Sorghum Plants Research Articles

Novel Allelic Mutations in Dw3 Gene That Affect the Height of Sorghum Plants

Breeding for dwarfing traits in sorghum is crucial. However, only three genes (Dw1–Dw3) that control plant height have been mapped. In this study, 634 sorghum cultivars were collected to investigate plant height and genotypes. Four were genotyped Dw1DW2Dw3 (wild type) but with different plant heights, and they were selected to construct two populations and map new dwarf genes. Bulked segregant analysis with whole-genome resequencing of the two populations identified the candidate gene in one same genomic region—on chromosome 7. Then, it was narrowed down to a region containing nine genes. Amino acid and DNA sequence analysis of the parent and offspring plants revealed that two novel allelic mutations in the Dw3 gene play a role in reducing the plant height—8R262 or 8R417, including 1 bp substitution and 2 bp deletions. Furthermore, we sequenced 19 cultivars that primarily exhibited a “one-dwarf” hybrid or wild-type and presumed another allelic mutation via the amino acid alignment of 8R019, 8R100, and 8R402, which was another one-base substitution. These results indicate that multiple types of allelic mutations in the Dw3 gene should be considered when identified or applied.

Linking phylogenetic niche conservatism in bacterial communities in sorghum root compartments revealed by the Hongyingzi cultivar.

The root system harbours complex bacterial communities, which are critical for plant growth and health. Significant differences exist between bacterial communities in the root compartments; however, limited reports have explored their phylogenetic composition and niche conservatism in the root system of sorghum. We used the sorghum Hongyingzi cultivar as test plant, and applied 16S rRNA high-throughput sequencing and various statistical approaches. Phylogenetic composition of bacterial communities in root compartments were primarily driven by closely related species with similar environmental adaptations. We also found evidence of phylogenetic niche conservatism in bacterial communities for edaphic factors in the various root compartments, with pH and available N playing essential roles in shaping community composition. Environmental threshold analysis revealed threshold ranges of dominant taxa for pH and available N, indicating wider adaptive thresholds for more abundant taxa. Reconstruction of ancestral states suggested evolutionary changes in adaptability of certain bacterial taxa to edaphic factors, suggesting a shift towards slightly acidic, high N environments and reflecting the prolonged mutual interaction between bacteria and plants in cultivated soils. These findings enhance our understanding of environmental responses and evolutionary dynamics of root-associated microbiota in young sorghum plants and provide novel insights into ecological adaptations, shedding light on their responses to environmental factors. Our study contributes to a better understanding of the ecological dynamics of root-associated microbiota and offers analytical pathways for exploring the nutritional regulation of root microbiota.

Isotopic analysis of modern sorghum and finger millet from different altitudes in Ethiopia: implications for ancient farming practices

C4 crops such as sorghum (Sorghum bicolor) and finger millet (Eleusine coracana) have played a significant role in the economic livelihood in arid and semi-arid zones of tropical and sub-tropical Africa since prehistoric times. However, to date, our knowledge of their past management practices is limited. Stable isotope analysis of archaeobotanical remains has been recognized as a valuable tool for reconstructing past agricultural practices, e.g. water management, and fertilization. Nonetheless, our limited understanding of the isotopic variability of C4 plants calls for further research on modern plant before application to archaeobotanical remains. In this paper, we aim to enhance our understanding of modern C4 botanical remains' isotopic variability by analyzing sorghum and finger millet plants. These crops were cultivated according to traditional local practices and collected from ten villages located in the Konso Zone (South Ethiopia) and Tigray Regional State (North Ethiopia), where they are among the daily ingredients for food, and traditional alcoholic and non-alcoholic drinks. We analyzed carbon and nitrogen stable isotopes of seeds and biosilica content in chaff, as it has been suggested that a relationship can exist between silicon and C:N. Carbon isotope values show significant variability, positively correlated with altitude. By demonstrating the sensitivity of C4 grain carbon stable isotope to altitude variations, which are likely connected to water availability, this study offers invaluable insights for the accurate assessment of isotopic values derived from ancient C4 crops. The absence of significant correlations with δ15N suggests that nitrogen isotope values may be less effective for understanding environmental variations in this kind of context. This highlights the limitations of nitrogen isotope data for interpreting ancient agricultural practices and underscores the importance of relying more on carbon isotopes for insights related to environmental conditions and altitude. Furthermore, we confirm that the amount of assimilated carbon may depend also on the biosilica content, which is in turn modulated by environmental parameters such as water availability or soil silicon levels.

