Translator Disclaimer
1 September 2004 Influence of method of phosphorus application on smooth pigweed (Amaranthus hybridus) and common purslane (Portulaca oleracea) interference in lettuce
Author Affiliations +
Abstract

Field trials were conducted to investigate the influence of P application method on the critical period of smooth pigweed and common purslane interference in lettuce. Studies were carried out in low-P histosols, where supplemental P fertilization is needed for lettuce production. Phosphorus was either broadcast or banded 5 cm beneath the lettuce rows at rates of 250 or 125 kg ha−1, respectively. Seedlings of either smooth pigweed or common purslane were transplanted at a density of 16 plants per 5.4 m2 (6-m row by 0.9 m wide). Weed interference duration was achieved by manual removal 2, 4, 6, or 8 wk after lettuce emergence and subsequently keeping the plot weed free until harvest. A weed-free control within each P regimen was also established. Marketable head number, head fresh yield, and head diameter were measured at harvest. Weed-free lettuce fresh yield was 20% higher with banded P than broadcast applications. In the weed–lettuce mixtures, the P regimen by weed removal interaction affected lettuce fresh yield and head diameter but not head number. Compared with broadcast P application, banded P extended the time needed to cause significant weed interference in lettuce by 10 d: from 24 to 34 d for smooth pigweed and from 37 to 47 d for common purslane.

Nomenclature: Common purslane, Portulaca oleracea L. POROL; smooth pigweed, Amaranthus hybridus L. AMACH; lettuce, Lactuca sativa L.

Bielinski M. Santos, Joan A. Dusky, William M. Stall, Thomas A. Bewick, and Donn G. Shilling "Influence of method of phosphorus application on smooth pigweed (Amaranthus hybridus) and common purslane (Portulaca oleracea) interference in lettuce," Weed Science 52(5), 797-801, (1 September 2004). https://doi.org/10.1614/WS-03-069R2
Received: 8 May 2003; Accepted: 1 March 2004; Published: 1 September 2004
JOURNAL ARTICLE
5 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top