Sudangrass Research Articles

CcNAC6 Acts as a Positive Regulator of Secondary Cell Wall Synthesis in Sudan Grass (Sorghum sudanense S.).

The degree of forage lignification is a key factor affecting its digestibility by ruminants such as cattle and sheep. Sudan grass (Sorghum sudanense S.) is a high-quality sorghum forage, and its lignocellulose is mostly stored in the secondary cell wall. However, the secondary cell wall synthesis mechanism of Sudan grass has not yet been studied in depth. To further study the secondary cell wall synthesis mechanism of Sudan grass using established transcriptome data, this study found that CcNAC6, a homologous gene of Arabidopsis AtSND2, is related to the secondary cell wall synthesis of Sudan grass. Accordingly, we constructed a CcNAC6-overexpressing line of Arabidopsis to investigate the function of the CcNAC6 gene in secondary cell wall synthesis. The results showed that the overexpression of the CcNAC6 gene could significantly increase the lignin content of Arabidopsis. Based on subcellular localization analysis, CcNAC6 is found in the nucleus. In addition, yeast two-hybridization screening showed that CcCP1, associated with secondary cell wall synthesis, can interact with CcNAC6. Therefore, the above results indicate that CcNAC6 has a positive regulatory effect on the secondary cell wall synthesis of Sudan grass, and it is speculated that CcNAC6 may be the main regulator of the secondary cell wall synthesis of Sudan grass through its interaction with another regulatory protein, CcCP1. This study provides a theoretical basis and new genetic resources for the creation of new Sudan grass germplasm with a low lignin content.

Effects of cover crops and nitrogen fertilization on soil physical properties, carbon and nitrogen fractions, and winter wheat yield in the Chinese loess plateau: A 4-year field experiment

Context or problemLone-term application of chemical fertilizers in farmland ensure adequate or profitable crop yields but may damage soil structure. Cover crops (CCs) have great potentials to improve soil quality and promote sustainable crop production. However, the combined impacts of CCs with nitrogen fertilization on soil quality and crop yields are not clear. Objective or research questionWe aimed to examine the effects of CCs combined with N fertilization rates on soil physical properties, C and N fractions in both bulk soils and aggregates, and crop yields, and to find the best management practice that improve both soil quality and crop yields synthetically. MethodsA 4-year summer CCs - winter wheat field experiment was conducted in the Loess Plateau of China. CCs with different species and combinations (CC) were soybean (SB), sudan grass (SG), a mixture of both (SS), and no cover crop (CK) and N fertilizer (NR) were applied to winter wheat at rates of 0 (N0), 60 (N60), and 120 (N120) kg N ha−1. Soil physical properties and C and N fractions in both bulk soils and aggregates were evaluated at 0–10, 10–20, and 20–40 cm soil depths. ResultsSoil total porosity (TP), saturated water content (SWC), capillary water capacity (CWC), and C and N fractions decreased while bulk density (BD) increased with the increase of soil depth. The CC, NR, and their interaction (CC×NR) had significant effects on soil BD, aggregate size distribution and stability (MWD), and C and N fractions and only CC and CC×NR had significant effects on other physical properties. The incorporation of CCs significantly increased the proportions of > 5 mm aggregates and C and N fractions in both bulk soils and aggregates, especially in 0–10 and 10–20 cm. And SB and SS improved soil other physical properties more than SG, especially in 0–10 cm, which decreased BD by 13.2% and 12.6% while increased TP by 6.5% and 8.3%, SWC by 14.3% and 15.3%, CWC by 13.9% and 14.2%, MWD by 16.6% and 14.4%, respectively, compared to CK. Additionally, soil physical properties improved more with N60 while the C and N fractions in both bulk soils and aggregates increased more with N120. However, BD increased by 2.6% and 3.3% in N60 and N120 than N0, respectively. The correlations between the proportion of macro-aggregates and soil C and N fractions at 0–10 and 10–20 cm indicated the positive effects of CCs on improving soil structure and fertility simultaneously. Aggregated-associated C and N fractions decreased firstly and then increased with the reduced aggregate sizes, and were higher in micro-aggregates than in other size classes. N60-SB increased wheat yields by 98.7% compared with N0-CK. ConclusionsOverall, the incorporation of soybean residue was the best management practice for winter wheat yield and soil fertility under the reduced N fertilization. Implications or significanceThe selection of CCs species should depend on farmland managements, and the appropriate CCs with N fertilizer rates would target the improvements in soil quality, the sequestration of soil organic carbon, and crop yields synergistically.

