Pearl Millet Research Articles

Do rainfed production systems have lower environmental impact over irrigated production systems?: On -farm mitigation strategies

The intensive agriculture practices improved the crop productivity but escalated energy inputs (EI) and carbon foot print (CF) which contributes to global warming. Hence designing productive, profitable crop management practices under different production systems with low environmental impact (EI and CF) is the need of the hour. To identify the practices, quantification of baseline emissions and the major sources of emissions are required. Indian agriculture has diversified crops and production systems but there is dearth of information on both EI and CF of these production systems and crops. Hence the present study was an attempt to find hot spots and identify suitable strategies with high productivity, energy use efficiency (EUE) and carbon use efficiency (CUE). Energy and carbon balance of castor, cotton, chickpea, groundnut, maize, rice (both rainfed and irrigated), wheat, sugarcane (only irrigated), pigeon pea, soybean, sorghum, pearl millet (only rainfed) in different production systems was assessed. Field specific data on different crop management practices as well as grain and biomass yields were considered. Rainfed production systems had lower EI and CF than irrigated system. The nonrenewable sources of energy like fertilizer (64 %), irrigation (78 %), diesel fuel (75 %) and electricity (67 %) are the major source of energy input. Rainfed crops recorded higher CUE over irrigated condition. Adoption of technologies like efficient irrigation strategies (micro irrigation), enhancing fertilizer use efficiency (site specific nutrient management or slow release fertilizer), conservation agriculture (conservation or reduced tillage) rice cultivation methods (SRI or Direct seeded rice) were the mitigation strategies. These results will help policy makers and stake holders in adoption of suitable strategies for sustainable intensification.

APPLICATION OF A HYDROPHILIC BIOPOLYMER OBTAINED FROM PENNISETUM GLAUCUM SEED FIBRE AS BINDER IN ALBENDAZOLE CHEWABLE TABLET FORMULATION

Natural polymers with enhanced binding properties in tablet formulation continue to be highly sought over synthetic materials. This study aims to evaluate the binding properties of a hydrophilic biopolymer derived from the modification of the seed fibre of Pennisetum glaucum (TP) in the manufacture of albendazole chewable tablets. Dry TP seeds were steeped in water for 24h, washed, wet milled, and the fibre separated from the starch by washing slurry with water through a muslin cloth. Fibre of TP was dried at 60°C, screened through 180µm sieve (TP-NF). An 800 g of TP-NF was dispersed in 3.0L of 3.5% w/v sodium hypochlorite for 30 min, washed with distilled water to neutral pH, dispersed in 90% v/v ethanol for 10 min and dried at 60°C (TP-MC). The fibre was classified (180µm) and characterised using standard methods. Albendazole tablets were formulated using 5, 7.5, 10 and 15% w/w of the biopolymers by wet granulation. Avicel PH 101 was used as comparing standard binder. The dried albendazole granules were micromeritically evaluated while tablets made from the granules were evaluated for their physical properties, assay and dissolution studies. TP-MC powder flowed and compressed better than TP-NF, while albendazole granules had better flow and compressibility than TP-NF and TP-MC. The albendazole tablets were fairly strong and varied minimally in weight. Friability was <1%, and > 80% of albendazole was released from the tablets within 15 min. TP-MC served more effectively than TP-NF and compared favourably with Avicel PH 101 as binder in the formulation of albendazole tablets.

Impact of cold plasma on pearl and barnyard millets' microbial quality, antioxidant status, and nutritional composition

In the quest for sustainable and innovative food processing technologies, cold plasma treatment has emerged as a promising approach with the potential to enhance grains' nutritional and functional properties. This study investigates the impact of cold plasma treatment on two millet varieties, namely pearl millet (Pennisetum glaucum) and barnyard millet (Echinochloa spp.). This study analyzed the effect of Cold plasma on the proximate composition, vitamin content, physiochemical property, anti-nutrient factor, bioactive compounds, antioxidant activity and microbial count of millets. Pearl millet (RP) and Barnyard millet (RB) (native), cold plasma treated Pearl (CP) and Barnyard (CB) (2 kV, 5 min) were characterized. A noticeable change was found in fat, vitamin B-complex content and antioxidant activity. Furthermore, the microbial count analysis revealed that cold plasma treatment induced substantial reductions in bacterial and yeast populations, underscoring the technology's effectiveness in enhancing the safety and extending the shelf-life of millet grains. Treatments of samples led to a reduction of phytic acid and tannin. In pearl millet, tannin content decreased by 18%, and phytic acid content was reduced by 57%. In barnyard millet, there was a substantial (24%) reduction in tannin content and a 61% decrease in phytic acid. Total Flavonoid content (TFC) and Total Phenolic content (TPC) also decreased after treatment. But this treatment led to an increase in fat content by 43% and 87% in CP and CB, respectively. These alterations offer new insights into the potential of cold plasma treatment as a means to enhance the nutritional quality and safety of millets. The results of this study contribute to the growing body of knowledge on innovative food processing techniques for improving the nutritional value of grains.

