Effect of soil tillage, crop rotation and nitrogen application rates on grain yield of spring wheat (Triticum aestivum L.) in the Swartland wheat producing area of the Republic of South Africa

Abstract

Studies on spring wheat yield components were conducted during the 2000 and 2001 growing seasons only, while grain yield responses to tillage, crop rotation and N rates during these years were compared to the mean yield for the years 1992, 1994, 1996 and 1998 at Langgewens Experimental Farm in the Western Cape as part of a long-term tillage and crop rotation trial. Four tillage methods, namely conventional tillage (CT), tine tillage (TT), minimum tillage (MT), and no-tillage (NT) were compared. Crop rotation systems used were continuous wheat (WW) and wheaUlupin/wheaUcanola (WLWC). Three rates of N fertilisers (60, 100 and 140 kg N ha -1 ) were applied. Tillage methods had a significant effect on the number of spikes m-2 , spikelets per spike and number of kernels per spike in both the 2000 and 2001 growing seasons. Thousand kernel mass was not sig-. nificantly affected by different tillage methods in both seasons. Mean grain yield for the years 1992, 1994, 1996 and 1998 did not differ Significantly as a result of different tillage methods, but differences due to tillage methods were found in both the 2000 and 2001 growing seasons. Crop rotation had no significant effect on the mentioned yield components. Significantly higher mean yield for the years 1992, 1994, 1996 and 1998 were produced when wheat was rotated with lupins and canola (WLWC) compared to monoculture wheat (WW). Application of different rates of N had no Significant effect on the number of spikes m-2 , number of spikelets per spike and 1000-kernel mass in both growing seasons. While higher rates of N increased the number of kernels per spike in 2001 growing season, no significant differences were observed .between different N rates in the dry seasori (2000) and the results even indicated a decrease in yield with increasing N rates in 2000. Higher grain yields were obtained by application of higher rates of N fertiliser during the wet season 2001, but significant tillage x crop rotation and tillage x nitrogen interaction for the mean grain yield during the 1992-1998 period indicated that yield responses to tillage were related to soil conditions. 7

Response of Wheat Productivity to Different Rates of Compost and Ni-trogen Fertilizer Under New Valley Conditions

“…-1 increased yield and its attributes of wheat in both growing seasons. This was in accordance with results of Saleh (2002), Salem (2005), Maali and Agenbag (2004), Saad (2007), Abedi et al (2010) andAbd El-Razek andEl-Sheshtawy (2013).…”

“…-1 increased yield and its attributes of wheat in both growing seasons (Noureldin, Nemat, et al, 2013). On the other hand, the application of different N rates had no significant effect on the number of spikes m -2 , number of spikelets spike -1 and 1000-kernel mass in both seasons (Maali and Agenbag, 2004). Therefore, the present work was undertaken to determine the quantitative requirements different rates of compost and N fertilization limits in relation to grain yield response under New Valley condition.…”

Nitrogen fertilizer influence on winter wheat yield and yield components depending on soil tillage and forecrop

“…But, in general, wheat produced in the rotation with lupin (Lupinus sp.) and oilseed rape produced (Maali & Agenbag, 2013). Our study results indicate that average TGW decreased when wheat was grown after wheat.…”

Effects of Long-Term (44-years) Tillage Sequences on Wheat Grain Yield in a Dryland Farming System in South Africa

“…The trial site has a 300 mm shallow lithic soil, locally known as a Glenrosa-soil form (Soil Classi cation Working group 1991) or internationally, as Haplic Cambisols (IUSS Working Group WRB 2015). The soil has a 14.7% clay content (excluding the gravel and stone content), whilst the gravel and stone content in the A horizon is about 45% (Maali and Agenbag 2003).…”