New Pellet Feeds for Rabbits with a High Content of Nutrients and With the Addition of Dietary Supplements

This research presented the pellet feed production line. Three pellet feed formulasfor young stock rabbits (28-135 days old) were developed with the addition of experimental dietary supplements grouped into the following protein green complexes (PGC):PGC-92-1including thе following supplements- dried herbal pulp from red clover, herbal alfalfa meal, and Sporotherminprobiotic; PGC-92-2 including the following supplements - protein feed concentrate from wheat stillage filtrate (syrup), herbal alfalfa meal, and Sporothermin probiotic; PGC-92-3 including the following supplements – PGC from red clover, herbal alfalfa meal,andSporothermin probiotic. These were compared with feed formulated without dietary supplements (PGC-92 (Control)). The nutritional value of the concentrate feeds met the requirements assigned for this group of animals. The storage of the formulatedconcentrate feeds took place in industrial conditions (the floor store) in paper bags of 30 kg per group at the temperature of 18-20 ∘C and the relative humidity of 65-70%. Due to itsmoisture content exceeding the standard requirements, the check concentrate feed (Control) revealed a higher content of fungal and bacterial microflora. The fat acidityvalue and the total acidity increased, which indicated the instability of this batch of concentrate feed during storage. The experimental batches of concentrate feed had a stablequality and retained good quality throughout the testing period. The testing of the effects of the studied complexes in fattening young stock rabbits was carried out on the premises of the Lipetsk Rabbit LLC industrial complex with 2000 rabbits. The use ofall-in-onepellet feedsformulated with the addition ofdietary supplements made it possible to increase the slaughter yield by 3.62%, 4.45% and 3.96%, while reducing feed intake per 1 kg of slaughter mass by 0.72 ECU, 0.38 ECU and 0.88 ECU. There was an increase in profit of 17725.25rubles, 16114.38 rubles and 14168.55 rubles, and an increase in the level of profitability by 45.93%, 41.26% and 31.24%, which resulted from a highersafety andgrowth performance of the raised rabbits. Keywords: concentrate feeds, pellet feeds, dietary supplements, protein green complex, feed for rabbits, growth performance

Chromosome-scale assembly of the highly heterozygous genome of red clover (Trifolium pratense L.), an allogamous forage crop species

Red clover (Trifolium pratense L.) is used as a forage crop due to a variety of favorable traits relative to other crops. Improved varieties have been developed through conventional breeding approaches, but progress could be accelerated and gene discovery facilitated using modern genomic methods. Existing short-read based genome assemblies of the ~420 Megabase (Mb) genome are fragmented into >135,000 contigs with numerous errors in order and orientation within scaffolds, likely due to the biology of the plant which displays gametophytic self-incompatibility resulting in inherent high heterozygosity. A high-quality long-read based assembly of red clover is presented that reduces the number of contigs by more than 500-fold, improves the per-base quality, and increases the contig N50 statistic by three orders of magnitude. The 413.5 Mb assembly is nearly 20% longer than the 350 Mb short read assembly, closer to the predicted genome size. Quality measures are presented and full-length isoform sequence of RNA transcripts reported for use in assessing accuracy and for future annotation of the genome. The assembly accurately represents the seven main linkage groups present in the genome of an allogamous (outcrossing), highly heterozygous plant species.

Main soil nutrients dynamics in sod-dressing intercropped orchard

The study aimed to estimate seasonal dynamics of soil nitrogen, phosphorus and potassium under the influence of sod grasses in a sod-dressing intercropped orchard. The trial was conducted in a Welsey apple 1987-year orchard. Trees were planted at 8×6 m, cultivar seedlings used as rootstock. Red clover and meadow timothy in variant shares were used for interrow sodding. The cereal—legume intercropping was done in 2015, preceded by a 180 kg/ha active substance phosphorus-potassium dressing in reserve. Nitrogen was applied annually prior to growing season at 34.4 kg/ha active substance. Grass biomass in first hay cutting was the highest and comprised 45.3-49.9 % total mass. A total four cuttings dry mass was 3.36-7.10 t/ha depending on scheme. The maximum biomass was registered for the schemes with red clover and meadow timothy at ratios 1:1 and 7:3 (6.52 and 7.10 t/ha). In the growing period, grass depleted soil for 111.1—219.9 kg/ha nitrogen, 21.5-42.7 kg/ha phosphorus and 209.3—380.8 kg/ha potassium. Such consumptions suggest a serious competition for soil nutrients between grass vegetation and fruit trees. The available phosphorus and potassium content was independent of interrow dressing schemes. Inter-scheme differences did not exceed experimental bias due to presowing phosphorus and potassium application in reserve before trial. By first cutting, the nitrate nitrogen soil content in sodding schemes was 1.5-2-fold less vs. bare fallow, i.e. more nitrogen is used by vegetating grass, and its available forms recover slower than being consumed.