Diseases prevalent in Kharif crops grown in Barmer district of Rajasthan, India

In the Kharif season, pearl millet (Pennisetum glaucum) is the predominant crop of the Barmer district followed by cluster bean (Cyamopsis tetragonoloba) and moth bean (Vigna aconitifolia). Sesame (Sesamum indicum) and green gram (Vigna radiata) are other important Kharif oilseed and pulse crops, respectively. A survey was conducted to determine the status of major diseases of Kharif crops grown in the Barmer district of the Marwar region of Rajasthan, India. Five blocks and three villages in each block were surveyed through a random field survey method during the collection of diseased samples every Sunday for the practical classes of agricultural students of the College of Agriculture, Baytu; in August and September 2023. Per cent disease incidence was recorded on randomly selected plants in a particular field of selected location. The incidence of diseases was observed based on typical field symptoms and later the association was confirmed through microscopic examinations in the laboratory. In survey, yellow mosaic (virus), leaf crinkle/ curl (virus), bacterial leaf spot/ blight (Xanthomonas phaseoli) of green gram;green ear/ downy mildew (Sclerospora graminicola), rust (Puccinia substriata) and blast (Pyricularia grisea) of pearl millet; Phytophthora stem blight (Phytophthora parasitica var. sesame) and phyllody (Phytoplasma) of sesame; yellow mosaic (virus)and bacterial leaf spot/ blight (Xanthomonas axonopodis pv. cyamopsidis) of cluster beanwere recorded with >50% incidence. However; charcoal rot (Macrophomina phaseolina), web blight (Rhizoctonia solani), Cercospora leaf spot (Cercospora canescens) and anthracnose (Colletotrichum lindemuthianum) of green gram; Alternaria blight/ leaf spot (Alternaria sesame) of sesame,sorghum rust (Puccinia purpurea) and Alternaria blight/ leaf spot (Alternaria cyamopsidis) of cluster beanwere noticed with 10 to 50% incidence.

Inheritance Pattern of A1 Cytoplasmic-nuclear Male Sterility System in Commercial Pearl Millet Hybrids [Pennisetum glaucum (L). R. Br.] in Summer and Post-rainy Seasons

Background: This study aimed to understand the genetic aspects and inheritance patterns that control the process of restoring fertility in the context of the A1 system of Cytoplasmic-Nuclear Male Sterility (CMS) in pearl millet. Methods: The experimentation was conducted in commercial pearl millet hybrids, utilizing three F2 populations and three BC1 populations. These populations underwent assessment during the rainy and post-rainy seasons at Rallis India Limited, Hyderabad During the Post-rainy (November-February) and summer (March-June) seasons of 2022-2023. Segregation data derived from observations on pollen shedding and seed set were gathered and subsequently, statistical analysis was performed. The Chi-square (χ2) test was employed to assess the conformity of the observed segregation data to the expected genetic ratios, thus evaluating the goodness of fit. Result: The hybrid combinations MP13P025A ×MP16P050R (MP7171) and MP18P069A × MP20P081R (MP7214) consistently displayed a 3:1 segregation ratio in the F2 generation and a 1:1 ratio in the BC1 generation, regardless of the rainy or post-rainy seasons. However, the cross between MP14030A and MP15P038R (MP7878) showed irregularities in both seasons due to modifiers and environmental factors. These irregularities stemmed from an excess of fertile plants (FF) in the post-rainy season or an excess of sterile plants (FS) in the summer season. These observations provide valuable insights into the genetic dynamics of the A1 Cytoplasmic-Nuclear Male Sterility (CMS) system within commercial pearl millet hybrids. The study indicates that fertility restoration in the A1-based CMS system is strongly influenced by a single Dominant gene control mechanism governing the interplay between male sterility and fertility restoration in these crosses.

