Yield Loss Research Articles

Marker assisted selection and genome recovery for heat tolerance in segregants of rice (Oryza sativa L.)

Abstract In the present global warming scenario, it is urgent to impart heat tolerance into the popular high yielding rice (Oryza sativa L.) varieties to reduce yield loss to a great extent. Uma (a prevalent red-grained rice variety in Kerala) was crossed with Nagina 22 (N22), the popular donor for heat tolerance. From the seven promising heat-tolerant F3 plants previously identified through marker assisted selection and field screening, F4 lines (58 nos.) were raised and characterised morphologically. Heat tolerance was scored under natural heat stress during hot summer months in field conditions. Among the evaluated F4 progenies, 26 promising plants registered >75% spikelet fertility. Double panicles were observed in some of the tillers of fourteen F4 plants. During the selection with reported polymorphic markers between parents, all the 26 F4 plants produced the corresponding amplicon for RM5749 (linked marker for heat tolerance in the parental cross Uma x N22) and also for RM9, RM201, RM208, RM225, RM242, RM495, RM3586, RM6100, RM6836, and RM26212, corresponding to the heat tolerant parent N22. Genomic analysis revealed 64% recovery of the Uma genome in seven F4 plants, with maximum genomic regions of Uma on the chromosomes 3 and 5. These promising F4 plants could be forwarded to generate stable and high yielding heat tolerant rice varieties. The identified markers could be used for linkage analysis and QTL mapping in future. Keywords: Heat stress; Rice; spikelet fertility; SSR; QTL

Bacteria as potential biocontrol agents for managing purple witchweed (Striga hermonthica) in grain sorghum

Abstract Purple witchweed [Striga hermonthica (Delile) Benth.], a highly destructive parasitic weed, poses a significant threat to sorghum [Sorghum bicolor (L.) Moench] cultivation. This hemiparasitic plant intrudes its root system into the host plant, leading to substantial yield losses, particularly in susceptible genotypes. In the pursuit of eco-friendly solutions, the biocontrol approach has gained attention as a potential management strategy for Striga. In this study, 13 bacterial strains belonging to the genera Bacillus, Gluconobacter, Pseudomonas, and Streptomyces were investigated in vitro for their efficiency in controlling the early-stage development of Striga. Among the tested strains, Streptomyces morookaensis NRRL B-12429 demonstrated significant inhibition of Striga seed germination and radicle elongation at 54.36% and 61.84%, respectively, when applied to preconditioned seeds with a synthetic germination stimulant. The effect of S. morookaensis on the inhibition of Striga seed germination was more pronounced in the presence of the host plant, sorghum, at 62.35%. However, biopriming of sorghum seeds with S. morookaensis did not enhance the inhibitory effects on Striga seed germination but resulted in a greater reduction in radicle elongation at 74.64% compared with non-primed seeds. Additionally, the biopriming with S. morookaensis promoted the growth of shoots and roots of germinating sorghum, regardless of the presence of Striga seeds. These findings highlight the potential of S. morookaensis strain NRRL B-12429 as a viable candidate for biocontrol agent applications in sorghum cultivation. Further exploration and investigation of its biocontrol capabilities can provide valuable insights for sustainable management practices against Striga infestations.

A Review of the Arrival, Effects, and Management of Bagrada hilaris in South America: The Case of Chile

Biological invasions are partly defined by their ability to spread rapidly within invaded regions, posing threats to biodiversity and local species assemblages. The painted bug, Bagrada hilaris (Hemiptera, Pentatomidae) (Burmeister, 1835), originally described as being from India, is an important pest worldwide, mainly due to the serious economic losses incurred and the large number of zones invaded. Since its initial detection in Chile in 2016, the invasive and destructive paint bug has started its invasion to the east and invaded new areas in South America. Without adequate control methods, the insect may threaten brassica crop production, resulting in yield losses greater than 70% in recently infested areas. The extraordinarily wide range of the B. hilaris invasion has necessitated studies describing its biology and ecology, as well as highlighting the urgent need for effective and long-term management techniques. Hence, thoroughly revising the data on this pest in new areas that have been invaded, as well as in the area of origin, is expected to enable the development of management programs. This review incorporates information on B. hilaris in South America, including the invasion, ecology, and potential management approaches, which may allow for efficient integrated pest management, mainly in Chile. Lastly, researchers are expected to break the bottlenecks of some key issues, offering valuable perspectives for identifying strategies that warrant additional research as potential biological control agents for B. hilaris in South America, utilizing either augmentative or conservation biological control approaches, as well as semiochemicals and cultural practices.