Modified materials based on layered minerals as ameliorants for the remediation of podzol in the industrial barren

Layered silicates, such as serpentine and vermiculite, have properties that make it possible to use materials based on them as components of environmental technologies. The possibility of soil remediation in industrially contaminated area, formed due to the long-term exposure to emissions from copper-nickel production (Monchegorsk, Murmansk region), was studied. Two materials were used as ameliorants in our study: expanded vermiculite and granular serpentine sorbent, a waste after using the purification technology of highly concentrated solutions from metals. These materials have a high sorption activity to several metals, a high specific surface area, the ability to retain moisture, and are available in quantities sufficient to work on the remediation of large areas. A study of the physicochemical properties of industrially polluted soil and ameliorants, direct phytotoxicity testing of podzol and its mixtures with expanded vermiculite and the serpentine sorbent (test plants - common oat Avna satva L. and red clover Trifolium pratnse L.) were carried out. The study results showed that the proposed materials were effective additives for increasing the pH of acidic soil, sorption and precipitation of Al and potentially toxic metals - Cu, Ni, Pb, Fe, and improving the soil hydrophysical and agrochemical characteristics. A positive response of test plants to the introduction of ameliorants into industrially contaminated soil was noted.

Seed Production of Red Clover (Trifolium pratense L.) under Danish Field Conditions

High and stable seed yield is critical for red clover (Trifolium pratense L.) seed production and the commercial exploitation of the crop. A three-year experiment was conducted from 2013 to 2015 under Danish field conditions to explore the influence of precipitation during peak flowering on the seed yield of three red clover cultivars. We investigated the flowering duration and intensity based on a visual scale assessment, seed yield, and thousand seed weight in all three experimental years. In 2014 and 2015 we measured the seed yield components of floret number per flower head, seed number per flower head, and seed set. During the experimental period, high seed yields of more than 1000 kg ha−1 were obtained for the diploid cultivars ‘Rajah’ and ‘Suez’. Although a relatively high seed yield of 500 kg ha−1 was obtained in the tetraploid cultivar ‘Amos’, this was only around half of the seed yield and seed set of the diploid cultivars. Precipitation during peak flowering positively influenced the seed yield and thousand seed weight for the three cultivars. We conclude that observations of flowering phenology are required to determine the impact of environmental conditions on seed yield in red clover cultivars. Further, adequate water supply during peak flowering is important to obtain the high seed yield of red clover.

Effects of Nitrogen Rates on the Productivity and Nutritive Value of Forage Grass Grown under Extreme Climatic Conditions

This vegetative experiment was carried out at the greenhouse of Vytautas Magnus University Agriculture Academy Open Access Joint Research Centre of Agriculture and Forestry (Lithuania) in 2020–2021. The aim of these studies was to determine the effect of different nitrogen rates on the productivity and nutritional quality of forage grasses (a mixture of red clover and timothy) under the most common extremes of climate change, i.e., soil moisture deficiency and surplus. Under drought and waterlogging stresses, fertilization of the red clover and timothy mixture with high N rates was ineffective. The clover and timothy mixture recovery after drought took 21 days. The aboveground dry biomass of the clover and timothy mixture grown under drought conditions was significantly lower by 36.3 to 47.2% compared to that formed under optimum soil moisture and waterlogging conditions. The root biomass of forage grass mixtures was lowest under drought conditions when fertilized at the highest N rate (N25+120). The aboveground biomass of clover grown under different soil moisture conditions depended on the number of plants (r2 = 0.78, p < 0.01) and assimilating leaf area (r2 = 0.83, p < 0.01), and that of timothy on the number of vegetative tillers (r2 = 0.46, p < 0.05). Under drought simulation conditions, increasing the N rate increased the crude protein and crude fibre contents in the aboveground biomass of the clover and timothy mixture, while the crude ash content decreased.

