High Yield Potential Research Articles

Assessment of Terminal Heat Stress Tolerance in Doubled Haploids Derived from Synthetic Hexaploid Wheat (Triticum aestivum L.) Using Genetic Variability and PCA-based Cluster Analyses

A comprehensive study was conducted on germplasm derived from two synthetic wheats and two hexaploid wheats i.e., SHW14102 x BWL4444, SHW14102 x BWL3531, and SHW3761 x BWL4444 to identify the potential doubled haploids that can withstand high temperatures, particularly at the reproductive stage during crop seasons viz., 2020–2021 and 2021–2022. The doubled haploid lines were selected based on phenotypic characteristics using genetic variability analysis. In the preliminary field trial evaluation, 100 lines were selected based on high phenotypic uniformity for further testing against terminal heat stress conditions and high yield potential. Among these, 17 lines had relatively higher values for days to biomass yield, grain yield, thousand-grain weight, and harvest index and relatively lower values for maturity, and grain filling duration based on principal component and cluster analyses. Principal component analysis (PCA) based cluster analysis exhibited that, clusters II and III had clear separation compared to cluster I. All three clusters were analyzed according to their means and standard deviations. The mean values for GYP (385.07), BMYP (1162.37), and TGW (38.13) were relatively higher in cluster 1 than in other clusters. Cluster 2 exhibited a higher value for DH (89.14), SL with awns (18.21), and GFD (18.19) while cluster 3 showed a higher value for HI (41.02). Thus, it was concluded that cluster I demonstrated superior performance in grain yield per plant, biomass yield per plant, and thousand-grain weight, indicating its overall higher productivity compared to the other clusters under terminal heat stress conditions and suggesting them as potential germplasm for future breeding programs.

Potential, economic and ecological benefits of sweet sorghum bio-industry in China

BackgroundSweet sorghum (Sorghum bicolor) displays an excellent potential to serve as a non-food bioenergy feedstock for bioethanol production in China due to its high potential yield on marginal lands. However, few studies have been conducted on the potential of sweet sorghum yield and appropriate industrial models in different marginal regions in China. This study explored the spatial distribution of potential sweet sorghum production using the Decision Support System for Agrotechnology Transfer (DSSAT) model and proposed three typical industrial models of sweet sorghum industry to calculate their economic and ecological benefits.ResultsThe results indicate that considering the factors of land use, annual precipitation, soil salinity, soil pH, and accumulated temperature, approximately 32.23 million ha of marginal land are suitable for sweet sorghum cultivation in China, and 130 million tonnes (t) of ethanol can be produced. Further, the development of the sweet sorghum industry under the three models can generate 1425.49 billion CNY potential, approximately accounting for 3.57% of industrial added value in China if measured against 2023 levels, and reduce CO2 emissions by 4.68 million t.ConclusionsThis study provides an innovative perspective for the multi-industry large-scale promotion of sweet sorghum in different marginal lands based on the high spatial resolution Geographic Information System (GIS) data by the DSSAT model with a Life Cycle Assessment (LCA) method, and this applies not only to China but also to the worldwide and other types of energy plants.

Catiknifap, new native variety of Xcat ik pepper (Capsicum annuum L.)

O Objective: To describe the morphological and agronomic characteristics of Catiknifap, a native variety of the Xcat ik pepper. Design/Methodology/Approach: Catiknifap was formed by mass selection method from a P108 accession collected in 2013 in Muna, Yucatan. Characterization and yield trails were carried out in greenhouse during three cycles from 2021 to 2022. Forty-five characteristics were evaluated based on UPOV guidelines. Results: Catiknifap is an early-ripening variety. Its fruits ripen between 77 and 81 days after transplanting. Its main morphological characteristic is the rounded shape at the junction with the peduncle. The yield depends on the growing season and ranges from 32.3 to 42.3 t ha-1. Study Limitations/Implications: Assays were carried out in greenhouses. Pests and diseases may cause differences in open field yield. Findings/Conclusions: Catiknifap is the first morphologically characterized variety of Xcat ik pepper. The fruits of this homogenous and stable variety have a high yield potential in Yucatan.