Evaluation of nutritional composition, functional and pasting properties of pearl millet, teff, and buckwheat grain composite flour

Injera, bread, and other baked Ethiopian foods are typically made from a single cereal grain, which is insufficient to meet the nutritional requirements of all age groups. Enrichment of cereal with easily affordable cereals and pseudocereals that have superior nutritional value is an important approach to producing nutrient-dense food products. Therefore, this study aimed to evaluate the nutritional composition, phytochemical content, functional and pasting properties of teff, pearl millet, and buckwheat composite flour. The design used during the conducting of the experiment was a completely randomized design (CRD). The nutritional composition, functional and pasting properties of composite flour were determined using standard procedures. The resulting composite flour from the study contained protein of 8.59–9.94 %, crude fat of 3.70–5.40 %, crude fiber of 2.28–2.62 %, total ash of 1.86–2.28 %, carbohydrate of 71.80–74.90 % and energy of 367.24–375.88 kcal/100 g. The mineral content (mg/100 g) ranged from 8.64 to 11.12, 72.82–93.14, and 1.32–1.74 iron, calcium, and zinc, respectively. Functional properties of composite flours such as bulk density (BD), water absorption index (WAI), and water solubility index (WSI) ranged from 555.08 to 596.23 kg/m, 2.12–2.18 g/g and 6.63–7.00 % respectively. The highest and lowest total phenolic content values were observed in composite flour of 10 % pear millet,70 % teff, and 20 % buckwheat (110.42 mg GAE/100 g) and composite flour of 40 % pear millet,55 % teff, and 5 % buckwheat (101.42 mg GAE/100 g), respectively. The addition of pearl millet and buckwheat flours to teff flour significantly (p ˂ 0.05) increases the functional and pasting properties of composite flour. Pasting properties of composite flours contained peak viscosity ranging from 1454 to 2071cP, trough viscosity 619–883cP, breakdown viscosity 835–1188cP, setback viscosity 1127–1483cP, pasting temperature 73.77–75.10 °C, and peak time 5.22–5.27 min. Pearl millet, buckwheat, and teff are three gluten-free grains that are increasingly being used in industrial applications. Teff, pearl millet, and buckwheat composite flour are all high in nutrients, and they offer a variety of health benefits. Blending these three grains can create a nutritious and delicious product that is also gluten-free. This study found that composite flour made from 70 % teff, 20 % buckwheat, and 10 % pearl millet has improved nutritional properties and could be used to make healthier food products in the food industry.

Sensory Acceptability and Nutritional Attributes of Hummus Developed from Pearl Millet (Bajra) Microgreens

Microgreens are young, tender greens and are excellent source of vitamins, minerals, bioactive and health-supporting components. But they have shorter shelf life. Therefore, the present study was conducted to prepare hummus from Pearl Millet microgreens and to evaluate its sensory and nutritional attributes. Microgreen-based Hummus was prepared by chickpeas and microgreens blended in different ratios. All the ingredients used in making hummus were procured from the local market. Chickpeas were soaked in water overnight and then strained and boiled. Microgreens were grown in an indoor setup. Different variations of hummus were developed using chickpea and microgreens i.e. T1 (100:0), T2 (80:20), T3 (60:40) and T4 (40:60), respectively. The formulated hummus was subjected to sensory evaluation to test its acceptability using a 9- point Hedonic scale. Hummus developed with the incorporation of 60 per cent pearl millet microgreens (treatment T4) was most acceptable out of all treatments. The incorporation of microgreens in hummus can be done to deal with the issue of short shelf life of microgreens. Conversion of Microgreens into Hummus can be a solution to make it rich in phytochemicals, carotenoids and phenolic compounds.

