Nitrogenase activity of bacterial endophytes in the sandy-loam soil under grass cultivation

A dinitrogen fixation by bacteria living in symbiosis with leguminous plants is a widespread and well-known phenomenon. However, also some free-living bacteria, frequently entering into associations with various plants, reveal capabilities of fixing molecular nitrogen. Such endophytes include bacteria like Acetobacter diazotrophicus and Herbaspirillum seropediceae, discovered in countries of the tropical climate, where they lived in associatins with plants characteristic for this climate as: sugar cane, sorgo and grasses. Until now, however, very little is known about the occurrence of these bacteria in the climate of the temperate zone. Therefore, the objective of this experiment was to find out the influence of the inoculation of Italian ryegrass, Bromus willdenowii and Festulolium braunii with Acetobacter diazotrophicus and Herbaspillirum seropedieae on N2 fixation

The effect of different doses of Soleflor soil improver and mineral fertilizers on botanical composition and yielding of grass-legume sward

The aim of this study was to determine the effect of soil improver Soleflor used in sowing mixture of grass-legumes Country 2006 DSV on botanical composition of the sward, leaf greenness index of white clover and yields. Research on the effects of different doses and frequency of application Soleflor soil conditioner and phosphorus-potassium fertilizers was conducted in 2012–2014 at the Experimental Station of Department of Grassland Natural Landscape Sciences in Brody University of Life Sciences in Poznań. The use of soil conditioner Soleflor increased on the share in the sward of perennial ryegrass and tall fescue. A soil improver influenced on the higher percentage and durability of timothy grass and white clover in the sward. The highest SPAD index values in white clover leaf blades were found after the application along with a standard NPK fertilizer and soil conditioner Soleflor in doses of 400 and 600 kg ha–1

Wplyw wybranych pestycydow na drobnoustroje glebowe

Określono wpływ fungicydowej zaprawy nasiennej Funaben T i herbicydu Pivot 100SL na przeżywalność rdzennych bakterii z rodzaju Rhizobium oraz innych wybranych grup drobnoustrojów glebowych w doświadczeniu modelowym. W przeprowadzonym doświadczeniu glebę inkubowano w słojach w temperaturze 25°C w następujących kombinacjach: 1) gleba - kontrola, 2) gleba z dodatkiem fungicydu, 3) gleba z dodatkiem herbicydu, 4) gleba z dodatkiem fungicydu i herbicydu. W 3, 7, 14, 30 i 60-tym dniu inkubacji określano dla każdej kombinacji, wpływ zastosowanych pestycydów na: Rhizobium, Azotobacter, grzyby, ogólna ilość bakterii i promieniowców. Nie bez wpływu okazały się zastosowane pestycydy dla badanych grup drobnoustrojów glebowych, powodując hamownie lub stymulowanie ich namnażania, szczególnie w pierwszych dniach po zastosowaniu, w dalszych terminach często stymulowały ich rozwój.The effect of fungicide seed dressing Funaben T and herbicide Pivot 100SL on the survival of indigenous population of nodule bacteria and other group of microorganisms was determined. In this investigation soil was incubated at 25°C. We used four combinations in this investigation: 1) soil - control, 2) soil with fungicide, 3) soil with herbicide, 4) soil with fungicide and herbicide. After 3, 7, 14, 30 and 60 days of incubation the number of microorganisms (Rhizobium, Azotobacter, actinomyces, fungi and bacteria) was determined using the dilution plate method and the appropipriate agar media (in three replications). The number of colonies was calculated for 1 g of dry soil (cfu·g⁻¹ DM). The obtained results showed that the crop protection preparations applied in the experiment reduced the number of indigenous population of nodule bacteria, Azotobacter and soil bacteria in the first days after application, while later they were found to stimulate their multiplication

The influence of a soil bioconditioner on the microbiological state and enzymatic activity of the soil under Lolium perenne plantation

The influence of the Soleflor soil bioconditioner on the soil pH, its bioactivity (the population of selected groups of soil microorganisms, the enzymatic activity of the soil), the plant vigour expressed with the SPAD index and the perennial ryegrass sward yield were investigated in a two-year field experiment in a perennial ryegrass plantation. The influence of Soleflor on the soil pH and the population of microorganisms proved to be minimal, ambiguous and statistically insignificant. The preparation was observed to have minimal influence on the increase in the enzymatic activity of soil. A noticeable reaction to fertilisation with the Soleflor preparation was observed in the plants which in both treatments with the Soleflor showed significantly greater vigour and yield than in the control samples

Wieloletnie oddziaływanie systemów uprawy roli na wybrane właściwości gleby i plonowanie grochu (Pisum sativum L.)