Yield of winter soft wheat varieties of different ecological and geographical origin and their adaptability in the conditions of the Central Nonblack Earth Region

When creating new varieties, it is necessary to pay attention not only to high yields and the quality of the original parent forms, but also to be guided by knowledge about their reaction to changing growing environment conditions. The article presents the results of a comprehensive assessment of 15 varieties of different ecological and geographical origin. The methods of S.A. Eberhart and W.A. Russell, A.A. Rossielle and J. Hamblin, L.A. Zhivotkov, E.D. Nettevich were used in the analysis of adaptability indicators. The research was carried out in the northwestern part of the Ryazan region in the fields of ISA – a branch of the Federal State Budgetary Educational Institution FNAC VIM in 2019–2023, of which two years were unfavorable – the index of environmental conditions (Ij) –2,54 – –1,87, three years favorable Ij was 0,84–2,24. It was found that, on average, over 5 years of research, the highest yield potential was possessed by the varieties of winter wheat Danaya – 5,79 t/ha, Isktar – 6,36 t/ha, Nebokrat and Slavna – 5,81 t/ha and 6,09 t/ha, which is higher than the average annual indicator by experience by 11,1%, 22,1%, 11,5% and 16,9%, respectively. The group of the most plastic varieties includes: Danaya and Lavina (Russia), Nebokrat and Slavna (Ukraine), Isztar (Germany). High responsiveness to improving environmental conditions was noted in winter wheat varieties Moskovskaya 39 (Russia) – 1,22, Fantasia (Belarus) – 1,23, Saturnus and Tambor (Germany) – 1,17 and 1,41, respectively. According to the complex of adaptive properties, the Isztar (Germany) and Nebokrat (Ukraine) varieties were distinguished as genetically flexible ((Ymin + Ymax)/2 from 5,56 to 6,26), with a high level of stability (PUSS from 103,28% to 113,12%), good adaptability to environmental conditions (KA – 1,15% and 1,26%, respectively) and resistance to stress ((Ymin – Ymax) from –4,23 to –4,68). The research results can be used in practical breeding.

Assessing population structure and morpho-molecular characterization of sunflower (Helianthus annuus L.) for elite germplasm identification.

Sunflower (Helianthus annuus L.), known for its adaptability and high yield potential, is vital in global edible oil production. Estimating genetic diversity is a key pre-breeding activity in crop breeding. The current study comprised of 48 genotypes which were assessed for their biometrical traits at department of Oilseeds, Tamil Nadu Agricultural University, during the rainy season of 2022. The lines were subsequently characterised using 103 simple sequence repeat (SSR) markers for molecular diversity analysis. The results indicated that the net nucleotide distances indicated varying genetic divergence, with subpopulations II and V showing the highest (0.056) and I and IV the lowest (0.014). Subpopulation IV exhibited the highest heterozygosity (0.352), while subpopulation III had the lowest heterozygosity and a low Fst (0.173). Principal components analysis (PCA) and hierarchical cluster analysis were employed for assessing the morphological diversity, facilitating genotype grouping and parent selection for breeding programs. The first four components cumulatively accounted for 86.72% of the total variation. Cluster Analysis grouped 48 sunflower genotypes into three clusters based on genetic diversity. COSF 13B stands out for its high head diameter, oil content, seed yield, and oil yield based on mean performance of morphological data. Principal coordinate analysis (PCoA) mirrored the groupings from the Neighbor Joining method, with the first three components explaining 27.24% of the total variation. Molecular data analysis identified five distinct clusters among the germplasm. By integrating morphological and molecular marker data with genetic distance analysis, substantial diversity was revealed with the genotypes RHA 273 and GMU 325 consistently demonstrated high oil yield per plant. The genotypes GMU 477, GMU 450, COSF 13B, RHA 102, CMS 1103B, and RHA GPR 58 have been identified as suitable parents for enhancing oil content in sunflower breeding programs. These findings also aid in selecting SSR markers for genotype characterization and in choosing diverse parents for breeding programs.