Improving grain quality and nitrogen use efficiency of cereal-based cropping systems on vertisols in semi-arid tropics

ContextSemi-arid tropics is facing serious issues of malnutrition in population owing to poor quality of food grain production. Malnutrition is directly linked to lower grain protein and zinc yield due to inappropriate land and water, and nutrient management practices, which also resulted into reduced nitrogen use efficiency (NUE) in cereals. ObjectiveThe objectives of the study were to evaluate the effect of land and water and nutrient management on grain protein and zinc yield, and NUE of cereal-based cropping systems on vertisols soils in semi-arid tropics. MethodsThe study was carried out at Hyderabad in India during 2014–15 and 2015–16 and involved three cropping systems (two rotation systems: sorghum-chickpea and maize-groundnut; and one intercropping: pearl millet + pigeonpea), two land and water management i.e. flatbed and broad bed furrows and four nutrient management-N1: Control (no fertilizer), N2: 100% recommended application of macronutrient (nitrogen, phosphorus and potassium) through chemical fertilizer, N3: N2 + 100% recommended application of secondary nutrient (sulphur) and micronutrient (zinc and boron) through chemical fertilizer, and N4 (integrated nutrient): 50% of N2 + 50% nitrogen in cereals or phosphorus in legumes through organic fertilizer as vermicompost. ResultsIn sorghum-chickpea rotation system, the treatment interaction broad bed furrows with 100% recommended application of macronutrient, secondary nutrient and micronutrient recorded significantly higher grain zinc yield in both the years, while grain protein yield was significantly higher in second year. The grain protein and zinc yield in sorghum-chickpea rotation system, and agronomic nitrogen use efficiency in pearl millet+pigeonpea intercropping system was significantly higher in broad bed furrows than flatbed. The agronomic NUE of broad bed furrows was higher by 61% in 2014–15 and 65% in 2015–16 over flatbed. Among the nutrient management treatments, grain protein and zinc yield, and agronomic NUE were significantly higher in combined application of macronutrient, secondary nutrient, and micronutrients through chemical fertilizer i.e. N3 followed by N4, N2 and N1. ConclusionThe broad bed furrows and application of macronutrient, secondary nutrient and micronutrient could be an effective integrated land and water and nutrient management approach to improve grain quality and agronomic nitrogen use efficiency of cereal-based cropping systems in semi-arid tropics. ImplicationsThis study contributed to develop integrated land and water and nutrient management as an innovative agronomic management practice for cereal-based cropping systems, which needs to scale-up through Government agricultural policies to overcome the issue of malnutrition in population living in semi-arid tropics.

Evaluation of the potentials of <i>Pennisetium glaucum</i> and <i>Vigna unguiculata</i> for phytoremediation of Spent-engine oil contaminated soil

One promising technique for cleaning up soil polluted by spent engine oil is phytoremediation. Particularly in the tropics, where resources can be scarce and the climate is favorable for plant development. Finding plant species that will work well with this technology was the aim of this investigation. The ability of a cereal (Pennisetum glaucum) and a legume (Vigna unguiculata) to remediate soil contaminated with 1%, 2%, 3%, 4%, and 5% (W/V) of spent engine oil was evaluated. After 150 days of incubation, the Total Petroleum Hydrocarbon (TPH) loss in greenhouse studies was calculated. The total petroleum hydrocarbon content of soil that was vegetated with P. glaucum and V. unguiculata was substantially lower than that of non-vegetated soil. Furthermore, a positive association was discovered between the initial TPH and the total petroleum hydrocarbon loss caused by planting P. glaucum. It was also discovered that P. glaucum outperformed V. unguiculata in remediation capacity. These findings suggest that P. glaucum be investigated further, which might lead to a better understanding of how to apply phytoremediation to soils contaminated with spent-engine oil.

Management interventions of pearl millet systems for attaining cereal self-sufficiency in Senegal

Critical management interventions to target the yield potential for each environment are key to food security, increasing the resilience of current agricultural systems in Senegal. Cereal production is highly dependent on pearl millet (Pennisetum glaucum L.) rainfed systems as one of the major field crops for smallholders. This study aims to (i) quantify the production of pearl millet at the department level for the last quinquennial (until 2020), (ii) assess the impact of weather (temperature and precipitation) on the millet-based supply of cereal demand, and (iii) investigate, through crop modeling, the impact of millet-based supply of cereal demand by comparing recommended management interventions with smallholder-based strategies at the department level. Millet-based cereal supply–demand was estimated considering the observed population and the supply via the simulated pearl millet production (obtained using the APSIM-Millet model) at the department level from 1990 to 2021. High temperature and low precipitation occurrence presented a frequency of 35% across departments, leading to a reduction in millet production by roughly 6% relative to the normal average for 32 years. Adoption of recommended management showed the potential to increase the millet supply, more than doubling the current cereal supply, closing the current supply–demand gap (89 kg inhabitant−1). Achieving future cereal self-sufficiency will also require an intensification of other cereal production.