GBS and a newly developed mRNA-GBS approach to link population genetic and transcriptome analyses reveal pattern differences between sites and treatments in red clover (Trifolium pratense L.)

The important worldwide forage crop red clover (Trifolium pratense L.) is widely cultivated as cattle feed and for soil improvement. Wild populations and landraces have great natural diversity that could be used to improve cultivated red clover. However, to date, there is still insufficient knowledge about the natural genetic and phenotypic diversity of the species. Here, we developed a low-cost transcriptome analysis (mRNA-GBS) with reduced complexity and compared the results with population genetic (GBS) and previously published mRNA-Seq data, to assess whether analysis of intraspecific variation within and between populations and transcriptome responses is possible simultaneously. The mRNA-GBS approach was successful. SNP analyses from the mRNA-GBS approach revealed comparable patterns to the GBS results, but it was not possible to link transcriptome analyses with reduced complexity and sequencing depth to previously published greenhouse and field expression studies. The use of short sequences upstream of the poly(A) tail of mRNA to reduce complexity are promising approaches that combine population genetics and expression profiling to analyze many individuals with trait differences simultaneously and cost-effectively, even in non-model species. Our mRNA-GBS approach revealed too many additional short mRNA sequences, hampering sequence alignment depth and SNP recovery. Optimizations are being discussed. Nevertheless, our study design across different regions in Germany was also challenging as the use of differential expression analyses with reduced complexity, in which mRNA is fragmented at specific sites rather than randomly, is most likely counteracted under natural conditions by highly complex plant reactions at low sequencing depth.

Effects of the noncoding subgenomic RNA of red clover necrotic mosaic virus in virus infection

In recent years, a new class of viral noncoding subgenomic (ncsg)RNA has been identified. This RNA is generated as a stable degradation product via an exoribonuclease-resistant (xr) RNA structure, which blocks the progression of 5’→3’ exoribonuclease on viral RNAs in infected cells. Here, we assess the effects of the ncsgRNA of red clover necrotic mosaic virus (RCNMV), called SR1f, in infected plants. We demonstrate: (i) absence of SR1f reduces symptoms and decreases viral RNA accumulation in Nicotiana benthamiana and Arabidopsis thaliana plants; (ii) SR1f has an essential function other than suppression of RNA silencing; and (iii) the cytoplasmic exoribonuclease involved in mRNA turnover, XRN4, is not required for SR1f production or virus infection. A comparative transcriptomic analysis in N. benthamiana infected with wildtype RCNMV or an SR1f-deficient mutant RCNMV revealed that wt RCNMV infection, which produces SR1f and much higher levels of virus, has a greater and more significant impact on cellular gene expression than the SR1f-deficient mutant. Upregulated pathways include plant hormone signaling, plant-pathogen interaction, MAPK signaling, and several metabolic pathways, while photosynthesis-related genes were downregulated. We compare this to host genes known to participate in infection by other tombusvirids. Viral reads revealed a 10 to 100-fold ratio of positive to negative strand, and the abundance of reads of both strands mapping to the 3’ region of RCNMV RNA1 support the premature mechanism of synthesis for the coding sgRNA. These results provide a framework for future studies of the interactions and functions of noncoding RNAs of plant viruses. IMPORTANCE Knowledge of how RNA viruses manipulate host and viral gene expression is crucial to our understanding of infection and disease. Unlike viral protein-host interactions, little is known about the control of gene expression by viral RNA. Here we begin to address this question by investigating the noncoding subgenomic (ncsg)RNA of red clover necrotic mosaic virus (RCNMV), called SR1f. Similar exoribonuclease-resistant RNAs of flaviviruses are well-studied, but the roles of plant viral ncsgRNAs, and how they arise, are poorly understood. Surprisingly, we find the likely exonuclease candidate, XRN4, is not required to generate SR1f, and we assess the effects of SR1f on virus accumulation and symptom development. Finally, we compare the effects of infection by wildtype RCNMV vs an SR1f-deficient mutant on host gene expression in Nicotiana benthamiana , which reveals that ncsgRNAs such as SR1f are key players in virus-host interactions to facilitate productive infection.