Multimodal Deep Learning Integration of Image, Weather, and Phenotypic Data Under Temporal Effects for Early Prediction of Maize Yield

Maize (Zea mays L.) has been shown to be sensitive to temperature deviations, influencing its yield potential. The development of new maize hybrids resilient to unfavourable weather is a desirable aim for crop breeders. In this paper, we showcase the development of a multimodal deep learning model using RGB images, phenotypic, and weather data under temporal effects to predict the yield potential of maize before or during anthesis and silking stages. The main objective of this study was to assess if the inclusion of historical weather data, maize growth captured through imagery, and important phenotypic traits would improve the predictive power of an established multimodal deep learning model. Evaluation of the model performance when training from scratch showed its ability to accurately predict ~89% of hybrids with high-yield potential and demonstrated enhanced explanatory power compared with previously published models. Shapley Additive explanations (SHAP) analysis indicated the top influential features include plant density, hybrid placement in the field, date to anthesis, parental line, temperature, humidity, and solar radiation. Including weather historical data was important for model performance, significantly enhancing the predictive and explanatory power of the model. For future research, the use of the model can move beyond maize yield prediction by fine-tuning the model on other crop data, serving as a potential decision-making tool for crop breeders to determine high-performing individuals from diverse crop types.

Punjab Tar-1: A New Short Duration, High Yielding and Disease Resistance Long Melon Variety (Cucumis melo) Released in Pakistan.

The development of new crop varieties with favorable features is a continuing effort. With the passage of time, a cultivated variety becomes subjected to various biotic and abiotic plant stresses. This article describes development of an innovative and imaginative long melon cultivar called "Punjab Tar-1."This article discusses creation of a novel and inventive long melon variety known as "Punjab Tar-1." Current long melon varieties in Pakistan are sensitive to climatic conditions and susceptible to pest and disease attack. A New Short Duration, High Yielding and Disease Resistance Long Melon Variety (Cucumis melo) is released in Pakistan to address these current issues of long melon varieties A high yielding and early maturing variety of long melon “Punjab Tar-1” has been developed by Vegetable Research Institute, Faisalabad, Pakistan through mass selection. Plants were selected from an open pollinated indigenous source population with main emphasis on earliness, fruit shape, color and taste and yield. Selection intensity was 15% in 1st three selection cycles and 30% in subsequent four selection cycles whereas yield trials were started from 8th selection cycle. The fruit of this variety has a strong longitudinal rib that makes it difficult for eating by caterpillars. This variety has wide adaptability and exhibits stable yield across multiple environments. Notably, "Punjab Tar-1" contains 10.59 % crude protein and 1.08% crude fat content. Genetic uniformity and distinctiveness of this variety was confirmed through SSR polymorphism. Punjab Tar-1 variety has been approved by Punjab Seed Council in its meeting held on 2021 and was recommended for general cultivation in Punjab, Pakistan. Its certified seed is available for farmers at Vegetable Research Institute, Faisalabad. This newly approved variety will aid to save the precious foreign reserves by reducing vegetable seed import bill. In Pakistan, seed market of long melon is occupied by improved varieties. In multi-location evaluation, one said variety has exhibited high yield and stability than exotic germplasm. This is the first variety developed in Pakistan having good taste, early maturity, long shape, and high yield potential. DNA fingerprinting has further confirmed that it is distinct from local material, having novelty and diversity.

Effect of Various Nitrogen Doses and Plant Growth Regulators on Nutrient Uptake and Productivity of Wheat (Triticum aestivum L)

A field experiment was conducted at Research Farm of Bihar Agricultural University, Sabour, Bhagalpur, Bihar, during season of 2019-20, to find out the effect of optimization of nitrogen doses for high yield potential of wheat with plant growth regulators. The experiment was laid out in randomized block and replicated thrice. The experiment ten treatment of different doses of fertilizer with plant growth regulators chlormequat chloride and tebuconazole applied at 0.2% and 0.1% respectively. Experimental revealed that application of 150% recommended doses of NPK resulted significantly higher available nitrogen (171.82 kg ha-1), available phosphorus (27.01 kg ha-1) and available potassium (192.27 kg ha-1) in soil after the harvest of wheat significantly highest nitrogen, phosphorus and potassium uptake by wheat recorded with 150% RDF of NPK with chlormequat chloride (0.2%) and tebuconazole (0.1%). Significantly highest grain and straw yield recorded with 150% NPK + chlormequat chloride (0.2%) and tebuconazole (0.1%) at par with 100% RDF as compare to other treatments harvest index was recorded 125% RDF of N and chlormequat chloride (0.2%) and tebuconazole (0.1%) and 150% RDF of N and chlormequat chloride (0.2%) and tebuconazole (0.1%). The uptake of key nutrients, nitrogen, phosphorus and potassium followed a similar pattern, with 150% recommended doses of NPK along chlormequat chloride (0.2%) and tebuconazole (0.1%). optimal NPK application resulted in positive nutrient balance in the soil. This investigation that managing nutrient with growth regulator in wheat is an economically viable and ecologically sound approach to improve both crop production and soil health through balanced nutrition.

