Agronomy Science, przyrodniczy lublin, czasopisma up, czasopisma uniwersytet przyrodniczy lublin
The effect of two factors: reduced tillage systems and foliar nutrition on soybean seed and straw yield in monoculture on lessive loess soil (good-wheat agricultural usefulness complex) in 1998–2003, is presented in the paper. The experiment was carried out by a split-block method and replicated three times on plots 35 m2 and 20 m2 for harvest. Tillage treatments: conventional (I) and 3 kinds of reduced ones: without post harvest cultivation (II); chisel+cultivator instead of ploughing and post harvest operations (III); direct drilling (diquat 600 g ha-1 in spring prior to seed drilling) (IV). Foliar application, by 2 l ha-1 of Florosol U (N – 12; P – 1.745; K – 4.981; Mg – 0.12; B – 0.012; Cu – 0.015; Fe – 0.018; Mn – 0.016; Mo – 0.002; Zn – 0.01 in % of mass), was performed twice: at 3–4 true soybean leaf and just after plant flowering. The crop was cultivated under other agrotechnical measures adjusted to its need with elementary (NPK) fertilization. Weeds were controlled by soil herbicides: linuron 450 ml + metrybuzin 210 g ha-1 and in isolated cases (in the 2002), foliar herbicide was used against Echinochloa crus -galli (L.) P. B. – 150 g ha-1 of fluazyfop P-butyl. The highest seed soybean production (2.08 t ha-1) was obtained on conventional tillage treatment (I), and a tendency to a slight yield decrease was observed only (4.8%) in the case of plough tillage before winter (II). However, chisel + cultivator (III) and direct sowing (IV) decreased the yield essentially, by about 10.1% and 26.9%, respectively, in comparison to I and II tillage system. The seed yield obtained under direct drilling (IV) was essentially lower by 23.3% and 18.7% than those obtained from II and III tillage treatments. Two-fold nutrition of soybean plants by macro- and micronutrients substantially, by 10.2%, made the yield higher. Tillage treatments did not influence substantially and clearly the yield of straw; however, the straw production was increased by foliar nutrition of soybean plants. The straw weight amounted to 1.80 to 2.05 t per ha in the consecutive years of research; only in sporadic cases to 1.12 t ha-1 (in 2002). The seed and straw yields were modified by variable weather conditions in the research years.