Effect of Fall- and Spring-Planted Cover Crops and Residual Herbicide on Emergence Dynamics of Glyphosate-Resistant Kochia (Bassia scoparia)

Abstract Two separate field experiments were conducted during the 2021-22 and 2022-23 growing seasons at Kansas State University Agricultural Research Center near Hays, KS to understand the emergence dynamics of glyphosate-resistant (GR) kochia [Bassia scoparia (L.) A. J. Scott] as influenced by fall- and spring-planted cover crops (CC) and residual herbicide. Study sites were under winter wheat (Triticum aestivum L.)-sorghum [Sorghum bicolor (L.) Moench]-fallow rotation with a natural seedbank of GR B. scoparia. In experiment 1, fall-planted CC mixture (triticale/winter peas/radish/rapeseed) was planted after wheat harvest and terminated at triticale [xTriticosecale Wittm. Ex A. Camus [Secale x Triticum] heading stage (next spring before sorghum planting). In experiment 2, spring-planted CC mixture (oats/barley/spring peas) was planted in sorghum stubbles and terminated at oats (Avena sativa L.) heading stage. Four treatments were established in each experiment: (1) nontreated control (no CC and no herbicide), (2) chemical fallow (no CC but glyphosate + acetochlor/atrazine or flumioxazin/pyroxasulfone + dicamba were used to control weeds), (3) CC terminated with glyphosate, and (4) CC terminated with glyphosate plus residual herbicide (acetochlor/atrazine for fall-planted CC and flumioxazin/pyroxasulfone for spring-planted CC). Results indicated that fall-planted CC delayed GR B. scoparia emergence by 3 to 5 weeks whereas spring-planted CC delayed emergence by 0 to 2 weeks compared to nontreated. Fall-planted CC terminated with glyphosate plus acetochlor/atrazine reduced the cumulative emergence of GR B. scoparia by 90 to 95% compared to nontreated across both yrs. Similarly, spring-planted CC terminated with glyphosate plus flumioxazin/pyroxasulfone reduced the cumulative emergence of GR B. scoparia by 83 to 90% compared to nontreated. These results suggest that fall- or spring-planted CC in combination with residual herbicide at termination can be utilized for GR B. scoparia suppression. Results from this study will help in developing prediction models for GR B. scoparia emergence under different CC strategies.

Evaluation of Ratoon Potential and Yield of Some Sorghum Varieties (Sorghum bicolor L)

Sorghum production needs to be increased to meet food or feed needs because sorghum grain has nutritional qualities that are comparable to other grains such as corn. One of the advantages of the sorghum plant is the growth of new shoots from the base of the harvested stem which produces new plants, ratoon, that grow until they can be harvested. This experiment examines the ratoon potential of 5 sorghum varieties, Bioguma, Samurai, Pahat, Suri4, and the local Gando Keta variety so that we can utilize ratoon technology on these sorghum varieties. The experiment was carried out in a greenhouse using a Completely Randomized Design. It can be confirmed from this experiment that the dry matter weight of the main plants is higher compared to the ratoon plants' dry matter weight, however, the yield of the ratoon was higher than that of the main plants. Seed size contributes to the higher yield of the ratoon plants. Among all the varieties tested, Suri4 and Pahat show the best ratoon potential. Gando Keta, the local variety, has the lowest grain yield of main and ratoon compared to the other varieties.

Effect of Green Cowpea Manure on the Quality Properties of Sandy Soils Under the Specific Conditions of the Dry Climate in Romania

This study was carried out on the rotation of cowpea-rye + cowpea in successive crops for green manure-sorghum grains, with the objective of increasing the fertility of sandy soils by incorporating green cowpea manure into the soil in combination with chemical fertilization with NPK. In this sense, after harvesting the rye plant, the cowpea was sown, which was then incorporated into the soil during the formation of the beans in the pod. Before incorporating the cowpea biomass into the soil, the initial fertility status of the soil was assessed, and in the spring, the soil was sown with sorghum grain in two fertilization variants (N80P80K80 and N150P80K80). The soil chemical analyses carried out at the end of the vegetation cycle of the sorghum plant showed that by incorporating 52.4 t/ha green cowpea biomass (9.24 t/ha dry biomass), the quality properties of the soil were significantly improved, with annual increases of 0.17–0.29 g/kg in total nitrogen, 9.5–13.33 mg/kg in extractable phosphorus, 11.33–24 mg/kg in exchangeable potassium, and 0.08–0.12 g/kg in organic carbon, also depending on the sorghum fertilization system. It has also been shown to reduce the acidity of the soil pH and improve the water holding capacity of the soil.