Compared with ploughing tillage, no-tillage systems through their diversified effect on soil, modify its properties, and consequently conditions of plants’ growth and development. The aim of the study was evaluation of the long-term effect of various tillage systems on the pea yield and some soil properties. The experimental design included 5 tillage variants: 1 – conventional tillage applied annually: skimming + harrowing, sow ploughing to a depth of 25 cm, cultivator unit (cultivator with a string roller), 2 – reduced tillage applied annually (stubble cultivator), 3 – direct sowing into stubble applied annually, 4 – direct sowing applied alternately with reduced tillage, 5 – direct sowing interrupted after 2 years with an annual reduced tillage. The highest pea yields were obtained after reduced tillage, while application of conventional tillage and direct sowing under this plant resulted in a decrease in the grain yield by 7.5 and 11.0%, respectively. Differences in the grain yields in pea between tillage systems resulted mainly from a different plant density per 1 m² before harvest. No-tillage systems did not decrease protein content in pea grains compared with pea cultivation in a ploughing system. No beneficial effect was observed of the applied direct sowing interrupted with reduced tillage on the yield of pea. Long-term application of reduced tillage and direct sowing was favorable for increasing moisture and bulk density of the soil as well as for decreasing capillary water capacity. Moreover, it stimulated activity of soil enzymes to a depth of 10 cm.Bezorkowe systemy uprawy roli, poprzez odmienne oddziaływanie na glebę w porównaniu do uprawy płużnej, modyfikują jej właściwości, a w konsekwencji warunki wzrostu i rozwoju roślin. Celem badań była ocena wieloletniego oddziaływania różnych systemów uprawy roli na plonowanie grochu oraz wybrane właściwości gleby. Schemat doświadczenia obejmował 5 wariantów uprawy roli: 1 – uprawa tradycyjna stosowana corocznie: podorywka + bronowanie, orka siewna na głębokość 25 cm, agregat uprawowy (kultywator z wałem strunowym), 2 – uprawa uproszczona stosowana corocznie (kultywator ścierniskowy), 3 – siew bezpośredni w ściernisko stosowany corocznie, 4 – siew bezpośredni stosowany przemiennie z uprawą uproszczoną, 5 – siew bezpośredni przerywany po 2 latach jednoroczną uprawą uproszczoną. Największe plony grochu uzyskano po uproszczonej uprawie roli, natomiast zastosowanie uprawy tradycyjnej oraz siewu bezpośredniego pod tę roślinę skutkowało obniżeniem plonu nasion, odpowiednio o 7,5 i 11,0%. Różnice w plonach nasion grochu pomiędzy systemami uprawy roli wynikały głównie z odmiennej obsady roślin na 1 m² przed zbiorem. Sposoby uprawy bezorkowej nie obniżały zawartości białka w nasionach grochu w odniesieniu do jego uprawy w systemie płużnym. Nie odnotowano korzystnego oddziaływania na plonowanie grochu zastosowanego siewu bezpośredniego przerywanego uprawą powierzchniową. Wieloletnie stosowanie uprawy uproszczonej i siewu bezpośredniego sprzyjało zwiększaniu wilgotności i gęstości objętościowej gleby oraz zmniejszaniu kapilarnej pojemności wodnej, a ponadto stymulowało aktywność enzymów w glebie do głębokości 10 cm

The effect of soil improvers used in the cultivation of Medicago sativa on selected chemical and biological properties of soil

The objective of this study was to determine the effect of selected calcium-based soil improvers applied to field-grown alfalfa (Fraver) on the some chemical and biological properties of soil. The research revealed that the application of the improvers noticeably increased the pH of soil and the content of magnesium. The influence of the soil improvers on the microbial and enzymatic properties of soil was equivocal. However, it can be concluded that this speciments increased the number of total bacteria and oligotrophs and the enzymatic activity of soil