Significant Yield Research Articles

Mitogen-activated protein kinases MPK3 and MPK6 phosphorylate receptor-like cytoplasmic kinase CDL1 to regulate soybean basal immunity.

Soybean cyst nematode (SCN; Heterodera glycines Ichinohe), one of the most devastating soybean (Glycine max) pathogens, causes significant yield loss in soybean production. Nematode infection triggers plant defense responses; however, the components involved in the upstream signaling cascade remain largely unknown. In this study, we established that a mitogen-activated protein kinase (MAPK) signaling module, activated by nematode infection or wounding, is crucial for soybeans to establish SCN resistance. GmMPK3 and GmMPK6 directly interact with CDG1-LIKE1 (GmCDL1), a member of the receptor-like cytoplasmic kinase (RLCK) subfamily VII. These kinases phosphorylate GmCDL1 at Thr-372 to prevent its proteasome-mediated degradation. Functional analysis demonstrated that GmCDL1 positively regulates immune responses and promotes SCN resistance in soybeans. GmMPK3-mediated and GmMPK6-mediated phosphorylation of GmCDL1 enhances GmMPK3 and GmMPK6 activation and soybean disease resistance, representing a positive feedback mechanism. Additionally, 2 L-type lectin receptor kinases, GmLecRK02g and GmLecRK08g, associate with GmCDL1 to initiate downstream immune signaling. Notably, our study also unveils the potential involvement of GmLecRKs and GmCDL1 in countering other soybean pathogens beyond nematodes. Taken together, our findings reveal the pivotal role of the GmLecRKs-GmCDL1-MAPK regulatory module in triggering soybean basal immune responses.

Pathogenicity of Puccinia striiformis f. sp. tritici and quantitative traits on bread wheat landraces in Ethiopia

AbstractBread wheat (Triticum aestivum L.) is severely affected by stripe rust caused by Puccinia striiformis Westend. f. sp. tritici (Pst). This study was conducted to investigate pathogenicity of Pst isolates to bread wheat landraces grown in Ethiopia, establish stripe rust yield loss models and estimate variability in bread wheat quantitative traits. A greenhouse pot experiment was setup to assess seedling stage responses of landraces to Pst and a field study was conducted for adult plant stage evaluation. Among dominant isolates of Pst, Kubsa was the most virulent. Apart from the detection of resistance at the seedling stage study, a broad range of adult‐stage resistance was also observed which can confer durable resistance. Among single‐point models, the onset of severe infection at the development of heading stage causes significant yield loss by stripe rust. The integral yield loss model predicted a strong negative linear relationship between agronomic traits and stripe rust. Hierarchical analysis revealed the presence of three distinct clusters of bread wheat landraces, each forming different stripe rust resistance groups. With the exception of the harvest index and the growth stage parameter of days to heading, all agronomic traits were significantly different for the various landraces. This suggests the presence of diverse genetic resources, which might have also led to different responses to the stripe rust in these materials. This work clarifies the many ways in which landraces of bread wheat react to Pst infection, revealing a range of resistance mechanisms that can be used for efficient disease management.

A novel QTL conferring Fusarium crown rot resistance on chromosome 2A in a wheat EMS mutant.