Quality indicators of new sunflower (Helianthus annuus L.) varieties for high oleic and oilseed use under different growing conditions

Purpose. To study the influence of steppe and forest-steppe climatic conditions on the yield, oil content in seeds and fatty acid composition of oil in new sunflower varieties of high oleic and oilseed use. Methods. The research was conducted in accordance with “Methods of qualification examination of plant varieties for their suitability for distribution in Ukraine (general part)” and “Methods of qualification examination of plant varieties for their suitability for distribution. Methods of determining quality indicators of plant production”. The following methods were used in the research: laboratory, comparison, generalisation, mathematical statistics, analysis and synthesis to draw conclusions. Results. The fatty acid composition of the seeds of new varieties of sunflower (Helianthus annuus L.) of high oleic and oilseed use, grown in different soil and climatic conditions, was studied. According to the results of the analysis in the steppe zone, the variety ‘LG50648’ has the highest economic and value characteristics: oil content (51,0%), oleic acid (85.1%), yield (3.11 t/ha); varieties ‘SULIANO’ and ‘MAS 908HOCP’ – yield (3.40 and 3.91 t/ha) and oleic acid content (85.8 and 86.1%) regardless of the gro­wing conditions. It was found that high oleic sunflower varieties ‘MAS 908HOCP’, ‘LG50648’, ‘SULIANO’ grown under steppe and forest-steppe conditions yielded higher quality oil. The maximum content of oleic acid in 2022–2023 was characteristic of the seeds of the varieties ‘MAS 908HOCP’ (86.1% in the steppe and 85.8% in the forest steppe) and ‘SULIANO’. The hi­ghest linoleic acid content was obtained in the seeds of the oilseed use varieties ‘STK104’ (62.9% in the steppe and 58.5% in the forest steppe) and ‘STK103’ (61.2% in the forest steppe). Among the high oleic varieties, the best results were obtained with ‘LG50648’ (5.7% in the steppe and 5.9% in the forest steppe). Conclusions. Oil content of sunflower varieties and fatty acid composition are determined by varietal characteristics of sunflower and environmental conditions. Modern sunflower varieties, which are included in the State Register of Plant Varieties of Ukraine, have high yield potential and can provide a large yield of vegetable oil per unit area. Agroclimatic conditions have different effects on the gross seed yield and oil quality in the conditions of the forest steppe and steppe of Ukraine.

Adaptation to reductions in chilling availability using variation in PLANT HOMOLOGOUS TO PARAFIBROMIN in Brassica napus.

Winter annual crops are sown in late summer or autumn and require chilling to promote flowering the following spring. Floral initiation begins in autumn and winter, and in winter oilseed rape (OSR), continued chilling during flower development is necessary for high yield potential. This can be a problem in areas where chilling is not guaranteed, or as a result of changing climates. Here, we used chilling disruption and low chilling to identify loci with the potential to increase chilling efficiency in winter OSR. We report that time to flowering and yield potential under low chill conditions are affected by variation at the PLANT HOMOLOGOUS TO PARAFIBROMIN gene, a component of the plant PAF1c complex. We show that increases in winter chilling given to developing flowers can improve seed yields and that loss of function of BnaPHP.A05 leads to early flowering in B. rapa and B. napus and an increase in seed set where chilling is limited. Because PHP is known to specifically target the FLOWERING LOCUS C (FLC) gene in Arabidopsis, we propose that variation at PHP is useful for breeding modifications to chilling responses in polyploid crops with multiple copies of the FLC gene.

Exogenous Melatonin as Pre- and Postharvest Application on Quality Attributes, Antioxidant Capacity, and Extension of Shelf Life of Papaya