Effect of Seaweed Liquid Fertilizer on Sorghum bicolor and Pennisetum glaucum

Millets are small-seeded grasses belonging to the family Poaceae that help in human and animal nourishment. They are mostly grown by using chemical fertilizers which are depleting soil fertility. Organic fertilizers are eco-friendly and help to enhance the growth and development of plants thereby maintaining soil health. Seaweed liquid fertilizer (SLF) are organic fertilizers that can be used to control the side effects caused by harmful chemical fertilizers. The present study was carried out to check the effects of seaweed liquid fertilizer on the growth and development of millets. Different concentrations of seaweed liquid fertilizer (0.25%, 0.50%, and 0.75%) were prepared from Sargassum cinerum, Ulva intestinalis, and Padina tetrastromatica, which were tested on Sorghum bicolor and Pennisetum glaucum. Growth parameters like root length, shoot height, flowering-fruiting, and biochemical analysis like proteins were analyzed by using seaweed liquid fertilizer and chemical fertilizer. Plants treated with 0.50% concentration of seaweed liquid fertilizer showed higher protein content. Total chlorophyll was found to be higher in treated plants than in control plants. Flowering and fruiting were observed earlier in seaweed liquid fertilizer treated plants. This concludes that seaweed extracts can be used as a promising alternative to chemical fertilizers, which plays a significant role in the holistic growth enhancement of plants.

Screening pearl millet genotypes for resistance to Striga hermonthica and compatibility to Fusarium oxysporum f.sp. strigae

Pearl millet (Pennisetum glaucum [L.] R. Br., 2n = 2x = 14) is a nutritionally rich and climate-resilient food crop cultivated globally. It is a crucial staple crop in Burkina Faso and the dry Sahel region, encompassing Niger, Mali, and Senegal. However, the yield of pearl millet is relatively low in the region (<0.85 tons ha−1) due to Striga hermonthica (Sh) infestation, bird damage, insect pests, diseases, and low-yielding open-pollinated landrace varieties. The study aimed to screen genetically diverse pearl millet accessions for Sh resistance and compatibility to a Striga bio-control agent, Fusarium oxysporum f. sp. Strigae (FOS), to select contrasting and promising parents for resistance breeding and production. One hundred and fifty genotypes were evaluated in Sh hotspot fields in the rain-fed and greenhouse conditions using an alpha lattice design and two replications in Burkina Faso. Significant differences were recorded among the tested pearl millet genotypes for the assessed agro-morphological and Striga resistance. Days to flowering was significantly delayed in the assessed genotypes due to Sh infestation. Applying FOS on pearl millet seed significantly reduced the mean Striga number in Sh-infested conditions. The following genotypes: IP-3098, IP-6112, IP-9242, IP-10579, and IP-11358 were identified as exhibiting Sh resistance and were compatible to FOS. The pearl millet genotypes supported few to none Sh emerged plants with comparatively low values under the Striga number progress curve. The selected genotypes are useful parents to breed for Striga resistance and integrated management in Burkina Faso and related agroecologies.

Unraveling the interplay between root exudates, microbiota, and rhizosheath formation in pearl millet

BackgroundThe rhizosheath, a cohesive soil layer firmly adhering to plant roots, plays a vital role in facilitating water and mineral uptake. In pearl millet, rhizosheath formation is genetically controlled and influenced by root exudates. Here, we investigated the impact of root exudates on the microbiota composition, interactions, and assembly processes, and rhizosheath structure in pearl millet using four distinct lines with contrasting soil aggregation abilities.ResultsUtilizing 16S rRNA gene and ITS metabarcoding for microbiota profiling, coupled with FTICR-MS metabonomic analysis of metabolite composition in distinct plant compartments and root exudates, we revealed substantial disparities in microbial diversity and interaction networks. The ß-NTI analysis highlighted bacterial rhizosphere turnover driven primarily by deterministic processes, showcasing prevalent homogeneous selection in root tissue (RT) and root-adhering soil (RAS). Conversely, fungal communities were more influenced by stochastic processes. In bulk soil assembly, a combination of deterministic and stochastic mechanisms shapes composition, with deterministic factors exerting a more pronounced role. Metabolic profiles across shoots, RT, and RAS in different pearl millet lines mirrored their soil aggregation levels, emphasizing the impact of inherent plant traits on microbiota composition and unique metabolic profiles in RT and exudates. Notably, exclusive presence of antimicrobial compounds, including DIMBOA and H-DIMBOA, emerged in root exudates and RT of low aggregation lines.ConclusionsThis research underscores the pivotal influence of root exudates in shaping the root-associated microbiota composition across pearl millet lines, entwined with their soil aggregation capacities. These findings underscore the interconnectedness of root exudates and microbiota, which jointly shape rhizosheath structure, deepening insights into soil–plant-microbe interactions and ecological processes shaping rhizosphere microbial communities. Deciphering plant–microbe interactions and their contribution to soil aggregation and microbiota dynamics holds promise for the advancement of sustainable agricultural strategies.46mkfZGLAk7WD-UFCK_cLiVideo

