Effect of Planting date, Clipping Height and Cultivar on Forage and Grain Yield of Winter Wheat (Triticum aestivum L.) in Argentinean Pampas

ARZADÚN, M.J.; ARROQUY, J.I.; LABORDE, H.E.; BREVEDAN, R.E.

AGRONOMY JOURNAL

American Soc of America

Año: 2006 vol. 98 p. 1274 - 1279

0002-1962

ABSTRACT Wheat (Triticum aestivum L.) produced in the Argentinean Pampas is frequently used for dual-purpose (i.e., forage for grazing followed by grain for harvest) production.  New wheat cultivars are routinely introduced to farmers.  The objective of this 3-year study was to evaluate the effect of planting date, clipping height (simulation for grazing intensity) on forage and grain yield for three recently introduced wheat cultivars that had different morphological and physiological characteristics.  Treatments were arranged as 3 × 3 × 3 factorial distributed in a split-split plot arrangement within a randomized complete block design with four blocks.  Main plots were planting date (March, April, and May); split-plots were clipping height (3-cm, 7-cm, and no-clipping); and split-split plots were a facultative cultivar ‘Pincen’, and two non-facultative cultivars ‘Charrua’ and ‘Bordenave 223’ (‘Bve223’).  In 1995 and 1996 forage yield decreased in response to delaying planting date from March to May, whereas in 1997 forage yield was not affected by planting date.  The 3-cm clipping height yielded 21% more forage than plots clipped at 7-cm.  ‘Bve223’ and ‘Charrua’ produced significantly more forage than ‘Pincen’ each year.  Grain yield increased as planting date progressed from March to May.  Clipping, particularly at 3-cm of height, reduced grain yield compared to non clipping, while during 2-3 years, 7-cm clipping produced no significant change in grain yield compared to no clipping indicating that grazing intensity can minimize grain yield loss for dual-purpose wheat. In all years, ‘Bve223’ produced more grain than ‘Charrua’ or ‘Pincen’.  The amount of forage yield lost in response to later planting date ranged between 0 and 81% during the three years and was highly dependent upon weather conditions each year.  Contrary to the response observed for forage yield, grain yield increased from 40% to 190% for wheat planted in May compared to a March planting date.  Based on results observed in this study, dual-purpose wheat planted during April had both good forage and grain production.    And, success of dual-purpose wheat for was influenced by cultivar grown. Abbreviations DM, dry matter; CP, crude protein; NDF, neutral detergent fiber; ADF, acid detergent fiber; IVDMD, in vitro dry matter digestibility.