Sorghum segmentation and leaf counting using in silico trained deep neural model

AbstractThis paper introduces a novel deep neural model for segmenting and tracking the number of leaves in sorghum plants in phenotyping facilities. Our algorithm inputs a sequence of images of a sorghum plant and outputs the segmented images and the number of leaves. The key novelty of our approach is in training the deep neural model. Manual annotations are tedious, and we have developed a procedural three‐dimensional (3D) sorghum model that provides detailed geometry and texture to generate photorealistic 3D models. The overall shape of the sorghum leaf geometry is determined by its skeleton, and it is detailed by a procedural model that varies its curvature, width, length, and overall shape. The color is determined by using a Monte Carlo path tracer. We mimic the illumination of the phenotyping facility and use reflectance and transmittance on sorghum surfaces to determine the color of the leaves. The 3D procedural model allows us to generate photorealistic and segmented images that we use to train a deep neural model. Our segmentation provides a mean intersection over union score of 0.51, resulting in leaf counting accuracy within the 90% confidence interval for the human counts.

Transcriptomic Insights into Drought Survival Strategy of Sorghum bicolor (L.) Moench during Early Growth under Polyethylene Glycol-Simulated Conditions

Drought stress during sorghum emergence significantly affects seedling establishment, adversely affecting both emergence and population growth. This study investigates drought tolerance mechanisms during sorghum germination by analyzing physiological changes and transcriptomic data from two lines: W069 (drought tolerant) and W040 (drought sensitive). Under drought conditions, a phenotypic analysis revealed that W069 exhibited longer shoots and roots than W040. Additionally, physiological data indicated higher osmotic substance and lower malondialdehyde levels in W069. Using Kyoto Encyclopedia of Genes and Genome analyses, we identified three key pathways (starch and sucrose metabolism, phenylpropanoid biosynthesis, and phytohormone signaling) as pivotal in the drought response during seed germination in sorghum plants. Expression profiling revealed that most drought tolerance-related genes in the three key pathways were expressed at higher levels in the drought-tolerant cultivar W069, possibly explaining its greater stress tolerance. These findings enhance our understanding of drought-responsive gene networks in sorghum seed germination, offering potential target genes and strategies for enhancing drought tolerance in this crop.

Effect of Rabbit Urine Bio Fertilizer and NPK on Vegetative Variables of Sorghum (Sorghum bicolor L.)

Sorghum (Sorghum bicolor L.) is a plant that requires more N nutrients than other nutrients. The abundance and affordability of rabbit urine bio fertilizer can reduce the cost of cultivation production inputs due to the high price of inorganic fertilizers. Rabbit urine contains higher N nutrients compared to other livestock urine. This study aims to obtain a combination of Rabbit Bio Urine (BUK) fertilizer concentration and NPK fertilizer dosage that can give the best results on the growth of sorghum plants (Sorghum bicolor L.). The research method used is a non-factorial Randomized Group Design (RAK) consisting of 6 levels, namely: P1 (BUK 0 ml/L + 100% NPK), P2 (BUK 41 ml/L + 80% NPK), P3 (BUK 27 ml/L + 80% NPK), P4 (BUK 18 ml/L + 80% NPK), P5 (BUK 9 ml/L + 80% NPK), and P6 (BUK 5 ml/L + 80% NPK). The application of rabbit bio urine fertilizer gives a real effect on the parameters of plant height and stem diameter at the age of 36 HST and 42 HST. In the parameter of the number of leaves, rabbit bio urine fertilizer and NPK gave no significant effect at all observation times. The P2 treatment (BUK 41 ml/L + NPK 80%) gave the highest results in the parameters of plant height at the age of 36 HST and 42 HST which amounted to 98,1 cm and 123,7 cm. In the parameter of stem diameter, the highest result was obtained by P1 (BUK 0 ml/L + NPK 100%) which amounted to 14,8 mm. Keywords : N Nutrient, Rabbit Urine Bio Fertilizer, Sorghum