Prevalence of the Potato virus Y strain composition impacting Michigan seed potato production

Potato virus Y (PVY) is a complex of multiple strains that cause a variety of foliar and tuber symptoms. Several current strains have potential to result in variety-dependent yield and quality losses. Understanding the local PVY strain population and variety responses are critical for detection and management. From 2019-2023, PVY strain composition was monitored across seven Michigan seed potato-producing counties growing prevalent chip, russet, and tablestock market classes. Using multiplex reverse-transcriptase polymerase chain reaction methods, PVY strains were identified from potato tuber or leaf samples collected through the certification program (N = 78 positive lots). PVYN-Wi remained most prevalent in Michigan, however, tuber necrotic strains PVYNTN and PVYE also continued to be detected. These, as well as some PVYN-Wi isolates, are known to cause necrotic symptoms in tubers, causing yield and quality reductions for susceptible potato cultivars. As in other U.S. potato-growing regions, PVYN-Wi and PVYNTN were most prevalent in Michigan seed potato lots. Of note, mild to severe tuber necrosis was observed in diagnostic samples positive with local PVYN-Wi strains. Parental strain PVYO appeared to re-emerge in 2023 and should be considered in certification and management. Mild or asymptomatic reactions may still lead to yield or quality losses and may pose a risk to more susceptible cultivars. Due to the diversity of strains and varieties prevalent in the Great Lakes region, continued uniform certification is recommended. Information gathered from this and future survey efforts will be valuable for growers, inspectors, and future breeding and selection efforts.

Evaluating tomato lines resistance to Late Blight and molecular genetic screening with the use of molecular markers

Relevance. Tomato late blight caused by Phytophthora infestans can cause almost 100% yield loss in open ground in cool and humid conditions. At the same time, the genetic characteristics of P. infestans allow it to overcome the genetic resistance of host plants over time, which requires breeders to look for new genes for resistance to late blight and to obtain new varieties that have several resistance genes at once.Material and methods. 12 tomato lines, or a total of 335 plants, were obtained from the N.N. Timofeev breeding station collection and planted in an artificially infected background. For molecular genetic screening, 12 plants from the Kr6 line were used. The markers linked to the late blight resistance genes Ph-3, R1, and R3a were utilized.Results. On an artificial infectious background, phenotypic evaluation of tomato resistance to late blight showed 1 line of plants free of pathogen damage, 5 lines of plants fully afflicted by late blight, and 6 lines with only partial plant damage. According to molecular genetic investigation the resistant plants were heterozygotes for the Ph-3 gene. Furthermore, the R1 gene was present in most of the plants under study; but, without the Ph-3 gene, this gene did not provide plant resistance against late blight.Conclusions. The results of this research led to the selection of tomato plants for further breeding that were resistant to late blight. It was shown that markers linked to the Ph-3 and R1 genes might be used for marker-mediated selection. Furthermore, it has been established that tomato plants are more effectively protected against P. infestans when several resistance genes are present.

