In:
Agronomy Journal, Wiley, Vol. 100, No. 4 ( 2008-07), p. 1101-1105
Abstract:
A presidedress soil nitrate test (PSNT) can be used to evaluate preplant N applications as a complementary method to N budget in maize ( Zea mays L.) under different management practices. Narrow rows have shown increased N accumulation and recovery efficiency by maize, and therefore soil NO 3 − –N critical concentration (CC) for maximum yield could be lower than in conventional row spacing. An experiment was performed at Balcarce (Argentina) in 1996–1997, 1999–2000, and 2000–2001 to evaluate the PSNT for irrigated no‐till (NT) maize with different row spacings (70, 52, and 35 cm) and N rates (0, 90, 140, and 180 kg N ha −1 ). Soil samples were collected to a 30‐cm and 30‐ to 60‐cm depth when maize was at the six‐leaf stage (V6). Grain yield was significantly increased by narrow rows mainly at low N availability. Relative yield was highly associated ( r 2 = 0.73 and 0.68) with soil NO 3 − –N concentration (0–30 cm) at V6 for conventional and narrow rows, respectively. Soil NO 3 − –N concentration for maximum yield (95%) was greater for conventional row spacing (22 mg kg −1 ) compared with narrow rows (17 mg kg −1 ). The reliability of the PSNT ( r 2 ) did not improve when sampling was done up to a 60‐cm depth. These results confirm the hypothesis that the NO 3 − –N CC determined for the PSNT is lower for maize crops growing in narrow rows than conventional row spacing. Narrow rows maize is a simple management practice that could contribute to enhancing system sustainability.
Type of Medium:
Online Resource
ISSN:
0002-1962
,
1435-0645
DOI:
10.2134/agronj2007.0130
Language:
English
Publisher:
Wiley
Publication Date:
2008
detail.hit.zdb_id:
1471598-3
