Yield components and quality parameters of winter wheat depending on tillering coefficient
¹Latvia University of Agriculture, Faculty of Agriculture, Liela street 2, LV–3001, Jelgava, Latvia
²Latvia University of Agriculture, Faculty of Information Technologies, Liela street 2, LV–3001, Jelgava, Latvia
Winter wheat (Triticum aestivum L.) is the main and most profitable cereal crop in Latvia, thus different aspects of its growth are widely researched. The aim of this three-year (2004–2005 and 2006–2007) long investigation arranged at Research and Study farm ‘Peterlauki’ of Latvia University of Agriculture (56 30.658 N and 23 41.580 E) was to evaluate importance of tillering for wheat yield, yield components and quality formation alongside the effect of cultivar, sowing date and rate, and research year. Three cultivars (‘Cubus’, ‘Tarso’, ‘Zentos’), four sowing dates (starting with 30 August ± 2 days with 10-day intervals) and three sowing rates (300, 400 and 500 germinable seeds m-2) were used. Soil and crop management was appropriate. Yield components were detected from sample sheets. Yield was affected substantially (p < 0.05) by all the investigated factor except sowing rate. Plants with tillering coefficient (TC) ‘1’ to ‘6’ formed yield, and the biggest proportion (20%) was given by plants with TC ‘3’. Grain number and weight per spike was substantially (p < 0.01) affected by TC, but changes in their values were irregular and further investigations are needed. Average values of crude protein, gluten and starch content, Zeleny index and 1,000 grain weight was not affected by TC substantially. Thus, tillering was found beneficial for winter wheat yield formation as part of yield compensation mechanism. Sowing rate was the least yield, its components and quality affecting factor, but environmental conditions (research year) – the most affecting factor. The effect of cultivar and sowing date was mostly substantial, but dependent on evaluated parameter.