The influence of primary soil tillage on soil weed seed bank and weed incidence in a cereal-grass crop rotation

Abstract A field experiment was carried out at Vėžaičiai Branch of Lithuanian Research Centre for Agriculture and Forestry during the period 2008-2011. The study was aimed to determine the effects of various soil tillage methods: deep ploughing (20-25 cm), shallow ploughing (10-12 cm), shallow ploughless tillage (8-10 cm) and soil fertility improvement measures (plant residues, plant residues + straw, green manure 1 st cut + straw, green manure 2 nd cut + straw, farmyard manure 40 t ha -1 + straw) on the soil weed seed bank and weed incidence in a cereal-grass crop rotation. The soil of the experimental site is Dystric-Epihypogleyic Albeluvisol (ABg-p-w-dy) with a texture of sandy loam. In all experimental years, primary soil tillage had a significant influence on weed incidence in the crops of the rotation and on soil weed seed bank. The greatest amount of weeds, both in numbers and dry mass, in the crops of winter triticale and spring rape was determined in the shallow ploughless tillage treatment, in the crops of spring barley in the shallow ploughing treatment, and in the sward of red clover in deep and shallow ploughing treatments. All soil fertility improvement measures and their interaction with soil tillage methods did not have any substantial influence on the weed incidence in the rotation crops. The soil weed seed bank was 1.5 and 2.2 times greater in the shallow ploughing and shallow ploughless tillage treatments, compared with the conventional tillage treatment (deep ploughing). The influence of soil tillage methods manifested itself not only directly, but also through its interaction with soil fertility improvement measures. Regardless of the chosen soil fertility improvement measure, in all the treatments of shallow ploughless tillage, the soil weed seed bank was significantly greater, compared with the conventional soil tillage treatments. In the shallow ploughing and shallow ploughless tillage treatments there were found 25.5% and 41.5% more weed seed species in the soil, compared with the conventional tillage treatment. The seeds of Chenopodium album L., Persicaria lapathifolia L., Fallopia convolvulus L. and Viola arvensis Murray were found in all tillage treatments. The distribution of F. convolvulus L., P. lapathifolia L. seeds was significantly influenced by soil tillage only, that of V. arvensis Murray by soil tillage and its interaction with soil fertility improvement measures, and that of Ch. album L. by soil fertility improvement measures only

Pagrindinio žemės dirbimo įtaka dirvožemio sėklų bankui ir piktžolėtumui javų bei žolių sėjomainoje

In the shallow ploughing and shallow ploughless tillage treatments there were found 25.5% and 41.5% more weed seed species in the soil, compared with the conventional tillage treatment. The seeds of Chenopodium album L., Persicaria lapathifolia L., Fallopia convolvulus L. and Viola arvensis Murray were found in all tillage treatments. The distribution of F. convolvulus L., P. lapathifolia L. seeds was significantly influenced by soil tillage only, that of V. arvensis Murray by soil tillage and its interaction with soil fertility improvement measures, and that of Ch. album L. by soil fertility improvement measures only

Atsparios herbicidams piktžolės

Vytauto Didžiojo universitetasŽemės ūkio akademij

The Influence of Different Lenght Weedy Periods on Potato Yield

Vytauto Didžiojo universitetasŽemės ūkio akademij

Dependence of weed flora on agrochemical soil properties formed by different manure rates in acid and limed soils

Vytauto Didžiojo universitetasŽemės ūkio akademij

Changes in the soil properties as affected by conventional and minimal soil tillage systems