Influence of EMR–Phosphogypsum–Biochar Mixtures on Sudan Grass: Growth Dynamics and Heavy Metal Immobilization

This study investigates the growth dynamics and heavy metal immobilization in Sudan grass cultivated on substrates composed of electrolytic manganese residue (EMR), phosphogypsum, and chili straw biochar. Pot experiments revealed that a substrate with phosphogypsum constituting 75% of the mix hinders Sudan grass seed germination. Compared with sole EMR utilization, the composite substrates notably enhanced plant growth, evidenced by increases in plant height and fresh weight. The integration of these substrates led to a significant elevation in total chlorophyll content (up to 54.39%) and a reduction in malondialdehyde (MDA) levels (up to 21.66%), indicating improved photosynthetic activity and lower oxidative stress. The addition of biochar reduced the content of Zn, Cd, and Mn in the roots of Sudan grass by up to 25.92%, 20.00%, and 43.17%, respectively; and reduced the content of Pb, Mn, and Cr in the shoot by up to 33.72%, 17.53%, and 26.32%, respectively. Fuzzy membership function analysis identified the optimal substrate composition as 75% EMR and 25% phosphogypsum, with 5% chili straw biochar, based on overall performance metrics. This study adopts the concept of “to treat waste with waste”. The approach is to fully consider the fertility characteristics of EMR, phosphogypsum, and biochar, underscoring the potential for utilizing waste-derived materials in cultivating Sudan grass and offering a sustainable approach to plant growth and heavy metal management.

The effect of the moisture availability rate on the productivity and nutritional value of sorghum crops

Productivity reduced by drought is quite common. There can be up to 60.0% of the harvest losses. This is especially true for forage crops. The purpose of the current work was to identify the dependence of productivity and quality of green mass of sorghum crops on moisture availability during a vegetation period of plants. Sudan grass variety Alice, sugar sorghum variety Yuzhnoye, and sorghum-sudangrass hybrid variety Gustolistny were used as research objects. The study was carried out in the Rostov region. The soil of the experimental plot was ordinary carbonate black earth (chernozem). In order to study the variability of productivity and nutritional qualities, the years with the HTC level from 0.34 to 0.88 with an interval of 0.8–1.2 (2018–2022) were taken into account. The trials were conducted according to the methodology of the State Variety Testing. When the HTC increased from 0.34 to 0.88, there was a tendency to improve green mass productivity by 23.3–35.0% and decrease the protein percentage by 41.80–55.54%. A negative relationship between the amount of crude protein and the HTC value was revealed (r = –0.78... –0.92). The digestible protein yield decreased by 22.22–31.03% with increasing moisture content. The largest mean value was identified for the sorghum-sudangrass hybrid with 0.70 t/ha and the sweet sorghum variety with 0.71 t/ha. The variation coefficient of fiber content was 2.16–5.42%, which indicated weak variability of the trait over the years, and, consequently, a weak dependence on the moisture availability rate, which was confirmed by the correlation analysis (r = –0.03...0.32). The largest value of the metabolic energy was found in the sorghum-sudangrass hybrid (10.42–10.80 mJ/kg). At the same time, there was no dependence of this indicator, as well as the amount of feed units, on the moisture availability rate. The highest amount of digestible protein per feed unit was identified in sweet sorghum (83.4 g). A tendency to decrease this indicator by 22.6–42.5% was found as the HTC level increased (r = –0.69...–0.90).