A novel QTL on chromosome 2A for Fusarium crown rot resistance was identified and validated in wheat. Fusarium crown rot (FCR) is a fungal disease that causes significant yield losses in many cereal growing regions in the world. In this study, genetic analysis was conducted for a wheat EMS mutant C549 which showed stable resistance to FCR at seedling stage. A total of 10 QTL were detected on chromosomes 1A, 2A, 3B, 4A, 6B, and 7B using a population of 138 F7 recombinant inbred lines (RILs) derived from a cross between C549 and a Chinese germplasm 3642. A novel locus Qfcr.cau-2A, which accounted for up to 24.42% of the phenotypic variation with a LOD value of 12.78, was consistently detected across all six trials conducted. Furthermore, possible effects of heading date (HD) and plant height on FCR severity were also investigated in the mapping population. While plant height had no effects on FCR resistance, a weak and negative association between FCR resistance and HD was observed. A QTL for HD (Qhd.cau-2A.2) was coincident with Qfcr.cau-2A. Conditional QTL mapping indicated that although Qfcr.cau-2A and Qhd.cau-2A.2 had significant interactions, Qfcr.cau-2A remained significant after the effects of HD was removed. It is unlikely that genes underlying these two loci are same. Nevertheless, the stable expression of Qfcr.cau-2A in the validation population of 148 F7 RILs developed between C549 and its wild parent Chuannong 16 demonstrated the potential value of this locus in FCR resistance breeding programs.

Exploring the efficacy of a Trichoderma asperellum-based seed treatment for controlling Fusarium equiseti in chickpea

BackgroundChickpea plant (Cicer arietinum L.) is an important legume crop that is vulnerable to various fungal pathogens causing significant yield losses. Among them, Fusarium equiseti is a pathogen that has started to raise concern. In contrast, Trichoderma species have been explored for their ability to control such pathogens. In this study, the efficacy of a novel seed treatment formulation was explored for controlling F. equiseti in chickpea plants. The formulation was designated to enhance growth in chickpea plants as well as the ability to protect plants from infection. In addition, this formulation was tested for its effectiveness in maintaining the conidia of the antagonist in the soil after sowing.ResultsApplying the Trichoderma asperellum-based formulation promoted growth, as well as root and aerial biomass. In seedlings derived from treated seeds, the shoot length increased by 36.8%, and the average number of leaves also increased than the control. Following evaluation of disease severity and the foliar alteration index (FAI), a protective effect was noted, as the symptoms of Fusarium were significantly reduced in treated plants than the infected control. Re-isolation from plants infected with F. equiseti was successful in the roots (72.7%), root crown (84.5%), stem (64.4%), and even in petioles (36.1%).ConclusionsDue to both direct antagonist activity and indirect growth promotion ability, the findings suggested that tested formulation can be a sustainable and eco-friendly alternative to chemical fungicides for managing F. equiseti in chickpea seeds.

Raman developmental markers in root cell walls are associated with lodging tendency in tef

Main conclusionUsing Raman micro-spectroscopy on tef roots, we could monitor cell wall maturation in lines with varied genetic lodging tendency. We describe the developing cell wall composition in root endodermis and cylinder tissue.Tef [Eragrostis tef (Zucc.) Trotter] is an important staple crop in Ethiopia and Eritrea, producing gluten-free and protein-rich grains. However, this crop is not adapted to modern farming practices due to high lodging susceptibility, which prevents the application of mechanical harvest. Lodging describes the displacement of roots (root lodging) or fracture of culms (stem lodging), forcing plants to bend or fall from their vertical position, causing significant yield losses. In this study, we aimed to understand the microstructural properties of crown roots, underlining tef tolerance/susceptibility to lodging. We analyzed plants at 5 and 10 weeks after emergence and compared trellised to lodged plants. Root cross sections from different tef genotypes were characterized by scanning electron microscopy, micro-computed tomography, and Raman micro-spectroscopy. Lodging susceptible genotypes exhibited early tissue maturation, including developed aerenchyma, intensive lignification, and lignin with high levels of crosslinks. A comparison between trellised and lodged plants suggested that lodging itself does not affect the histology of root tissue. Furthermore, cell wall composition along plant maturation was typical to each of the tested genotypes independently of trellising. Our results suggest that it is possible to select lines that exhibit slow maturation of crown roots. Such lines are predicted to show reduction in lodging and facilitate mechanical harvest.

Improving TB Case Detection Through Active Case-Finding: Results of Multiple Intervention Strategies in Hard-to-Reach Riverine Areas of Southern Nigeria.