Breeding for water-logging tolerance in pigeonpea: current status and future prospects

AbstractPigeonpea is grown in semi-arid tropics where the annual precipitation ranges from 200 to 800 mm and soil orders comprising of Inceptisols, Entisols, Alfisols, Vertisols, Mixed soils, and Aridisols. During monsoons, the semi-arid tropics also receive up to 140–180 mm/day rainfall for a span of 5–10 days, highlighting the chances of waterlogging in an early vegetative stage of pigeonpea, causing 25–30% yield loss in the Indian subcontinent. Waterlogging is a state where soil reaches saturation at submergence, creating an anaerobic condition in the root zone of the plants. As a result, plant withering, leaf chlorosis, stunted growth, lowered photosynthetic rate and plant mortality is evidenced widely. In response to waterlogging, the formation of aerenchyma cells, lenticels and adventitious roots were noticed as morphological adaptations. Whereas, the production of proline, peroxidase, superoxide dismutase, ethylene and alcohol dehydrogenase (ADH) as biochemical modifications. The minimal breeding efforts for waterlogging tolerance in pigeonpea may be the reason for the susceptibility of current varieties to waterlogging stress. This review emphasized the importance of breeding for waterlogging tolerance in pigeonpea. It focused on the morphological, physiological and biochemical adaptations of a plant when subjected to waterlogging stress. It accentuated the need for a standard screening protocol for waterlogging tolerance. Breeding strategies inclusive of novel single pod descent method, marker-assisted selection and rapid generation advancement techniques are discussed in detail.

Clinical Findings, Laboratory Results, Electrocardiography and Echocardiography Findings in Dairy Buffaloes with Theileriosis.

Tropical theileriosis is a tick-borne haemoprotozoan disease, and cardiac function assessment in buffaloes with theileriosis was poorly documented. The Present study was carried out from April 2022 to December 2022. Theileriosis was confirmed by microscopic examination of stained blood smears and lymphnode smearsfurther confirmed by PCR assay. Electrocardiography was performed byusing the base apex lead system, and echocardiography was performed byusing the right parasternal view. The incidence of theileriosis was 16.25% by examination of stained blood smears, and 30.42% by PCR examination in 240 buffaloes. Repeatedly noted clinical signs were the absence of rumination, anorexia, loss of milk yield, depressed demeanour, emaciation, hyperthermia, lymphadenopathy, tick infestation, tachycardia, cardiac arrhythmia, and increased intensity of heartbeat. Haematological findings disclosed decreased haemoglobin, packed cell volume, total erythrocyte count, and neutrophils; increased eosinophils and monocytes. Serum biochemical findings revealed decreased albumin, albumin/globulin ratio, glucose, calcium, phosphorous, sodium, potassium, and chloride; increased globulin, aspartate aminotransferase, bilirubin, blood urea nitrogen, creatinine, cholesterol, lactate dehydrogenase, gamma-glutamyl transferase, and creatine kinase myocardial band isoenzymes. Electrocardiography explorations were sinus tachycardia, broad T wave, and sinus arrhythmia. Echocardiography examination showed ventricular wall thickening, cardiac chamber dilatation, valvular defects/valvular regurgitation, and pericarditis/cardiac tamponade. The present research proposes the changes in the electrocardiography and echocardiography findings in buffaloes with theileriosis, which are essential in clinics to identify the secondary complications during theileriosis and formulate therapeutics.

Economic Assessment of Tuta Absoluta Effect on Tomato Production in East Nawalparasi

Tuta absoluta is an invasive and highly destructive pest of tomato plants, originated in South America, specifically Peru. It has the capability to infest and cause extensive damage to large areas of cultivated tomato fields, as well as other plants in the solanaceous family. This study aims to assess the economic analysis of effect of Tuta absoluta on tomato production. The study was carried out in Kawasoti municipality, Madhyabindu municipality, and Hupsekot rural municipality of East Nawalparasi district of Nepal. They were selected purposively as research sites as the problem of Tuta was more prominent in these localities. Ninety households that were involved in tomato cultivation were selected through the simple random sampling method for the survey. The primary data were collected through individual respondents through pre-tested questionnaires, face-to-face questionnaire surveys, key informant interviews, and focus group discussions. Descriptive statistics, scaling & indexing were used to analyze the data. Most of the farmers cultivated tomatoes in open fields (68.8%) only whereas 26.6% of farmers cultivated in plastic tunnels. The insect pest problem was ranked as the first major problem of farmers. The study revealed that all of the farmers had problems with Tuta in their tomato fields. The minimum yield loss due to Tuta absoluta was 10% and the maximum loss was 80%. The total variable cost (T.V.C) for tomato production in one kathha is NRs. 11210. Average production of tomato per kathha was 550 kg. Gross return and gross margin from tomato cultivation in 1 kathhaare NRs. 16500 with Benefit Cost Ratio (BCR) of 1.64. The average loss of tomatoes per kathha was 72 kg. Only 20 % of the farmers had knowledge regarding the life cycle Tuta absoluta. The most affected stage by Tuta was the flowering stage. This study suggests that effective management of Tuta absoluta can substantially improve tomato production.