Assessment of nutrient content in grain, hydroponic and conventional fodder with focus on maize, wheat and Sudan grass

Assessment of nutrient content in grain, hydroponic and conventional fodder with focus on maize, wheat and Sudan grass

Influence of conditioner and straw on the herbaceous plant-based phytoremediation copper tailings: a field trial at Liujiagou tailings pond, China.

A field trial was performed to carry out an enhanced phytoremediation technique for multi-metal contaminated copper tailings by Sudan grass (Sorghum Sudanese), ryegrass (Lolium perenne L.), and Bermuda grass (Cynodon dactylon), using conditioner (TH-LZ01) and straw combination into composite amendments as soil amendments, aimed to obtain the maximum of phytoremediation effect. The results showed that compared with untreated herbaceous plants, the application of conditioner and straw planted with herbaceous plants reduced the pH and conductivity and increased the organic matter and water content of the copper tailings to different degrees. With the addition of conditioner and straw, the DTPA-Cd, DTPA-Cu, DTPA-Pb, and DTPA-Zn contents in the copper tailings showed a decreasing trend compared with the untreated group. The herbaceous plants were promoted to reduce the percentage contents of acid soluble fractions Cd, Cu, Pb, and Zn and to increase the percentage contents of reducible, oxidizable, and residual fractions heavy metals (Cd, Cu, Pb, and Zn) in the copper tailings to different degrees. The contents of Cd, Cu, Pb, and Zn in the underground part of herbaceous plants were higher than those in the aboveground part, and the contents of Cd, Cu, Pb, and Zn in the aboveground part and underground part decreased after adding conditioner and straw, which indicated that the conditioner and straw inhibited the transport of heavy metals in the plant. Furthermore, the principal component analysis showed that the application of conditioner and straw with planting ryegrass had more potential for improving the physicochemical properties of copper tailings and reducing heavy metal toxicity, followed by Bermuda grass and Sudan grass.

Use of hybridization to develop new sorghum varieties and hybrids

Hybridization is the main method for developing new breeding material, obtaining genetic variability, and combining desired traits. The purpose of the current work is to characterize new promising varieties and hybrids of sweet and grass sorghum developed by the “ARC “Donskoy” because of hybridization on a sterile and fertile basis. The study was conducted on the breeding field of the FSBSI “ARC “Donskoy”, Zernograd, Rostov region in 2021–2023. The zone is characterized by ordinary carbonate chernozem (3.2 % of humus, 10–40 mg/kg of phosphorus, 70–110 mg/kg of nitrogen, 300–500 mg per kg of soil of potassium). Meteorological conditions during the years of study (2021–2023) were contrasting: in 2022, HTC = 0.52 indicated average aridity and insufficient moisture with 0.81–0.82 in 2021 and 2023. The objects of the study were the varieties and hybrids of Sudan grass and sugar sorghum developed by the FSBSI “ARC “Donskoy”. As a result of hybridization on a sterile basis, there was developed a number of sorghumSudan hybrids (‘Jetta x Kudesnitsa’, ‘APV-1115 x Topolina’, ‘APV-1115 x FP’, ‘Dobrynya’, ‘Gordey’) and sweet sorghum hybrids (‘APV-115 x Yuzhnoye’, ‘Jetta x Severanay Vishnya’, ‘Duet’), allowing to obtain green mass yields of 51–63 and 47–49 t/ha, which was higher than the standard by 5–17 t/ha (10.8–37.0 %) and 5–7 t/ha (11.9–16.7 %) respectively. Using intervarietal hybridization, almost all varieties developed by the FSBSI “ARC “Donskoy” have been created. Among them there are the Sudan grass varieties ‘Alisa’, ‘Gratsiya’, ‘Anastasiya’, ‘Kudesnitsa’, ‘FP’ and the sweet sorghum varieties ‘Yuzhnoe’, ‘Feniks’, ‘Orfey’, ‘SK-20/334’, ‘Severanay Vishnya’ with a green mass yield of 40–48 and 34–38 t/ha, which is higher than that of standard varieties by 3–11 t/ha (8.1–29.7 %) and 7–11 t/ha (25.9–40.7 %), respectively. Thus, hybridization is the main method for developing new breeding material and combining the desired traits in new samples.

