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This research evaluates the influence of mineral fertilizers on structural components and the formation of productivity of various Lens culinaris varieties on dark chestnut soils of the dry-steppe zone of Northern Kazakhstan. The application of nitrogen and phosphorus fertilizers in the doses up to P120 (P2O5 25-30 ppm) and N30-60 against the background of P90 (N-NO3 12-17 ppm) with a phosphorus content of 11-15 ppm and nitrogen 7-9 ppm at the control plots contributed to the formation of the highest yield of lentils' varieties "Krapinka", "Vekhovskaya", and "Viceroy" up to 1.44 t/ha, 1.89 t/ha, and 1.92 t/ha respectively. The increase in yield is due to an increase in the number of formed beans (up to 18.2-26.0 pcs) and the weight of seeds per plant (up to 1.04-1.23 g), which is confirmed by correlation analyses (R = 0.91; R = 0.96). The yield relationship with the number of branches is medium (R = 0.72) and with a mass of 1000 seeds from medium to high (strong) (R = 0.70-0.87). The mass of 1000 seeds is the most stable indicator of variation among the structural components of yield, regardless of the background of mineral nutrition. [ABSTRACT FROM AUTHOR]

Chemical insecticides are intensively used in agriculture which cause negative effects on environmental sustainability by increasing pest tolerance and continuous action on local fauna. In contrast to chemical insecticides, biological insecticides target specific pests, minimizing their impact on the surrounding environment. However, most of the natural insecticides available in the market are expensive for farmers in the Central Asian region. This study is the first evidence of the effectiveness of local entomopathogenic nematodes (EPN) from the arid zone of northern Kazakhstan that can be used as an alternative to export EPN products. The laboratory experiment is conducted with two local and two commercial Steinernema feltiae and Steinernema carpocapsae, which are applied to larvae of Tenebrionidae. The experiment design is randomized with four doses of EPN (100, 200, 300, and 400 IJ/cm2) and a control (without EPN). According to the experiment results, one out of two local EPNs (AF29 at dose 100 IJ/cm2) caused a high mortality rate (67%) among larvae. This finding confirms that local EPNs can compete with commercial EPNs and potentially be used as insecticidal agents. [ABSTRACT FROM AUTHOR]

Adaptive multi-paddock (AMP) grazing is a form of rotational grazing in which small paddocks are grazed with high densities of livestock for short periods, with long recovery periods prior to regrazing. We compared the fluxes of greenhouse gases (GHGs), including carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), from soils of AMP-grazed grasslands to paired neighboring non-AMP-grazed grasslands across a climatic gradient in Alberta, Canada. We further tested GHG responses to changes in temperature (5 °C vs. 25 °C) and moisture levels (permanent wilting point (PWP), 40% of field capacity (0.4FC), or field capacity (FC)) in a 102-day laboratory incubation experiment. Extracellular enzyme activities (EEA), microbial biomass C (MBC) and N (MBN), and available-N were also measured on days 1, 13, and 102 of the incubation to evaluate biological associations with GHGs. The 102-day cumulative fluxes of CO2, N2O, and CH4 were affected by both temperature and moisture content (p < 0.001). While cumulative fluxes of N2O were independent of the grazing system, CH4 uptake was 1.5 times greater in soils from AMP-grazed than non-AMP-grazed grasslands (p < 0.001). There was an interaction of the grazing system by temperature (p < 0.05) on CO2 flux, with AMP soils emitting 17% more CO2 than non-AMP soils at 5 °C, but 18% less at 25 °C. The temperature sensitivity (Q10) of CO2 fluxes increased with soil moisture level (i.e., PWP < 0.4FC ≤ FC). Structural equation modelling indicated that the grazing system had no direct effect on CO2 or N2O fluxes, but had an effect on CH4 fluxes on days 1 and 13, indicating that CH4 uptake increased in association with AMP grazing. Increasing soil moisture level increased fluxes of GHGs—directly and indirectly—by influencing EEAs. Irrespective of the grazing system, the MBC was an indirect driver of CO2 emissions and CH4 uptake through its effects on soil EEAs. The relationships of N-acetyl-β glucosaminidase and β-glucosidase to N2O fluxes were subtle on day 1, and independent thereafter. AMP grazing indirectly affected N2O fluxes by influencing N-acetyl-β glucosaminidase on day 13. We conclude that AMP grazing has the potential to mitigate the impact of a warmer soil on GHG emissions by consuming more CH4 compared to non-AMP grazing in northern temperate grasslands, presumably by altering biogeochemical properties and processes. [ABSTRACT FROM AUTHOR]

Grasslands are used extensively for grazing livestock, and variation in grazing management may affect the soil microbial community and ecosystem functions, such as nutrient cycling, in grasslands. In particular, adaptive multi-paddock (hereafter 'multi-paddock') grazing is considered a regenerative grazing management practice that can improve the sustainability of grasslands. However, little is known about how multi-paddock grazing affects the soil microbial community, which plays an importance role in global biogeochemical cycling. In this study, grassland soils were collected from 15 ranch pairs located across the Canadian prairie, where, in each pair, one ranch practiced multi-paddock grazing while the other practiced conventional grazing (varying from continuous to slow to fast rotational grazing). We used soil phospholipid fatty acid (PLFA) profiles to quantify microbial functional groups, and measured microbial biomass C and soil properties. Our data show that microbial PLFA abundances and microbial biomass C was not different between the two grazing systems. However, multi-paddock grazing resulted in lower ratios of microbial biomass C: N (MBC:MBN), fungi: bacteria (F:B) and Gram-positive: Gram-negative bacteria in grassland soils compared to conventional grazing. Further investigation of specific management metrics revealed that MBC:MBN and F:B ratios were most affected by cattle stocking rate and stocking density, respectively. Thus, there is potential to affect soil function by altering the composition of soil microbial communities through multi-paddock grazing. • Adaptive multi-paddock grazing (AMP) altered soil microbial PLFA composition. • Increased cattle stocking rates reduced microbial biomass C:N. • Increased cattle stocking density decreased fungi:bacteria ratio. • AMP reduced MBC:MBN, F:B and Gram-positive:Gram-negative ratios. • Microbial changes indicate potential effects on carbon cycling and storage. [ABSTRACT FROM AUTHOR]