Mechanical Leaf Removal for Improved Botrytis Bunch Rot Control in Vitis vinifera 'Pinot gris' and 'Pinot noir' Grapevines in the Northeastern United States.

Late-season bunch rot can cause substantial yield loss in grapevines grown in humid regions. Fruit-zone leaf removal has been widely used to reduce bunch rot and pesticide applications through improvements in canopy microclimate and grape cluster morphology. In this study, we evaluated whether mechanical leaf removal can be a valid alternative to a labor-intensive manual application by comparing prebloom manual (PB-MA) and mechanical (PB-ME) leaf removal. We also evaluated the effects of the timing of mechanical application, prebloom (PB-ME) versus fruit set (FS-ME), on fruit traits and bunch rot, caused by Botrytis cinerea. Our trials were conducted on two Vitis vinifera 'Pinot noir' and 'Pinot gris' vineyards in the Northeastern United States over two seasons (2017 to 2018). Major findings were overall consistent between cultivars and years. Leaf removal provided reductions in fruit-zone canopy density regardless of method or timing. In general, PB-ME provided similar shifts in cluster morphological traits to PB-MA, including lower number of berries per cluster, cluster compactness, and cluster weight compared with control (no leaf removal) vines. At harvest, both prebloom leaf removal methods equally reduced Botrytis bunch rot severity, whereas Botrytis bunch rot incidence in Pinot noir was lowest for PB-ME in 1 year and PB-MA in the next year. When comparing timing of mechanical leaf removal, FS-ME provided Botrytis bunch rot reductions similar to PB-ME, without effects on cluster weight. Thus, under our growing conditions, FS-ME was considered the best mechanical leaf removal option to help manage Botrytis bunch rot without causing undesirable yield reductions.

T2T genomes of carrot and Alternaria dauci and their utility for understanding host-pathogen interactions during carrot leaf blight disease.

Carrot (Daucus carota) is one of the most popular and nutritious vegetable crops worldwide. However, significant yield losses occur every year due to leaf blight, a disease caused by a fungal pathogen (Alternaria dauci). Past research on resistance to leaf blight disease in carrots has been slow because of the low-quality genome assemblies of both carrot and the pathogen. Here, we report the greatly improved assemblies and annotations of telomere-to-telomere (T2T) reference genomes of carrot DH13M14 (451.04 Mb) and A. dauci A2016 (34.91 Mb). Compared with the previous carrot genome versions, our assembly featured notable improvements in genome size, continuity, and completeness of centromeres and telomeres. In addition, we generated a time course transcriptomic atlas during the infection of carrots by A. dauci and captured their dynamic gene expression reprogramming during the interaction process. During infection, A. dauci genes encoding effectors and enzymes responsible for the degradation of plant cell wall components, e.g., cellulose and pectin, were identified, which appeared to increase pathogenic ability through upregulation. In carrot, the coordinated gene expression of components of pattern- and effector-triggered immunity (PTI and ETI) in response to A. dauci attack was characterized. The biosynthesis or signal transduction of plant hormones, including JA, SA, and ethylene, was also involved in the carrot response to A. dauci. This work provides a foundation for understanding A. dauci pathogenic progression and carrot defense mechanisms to improve carrot resistance to leaf blight disease. The Carrot Database (CDB) developed also provides a useful resource for the carrot community.

Palladium-Functionalized Polysiloxane Drop-Casted on Carbon Paper as a Heterogeneous Catalyst for the Suzuki-Miyaura Reaction.