Влияние на метеорологичните фактори върху добива и евапотранспирацията на суданка за силаж, отглеждана като втора култура при неполивни и поливни условия

The aim of experiment was to establish the influence of meteorological factors during the vegetation period of sudan grass, grown as a second crop on yield and evapotranspiration The experiment was carry out during 2014 – 2017 period, on meadow – cinnamon soil in in the experimental field of the Stara Zagora Agricultural Institute. The data from irrigated (by 75% of FC) and non irrigated Sudan grass have been used. Dependencies between yield of dry biomass and meteorological factors have been established, as well as soil layer water depletion. The value of evapotranspiration and it’s formatting have been calculated (168.3– 183.7 mm without irrigation and 264.3 – 283.8 mm by optimum irrigation). The obtained yields of the sudanka strongly depend on the climatic conditions of the individual years of research, varying from 9800 kg.ha-1 to 11250 kg.ha-1

Selection and Validation of Reference Genes in Sudan Grass (Sorghum sudanense (Piper) Stapf) under Various Abiotic Stresses by qRT-PCR.

Quantitative reverse transcription PCR (qRT-PCR) can screen applicable reference genes of species, and reference genes can be used to reduce experimental errors. Sudan grass (Sorghum sudanense (Piper) Stapf) is a high-yield, abiotic-tolerant annual high-quality forage with a wide range of uses. However, no studies have reported reference genes suitable for Sudan grass. Therefore, we found eight candidate reference genes, including UBQ10, HIS3, UBQ9, Isoform0012931, PP2A, ACP2, eIF4α, and Actin, under salt stress (NaCl), drought stress (DR), acid aluminum stress (AlCl3), and methyl jasmonate treatment (MeJA). By using geNorm, NormFinder, BestKeeper, and RefFinder, we ranked eight reference genes on the basis of their expression stabilities. The results indicated that the best reference gene was PP2A under all treatments. eIF4α can be used in CK, MeJA, NaCl, and DR. HIS3 can serve as the best reference gene in AlCl3. Two target genes (Isoform0007606 and Isoform0002387) belong to drought-stress-response genes, and they are highly expressed in Sudan grass according to transcriptome data. They were used to verify eight candidate reference genes under drought stress. The expression trends of the two most stable reference genes were similar, but the trend in expression for Actin showed a significant difference. The reference genes we screened provided valuable guidance for future research on Sudan grass.

Cattle are more motivated for a high-concentrate diet than Sudan grass hay, despite low reticulorumen pH.

