Authors:B.L. Béres, N.Z. Lupwayi, F.J. Larney, B. Ellert, E.G. Smith, T.K. Turkington, D. Pageau, K. Semagn, and Z. Wang
Research indicates that not all crops respond similarly to cropping diversity and the response of triticale (× Triticosecale ssp.) has not been documented. We investigated the effects of rotational diversity on cereals in cropping sequences with canola (Brassica napus L.), field pea (Pisum sativum L.), or an intercrop (triticale:field pea). Six crop rotations were established consisting of two, 2-yr low diversity rotations (LDR) (continuous triticale (T-T_LDR) and triticale-wheat (Triticum aestivum L.) (T-W_LDR)); three, 2-yr moderate diversity rotations (MDR) (triticale-field pea (T-P_MDR), triticale-canola (T-C_MDR), and a triticale: field pea intercrop (T- in P_MDR)); and one, 3-yr high diversity rotation (HDR) (canola-triticale-field pea (C-T-P_HDR)). The study was established in Lethbridge, Alberta (irrigated and rainfed); Swift Current (rainfed) and Canora (rainfed), Saskatchewan, Canada; and carried out from 2008 to 2014. Triticale grain yield for the 3-yr HDR was superior over the LDR rotations and the MDR triticale-field pea system; however, results were similar for triticale-canola, and removal of canola from the system caused a yield drag in triticale. Triticale biomass was superior for the 3-yr HDR. Moreover, along with improved triticale grain yield, the 3-yr HDR provided greater yield stability across environments. High rotational diversity (C-T-P_HDR) resulted in the highest soil microbial community and soil carbon concentration, whereas continuous triticale provided the lowest. Net economic returns were also superior for C-T-P_HDR ($670 ha–1) and the lowest for T-W_LDR ($458 ha–1). Overall, triticale responded positively to increased rotational diversity and displayed greater stability with the inclusion of field pea, leading to improved profitability and sustainability of the system.
Soil water balance was studied in a 25-year-old experiment, on chernozem soil, in different crop-rotation systems (mono-, bi- and triculture) in dry (2007) and rainy (2008) seasons, in maize production. Soil water deficit values in maize production were much lower in 2008 than in 2007 in non-irrigated and irrigated plots of three crop rotation systems because of favourable precipitation supply. We found difference between the water deficit values of two irrigation treatments. We measured lower values in irrigated plots of three crop-rotation systems before sowing: non-irrigated plots in monoculture 105 mm, in biculture 101 mm, in triculture 121 mm and irrigated plots in monoculture 90 mm, in biculture 91 mm, in triculture 111 mm. Soil waterstock started to decrease with the rise in average temperature and, despite an increase in precipitation quantity, we calculated higher water deficit values. Precipitation in August and the high average temperature intensified the water deficit. Water deficit showed its highest values in early September. We examined the water balance of the soil profile in 0–2.0 m and we concluded that the water deficit of the 0.8–1.2 m soil layers was most intensive in both non-irrigated and irrigated treatments, because of significant root mass. Our results showed that irrigation had a more important influence on the yield in a dry cropyear (2007 characterized by abiotic, water stress) than in an optimum water supply cropyear (2008).
Authors:Danijel Jug, Bojan Stipesevic, Ivan Zugec, Drazen Horvat, and Marko Josipovic
The trial for winter wheat (
Triticum aestivum L.
) or spring barley (
Hordeum vulgaris L.
) in rotation with maize (
Zea mais L.
) on lessive-pseudogley in semiarid to semihumid climate of Eastern Croatia was set up during years 1996–1999 with five soil tillage systems: PL) Conventional tillage based on ploughing; PD) Conventional tillage after diskharrowing for previous crop in preceding season; DP) Diskharrowing after conventional tillage for previous crop in preceding season; DD) Continuous diskharrowing, and CD) Chiselling and diskharrowing. During first and second season (1996/97 and 1997/98), recorded winter wheat grain yields were not different, with PL having the highest and DD the lowest yield. Maize showed next differences in first season: PL=PD>CH=DD=DP, and in second season PD=PL=DP=CH>DD. In 1999, spring barley replaced winter wheat, and yields were: PL>DP>PD>CD>DD. Maize yields recorded were: PL>PD>DP>CH>DD. The grain yield results, together with hectoliter mass and mass of 1000 grains, supported that PL can be replaced with other tillage systems for winter wheat and spring barley, whereas continuous diskharrowing may have substantially lower yields for maize during unfavourable years.
Authors:Saber Golkari, Jeannie Gilbert, Kirsten Slusarenko, W. Fernando, and Anita Brûlé-Babel
This study identified
spp. naturally occurring on field stubble. Throughout the 4 years of sampling, seven
species were isolated from crop stubble. In 2002 and 2003 only the stubble of foundation crops of wheat and oat were colonized by
spp; low levels were isolated from pea and canola stubble in 2005 and 2006. No consistent pattern of colonisation was observed, suggesting that airborne inoculum, susceptibility of wheat to FHB, and favorable environmental conditions are important factors in epidemics.