Combined exposure of PVC-microplastic and mercury chloride (HgCl2) in sorghum (Pennisetum glaucum L.) when its seeds are primed titanium dioxide nanoparticles (TiO2-NPs).

The present work studied the impact of different levels of PVC-microplastics (PVC-MPs), namely 0 (no PVC-MPs), 2, and 4mg L-1, along with mercury (Hg) levels of 0 (no Hg), 10, and 25mgkg-1 in the soil, while concurrently applying titanium dioxide-nanoparticles (TiO2-NPs) at 0 (no TiO2-NPs), 50, and 100µgmL-1 to sorghum (Pennisetum glaucum L.) plants. This study aimed to examine plant growth and biomass, photosynthetic pigments and gas exchange characteristics, oxidative stress indicators, and the response of various antioxidants (enzymatic and non-enzymatic) and their specific gene expression, proline metabolism, the AsA-GSH cycle, and cellular fractionation in the plants. The research outcomes indicated that elevated levels of PVC-MPs and Hg stress in the soil notably reduced plant growth and biomass, photosynthetic pigments, and gas exchange attributes. However, PVC-MPs and Hg stress also induced oxidative stress in the roots and shoots of the plants by increasing malondialdehyde (MDA), hydrogen peroxide (H2O2), and electrolyte leakage (EL) which also induced increased compounds of various enzymatic and non-enzymatic antioxidants and also the gene expression and sugar content. Furthermore, a significant increase in proline metabolism, the AsA-GSH cycle, and the pigmentation of cellular components was observed. Although, the application of TiO2-NPs showed a significant increase in plant growth and biomass, gas exchange characteristics, enzymatic and non-enzymatic compounds, and their gene expression and also decreased oxidative stress. In addition, the application of TiO2-NPs enhanced cellular fractionation and decreased the proline metabolism and AsA-GSH cycle in P. glaucum plants. These results open new insights for sustainable agriculture practices and hold immense promise in addressing the pressing challenges of heavy metal contamination in agricultural soils.

Three years of cover crops management increased soil organic matter and labile carbon pools in a subtropical vegetable agroecosystem

AbstractCover crops have been widely adopted to improve soil functions in agroecosystems, including providing carbon (C) inputs that can contribute to soil C sequestration. However, soil C changes may be slow after introducing cover crops in unfavorable environments for soil organic matter (SOM) accumulation, like the Southeast United States subtropical region characterized by a warm humid climate, and coarse‐textured soils. We examined labile C pools as potential early indicators of SOM changes after cover crop introduction in a sandy subtropical vegetable production system. We compared the effects of four cover crop monocultures namely two grasses [sorghum sudangrass, Sorghum bicolor × S bicolor var. Sudanese and pearl millet, Pennisetum glaucum (L.) R. Br.], two legumes (sunn hemp, Crotalaria juncea L., and cowpea, Vigna unguiculata Walp.), and one four‐species mixture on soil organic carbon pools for 3 years. Soil samples were collected at a 15‐cm depth before cover crop planting and post cover crop incorporation to assess changes in SOM, permanganate‐oxidizable carbon (POX‐C), mineralizable carbon (Cmin), and water extractable organic carbon (WEOC). The incorporation of cover crops increased concentrations of SOM, POX‐C, and Cmin in year 3 relative to their baseline values in year 1. Concentration of SOM increased by 0.24 ± 0.05% (mean ± standard error) after 3 years of cover crop management. However, concentrations of WEOC significantly decreased in years 2 and 3 relative to the baseline. Monocultures and the mixture had similar effects on measured C pools, likely due to comparable aboveground biomass production. Our findings highlight the potential of POX‐C and Cmin as early indicators of SOM accumulation driven by cover crops use, as well as the capacity of cover crops to build SOM in similar subtropical systems and coarser textured soils.