Papaya is widely grown in tropical and subtropical climates due to its high yield potential and high returns. The vital hormone melatonin, regulating various biological processes in plants, is eco-friendly and less harmful to humans than other chemicals. This study aims to enhance the quality and antioxidant enzyme activities and lessen postharvest senescence in papaya cv. CO 8 fruits during both ambient (32 ± 2 °C and 55 ± 5% RH) and cold storage (10 ± 2 °C and 90–95% RH) as exogenous melatonin (EMT) is applied in varying concentrations. An optimum melatonin dose of 1.5 mM was applied as a pre-harvest spray 15 days before harvest and a postharvest dip proved effective in prolonging shelf life (under ambient it prolonged to day 9 and under cold storage up to 28 days) and delaying ripening and softening. Exogenous melatonin application enhanced antioxidant activity, reduced weight loss, maintained firmness, delayed ripening enzymes, and lowered ethylene and CO2 levels. For instance, control fruits had weight losses between 7.42% and 10.09%, while fruits treated with 1.5 mM melatonin showed 5.74% and 9.06% weight loss under ambient and cold storage, respectively. In conclusion, applying EMT (1.5 mM) could be an economically viable and environmentally benign way to lessen senescence after harvest and preserve the qualities of the papaya fruit during ambient and cold storage.

Reconciling plant and microbial ecological strategies to elucidate cover crop effects on soil carbon and nitrogen cycling

Abstract Plant economics, the way plants allocate and utilize resources, affect multiple soil processes through interactions with root and associated microbial communities. However, the interplay between plant economics and microbial ecological strategies remains poorly understood, which is crucial for integrated manipulation of plant‐ and microbe‐mediated functions in mitigating climate change and sustaining soil health. We used a field experiment with 11 cover crop species grown monocultures in the same base soil to test whether microbial ecological strategies are associated with plant economic strategies and if their interactions are linked to soil functions. A principal component analysis (PCA) was performed on root and leaf traits to identify the loadings of cover crop species on the plant trait space. Metagenomic analysis of rhizosphere microbial communities was conducted to infer their ecological strategies based on genetically encoded community‐aggregated traits. We found a synchronous relationship between the conservation gradient of plant economic strategies and the trade‐offs in microbial ecological strategies. Conservative plant strategists, such as Lolium multiflorum, Triticum turgidum and Brassica juncea, fostered microbial communities characterized by high growth yield potentials (Y‐strategies). This included increased microbial carbon fixation pathways, citrate cycle, ribosome and valine, leucine and isoleucine biosynthesis. As a result, microbial metabolic efficiency improved, shown by higher microbial biomass carbon content and a lower metabolic quotient (qCO2), led to enhanced soil organic carbon accumulation. In comparison, acquisitive plants like Astragalus sinicus, Vicia villosa, Trifolium incarnatum and Medicago sativa stimulated microbial resource‐acquisition strategies (A‐strategies). This included enhanced bacterial chemotaxis, secretion systems, biotin metabolism and cell motility pathways, which in turn increased soil exoenzyme activity and accelerated soil nitrogen mineralization. Consequently, these species enhanced soil nitrogen availability and had substantial feedbacks on subsequent main crop productivity. Synthesis. This study demonstrates how plant economic strategies influence the balance between different microbial ecological strategies, specifically the trade‐offs in Y‐ and A‐strategies. These interactions exert control over carbon and nitrogen dynamics in the soil ecosystem. The findings provide insights for implementing nature‐based solutions to improve agroecosystem management practices.

Influence of Storage Conditions on Four Chipping Potato Cultivars Developed in North Dakota

Cold temperature storage (lower than 10 °C) has been used as a management strategy to extend marketability and reduce potato storage losses. However, cold temperatures may result in dark-colored chips through a process known as cold-induced sweetening (CIS). ‘Dakota Crisp’ and ‘Dakota Diamond’ are two North Dakota State University potato breeding program cultivar releases selected for cold-chipping ability with high tuber yield potential. Two-year storage trials were conducted to examine sugar development and tuber processing quality of four cultivars grown at three nitrogen rates under irrigated and non-irrigated field conditions. The two-way interaction between storage period and storage temperature was significant for sucrose content, glucose content, visual chip color, and Agtron values, indicating a difference in sugar development for each storage temperature profile. Among the four cultivars evaluated under both irrigated and non-irrigated production conditions, ‘Dakota Pearl’ accumulated significantly less sucrose and glucose compared to other cultivars under the same storage conditions. ‘Dakota Crisp’ produced acceptable chip color from 8.9 °C after long term storage, while ‘Dakota Diamond’ produced acceptable chip color from 8.9 °C for up to 6 months of storage. These results emphasize the importance of developing cultivar-specific management profiles including storage and the informational need for producers and processors in determining the best practices for individual cultivars.