In this work, a Pd(II)-C,N-cyclometalated complex was grafted to polysiloxanes via azide-alkyne cycloaddition. The obtained polymer-metal complex (Pd-PDMS) acts as a catalyst in the Suzuki-Miyaura reaction. Pd-PDMS was drop-casted onto a carbon fiber support, and the resulting membrane demonstrated catalytic activity in the cross-coupling reaction without yield loss after several catalytic cycles. The catalytic membrane allows for easy catalyst recycling and provides ultra-low palladium levels in Suzuki-Miyaura reaction products.

Development and assessment of Nirgundi-Chakramardha biopesticide against Diamondback Moth on Cabbage

Introduction: The global population is rapidly approaching 9.7 billion by 2050, with Africa and Asia playing significant roles in this growth. This surge necessitates increased crop production, highlighting the importance of effective pest control to ensure food security. India, facing an annual crop loss of about 30% due to pests and diseases, emphasizes the urgency of maintaining ecological balance in natural ecosystems. The diamond back moth (Plutella xylostella L.) poses a substantial threat to cruciferous plants globally, causing severe yield losses of 50–80% in infested cabbage. Addressing this challenge is crucial for minimizing crop losses and securing successful harvests. Our study aimed to analyze the emergence and abundance of small, medium, and large-sized larvae before and after applying treatments. Materials and Methods: A study with five treatments, including Nirgundi-chakramardha biopesticide and a control (Cypermethrin), was conducted. Each treatment was replicated four times, and the entire experiment was set up using a randomized block design. Results: After chemical application, all treatments displayed significant differences. The biopesticide in our study produced notable results within trial groups. Notably, the control group exhibited excellent results compared to the other treatments. Conclusion: The Nirgundi-chakramardha Biopesticide exhibited insecticidal activity against Diamondback moth pests, specifically targeting medium-sized larvae. Although not statistically significant compared to the control group, its efficacy in pest control, especially during the larval stage, indicates its potential as a viable pest management option. Further research and optimization could improve its effectiveness in combating Diamondback moth infestations.

Interactive effects of nitrogen and genotype on maize rough dwarf disease

AbstractNitrogen and genotype play vital roles in modulating plant disease resistance. Maize (Zea mays L.) rough dwarf disease (MRDD) is a global viral disease that has caused serious yield losses. However, it is not clear how nitrogen and genotype interact to affect MRDD. We conducted field experiments in 2011 and 2013 to investigate the MRDD incidence, yield, and yield loss rate of 59 maize hybrids under high nitrogen (HN) and low nitrogen (LN). Compared with HN, the MRDD incidence and yield loss rate of S‐sensitive hybrids (nitrogen significantly influenced MRDD incidence in susceptible genotypes) could be significantly reduced by 50.6% and 35.5%, respectively, in LN without compromising maize yield. In contrast, R‐insensitive types (resistant hybrids in which MRDD incidence was unresponsive to nitrogen treatment) could maintain high MRDD resistance and yield at HN. US hybrid 78599 and inbred line Dan340 were the main parental resources of the resistant genotypes, and inbred lines Huangzao4 and Ye478 were the main parental resources of the susceptible genotypes. The physiological mechanism leading to increased MRDD incidence was thought to be higher nitrogen concentrations in the stalks. This study provided theoretical support for using reasonable nitrogen management to control MRDD and breeding MRDD‐resistant maize hybrids.

Artificial Neural Network Model for Predicting Carrot Root Yield Loss in Relation to Mechanical Heading