A major challenge to TB control globally is low case detection, largely due to routine health facility-based passive case-finding employed by national TB control programs. Active case-finding is a risk-population-based screening approach that has been established to be effective in TB control. This intervention aimed to increase TB case detection in hard-to-reach areas in southern Nigeria. Using a descriptive cross-sectional design, we conducted implementation research in 15 hard-to-reach riverine local government areas with historically recognized low TB case notification rates. Individuals with TB symptoms were screened using multiple strategies. Data were collected quarterly over a 4-year period using reporting tools and checklists. Descriptive analysis was done with Microsoft Excel spreadsheet 2019. A total of 1,089,129 individuals were screened: 16,576 in 2017; 108,102 in 2018; 697,165 in 2019; and 267,286 in 2020. Of those screened, 24,802 (2.3%) were identified as presumptive TB, of which 88.8% were tested and 10% were diagnosed with TB (0.23% of those screened). TB notifications more than doubled, increasing by 183.3% and 137.5% in the initial implementation and scale-up, respectively. On average, 441 individuals needed to be screened to diagnose 1 TB case. The cases, predominantly males (56.1%) and aged 15 years and older (77.4%), comprised 71.9% bacteriologically confirmed drug-sensitive TB, 25.8% clinically diagnosed drug-sensitive TB, and 2.3% drug-resistant cases. Detection sources included community outreach (1,786), health facilities (505), people living with HIV (57), and household contacts of bacteriologically confirmed TB cases (123). Remarkably, 98.1% of diagnosed TB cases commenced treatment. We found a significant yield in TB case notifications, more than doubling the baseline figures. Given these successful results, we recommend prioritizing resources to support active case-finding strategies in national programs, especially in hard-to-reach areas with high-risk populations, to address TB more comprehensively.

Effect of <i>Dactyladenia barteri</i> mulch and NPK fertilizer on weed density, ginger production and soil recapitalization in Umudike, Southeast Nigeria

A field study conducted on a Gleyic Luvisol in Umudike, southeastern Nigeria, in 2017 and 2018 evaluated the effect of Dactyladenia barteri mulch and NPK fertilizer 15:15:15 on weed density, ginger production and soil health. Treatment consisted of three levels of mulch (0, 2 and 4 t ha–1) and two levels of NPK fertilizer (0.00 and 400 kg ha−1) laid in a randomized complete block design with 3 replicates on 2 x 2 m plots, using 0.20 x 0.20 m spacing. Planting was done in May each year and harvested eight months after planting. Results showed that control plot had 187.80 higher significant weed density than 2 and 4 t ha–1 mulch (88.20 and 81.80), respectively. Fertilizer had no significant effect on weed density. Ginger survival at 2.00 and 4.00 t ha–1 mulch (94.40 and 96%) differed significantly from the control plot (42.20%). Number of tillers in mulched plots (t ha–1) followed the order: 4 > 2 > 0 in both years. Fertilizer rate at 400 kg ha–1 gave higher significant rhizome yield more than 0 kg ha–1 in both years. Mulch at 4 t ha–1 increased soil pH by 12% relative to 7.94% increase by NPK fertilizer. Total N, available P and exchangeable K were increased by 12.30, 64.30 and 14.30% respectively, by mulch at 4 t ha–1, while NPK fertilizer increased total N, available P and exchangeable K by 5.60, 31.40 and 9.38%, respectively. It was concluded that application of Dactyladenia barteri mulch and NPK fertilizer reduced weed density, improved ginger production and recapitalized soil in Umudike, southeastern, Nigeria.