Subacute ruminal acidosis (SARA) is characterized by chronic low ruminal pH, and occurs for feedlot cattle fed high-concentrate diets. Forages slow digestion and reduce acid production. We aimed to assess how motivated finishing cattle are to access forage (Sudan grass hay, SG) via their willingness to interact with an electrified barrier. Reticulorumen pH was measured to relate the results to digestive health. Twenty-eight animals fed a high-concentrate ration ad libitum had access to 4L of one of two treatments (n = 14/treatment) fed 1×/d behind a barrier: 1) SG or 2) an additional offering of the normal ration (total mixed ration [TMR]). To access their treatment, the steer voluntarily pushed his muzzle against an electrified barrier. The electrical current was increased exponentially every 24h (0, 156, 312, 625, 1,250, 2,500, 5,000 µA) until the animal ceased accessing it. Visits to the treatment were recorded continuously 24h/d and reticulorumen pH was measured every 10min. Time with a reticulorumen pH below 5.8 was 348 ± 101 and 280 ± 76 min/24 h for SG and TMR animals, respectively; these durations meet the criterion for SARA. However, animals with access to SG were less likely to advance to the next current than TMR animals (P < 0.01) and were approximately 3× less willing to interact with higher currents than TMR (mean maximum current touched: 469 ± 169 and 1,380 ± 254 μA, respectively, mean ± SE, P = 0.01). Lower motivation to access SG was further demonstrated through fewer visits to the SG (2.4 ± 0.4 vs. 5.3 ± 0.6 #/d, P < 0.01), and less SG consumed than TMR (32.0 ± 0.1 vs. 74.0 ± 0.0 %/d, P < 0.01, measured as % due to weight differences of SG and TMR). Overall, finishing cattle valued the TMR more than SG, likely because of differences in the quantity offered, palatability, and familiarity. When rumen health was considered, SG animals visited more often (r = 0.5, P = 0.09) and showed fewer failed attempts (r = -0.5, P = 0.06) to access forage as the severity and duration of pH depression below 5.6, for example, increased. No measures of treatment use were related to pH depression for TMR animals (P ≥ 0.31). These findings provide evidence that cattle are motivated for Sudan grass hay when experiencing chronic low reticulorumen pH. However, they also contribute to the mixed evidence about the motivation for forage in this life stage, because, overall TMR was valued more highly than SG. Despite widespread pH depression, TMR cattle contrafreeloaded for additional concentration, demonstrating unexpectedly high motivation for this resource.

АГРОТЕХНИЧЕСКИЕ МЕРЫ БОРЬБЫ С ЗАСОРЕННОСТЬЮ ПОСЕВОВ ПОСРЕДСТВОМ ОБРАБОТКИ ПОЧВЫ В ОРОШАЕМОМ АГРОЦЕНОЗЕ

Purpose: to study methods to control weed infestation of crops by resource-saving methods of soil tillage, ensuring improvement of the phytosanitary condition of the irrigated agrocenosis. Materials and methods. The test scheme included studying the impact of moldboard plowing at different depths, flat-cut and surface primary tillage on weed infestation of crops. The features of agrotechnical methods in weed control were studied on experimental plots in Saratov region in 2021–2023. The experimental methodology is generally accepted. Results. The influence of different methods of primary tillage on weed infestation of agricultural crops in the crop rotation link under irrigation is considered. It is revealed that with the use of pre-sowing tillage and inter-row tillage during the crop vegetation period, a significant decrease in weed infestation of lands for the next crop is noted. For the first crop of the link – Sudan grass – the highest weed infestation was noted in the variant of minimum cultivation at 8–10 cm, the number of weeds was 26.0 pcs./sq. m. During the vegetation period, due to the high density of standing, the weed infestation of crops before harvesting decreased in all variants of the experiment. On the second crop of the link – spring wheat – and the third crop – soybean – the weed infestation varied insignificantly in all variants of the experiment. Weed control provided the biological yield of green mass of Sudan grass of 32.7–37.5 t/ha, spring wheat grain – 3.30–3.59 t/ha, soybean – 4.09–4.35 t/ha according to the variants of the experiment. No significant difference in the impact of the method of primary tillage on crop yield was revealed. Conclusions. Using the example of soybeans, Sudan grass and spring wheat, it has been proven that during their cultivation, using ploughing with furrow slice upside-down in the fall in combination with pre-sowing tillage and inter-row tillage during the crop vegetation is effective.