Cover crop root exudates impact soil microbiome functional trajectories in agricultural soils

BackgroundCover cropping is an agricultural practice that uses secondary crops to support the growth of primary crops through various mechanisms including erosion control, weed suppression, nutrient management, and enhanced biodiversity. Cover crops may elicit some of these ecosystem services through chemical interactions with the soil microbiome via root exudation, or the release of plant metabolites from roots. Phytohormones are one metabolite type exuded by plants that activate the rhizosphere microbiome, yet managing this chemical interaction remains an untapped mechanism for optimizing plant-soil-microbiome interactions. Currently, there is limited understanding on the diversity of cover crop phytohormone root exudation patterns and our aim was to understand how phytochemical signals selectively enrich specific microbial taxa and functionalities in agricultural soils.ResultsHere, we link variability in cover crop root exudate composition to changes in soil microbiome functionality. Exudate chemical profiles from 4 cover crop species (Sorghum bicolor, Vicia villosa, Brassica napus, and Secale cereal) were used as the chemical inputs to decipher microbial responses. These distinct exudate profiles, along with a no exudate control, were amended to agricultural soil microcosms with microbial responses tracked over time using metabolomes and genome-resolved metatranscriptomes. Our findings illustrated microbial metabolic patterns were unique in response to cover crop exudate inputs over time, particularly by sorghum and cereal rye amended microcosms. In these microcosms, we identify novel microbial members (at the genera and family level) who produced IAA and GA4 over time. Additionally, we identified cover crop exudates exclusively enriched for bacterial nitrite oxidizers, while control microcosms were discriminated for nitrogen transport, mineralization, and assimilation, highlighting distinct changes in microbial nitrogen cycling in response to chemical inputs.ConclusionsWe highlight that root exudate amendments alter microbial community function (i.e., N cycling) and microbial phytohormone metabolisms, particularly in response to root exudates isolated from cereal rye and sorghum plants. Additionally, we constructed a soil microbial genomic catalog of microorganisms responding to commonly used cover crops, a public resource for agriculturally relevant microbes. Many of our exudate-stimulated microorganisms are representatives from poorly characterized or novel taxa, revealing the yet to be discovered metabolic reservoir harbored in agricultural soils. Our findings emphasize the tractability of high-resolution multi-omics approaches to investigate processes relevant for agricultural soils, opening the possibility of targeting specific soil biogeochemical outcomes through biological precision agricultural practices that use cover crops and the microbiome as levers for enhanced crop production.BPG5Z_iDvqR4KrAs2TcSTiVideo

Silicon Treatment on Sorghum Plants Prior to Glyphosate Spraying: Effects on Growth, Nutrition, and Metabolism

Silicon Treatment on Sorghum Plants Prior to Glyphosate Spraying: Effects on Growth, Nutrition, and Metabolism

Improving Sorghum (Sorghum bicolor L.) Production through the Use of Azospirillum sp. AZ6 and Trichoderma harzianum T4-Based Biostimulants

Objectives: The objective(s) of the present experiment was to evaluate the effect of Azospirillum sp. AZ6 and Trichoderma harzianum T4-based biostimulants formulated in Mali on the growth and yield of Sorghum in Mali field during monsoon season. Study Design: The experiment was conducted in a completely randomized block design with three treatments. The blocking factor was the direction of rainwater runoff. Methodology: The study was carried out in the rural commune of Ouéléssebougou located in the Sudanian. The sorghum seeds inoculated or non-inoculated with Azozpirillum sp. AZ6, Trichoderma harzianum T4, were randomly sown in single-cropped with no nitrogen (N) application. For the control, 100% dose of N was applied at sowing time at 120 kg/ha. Sorghum plant height, sorghum yield, number of panicles and the weight of 1000 grains weight were evaluated. Results: The salient findings showed a significant increase of the parameters examined by Azospirillum sp. AZ6 and Trichoderma harzianum T4-based biostimulants. Inoculation of AZ6 improved sorghum yield by 68,25%, while T4 by 8.73% in comparison with the control. Conclusion: It is evident that Azospirillum sp. AZ6 and Trichoderma harzianum T4 are suitable for inoculating sorghum (Sorghum bicolore L.). Azospirillum sp. AZ6 produced the highest plant height, yield, number of panicles, and 1000 grain weight relative to Trichoderma harzianum T4 and the non-inoculated control. Therefore, this suggest that Azospirillum sp. AZ6 is suitable for large scale application in sorghum fields to reduce the production costs and increase yield while reducing N fertilizer application rate

Increasing Fertilization Efficiency of Biomass Ash by the Synergistically Acting Digestate and Extract from Water Plants Sequestering CO2 in Sorghum Crops.