Does no-till crop management mitigate gaseous emissions and reduce yield disparities: An empirical US-China evaluation

Global agricultural systems face one of the greatest sustainability challenges: meeting the growing demand for food without leaving a negative environmental footprint. United States (US) and China are the two largest economies and account for 39 % of total global greenhouse gases (GHG) emissions into the atmosphere. No-till is a promising land management option that allows agriculture to better adapt and mitigate climate change effects compared to traditional tillage. However, the efficacy of no-till for mitigating GHG is still debatable. In this meta-analysis, we comprehensively assess the impact of no-till (relative to traditional tillage) on GHG mitigation potential and crop productivity in different agroecological systems and management regimes in the US and China. Overall, no-till in China did not change crop yields, although soil CO2 (8 %) and N2O (12 %) emissions decreased significantly, while soil CH4 emissions increased by 12 %. In contrast to Chinese no-till, a significant improvement in crop yields (up to 12 %) was recorded on US cropland under no-till. Moreover, significant decreases in soil N2O (21 %) and CH4 (12 %) emissions were observed. Of the three cropping systems, only wheat showed significant reduction in CO2, N2O and CH4 emissions in the Chinese no-till system. In the case of US, no-till soybean-rice and maize cropping systems demonstrated significant emission reductions for N2O and CO2, respectively. Interestingly, yields of no-till maize in China and rice in US exceeded those of other no-till cereals. In China, no-till on medium-texture soils resulted in significant reductions in GHG emissions and higher crop yields compared to other soil types. In both countries, the relatively higher crop yields under irrigated versus non-irrigated no-till and the significant yield differences on fine textured soils under US no-till are likely due to the substantial N2O reductions. In summary, crop yield disparities from no-till between China and the US were related to the insignificant effects on controlling CH4 emissions and successfully mitigating N2O, respectively. This study comprehensively demonstrates how cropping system and pedoclimatic conditions influence the relative effectiveness of no-till in both countries.

Impact of biochar from different agricultural wastes on soil chemical characteristics and growth of maize

The use of biochar as soil amendment is gaining acceptance as an important management strategy to tackle food insecurity for the growing population in Nigeria amid soil deterioration. This study examined the influence of biochar produced from the different agricultural wastes on soil chemical characteristics and growth of maize. A pot experiment was conducted at the greenhouse of Imo State University Owerri, Nigeria. The experiment was laid out in completely randomized design. The agricultural wastes used were rice husk, corn cob, poultry manure and pig dung. The agricultural wastes were charred differently for 60 minutes at the temperature of 250oC. The maize plant used for the experiment was Oba super II. The biochar was produced using modified biochar kiln and were applied to the soil at the rate of 10t ha-1. The treatments were replicated thrice. Soil amended with poultry manure charred for 60 minutes at 250oC (PMB60) had the highest significant growth (plant height) and yield (dry matter) parameters. Significant differences were observed among the biochar amendments with the soil chemical characteristics (pH, Available P, SOM, TN, Exchangeable base cations and CEC). However, the study reported that PMB60 gave the highest significant increase in almost all the soil chemical characteristics (soil pH(6.0), Avail. P(18.20mg kg-1), exchangeable Ca(5.8Cmol kg-1), Mg(3.97Cmol kg-1, K(0.32Cmol kg-1, Na(0.28Cmol kg-1) and CEC(10.75Cmol kg-1)) compared to the other biochar amendments. This study concluded that PMB60 was better suited to improve soil chemical characteristics while also improving maize performance compared to the other biochar amendments.

Does supplemental irrigation enhance smallholder monsoon season rice yield? Evidence from Bangladesh

AbstractIrrigation is one pillar of the Green Revolution that drove dramatic agricultural productivity gains across Asia. In Bangladesh, irrigation uptake has been so significant that 97% of dry‐season rice is now irrigated. While most Bangladesh monsoon rice is completely rainfed, supplementary irrigation is sometimes employed where late monsoon onset is potentially yield‐limiting. Station‐controlled experiments provide a narrative of positive yield benefits from supplementary irrigation. In contrast, statistical evaluations of actual farm experience mostly show no yield benefit and lower profitability for supplementary irrigation adopters. To add evidence on this controversial practice, we evaluated data from 2012 and 2015 Bangladesh farm household surveys with causality econometric approaches that control for differences between supplementary irrigation adopter and non‐adopter groups. After controlling for self‐selection and endogeneity, we found no statistically significant yield benefit for supplementary irrigation. Our results support scepticism about the profitability of supplementary irrigation. As such, we recommend careful consideration of the mixed evidence on effectiveness in future supplementary irrigation project benefit cost analyses. Further evidence over a longer time and accounting for a broader range of crops is also important moving forward.