FORMATION OF THE YIELD OF THE ABOVE-GROUND MASS OF WHITE SWEETCLOVER IN SINGLE-SPECIES AND COMBINED CROPS IN THE CONDITIONS OF THE RIGHT-BANK FOREST STEPPE OF UKRAINE

FORMATION OF THE YIELD OF THE ABOVE-GROUND MASS OF WHITE SWEETCLOVER IN SINGLE-SPECIES AND COMBINED CROPS IN THE CONDITIONS OF THE RIGHT-BANK FOREST STEPPE OF UKRAINE

Productivity of sorghum crops in the southern chernozems of the Orenburg region

Both the crop production and animal husbandry industries are developed in the Orenburg region. For the normal development of the livestock industry, it is necessary to create a stable feed base. The Orenburg region is characterized by a sharply continental climate with frequent droughts. Therefore, it is necessary to select drought-resistant forage crops. Such crops include sorghum crops. In our research, hybrids and varieties of sugar sorghum, sorghum-sudangrass hybrid, Sudan grass for green fodder, as well as hybrids of grain sorghum for grain have been studied. It was revealed that in severe drought, the most productive for green fodder is sugar sorghum of the Silosnoye 88 variety, in medium drought – sorghum-sudangrass hybrid Boyarin. In terms of grain sorghum hybrids, the Willy hybrid turned out to be the best in terms of productivity.

SOIL CULTIVATION METHODS’ IMPACT ON SOIL WATER-PHYSICAL PROPERTIES UNDER RAINFED CONDITIONS OF SOUTHEAST KAZAKHSTAN

For the rational use of rainfed lands in Southeast Kazakhstan, the practical study aimed to determine the influence of different cultivation methods on the water-physical properties of the soil. The results revealed that, on average, for two years, the reserve of productive moisture in the ground during the spring with plowing at 20–22 cm was 127.8–146.4 mm, with minimal tillage at 8–10 cm (132.3–157.0 mm), and with zero tillage (122.2–140.8 mm) for all studied crops. With insufficient rainfall in summer, the moisture reserve decreased to 21.5–26.2 mm with plowing, 23.5–28.0 mm with minimal tillage, and 27.8–37.6 mm with zero tillage. In the studied crops, the soil density in the arable soil layer (0–30 cm) showed significant variations depending on the methods of soil cultivation. In spring, the soil was in a loose and weakly compacted state (1.17–1.22 g/cm3), and during harvesting, it increased and became dense (1.29–1.32 g/cm3), especially with zero tillage. Soil tillage methods provided the best structural aggregate condition (58%–71%) during the growing season of the studied crops of agronomically valuable aggregates (0.25–10 mm). However, the maximum content of structural aggregates (69%–71%) was evident with zero tillage by sowing safflower, spring barley, and Sudan grass. It indicates the excellent aggregate state of the soil under natural conditions with these crops. However, its minimum amount (58%) occurred with plowing (20–22 cm) under safflower. The water-resistant aggregate content was highest in no-tillage variants of the studied crops, varying between 17.6%–18.9%. With plowing, the water resistance of aggregates decreased to 13.1% under different crops. Over two years of research, the highest average yield of spring barley (2.42 t/ha) emerged with minimal tillage, while the lowest grain yield of Sudan grass (0.67 t/ha) came from plowing. As a result, the highest grain yields of spring barley, peas, and safflower emanated with minimal tillage, while in the Sudanese grass, with zero tillage.

Response of leaf day respiration in C4 plants to irradiance and vapour pressure deficit

Leaf day respiration rate (RL) plays a crucial role in the global carbon cycle. However, RL of C4 species has not been sufficiently studied and its response to environmental factors is largely unknown. This work studied the response of RL of three C4 species, Setaria viridis, Sorghum sudanense, and Zea mays, to alterations in the vapour pressure deficit (VPD) and irradiance of the growth environment. RL was estimated using the Kok method (RL Kok) and an improved method that combined gas exchange and chlorophyll fluorescence measurements (RL Yin). On average, shade treatment led to a 24% reduction in RL Yin and a 20% reduction in respiration in the dark (RDk), while a consistent VPD effect on RL was not observed. RL and RDk were positively correlated with nitrogen content per leaf area and net CO2 assimilation rate but were not correlated with the capacity of carboxylation enzymes. We found a non-significant light inhibition of respiration (1 ​± ​2%), contradicting the assumption that respiration is inhibited by light and affected by light intensity. Our findings indicate that assuming RL to be equal to RDk at the same temperature is a straightforward but reliable approach to model respiration of the examined C4 species.