The utilization of biomass ash in sustainable agriculture and increasing its fertilizing efficiency by biological agents, potentially sequestering CO2, have become important issues for the global economy. The aim of this paper was to investigate the effects of ash from sorghum (Sorghum bicolor L. Moench) and Jerusalem artichoke (Helianthus tuberosus L.) biomass, a biogas plant digestate, and a Spirodela polyrhiza extract, acting alone or synergistically, on soil fertility and the development, health and physiological properties of sorghum plants. The results show novel information concerning differences in the composition and impact of ash, depending on its origin, soil properties and sorghum plant development. Sorghum ash was more effective than that from Jerusalem artichoke. Ash used alone and preferably acting synergistically with the digestate and Spirodela polyrhiza extract greatly increased soil fertility and the growth, biomass yield and health of sorghum plants. These improvements were associated with an increased chlorophyll content in leaves, better gas exchange (photosynthesis, transpiration, stomatal conductance), greater enzyme activity (acid and alkaline phosphatase, RNase, and total dehydrogenase), and a higher biomass energy value. The developed treatments improved environmental conditions by replacing synthetic fertilizers, increasing the sequestration of CO2, solving the ash storage problem, reducing the need for pesticides, and enabling a closed circulation of nutrients between plant and soil, maintaining high soil fertility.

249 Effects of sorghum silage kernel processing on growth performance and blood metabolites of beef heifers

Abstract Our previous studies suggested that using a shredlage (SHRD) processor or a conventional (CONV) sorghum kernel processor leads to similar apparent total tract nutrient digestibility of whole plant sorghum silage (WPSS). This study evaluated the effects of feeding WPSS harvested using different kernel processors (CONV vs. SHRD), on growth performance of beef heifers. Grain sorghum (ADV2450IG; Advanta Seeds, Argentina) was harvested at the hard-dough stage with a Class Jaguar 950 (Harsewinkel, Germany), switching the kernel processor to generate the forage material for the two treatments: CONV and SHRD. The material was bagged in two 2.7 m diameter bags and allowed to ferment for 3 mo. Black Angus heifers [n = 96; body weight (BW) = 15 ± 1 mo, 249.6 ± 28.6 kg] were blocked by initial BW, and randomly assigned to pens (8 heifers/pen, 6 pens/treatment). Diets consisted, all in DM basis, of WPSS of each respective type (SHRD or CONV) at 90.5%, expeller soybean meal at 7.0%, and a vitamin-mineral-NNP concentrate at 2.5%. The experiment consisted of a 14-d adaptation period, followed by a 56-d growing period; and feed was offered once daily. Data were analyzed as a randomized complete block design, using pen as the experimental unit, with the fixed effect of treatment and the random effect of block. No differences were observed (P > 0.10) for final BW, dry matter intake, and residual feed intake. However, CONV fed heifers tended to gain more BW per day (ADG, 0.83 vs. 0.77 kg/d; P = 0.07) and had greater gain to feed ratio (GF, 0.083 vs. 0.075 kg/kg; P = 0.05) and greater Kleiber ratio (KR, 12.1 vs 11.2 g/kg; P = 0.05) as compared with SHRD fed heifers. Furthermore, performance calculated dietary Net Energy of gain (NEg) in CONV fed heifers tended to be greater than that for SHRD (0.70 vs. 0.65 Mcal/kg of diet DM, respectively; P = 0.06). Moreover, blood serum from CONV fed heifers had 16% greater total bilirubin (P = 0.04), 12% greater cholesterol (P = 0.02), and slightly greater non esterified fatty acids (P = 0.03) concentrations. Noteworthy, serum concentrations of total bilirubin were correlated (P ≤ 0.03) with ADG, GF, KR and NEg. In conclusion, the type of kernel processor utilized for the harvest of sorghum silage may have an impact on feed efficiency of beef cattle. These differences could be related to changes on the site of utilization of nutrients, particularly starch; what could also explain the differences on blood metabolites. However, further research is needed to help explain these findings.