Abiotic stress tolerance in pearl millet: Unraveling molecular mechanisms via transcriptomics.

Pearl millet (Pennisetum glaucum (L.)) is a vital cereal crop renowned for its ability to thrive in challenging environmental conditions; however, the molecular mechanisms governing its salt stress tolerance remain poorly understood. To address this gap, next-generation RNA sequencing was conducted to compare gene expression patterns in pearl millet seedlings exposed to salt stress with those grown under normal conditions. Our RNA sequencing analysis focused on shoots from 13-day-old pearl millet plants subjected to either salinity stress (150 mmol of NaCl for 3 days) or thermal stress (50°C for 60 s). Of 36,041 genes examined, 17,271 genes with fold changes ranging from 2.2 to 19.6 were successfully identified. Specifically, 2388 genes were differentially upregulated in response to heat stress, whereas 4327 genes were downregulated. Under salt stress conditions, 2013 genes were upregulated and 4221 genes were downregulated. Transcriptomic analysis revealed four common abiotic KEGG pathways that play crucial roles in the response of pearl millet to salt and heat stress: phenylpropanoid biosynthesis, photosynthesis-antenna proteins, photosynthesis, and plant hormone signal transduction. These metabolic pathways are necessary for pearl millet to withstand and adapt to abiotic stresses caused by salt and heat. Moreover, the pearl millet shoot heat stress group showed specific transcriptomics related to KEEG metabolic pathways such as cytochrome P450, cutin, suberine, and wax biosynthesis, zeatin biosynthesis, crocin biosynthesis, ginsenoside biosynthesis, saponin biosynthesis, and biosynthesis of various plant secondary metabolites. In contrast, pearl millet shoots exposed to salinity stress exhibited transcriptomic changes associated with KEEG metabolic pathways related to carbon fixation in photosynthetic organisms, mismatch repair, and nitrogen metabolism. Our findings underscore the remarkable cross-tolerance of pearl millet to simultaneous salt and heat stress, elucidated through the activation of shared abiotic KEGG pathways. This study emphasizes the pivotal role of transcriptomics analysis in unraveling the molecular responses of pearl millet under abiotic stress conditions.

Comprehensive analysis of B3 family genes in pearl millet (Pennisetum glaucum) and the negative regulator role of PgRAV-04 in drought tolerance.

Members of the plant-specific B3 transcription factor superfamily play crucial roles in various plant growth and developmental processes. Despite numerous valuable studies on B3 genes in other species, little is known about the B3 superfamily in pearl millet. Here, through comparative genomic analysis, we identified 70 B3 proteins in pearl millet and categorized them into four subfamilies based on phylogenetic affiliations: ARF, RAV, LAV, and REM. We also mapped the chromosomal locations of these proteins and analyzed their gene structures, conserved motifs, and gene duplication events, providing new insights into their potential functional interactions. Using transcriptomic sequencing and real-time quantitative PCR, we determined that most PgB3 genes exhibit upregulated expression under drought and high-temperature stresses, indicating their involvement in stress response regulation. To delve deeper into the abiotic stress roles of the B3 family, we focused on a specific gene within the RAV subfamily, PgRAV-04, cloning it and overexpressing it in tobacco. PgRAV-04 overexpression led to increased drought sensitivity in the transgenic plants due to decreased proline levels and peroxidase activity. This study not only adds to the existing body of knowledge on the B3 family's characteristics but also advances our functional understanding of the PgB3 genes in pearl millet, reinforcing the significance of these factors in stress adaptation mechanisms.

Transpiration efficiency variations in the pearl millet reference collection PMiGAP.