Soil buffering capacity enhances maize yield resilience amidst climate perturbations

CONTEXTMaize production in China is facing a multitude of challenges such as climate change, increasing demand, and limited cropland availability. Soil properties, beyond supporting crop growth and development, can play a critical role in buffering the impacts of climate crisis on crop yields. However, little information is known about such buffering capacities and their spatial distributions of soil properties in buffering the impacts of climate perturbations on maize yields in China's maize belt (CMB). OBJECTIVEThe objective of this study was to identify the responses of different regions within the CMB to climate perturbations in terms of maize yields, as well as their spatial differences and magnitudes. Additionally, we aimed to quantify the capacities of soil properties in buffering the impacts of climate perturbations. METHODSWe quantified the impacts of climate perturbations (climate fluctuations deviating from the mean state) on maize yields using the APSIM across the China's maize belt. We then used the random forest model to interpret the buffering effects of typical soil properties to the adverse impacts of climate perturbations. RESULTS AND CONCLUSIONSOur results reveal that temperature variability was the predominant climatic perturbation affecting maize yields, with rising temperature leading to significant yield losses in most regions. Perturbations in solar radiation and precipitation exhibited relatively stronger positive yield impacts only in areas with inadequate solar radiation and dry conditions, respectively. Notably, soil properties explained ∼40% to ∼70% of the spatial variations for the impacts of climate perturbations. Soils with high soil organic carbon content (SOC) can significantly reduce the negative impacts of temperature increase, highlighting the crucial buffering effect of SOC in response to global warming. Soil texture, field capacity and bulk density were also critical soil buffering properties for interpreting the spatial patterns of the impacts of climate perturbations. SIGNIFICANCEOur results underscore the importance of soil quality improvement to ensure stable food production, which is an effective strategy for enhancing agricultural system resilience amidst future climate crises.

Diagnostic utility and reporting recommendations for clinical DNA methylation episignature testing in genetically undiagnosed rare diseases

PurposeThis study aims to assess the diagnostic utility and provide reporting recommendations for clinical DNA methylation episignature testing based on the cohort of patients tested through the EpiSign Clinical Testing Network. MethodsThe EpiSign assay utilized unsupervised clustering techniques and a support vector machine–based classification algorithm to compare each patient’s genome-wide DNA methylation profile with the EpiSign Knowledge Database, yielding the result that was reported. An international working group, representing distinct EpiSign Clinical Testing Network health jurisdictions, collaborated to establish recommendations for interpretation and reporting of episignature testing. ResultsAmong 2399 cases analyzed, 1667 cases underwent a comprehensive screen of validated episignatures, imprinting, and promoter regions, resulting in 18.7% (312/1667) positive reports. The remaining 732 referrals underwent targeted episignature analysis for assessment of sequence or copy-number variants (CNVs) of uncertain significance or for assessment of clinical diagnoses without confirmed molecular findings, and 32.4% (237/732) were positive. Cases with detailed clinical information were highlighted to describe various utility scenarios for episignature testing. ConclusionClinical DNA methylation testing including episignatures, imprinting, and promoter analysis provided by an integrated network of clinical laboratories enables test standardization and demonstrates significant diagnostic yield and clinical utility beyond DNA sequence analysis in rare diseases.