Agronomic potential of different fermented organic composts based on agro-industrial plant waste.

Organic composts such as "bokashi", obtained from the fermentation of bran mixtures and inoculated with microorganisms, improve soil characteristics. In Brazil, the most widely used formulation for the production of this compost is obtained from a mixture of wheat and castor bean bran, but both have a high monetary cost. Replacing these components with regionally available sources represents the possibility of reducing costs and making more sustainable use of this waste. The aim of this study was to analyze the chemical characteristics and determine the availability of nitrogen for the plants. The study was divided into two stages, consisting of an incubation test in the laboratory and a bioassay in the greenhouse using forage sorghum as an indicator species. In the laboratory trial, the treatments consisted of two raw material sources with a low C/N ratio (castor bean bran-CAB and cottonseed bran-COB), corresponding to 40% of the mixture; three sources with a high C/N ratio (wheat bran-WHB or rice bran-RIB), gradually replaced by passion fruit peel bran-PFPB), corresponding to 60% of the mixture. The materials were mixed, moistened, inoculated with microorganisms (Embiotic®) and kept in sealed containers with a capacity of 620 cm3 for 21days. In the greenhouse, in addition to the aforementioned treatments, seven controls were included: no addition of organic and synthetic N sources; ammonium nitrate; CAB; COB; WHB; RIB and PFPB. In the second stage, dry mass production and N content in sorghum plant tissues were determined, and the rates of N availability were estimated. It was found that the pH of the standard compost was 4.75, and in the other formulations it ranged from 4.62 to 5.3, the highest values being observed when WHB was fully replaced by RIB There was a significant difference in the EC values, but all were well below the value considered adequate. Replacing CAB with COB and WHB with RIB and PFPB resulted in a reduction in N content and an increase in the C:N ratio. Replacing WHB with PFPB led to an increase in K content and a reduction in P and Mg content. In the bioassay, the highest biomass production was in the treatments with the fermented composts, and the highest biological recovery of N was obtained in the ammonium nitrate treatment, followed by the CAB, COB and WHB treatments.

Transcriptome analysis of potassium-mediated cadmium accumulation in sweet sorghum

Cadmium (Cd) pollution in the soil is a serious environmental issue worldwide. Phytoextraction of Cd-polluted soil is a cost-effective, sustainable and environmentally-friendly strategy. Agricultural fertilizer management is beneficial for promoting the Cd phytoremediation efficiency. Potassium (K) is the nutrient required in the largest amount cation by plants. Sweet sorghum exhibits a substantial phytoremediation potential of Cd-polluted soil. Clarifying the mechanism of K-mediated Cd accumulation in sweet sorghum is imperative. Sweet sorghum plants were grown hydroponically with an extra K supply in the presence or absence of Cd treatment. An extra K application significantly increased plant growth under non-Cd addition, while K lost the profitable effect under Cd stress. K supplementation remarkably enhanced Cd concentrations and Cd accumulation in shoots and roots of sweet sorghum. Transcriptome analysis demonstrated that zinc ion transport, cysteine and methionine metabolism, flavonoid biosynthesis and phenylpropanoid biosynthesis pathways might contribute to the increased Cd accumulation as affected by an extra K supply. Furthermore, SbZIP9, SbSTP8, SbYS1, SbMAG and SbFOMT-like were targeted as they closely correlated with both plant growth and Cd stress in sweet sorghum. SbFOMT-like showed an independent pathway, while SbZIP9, SbSTP8, SbYS1 and SbMAG displayed positive correlations mutually. Notably, SbZIP9 and SbFOMT-like were highly expressed when compared with other target genes. Taken together, SbZIP9 and SbFOMT-like were upregulated and downregulated by an extra K supply under Cd stress, suggesting that SbZIP9 and SbFOMT-like enhances and declines Cd accumulation as regulated by K addition in sweet sorghum respectively.