Transpiration efficiency (TE), the biomass produced per unit of water transpired, is a key trait for crop performance under limited water. As water becomes scarce, increasing TE would contribute to increase crop drought tolerance. This study is a first step to explore pearl millet genotypic variability for TE on a large and representative diversity panel. We analyzed TE on 537 pearl millet genotypes, including inbred lines, test-cross hybrids, and hybrids bred for different agroecological zones. Three lysimeter trials were conducted in 2012, 2013 and 2015, to assess TE both under well-watered and terminal-water stress conditions. We recorded grain yield to assess its relationship with TE. Up to two-fold variation for TE was observed over the accessions used. Mean TE varied between inbred and testcross hybrids, across years and was slightly higher under water stress. TE also differed among hybrids developed for three agroecological zones, being higher in hybrids bred for the wetter zone, underlining the importance of selecting germplasm according to the target area. Environmental conditions triggered large Genotype x Environment (GxE) interactions, although TE showed some high heritability. Transpiration efficiency was the second contributor to grain yield after harvest index, highlighting the importance of integrating it into pearl millet breeding programs. Future research on TE in pearl millet should focus (i) on investigating the causes of its plasticity i.e. the GxE interaction (ii) on studying its genetic basis and its association with other important physiological traits.

Cover crop diversity for sustainable agriculture: Insights from the Cerrado biome

AbstractBrazil is one of the largest soybean producer of the world and the Cerrado biome has played a pivotal role in this expansion. Because of the economic and agronomic challenges associated with the maize production as a second summer crop in this region, cover crops are gaining popularity as a strategy to diversify the agricultural system while enhancing soil health. This study assessed the benefits of single species of cover crops and a mix of cover crop species in between harvest seasons to the soybean grain yield and nematode suppression. The study was carried out for 3 years in two locations within the Cerrado biome. We evaluated six cover crop treatments after soybean cultivation: (1) Mix of cover crops (Pennisetum glaucum, Crotalaria spectabilis and Urochloa ruziziensis), (2) P. glaucum (Pearl millet), (3) C. spectabilis, (4) U. ruziziensis (Congo grass) (5) Urochloa brizantha cv. Marandu (Marandu palisadegrass) and (6) U. brizantha BRS Paiaguás (Paiaguás palisadegrass). Pennisetum glaucum and U. brizantha cv. Marandu produced highest amounts of biomass on a 3‐year average. In one site, P. glaucum produced more biomass than other cover crops by 210%. Tropical grasses (U. ruziziensis, Marandu and Paiaguás), along with the cover crop mixture, exhibited intermediate biomass levels in the site with higher P. glaucum biomass production and did not differ from P. glaucum in the other site. Cover crops varied nutrient uptake depending on the species. Decomposition rates varied among cover crops as expected, with C. spectabilis decomposing rapidly and releasing substantial amounts nutrients, particularly nitrogen. In contrast, the cover crop mixture had a slower decomposition. The choice of cover crop significantly influenced soybean population and yield, with some variability across years and locations. The cover crop mixture consistently supported higher soybean populations and yields, highlighting its potential for enhancing soybean production, nutrient cycling and nematode suppression. It effectively reduced nematode abundance in soybean roots, highlighting its role in nematode management. Our findings emphasize the robustness and versatility of cover crop mixtures in mitigating weather variability across years and sites. They consistently performed well in terms of biomass production, nutrient uptake, soybean yields and nematode control. This study highlights the vital role of cover crops in the Cerrado ecosystem, enhancing soil health, crop productivity and environmental sustainability. The choice of cover crop species and mixtures offers a valuable tool for farmers seeking resilient and sustainable agricultural practices amid changing environmental conditions.

Sobressemeadura de pastos anuais de verão na cultura da soja para suprir a escassez de foragem outonal

ABSTRACT: In integrated crop-livestock systems, overseeding annual summer pastures over grain crops can reduce forage shortages in autumn without altering grain production. This study evaluated the influence of pearl millet (Pennisetumglaucum L.) and sudangrass (Sorghum Sudanese) overseeded on a soybean (Glycine Max) crop or no-tillage seeding after soybean harvest on productive aspects of pasture. The experimental design was a randomized block with treatments in a 2 × 2 factorial arrangement (pearl millet or sudangrass, overseeding in the full seed stage (R6) of soybean crops or seeding them in a no-tillage system after soybean harvest) in two agricultural years. Pasture height, plant stand, tiller density, and forage production were higher in the first crop year. The overseeding strategy resulted in higher pasture height and foraged production in the first crop year and higher pasture utilization for the next two crop years. Under the no-tillage strategy, the plants stand more elevated in the first crop year, resulting in a higher tiller density in the second crop year. Pasture height, utilization period, and forage production did not differ among the forage species. Pearl millet had a more elevated plant stand, while sudangrass had a higher tiller density. Annual summer pasture overseeding of soybean crops increases the pasture utilization period and forage production in autumn.