Resistance risk, resistance mechanism and the effect on DON production of a new SDHI fungicide cyclobutrifluram in Fusarium graminearum

Fusarium head blight in wheat is caused by Fusarium graminearum, resulting in significant yield losses and grain contamination with deoxynivalenol (DON), which poses a potential threat to animal health. Cyclobutrifluram, a newly developed succinate dehydrogenase inhibitor, has shown excellent inhibition of Fusarium spp. However, the resistance risk of F. graminearum to cyclobutrifluram and the molecular mechanism of resistance have not been determined. In this study, we established the average EC50 of a range of F. graminearum isolates to cyclobutrifluram to be 0.0110 μg/mL. Six cyclobutrifluram-resistant mutants were obtained using fungicide adaptation. All mutants exhibited impaired fitness relative to their parental isolates. This was evident from measurements of mycelial growth, conidiation, conidial germination, virulence, and DON production. Interestingly, cyclobutrifluram did not seem to affect the DON production of either the sensitive isolates or the resistant mutants. Furthermore, a positive cross-resistance was observed between cyclobutrifluram and pydiflumetofen. These findings suggest that F. graminearum carries a moderate to high risk of developing resistance to cyclobutrifluram. Additionally, point mutations H248Y in FgSdhB and A73V in FgSdhC1 of F. graminearum were observed in the cyclobutrifluram-resistant mutants. Finally, an overexpression transformation assay and molecular docking indicated that FgSdhBH248Y or FgSdhC1A73V could confer resistance of F. graminearum to cyclobutrifluram.

In vitro Evaluation of Antagonistic Effect of Bio Control Agents (BCA) against Mango Dieback Incited by Lasiodiplodia theobromae (Pat.) Griffon & Maubl

Mango (Mangifera indica L.) is one of the most important tropical fruit crops, belongs to family anacardiaceae. Mango is infected by number of diseases at all stages of its development, among them dieback caused by Lasiodiplodia theobromae (Pat.) Griffon & Maubl. is considered to be the most destructive disease, leading to significant yield loss and low fruit quality of mango due to slowly wilting of tree. The present investigation was carried out to evaluate the inhibitory activity of different bio-control agents (BCA) against L. theobromae. Different bioagents viz., Trichoderma viride NAU isolate, T. harzianum, NAU isolate, Pseudomonas fluorescens NAU isolate, Bacillus subtilis NAU isolate and Rhizospheric actinobacteria were tested by dual culture technique. Among them, highest per cent growth inhibition was found in T. viride (71.47%) followed by T. harzianum (67.15%) and rhizospheric actinobacteria (47.84%). P. fluorescens (3.46%) was found least effective against pathogen. The results indicated that among all the BCA, T. viride was most effective against L. theobromae. Hence, it can be explored further for management of mango dieback.

Genetic gains in early maturing maize hybrids developed by the International Maize and Wheat Improvement Center in Southern Africa during 2000-2018.

Genetic gain estimation in a breeding program provides an opportunity to monitor breeding efficiency and genetic progress over a specific period. The present study was conducted to (i) assess the genetic gains in grain yield of the early maturing maize hybrids developed by the International Maize and Wheat Improvement Center (CIMMYT) Southern African breeding program during the period 2000-2018 and (ii) identify key agronomic traits contributing to the yield gains under various management conditions. Seventy-two early maturing hybrids developed by CIMMYT and three commercial checks were assessed under stress and non-stress conditions across 68 environments in seven eastern and southern African countries through the regional on-station trials. Genetic gain was estimated as the slope of the regression of grain yield and other traits against the year of first testing of the hybrid in the regional trial. The results showed highly significant (p< 0.01) annual grain yield gains of 118, 63, 46, and 61 kg ha-1 year-1 under optimum, low N, managed drought, and random stress conditions, respectively. The gains in grain yield realized in this study under both stress and non-stress conditions were associated with improvements in certain agronomic traits and resistance to major maize diseases. The findings of this study clearly demonstrate the significant progress made in developing productive and multiple stress-tolerant maize hybrids together with other desirable agronomic attributes in CIMMYT's hybrid breeding program.