Exploiting phenotypic heterogeneity to improve production of glutathione by yeast

BackgroundGene expression noise (variation in gene expression among individual cells of a genetically uniform cell population) can result in heterogenous metabolite production by industrial microorganisms, with cultures containing both low- and high-producing cells. The presence of low-producing individuals may be a factor limiting the potential for high yields. This study tested the hypothesis that low-producing variants in yeast cell populations can be continuously counter-selected, to increase net production of glutathione (GSH) as an exemplar product.ResultsA counter-selection system was engineered in Saccharomyces cerevisiae based on the known feedback inhibition of gamma-glutamylcysteine synthetase (GSH1) gene expression, which is rate limiting for GSH synthesis: the GSH1 ORF and the counter-selectable marker GAP1 were expressed under control of the TEF1 and GSH-regulated GSH1 promoters, respectively. An 18% increase in the mean cellular GSH level was achieved in cultures of the engineered strain supplemented with D-histidine to counter-select cells with high GAP1 expression (i.e. low GSH-producing cells). The phenotype was non-heritable and did not arise from a generic response to D-histidine, unlike that with certain other test-constructs prepared with alternative markers.ConclusionsThe results corroborate that the system developed here improves GSH production by targeting low-producing cells. This supports the potential for exploiting end-product/promoter interactions to enrich high-producing cells in phenotypically heterogeneous populations, in order to improve metabolite production by yeast.

Molecular identification and morphological characterisation of multiple fungal pathogens of triticale in Northern Kazakhstan

Background and Aim. Тtriticale is classified as an amphidiploids and is the first grain crop created by humans, possessing high yield potential along with favorable biochemical and technological characteristics. For a long time, it was believed that triticale, during selection, inherited disease resistance from wheat and resistance to abiotic factors from rye. However, in recent years, there have been several reports that triticale is to fungal diseases, which reduces the quality of the harvested crop. The aim of our study is to examine and characterize the fungal pathogens of triticale in Northern Kazakhstan, and conduct molecular-genetic identification of the main fungal pathogens.MaterialsandMethods. The study was conducted of triticale from two varieties, Dauren and Rossika. Primary fungal isolation was carried out on agarized nutrient media, with preliminary identification using microscopy. Molecular genetic analysis was performed to determine the species of fungi. Results. During the study, we isolated five major fungal pathogens from different parts of the plant. Data on the percentage of infection by the main fungal pathogens were provided. Three of them are pathogens of alternariosis – Alternaria alternate (more common in grains 39%, in leaves and scales of seeds 19-21%), fusariosis – Fusarium tricinctum (occurrence: in roots 57%, in grains 17%, in leaves 10%) and helminthosporiosis – Bipolaris sorokiniana (occurrence in roots and leaves 0.83%) of grain crops, which can lead to a decrease and loss of yield due to their production of mycotoxins. A cultural and morphological description of the main fungal pathogens of grain crops was provided. Moleculargenetic identification was carried out using the ribosomal marker ITS (internal transcribed spacer).Conclusion. According to result of our research, we characterized and molecular-genetically identified the most common fungi found on different parts of the triticale plant.

Improvement of Quality and Disease Resistance for a Heavy-Panicle Hybrid Restorer Line, R600, in Rice (Oryza sativa L.) by Gene Pyramiding Breeding.

The utilization of heavy-panicle hybrid rice exemplifies the successful integration of architectural enhancement and heterosis, which has been widely adopted in the southwest rice-producing area of China. Iterative improvement in disease resistance and grain quality of heavy-panicle hybrid rice varieties is crucial to promote their sustainable utilization. Here, we performed a molecular design breeding strategy to introgress beneficial alleles of broad-spectrum disease resistance and grain quality into a heavy-panicle hybrid backbone restorer line Shuhui 600 (R600). We successfully developed introgression lines through marker-assisted selection to pyramid major genes (Wxb + ALKA-GC + Pigm + Xa23) derived from three parents (Huanghuazhan, I135, I488), which significantly enhance grain quality and confer resistance to rice blast and bacterial blight (BB). The improved parental R600 line (iR600) exhibited superior grain quality and elevated disease resistance while maintaining the heavy-panicle architecture and high-yield capacity of R600. Moreover, the iR600 was crossed with male sterility line 608A to obtain a new heavy-panicle hybrid rice variety with excellent eating and cooking quality (ECQ) and high yield potential. This study presents an effective breeding strategy for rice breeders to expedite the improvement of grain quality and disease resistance in heavy-panicle hybrid rice.

