Canola-quality white mustard: Agronomic management and seed yield

Abstract Modern white mustard (Sinapis alba L.) cultivars have high concentrations of erucic acid and glucosinolates. The progress in the breeding and cultivation of oilseed crops has contributed to the development of canola-quality white mustard, a variety without erucic acid and with low glucosinolate content, which was released for commercial production in 2012. The introduction of a new variety of white mustard could require partial or complete modification of the relevant production technology. The agricultural requirements of new crop cultivars can be rapidly assessed in experiments with fractional factorial design. In 2016–2018, a field experiment with mixed 2m3k−1 factorial design, where five factors were tested at two and three levels, was carried out in the Agricultural Experiment Station in Balcyny in north-eastern Poland. Two white mustard cultivars, including the traditional cultivar Radena and the canola-quality cultivar Warta, were sown on three dates: the optimal date (4–10 April), as well as 7 and 14 days past the optimal date. White mustard cultivars were grown at three levels of agricultural inputs (0, 1, 2) with different rates of nitrogen (80, 120 and 160 kg ha-1), sulfur (0, 20 and 40 kg ha-1) and boron fertilizers (0, 150 and 300 g ha-1). The yields of the traditional cultivar exceeded those of the canola-quality cultivar by 0.53 Mg ha-1 on average. Both cultivars produced the highest yields when sown on the optimal date. Delayed sowing (by 7 and 14 days) contributed to the greatest decrease in yield (32 % and 42 %, respectively) in a dry year (2018). The traditional cultivar was more sensitive to delayed sowing than the canola-quality cultivar. In both analyzed cultivars, nitrogen fertilizer delivered yield-forming effects up to the rate of 80 kg ha-1 (in the dry year) or 120 kg ha-1 (in the year with above-average precipitation, 2016–2017). In both cultivars, a significant increase in seed yield was observed in response to 20 kg S ha-1. Foliar application of boron fertilizer did not increase white mustard yields.