Modelling and predicting agricultural production processes have high cognitive and practical values. Plant growth, the threat of pathogens and pests, and the structure of agricultural machinery treatments are mostly non-linear, measurable processes that can be described mathematically. In this paper, a multiple regression analysis was carried out in the first step to check the non-linearity of the data and yielded a coefficient of determination of R2 = 0.9741 and the coefficient of determination corrected for degrees of freedom was R2adj = 0.9739. An artificial neural network model, called CH-NET, is then presented to predict the yield loss of carrot roots by leaving root mass in the field during harvest at the mechanical heading stage. The proposed network model has an architecture consisting of an input layer, three hidden layers with 12 neurons each, and an output layer with one neuron. Twelve input criteria were defined for the analysis and testing of the network, eight of which related to carrot root parameters and four to the heading machine. The training, testing, and validation database of the CH-NET network consisted of the results of field trials and tests of the operation of the patented (P.242097) root heading machine. The proposed CH-NET neural network model achieved global error (GE) values of 0.0931 t·ha−1 for predicting carrot root yield losses for all twelve criteria adopted. However, when the number of criteria is reduced to eight, the error increased to 0.0991 t·ha−1. That is, the prediction was realised with an accuracy of 90.69%. The developed CH-NET model allows the prediction of economic losses associated with root mass left in the field or contamination of the raw material with undercut leaves. The simulations carried out showed that minimum root losses (0.263 t·ha−1) occur at an average root head projection height of 38 mm and a heading height of 20 mm from the ridge surface.

Development of ExG, ExR, ExGR, HSV, CIELAB Images from RGB Images Using Image Segmentation Algorithm in Computer Vision Based Herbicide Spraying Applications

Weed management in agriculture is critical for preventing crop yield losses, with traditional methods often leading to environmental harm and increased production costs. This study explores the development of color indices and models for weed detection in computer vision-based herbicide spraying applications. Among the all sensors, RGB colour cameras offer several advantages, including low cost and wide availability of image processing libraries tailored for RGB image analysis. In present study a Logitech C270 webcam was used for acquiring the RGB images and a specially python algorithm was developed for image segmentation based on color. Excess Green (ExG), Excess Red (ExR), Excess Green minus Red (ExGR), HSV, and CIELAB color model images are developed by using algorithm. The research demonstrates that while ExG and ExGR indices are effective under specific conditions, the CIELAB model offers superior segmentation results across varying lighting environments. Among all these color indices and models, particularly CIELAB, can enhance the precision of weed detection in automated herbicide applications, thereby reducing environmental impact and improving agricultural efficiency.

Trade can buffer climate-induced risks and volatilities in crop supply

Abstract Climate change is intensifying the frequency and severity of extreme events, posing challenges to food security. Corn, a staple crop for billions, is particularly vulnerable to heat stress, a primary driver of yield variability. While many studies have examined climate impact on average corn yields, little attention has been given to the climate impact on production volatility. This study investigates the future volatility and risks associated with global corn supply under climate change, evaluating the potential benefits of two key adaptation strategies: irrigation and market integration. A statistical model is employed to estimate corn yield response to heat stress and utilize NEX-GDDP-CMIP6 climate data to project future production volatility and risks of substantial yield losses. Three metrics are introduced to quantify these risks: Sigma (σ), the standard deviation of year-on-year yield change, which reflects overall yield volatility; Rho (ρ), the risk of substantial loss, defined as the probability of yield falling below a critical threshold; and Beta (β), a relative risk coefficient that captures the volatility of a region's corn production compared to the globally integrated market. The analysis reveals a concerning trend of increasing year-on-year yield volatility (σ) across most regions and climate models. This volatility increase is significant for key corn-producing regions like Brazil and the United States. While irrigated corn production exhibits a smaller rise in volatility, suggesting irrigation as a potential buffer against climate change impacts, it is not a sustainable option as it can cause groundwater depletion. On the other hand, global market integration reduces overall volatility and market risks significantly with less sustainability concerns. These findings highlight the importance of a multidimensional approach to adaptation in the food sector. While irrigation can benefit individual farmers, promoting global market integration offers a broader solution for fostering resilience and sustainability across the entire food system.

A Nanopore-sequenced high-quality genome of the Bipolaris oryzae strain Bo-1.

Brown spot disease of rice caused by Bipolaris oryzae results in severe yield losses. A high-quality genome was assembled using Nanopore sequencing data, resulting in a 36-Mb nuclear genome with 19 contigs and a mitogenome. This assembly provides valuable genetic resources for investigations of rice-B. oryzae interactions.