A stationary field trial was set up at the Vėžaičiai Branch of the Lithuanian Institute of Agriculture in 2003. The soil of the experimental site is Dystrict Albeluvisol (texture sandy light loam). The objective of the study was to estimate the effects of primary soil tillage methods on the changes in the soil structure; chemical, and biological soil properties. The field trial involved two factors: factor A – deep ploughing; shallow ploughing; shallow tillage in the autumn. Factor B – different organic fertilisers – green manure of perennial grasses, straw and manure incorporation in the crop rotation: winter wheat-spring rape – spring barley, and red clover. The herbage of the first cut and aftermath for green manure and farmyard manure were incorporated in the respective plots. The experimental findings of the first crop rotation during the period 2004–2007 are summarised in this paper. Each year, after crop harvesting the soil was limed by 400 kg ha-1 CaCO3. At the end of a four-year crop rotation in the deep and shallow ploughed soil the pH level increased by 0.2 units, while in the sallow tillage soil the pH value did not change compared with the initial level before the trial establishment. A reduction in organic carbon and nutrient content in the shallow tillage topsoil 10–20 cm layer was established. Deep and shallow ploughed soil was rich in phosphorus, potassium and nitrogen. The highest amount of nutrients was determined in the deep and shallow ploughed topsoil (0–10 cm) layer. After cultivation the structure of moraine loam soil deteriorated. A reduction in the content of water stable aggregates (>0.25 mm) by 4–7 per cent units in the tilled soil was identified compared with the ploughless tillage soil

Changes of weed infestation under long-term effect of different soil pH levels and amount of phosphorus: potassium

Lietuvos agrarinių ir miškų mokslų centro Vėžaičių filialasVytauto Didžiojo universitetasŽemės ūkio akademij

The Influence of Different Length Weedy Periods on Potato Yield

Santr. anglBibliogr.: p. 97-98 (19 pavad.)Vytauto Didžiojo universitetasŽemės ūkio akademij

Changes of weed infestation under long-term effect of different soil pH levels and amount of phosphorus:potassium

The aim of the present study was to investigate changes of weed species density as a result of long-term (1976-2005) exposure to different soil pH levels, and P2O5:K2O amount in soil created by initial and subsequent periodical liming, and fertilization. As a result of liming during the period 1976-2005, average soil pH levels at the start of the sixth crop rotation (2001-2005) ranged from 4.1 (unlimed) to 6.6. And in each pH plot were four sub-plots with a different amount of mobile phosphorus: potassium. In acid soil (pH 4.1), in spring oilseed rape and in spring barley crops, the dominant weed Spergula arvensis density decreased significantly at a pH of 5.1 or higher. With increasing amount of P2O5:K2O in soil, the abundance of S. arvensis in spring rape and spring barley crops was reduced at all soil pH levels. At pH 5.1, Chenopodium album and Tripleurospermum perforatum were prominent. Elytrigia repens tended to decrease with increased alkalinity and nutrient amount in soil. With reduction of soil acidity from pH 4.1 to 6.6, the total weed infestation consistently declined in all crops. A low amount of P2O5:K2O in soil caused the decline in the abundance of S. arvensis, E. repens and increase in C. album and T. perforatumLietuvos agrarinių ir miškų mokslų centro Vėžaičių filialasVytauto Didžiojo universitetasŽemės ūkio akademij

Long-term manuring effect on weed flora in acid and limed soils

The dominant soils of eastern and western Lithuania are acid. Liming and application of organic fertilizers are therefore the most effective ways to improve properties. Accordingly, two permanent liming and organic manuring trials were initiated in 1949 on an acid soil in the Vezaiciai Branch of the Lithuanian Institute of Agriculture. This study reports the effects of long term manuring on weed flora and topsoil seed content in the sixth rotation of crops in the long-term field experiments (1996–2002). Increasing rates of manure application from 20 to 120 t ha -1 decreases soil seed contents under acidic soil conditions. On the other hand, long-term application of increasing rates of manure did not affect the total number of weeds in limed soil. Number of acidophilic weed species was much lower and plants of Rumex acetosella were not found, but density of nitrophilous weed species increased when long-term application of increasing rates of manure took place in limed soil. Acidophilic weed plants Scleranthus annuus, Spergula arvensis, and Rumex acetosella and their seeds in topsoil dominated in the acid unmanured soilVytauto Didžiojo universitetasŽemės ūkio akademij