Improving the Physical Properties and Water Retention of Sandy Soils by the Synergistic Utilization of Natural Clay Deposits and Wheat Straw

Improving the physical properties and water retention of sandy soils is of critical importance in arid and water-scarce regions such as Saudi Arabia. The impacts of organic amendments of different particle sizes coupled with natural clay deposits on improving the soil physio-chemical characteristics, nutrient availability, and growth of Sudan grass were investigated in this study. A loamy sand soil was amended with natural clay deposits at 2.5%, 5.0%, and 10% (w/w) application rates, and in combination with 1.0% (w/w) wheat straw of different particle sizes. The water infiltration, evaporation, and retention characteristics of the amended soil were studied for 9 weeks, and then Sudan grass was grown for 7 weeks. The impacts of the particle size of wheat straw on soil properties and nutrient availability were significant (p &lt; 0.05) when combined with clay deposits. The highest application rate of clay (10%) demonstrated the highest water content (20.63–21.73%), and increased P and K availability to 35.54 and 6980 mg kg−1, respectively, in soil, which were 33% and 88% higher, respectively, compared to the control. Plant N, P, and K concentrations were increased to 0.95%, 0.26%, and 4.33%, respectively, which were 2–3.5-fold higher than the control. Therefore, the integrated application of natural clay deposits and wheat straw of fine particle size could be an effective strategy in improving plant production in water-scarce regions.

Unveiling the soil physicochemical dynamics of bare soils in Southeast Kazakhstan: A comprehensive study in the Akdala Massif

This study addresses desertification in Kazakhstan's Akdala region, aiming to propose sustainable solutions by examining the effects of various plants on soil properties and nutrient dynamics. Desertification poses a threat to land productivity in arid areas, and this research aims to determine its impact on soil and identify plants for mitigation. Field experiments over three years in the Akdala region utilized crops such as rice, corn, soybean, sudan grass, and sorghum to assess their influence on key soil parameters. Results revealed diverse effects on soil bulk density, agronomically valuable aggregates, water-stable aggregates, labile and total organic carbon, easily hydrolyzable nitrogen, nitrate, available phosphorus, and exchangeable potassium. While no significant differences in bulk density were observed among crops, variations in surface and subsurface soil layers emphasized the importance of depth-specific considerations. Sorghum stood out as a particularly influential crop, significantly increasing labile and total organic carbon levels, highlighting its potential role in enhancing soil quality. The experiments were conducted on the fields of "Birlik" LLP in the Balkhash district of the Almaty region from 2015 to 2017. The chosen crops, each with distinct characteristics, provided a comprehensive understanding of their impact on soil dynamics. Advanced techniques for soil sampling and analyses ensured accurate measurements of various soil parameters. The study site's sharply continental climate, marked by temperature variations, snowy winters, and hot, dry summers, added complexity to the investigation due to its influence on plant growth and soil interactions. In conclusion, this comprehensive study offers valuable insights into the intricate relationships between different crops and soil parameters for combating desertification. The findings contribute significantly to the development of sustainable soil management practices, providing a foundation for identifying suitable crops for soil improvement in arid regions. By understanding how different plants impact soil properties, this research supports informed decision-making in agricultural practices, promoting the long-term sustainability of farming in regions vulnerable to desertification.