Microbial Interactions in the Management of Groundnut Stem Rot

Groundnut (Arachis hypogaea L.) is an important oil seed crop in the world belonging to the Leguminosae family. It is one of the essential food and cash crops of our country. In India, a large number of diseases attack groundnut [1]. Among soil borne diseases, stem rot or white mold caused by Sclerotium rolfsii Sacc. [2] is an important disease causing significant yield losses in several groundnut growing countries (Mehan et al., 1994). Sclerotium rolfsii Sacc. is a destructive soil borne fungal pathogen of oil seed crop in India. Different practices are recommended for management of groundnut stem rot such as deep summer ploughing, destruction of plant debris, crop rotation with jowar and bajra, seed treatment with carbendazim or captan or mancozeb or tebuconazole, soil drenching with hexaconazole, application of ammonium sulphate or calcium ammonium nitrate instead of urea and application of gypsum at flowering stage. Further, no single treatment is full proof and disease continues to cause losses in farmers’ fields. Biological control offers an interesting alternative to fungicides for sustainable management of soil borne diseases. Biocontrol is a non-chemical measure, could be effective as chemical control by various techniques. Among the techniques, the mixture of antagonists was studied to enchance the control efficacy. In most studies, the involvement of only mechanism of biological control is demonstrated. Involvement of more than one mechanism has been reported in only a few systems. Use of several biocontrol agents with several mechanisms of control fits in well with the concepts of integrated disease management, in which several means of disease suppression are applied concurrently. When single or more means of mechanisms are not effective, the others may compensate for the former absence. The present study, involved three major bacterial antagonists viz., Streptomyces violaceusniger, Streptomyces exfoliatus and Pseudomonas fluorescens to find out the effective dose of mixtures. The different doses from 10-1 to 10-5 were studied, the dose 10-1 of Streptomyces violaceusniger have more efficiency of 86.70, than S. exfoliatus. The efficacy of Streptomyces violaceusniger with combination of other antagonists were tested and found that, the mixture of Streptomyces violaceusniger and P. fluorescens have synergistic activity than any other combinations which have synergistic factor greater than one.

Genetics, genomics, and breeding of black gram [Vigna mungo (L.) Hepper

Black gram [Vigna mungo (L.) Hepper] is a highly nutritious grain legume crop, mainly grown in South and Southeast Asia, with the largest area in India, where the crop is challenged by several biotic and abiotic stresses leading to significant yield losses. Improving genetic gains to increase on-farm yields is the primary goal of black gram breeding programs. This could be achieved by developing varieties resistant to major diseases like mungbean yellow mosaic disease, urdbean leaf crinkle virus, Cercospora leaf spot, anthracnose, powdery mildew, and insect pests such as whitefly, cowpea aphids, thrips, stem flies, and bruchids. Along with increasing on-farm yields, incorporating market-preferred traits ensures the adoption of improved varieties. Black gram breeding programs rely upon a limited number of parental lines, leading to a narrow genetic base of the developed varieties. For accelerating genetic gain, there is an urgent need to include more diverse genetic material for improving traits for better adaptability and stress resistance in breeding populations. The present review summarizes the importance of black gram, the major biotic and abiotic stresses, available genetic and genomic resources, major traits for potential crop improvement, their inheritance, and the breeding approaches being used in black gram for the development of new varieties.

Triplet Excimer Formation in a DNA Duplex with Silver Ion-Mediated Base Pairs.

