARCHE, Chemin de Borde Rouge, BP27, 31326 Castanet Tolosan, France

View larger version (25K): [in a new window]   Fig. 1. Sward N index for the six experiments (see Table 1). Treatments with high (>80 kg ha–1) N added are indicated by •, , and while those with low (0–80 kg ha–1) N added are indicated by , , and . Circles and squares are for light (L) and heavy (H) defoliation treatments, respectively, at Auzeville; squares, circles, and triangles are different swards in Aveyron; vertical bars represent the standard error; and symbols joined by a broken line mean that measurements were done before 500 degree-days.

View larger version (41K): [in a new window]   Fig. 2. Nitrogen concentration of each sward layer (left-hand column) and contribution of each layer to the total sward herbage mass (middle column) vs. day of the year and N concentration per layer vs. sward height (right-hand column) for three experiments: a sward in Aveyron (first row), late-cutting treatments with N applied for spring growth (second row), or summer regrowth (third row) at Auzeville in 1997; Layers 1 (), 2 (•), 3 (), 4 (), and 5 () for figures with the day of year on the x-axis, Layer 1 being closest to the ground; , , , and x are data at the successive sampling dates for figures with the sward height on x-axis; and vertical bars represent the standard error.

View larger version (24K): [in a new window]   Fig. 3. Regression of N concentration in the upper sward layer (Nus) on sward N index (Ni): data before or after accumulation of 500 degree-days (DD) from the last cut for spring (•, ) and summer (, ) regrowths in Auzeville and spring growths in Aveyron (). For data where DD > 500, r2 = 0.92, n = 62, and SE = 2.8, and for data where DD < 500, r2 = 0.91, n = 12, and SE = 3.3.