Response of common bean to Rhizobium reinoculation in topdressing

ABSTRACT The response capacity of the bean to fix atmospheric nitrogen is questionable, mainly due to its inability to supply all the nitrogen in the flowering and grain filling phases when the crop needs it most. Thus, a new application of inoculant can keep the population of rhizobia in the soil at adequate levels, meeting all the nitrogen demands of the plant. This study aimed to investigate the nodulation capacity and the production of beans submitted to doses and reinoculation of Rhizobium in topdressing under field conditions in two growth stages. For this, an experiment was conducted using a randomized block design with four replicates in a 4 × 2 + 2 factorial scheme. The treatments consisted of the application of four doses of liquid inoculant containing Rhizobium tropici (SEMIA 4088), in the concentration 2 × 109 CFU g-1, in topdressing (0, 100, 200 and 400 mL ha-1), in two development stages (V4 and R5) of plants, and two additional treatments (inoculation via seed at a dose of 100 g of the product per 50 kg of seeds and mineral nitrogen fertilization at a dose of 16 kg ha-1 applied at sowing and 60 kg ha-1 in topdressing, divided into two stages, with half being applied at the stage V3 and the other half in V4 stage).The inoculant application increased the nodulation rates of bean cultivar BRS Cometa and the dry biomass produced by plants, using doses of 232 and 221 mL ha-1, respectively. The dose of 257mL ha-1 of the liquid inoculant applied in topdressing at the V4 stage, and the inoculation via seed provide greater common bean yield without supplementing mineral nitrogen.

The Effect of Mineral N Fertilization and Bradyrhizobium japonicum Seed Inoculation on Productivity of Soybean (Glycine max (L.) Merrill)

Soybean yields can be considerably improved by inoculation with selected Bradyrhizobium japonicum strains and fertilization. The aim of this study was to assess the productivity of two soybean cultivars depending on the applied N mineral fertilizers and seed inoculation with B. japonicum. The study showed that on average, for both cultivars, the soybean yield was most favorably affected by the combined use of inoculation and nitrogen fertilization (increase in seed yield by 42%, protein yield by about 28%). The application of mineral nitrogen at the dose of 30 or 60 kg·ha−1 allowed the increase in the seed yield by about 17% and protein content by about 14% compared to the control. Inoculation of soybean seeds with B. japonicum increased the yield of soybeans by about 20%, proteins by about 10% compared to the control, and inoculation of Hi®Stick Soy favored a better yield than Nitragina. Inoculation of seeds with Nitragina or Hi®Stick Soy and fertilization with mineral nitrogen increased the content of protein and fiber in seeds of both soybean cultivars, as well as reduced the amount of ash and fat. The seeds of cv. Aldana had a higher amount of protein and ash than cv. Annushka, but a similar amount of fat and fiber.

Quantification and comparison of ecosystem services of grasslands versus another fodder crop (maize) based on mineral nitrogen content in the 60–90 cm soil layer

Grasslands provide many ecosystem services. Apart from being a source of fodder for animals, grasslands regulate water and soil quality by reducing nitrogen emissions to the environment. The aim of the study was to determine the biophysical and monetary value of ecosystem services of grassland based on the “mineral nitrogen content in the soil layer 60–90 cm” indicator depending on the method of use and the type of soil, against the cultivation of maize for green fodder. The study area encompassed three provinces, different in terms of soil use, livestock population and intensity of grassland use. The investigation indicated that the value of ecosystem services provided by grasslands varied spatially and depended on the type of use and type of soil. In mineral soils, the lowest levels of this index were recorded from sites used for pasturing, while the highest levels were found under maize crops. In organic soils (without maize crops), the smallest losses of Nmin were observed in meadows while the highest losses were in pastures. Nmin losses in organic soils were higher than in mineral soils. The losses observed were highest in Opolskie Province, followed by Podlaskie Province, with the lowest losses in Lubelskie Province.

Communities with Galega orientalis Lam. in Kursk Region

. Plant communities dominated by the invasive species Galega orientalis, common in natural and anthropogenic habitats, have been identified in Kursk Region. On anthropogenic ecotopes (wastelands, roadsides), phytocoenoses of the ass. Galigetum orientalis are formed as a result of introduction of Galega orientalis into communities of the order Agropyretalia intermedio–repentis (class Artemisietea vulgaris). In natural habitats, Galega orientalis spreads in mesophylous meadow communities (order Arrhenatheretalia, class Molinio-Arrhenatheretea), while derivative communities Galega orientalis [Arrhenatheretalia] are formed. Galega orientalis is unevenly present in derivative communities, forming separate loci, as a result, its cover is less intensive than in anthropogenic communities. It may be due to a more intensive distribution of this species in disturbed habitats. Comparison of ranges of values of environmental factors showed that derivative communities are formed in wetter habitats. Phytocoenoses of the association are characterized by wider variation in values of acidity and richness of soils in mineral nitrogen.

Features of the species composition and structure of fish communities in small anthropogenic reservoirs with different content of dissolved mineral nitrogen

In 22 small anthropogenic reservoirs with an area of 0.4 to 62 ha located in the territory of the Udmurt Republic, individuals of different fish species were captured and water samples were taken in late spring for analysis of NO3–, NO2– and NH4+ content. In many reservoirs, concentrations of ammonium exceed the maximum permissible according to the fishing standards for water quality, and in some this is also the case with nitrites. Ponds with zooplanktophages (bleak Alburnus alburnus (L.) and belica Leucaspius delineates (Heckel)) present in fish communities were statistically significantly different in the increased content of total dissolved mineral nitrogen from reservoirs where these two fish species were not registered. In perch and roach reservoirs, the numerical proportion of river perch Perca fluviatilis was negatively and statistically significantly related to the level of their contamination with nitrogen ionic forms.