Effects of high nutrient and heavy metal containing soils on some chemical and biochemical features of Sudan grass

In this research we studied the effects of different soil amendments on the elemental composition and the activities of some enzymes of a Sudan grass variety (GK Csaba). In the pot experiment we used a soil with low heavy metal content as a plant grow media, as a control (C) we used the same soils „enriched” with a 20% wastewater sediment (WS) (originated from a former wastewater settling plant), a 10% compost (made of sewage sludge and green waste, SG), or their mix (C + 10% SG + 20% WS). The compost contained much more essential plant nutrients, while the wastewater-sediment was rich in toxic heavy metals compared to control soil. In this study, we determined the elemental composition of soil and organs of the plants (roots, leaves) and activities of some enzymes in leaves. Higher concentrations of all essential plant nutrient were detected in both roots and leaves of the treated plants. The concentration of copper and zinc were significantly higher (2 and 3 times higher, respectively) in plants grown in WS containing media (C+20% WS and C+10% SG + 20% WS). The concentrations of toxic heavy metals were higher in roots compared to leaves. As an exception, the cadmium concentration was nearly equal in the roots and the leaves, showing that this element's accumulation is not limited to the roots, but was also transported into the leaves. The activities of the examined enzymes (glucose-6 phosphate dehydrogenase, G6PDH; isocitrate-dehydrogenase, ICDH; peroxidase, POX) did not show significant changes in presence of WS and SG.

Effects of Silicon Alone and Combined with Organic Matter and Trichoderma harzianum on Sorghum Yield, Ions Accumulation and Soil Properties under Saline Irrigation

The action of silicon as a salt stress mitigator has been investigated in isolation, and its combined efficacy with other salt stress mitigators needs to be addressed. This work verified whether silicon, in combination with organic matter and Trichoderma harzianum, enhances the production of forage sorghum under saline irrigation and its effects on soil properties. The field experiment was conducted in Parnamirim (PE), a semiarid region of Brazil. Forage sorghum (Sorghum sudanense (Piper) Stapf) was irrigated with saline water (3.12 dS m−1) and subjected to the application of non-silicon, silicon alone, and silicon combined with Trichoderma and organic matter over three consecutive cuts (every three months after germination). Silicon applied in combination significantly increased the content of nutrient ions K+, P, Ca2+, and Mg2+ in sorghum leaves, stems, and panicles and increased P content in the soil by 170, 288, and 92% for the first, second, and third cuts, respectively. When silicon was applied in combination, sorghum’s dry and fresh matter (total yield for the three cuts) increased to 62.53 and 182.43 t ha−1, respectively. In summary, applying silicon (Si) combined with Trichoderma and organic matter promotes higher nutrient ion contents in soil and sorghum plants and a higher forage sorghum yield.

Cover cropping promotes soil carbon sequestration by enhancing microaggregate-protected and mineral-associated carbon

Cover cropping can improve soil C sequestration compared to no cover cropping, but the mechanism of C sequestration in soil aggregates and minerals needs more exploration. We explored C sequestration using C fractions in soil aggregates and minerals by cover crops in a five-year old summer cover crop – winter wheat (Triticum aestivum L.) rotation system at Changwu National Agroecology Experimental Station in the Chinese Loess Plateau. Three cover crops as soybean (Glycine max L., SB), sudangrass (Sorghum sudanense (Piper) Stapf, SG), soybean and sudangrass mixture (SS) were planted during summer fallow and incorporated into the soil two weeks prior to wheat planting each year. Soil samples at 0–10, 10–20, and 20–40 cm depths were collected at wheat harvest after 5-yr and analyzed for C fractions which were coarse particulate organic C (cPOC), intra-microaggregate fine particulate organic C (iPOC), free fine particulate organic C (fPOC), and mineral-associated organic C (MOC). The iPOC and MOC are considered as protected C against mineralization. Compared to no cover crop (CK), cover crops increased large macroaggregate proportion at 0–10 cm by 18–22 %, with SS having a greater mean-weight diameter (MWD) than other treatments. Cover crops had greater MOC, iPOC, and fPOC fractions than CK in most aggregate-size classes and the bulk soil at all depths, with SS having the greatest C fractions. The MOC was greater than any other C fractions, regardless of cover crop species. Cover cropping can enhance soil aggregation and C sequestration by increasing microaggregate-protected and mineral-associated C compared to no cover cropping, resulting in improved soil C stabilization. Cover crop mixture was more effective in promoting soil aggregate stability and C fractions than single cover crop species.