Winged Melanaphis sorghi1 Respond More to the Odor of Nondamaged than Damaged Sorghum Plants

Winged Melanaphis sorghi1 Respond More to the Odor of Nondamaged than Damaged Sorghum Plants

Nitrate Reductase and Glutamine Synthetase Enzyme Activities and Chlorophyll in Sorghum Leaves (Sorghum bicolor) in Response to Organic Fertilization

Sorghum is a plant that mainly requires chemical nitrogen fertilization. There are organic fertilizers that can provide nutrients to plants with great benefits to the soil, such as chicken manure. To determine the influence of organic fertilization on nitrate reductase (NR), glutamine synthetase (GS), and the amount of chlorophyll, sorghum plants were grown using the following four treatments: soil (T1), soil + chicken manure 100 kg ha−1 of nitrogen (N) (T2), soil + chicken manure 200 kg ha−1 N (T3), and soil + ammonium sulfate 100 kg ha−1 N (T4). Leaves were sampled in the vegetative stage (VS), the reproductive stage (RS), and the maturation stage (MS). The highest NR activity occurred in plants with T2 and T3 in the VS. The highest GS activity was in T3 and T4 in the RS. The amount of chlorophyll a was the same in all phenological stages. However, the amount of chlorophyll b was influenced by the type of fertilization at different phenological stages. Organic fertilizers (OF) produced the highest NR activity. On the other hand, GS activity was higher with chemical fertilization (T4), which was equal to the second dose of organic fertilization (T3). Finally, chlorophyll a and b were influenced by both types of fertilization, and was different from T1.

Diversity and pathogenicity of Fusarium spp. isolated from cultivated sorghum stems and roots in eastern Australia

AbstractStalk and root rots of cultivated sorghum (Sorghum bicolor) are caused by several Fusarium species worldwide. This study evaluated Fusarium diversity, pathogenicity and population structure amongst 212 isolates obtained from 169 sorghum plants from commercial field crops in eastern Australia. Sequences of translation elongation factor‐1α (tef‐1α), RNA polymerase II largest subunit (rpb1), RNA polymerase II second largest subunit (rpb2) and calmodulin (cmdA) were used to construct multilocus phylogenies that enabled the identification of 16 Fusarium species in Fusarium chlamydosporum species complex (FCSC), Fusarium fujikuroi species complex (FFSC), Fusarium incarnatum‐equiseti species complex and Fusarium oxysporum species complex (FOSC). The majority of isolates (n = 171) belonged to FFSC. The pathogenicity of 17 selected isolates was determined by artificial inoculation of sorghum seedlings and completing Koch's postulates. Isolates of species in FFSC were significantly (p < 0.05) more aggressive as root pathogens in sorghum seedlings than isolates of other species tested and widely distributed across all sampling sites. Amongst the 35 isolates of FOSC, 26 belonged to Fusarium cili, which is only known as an endophyte from healthy roots of Rosa roxburghii in China. Fusarium sporodochiale (in FCSC) and Fusarium contaminatum (in FOSC) are reported as sorghum seedling root rot pathogens for the first time.

Integration of transcriptional responses in cold contrasting sorghum genotypes under low temperatures

AbstractSorghum is a crop that is susceptible to low temperatures. However, due to the extreme global temperatures, new genotypes have been bred to adapt better to cold climates. Therefore, to better understand the metabolic and molecular differences that may contribute to the improved cold tolerance of these genotypes, it is essential to investigate whether specific molecules play a key role in determining the degree of sorghum tolerance. Furthermore, identifying genes associated with cold tolerance may assist in the development of more robust and productive sorghum cultivars. Here, we analysed the changes in selected elements of the antioxidant metabolism, genes, and miRNAs in two sorghum varieties with different degrees of tolerance to cold stress at different times of exposure to cold stress. The high expression of SbCBF6 in response to cold treatment in early time in the tolerant variety suggests its involvement in the cold response, thereby facilitating a better adaptation of the plant to cold conditions. MiR398 and miR394 showed contrasting behaviour in both varieties in low temperatures, resulting in interesting miRNAs in the degree of sorghum tolerance. MiR319, a marker for the selection of cold‐tolerant cultivars, presents a decrease, suggesting that the better capacity to repress the expression of several members of TCP family of transcription factor genes might be involved in better tolerance to cold stress. This study shows the changes of molecules of interest in response to cold stress in sorghum, marking the difference between cold‐susceptible and cold‐tolerant sorghum plants, which can contribute to selecting tolerant genotypes, allowing new strategies to enhance crop productivity and food security, in regions where low temperatures significantly constrain crop growth and yield.