The dynamics of excited electronic states in self-assembled structures formed between silver(I) ions and cytosine-containing DNA strands or monomeric cytosine derivatives were investigated by time-resolved infrared (TRIR) spectroscopy and quantum mechanical calculations. The steady-state and time-resolved spectra depend sensitively on the underlying structures, which change with pH and the nucleobase and silver ion concentrations. At pH ∼ 4 and low dC20 strand concentration, an intramolecularly folded i-motif is observed, in which protons, and not silver ions, mediate C-C base pairing. However, at the higher strand concentrations used in the TRIR measurements, dC20 strands associate pairwise to yield duplex structures containing C-Ag+-C base pairs with a high degree of propeller twisting. UV excitation of the silver ion-mediated duplex produces a long-lived excited state, which we assign to a triplet excimer state localized on a pair of stacked cytosines. The computational results indicate that the propeller-twisted motifs induced by metal-ion binding are responsible for the enhanced intersystem crossing that populates the triplet state and not a generic heavy atom effect. Although triplet excimer states have been discussed frequently as intermediates in the formation of cyclobutane pyrimidine dimers, we find neither computational nor experimental evidence for cytosine-cytosine photoproduct formation in the systems studied. These findings provide a rare demonstration of a long-lived triplet excited state that is formed in a significant yield in a DNA duplex, demonstrating that supramolecular structural changes induced by metal ion binding profoundly affect DNA photophysics.

Agronomic assessment of rice genotypes (Oryza sativa) under different levels of fertilizer application: A review

The current rice production system, centered around the high-input green revolution methods, tends to favour affluent farmers, leaving lower-income farmers unable to fully embrace modern agricultural techniques due to soaring input prices. In India, shrinking cultivable land and a growing population have led to intensified agronomic practices like heavy chemical fertilizer usage mainly impacting soil health and crops productivity especially rice. This trend has discouraged poorer farmers from rice cultivation due to diminishing factor productivity and profitability amidst rising input expenses, posing significant concerns about sustainability and economic viability. In this context, the review aims to assess how rice (Oryza sativa L.) genotypes perform when exposed to varying levels of fertilizer application, providing valuable insights into their adaptability and potential for increased productivity and soil fertility. It was investigated how different fertilizer levels, specifically nitrogen, phosphorus, and potassium, affects important agronomic practices, yield-related parameters, and grain quality in various rice genotypes. A diverse set of genotypes represent a broad spectrum of genetic background and adaptation strategies, including those known for their efficiency in using nutrients. Highlighting how the robustness of certain genotypes under conditions with limited nutrients maintained satisfactory yields and grain quality. In contrast, some genotypes demonstrated superior performance under higher fertility conditions, resulting in significant yield increases, larger grain sizes, and improved nutritional profiles. These approaches optimize fertilizer application, reduce the environmental impacts associated with excessive nutrient use, and ultimately enhance overall rice production.

Lodging Variability in Sorghum Stalks Is Dependent on the Biomechanical and Chemical Composition of the Stalk Rinds

Stalk lodging contributes to significant crop yield losses. Therefore, understanding the biomechanical strength and structural rigidity of grain stalks can contribute to improving stalk lodging resistance in crops. From the structural constituents of the stalk, the rind provides the principal structure, supporting cells against tension and bending loads. In this work, the biomechanical and viscoelastic behavior of the rind from the internodes of two sweet sorghum varieties (Della and REDforGREEN (RG)), grown in two different growing seasons, were evaluated by three-point micro-bending tests using a dynamic mechanical analyzer (DMA). In addition, the chemical composition of rinds and the microfibril angle (MFA) of the cell wall were determined using XRD. The results revealed that the biomechanical behavior of Della varieties was stiffer and more resistant to loads than that of RG varieties. Two features of the rind biomechanical properties, flexural modulus (FM) and flexural strength (FS), showed a significant reduction for RG. Particularly, a reduction in FS of 16–37% and in FM of 22–41% were detected for RG1. Changes in the stalks’ rind biomechanical properties were attributed to cell wall components. Total lignin and glucan/cellulose contents were positively correlated with the FM and FS of the rind. Subsequently, an increase in the two cell wall components drove an increase in stiffness. Furthermore, the MFA of the rind was also found to influence the rind strength.