Foliar blight, leaf spot, and stem blackening diseases caused by Stemphylium beticola, Alternaria alternata, and Alternaria atra on dragon's head (Lallemantia iberica) in Iran

Dragon's head, Lallemantia iberica, is an oilseed crop adapted to be grown in cold-dry areas. In the growing season of 2022–23 a severe foliar blight, leaf spot, and stem blacking symptoms were observed in commercial fields in northern and northwestern Iran, leading to more than 50 % yield loss. Infected samples were collected and transferred to the laboratory. Following the isolation of fungal agents, five representative isolates were selected for further studies. Morphological studies, based on conidial shape, conidiation, and other mycological characteristics, were carried out on a pure culture established from a single spore. Furthermore, multigene phylogenetic analyses were performed using sequences of translation elongation factor 1-α (TEF1), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), RNA polymerase II second largest subunit (RPB2), and Internal Transcribed Spacer (ITS) rDNA genes for Alternaria isolates, along with calmodulin (cmdA) for the Stemphylium isolate. The morphological and molecular studies identified the fungal isolates as Alternaria atra, Alternaria alternata, and Stemphyliium beticola. Pathogenicity tests on the commercial cultivar ‘Sara’ indicated that all isolates were pathogenic to dragon's head, but they differed significantly in aggressiveness. To the best of our knowledge, this is the first report of the association of these fungal species with an important foliar disease on this crop in Iran and worldwide.

Evaluation of Early Maturing Soya Bean (Glycine max.) Genotypes for Pod Shattering Resistance and High Yielder at Western Tigray, Ethiopia

Pod shattering is occurring after the pods reached maturity which can cause considerable yield loss in soya bean crop. The aims of this study were to evaluate the pod shattering resistance and the performance of the agronomic traits of several soybean genotypes. Field experiment was conducted at Humera district during 2018 cropping season using sixteen soya bean genotypes. Treatments were evaluated with RCBD and replicated three times. Pod shattering, number of branches, seed per pod, pod per plant, hundred seed weight and seed yield was shows a significant (P<0.01) variation among genotypes. While; there was not a significant variation among genotypes in terms of the number of days from planting to flowering and maturity. The mean pod shattering was ranged from scale1.25 to 4. Maximum amount of pod shattering was measured in the genotypes PI423959 (4), PI506764 (3.75) and PI417085 (3.25). However, minimum amount of pod shattering was measured in the genotypes of PI417116 (1.25), Desha (1.75) and PI417132 (2). Highest yield was obtained from the genotypes PI714116 (19.29kg/ha) and PI417132 (16.54kg/ha). However, lowest yield was obtained from the genotypes Williams (check) (6.7kg/ha) followed by PI223963 (8.53 kg/ha) and Nova (check) (9.86 kg/ha).

Compound extreme climate events intensify yield anomalies of winter wheat in France

Abstract Compound extreme climate events (ECEs) are increasingly recognized for their potential to exacerbate food insecurity risks beyond those posed by isolated events. The notion of ‘compound event’ encompasses not only co-occurring ECEs but also multiple ECEs across (different) growth stages (mECEs). The additional effects of these mECEs on crop yield, particularly considering various types of ECEs and regional scales, remain poorly understood. To close this knowledge gap, we consider droughts, pluvials, heatwaves, and coldwaves, and further identify which types of compound events have additional effects on winter wheat yield in France, using statistical methods and datasets encompassing 94 counties over a 68-year period. Our results indicate co-occurring drought heatwaves in summer and spring, along with co-occurring pluvial heatwaves and pluvial coldwaves in winter, have negative additional effects on yield compared with single ECEs. We further identify the types of mECEs that have intensified effects, with the majority showing negative effects on yield. Key interactions leading to intensified yield loss include droughts in winter or spring combined with summer co-occurring drought heatwaves, pluvials across multiple growth stages, pluvials combined with coldwaves, and the transition between droughts and pluvials, with the most severe anomaly attaining −17.2%. Coldwaves are the main ECE related to intensified yield increases, while their frequency is decreasing. Overall, this study stresses the interactions among ECEs on crop yield, and the identified types of mECEs could serve as foundational information for designing control experiments and improving process-based crop models.