Advancements in breeding for high oil content in maize (Zea mays. L)

Maize is one of the world’s most important food crops, supplying>5% deity energy. Due to its wider adaptability, high yield potential, maize is widely utilized as food and animals world worldwide. It enriched with caloric starch and the high energy in its oil. The kernel oil content in commercial high-oil maize hybrids averages ∼8%, far lower than that in developed high-oil maize lines (as high as 20%). The maize seed/kernel consisted of endosperm (82%) and the germ (embryo and scutellum) (12%). The germ region makes up 80–84% of kernel oil, with the aleurone and endosperm making up 12% and 5%, respectively. High-oil maize may serve as a valuable forage maize germplasm for breeding. Maize oil is also considered as high-quality oil for human health due to the high proportion of polyun-saturated fatty acids. Selection for high oil increases the proportion of germ and further content of germ oil. The problems that over-shadow the successful production of high-oil corn are low grain yield potential, physiological cost of oil synthesis, low seed vigor, low kernel weight, shorter seed longevity, and poor germination of high-oil corn lines. It is necessary to make efforts to generate nested populations or use marker-assisted recurrent selection (MARS) to accumulate the advantageous quantitative trait loci (QTLs) in the pa-rental lines. The oil content of maize inbreeds and hybrids could be further improved with the use of transgenes, genomics, and metabolic engineering technologies in new insight for the development of high oil maize breeding and strategies.

VARIAÇÃO BIOMÉTRICA E REPRODUÇÃO DO BIVALVE Anomalocardia flexuosa (BIVALVIA; VENERIDAE) EM DIFERENTES ÁREAS DE PESCA

The bivalve Anomalocardia flexuosa is one of the main fishing resources utilized in artisanal fishing in northeastern Brazil. The objective of the study was to identify the reproductive and biometric variations in the A. flexuosa shell across different fishing areas in the estuary of the Goiana and Megaó rivers in Northeast Brazil, generating information to support strategies for its conservation. Three bimonthly sampling points were used, with P1 being characterized by manual fishing; P2 by more intensive fishing than P1, with the use of less potent fishing gear; and P3 by high-intensity fishing with tools that enhance the collection capacity, such as long-handled nets. For each specimen collected, shell length, shell height, shell width, total weight wet weight, and meat yield were measured to assess size patterns of the organisms and meat yield. Histological analyses were also conducted to identify the reproductive stages. From the analysis of 5,188 captured specimens, it was observed that with P3 presented the lowest body sizes, possibly reflecting overfishing at the site. Growth models were isometric for shell measurements and negative allometric for the length-weight relationship in P1 and P2, and positive allometric in P3. Photomicrographs were taken of 32 specimens for P1, withe 45% males, 48% females and 7% unidentified; and 25 specimens in P3, 12% males, 52% females and 36% unidentified. Regarding reproductive stages, the most representative were the “maturation” and “mature” stages. Due to the evidence of overfishing in P3 and high potential yield in other points, we highlight the need for efficient management actions that mitigate the impacts of overfishing, such as rotation of fishing areas.

Effects of Growth and Treatment Conditions on the Quality of Norway Spruce (Picea abies L.) Sawn Timber

A study was conducted to improve the effectiveness of silvicultural production of structural sawn timber from softwoods. It intends to explore prediction methods for mechanical timber quality. The study material was obtained from six stands divided into age groups of approximately 40- and 80-year-old trees (examining the influence of age). The stands were differentiated by their applied thinning system of thinning from below or above (examining the influence of the thinning system). Resulting from these different levels of data, i.e., stand parameters, tree anatomy, and visual board properties are examined and analyzed in ordinal logistic models and linear mixed models. Visual board properties were discerned by means of the German standard for visual grading of sawn timber. The mechanical board properties were measured in on-edge bending strength tests and allocated into strength classes, which were modeled in dependence of visual characteristics and forestry conditions. The evaluation of mechanical properties attributed a significant loss of timber quality to short rotation periods, non-ideal water supply, and a single-tree management system. The prediction capabilities of models based on site and tree characteristics were on par with the accuracy of visual grading. Management adaptations by intense thinning from above can lead to a significant decline in Norway spruce (Picea abies L.) timber quality when site factors coincide. Particular care should be taken in the management of locations with high yield potential. Non-destructive evaluation based on site characteristics combined with terrestrial laser scan data of tree characteristics has potential as a pregrading method.

Identification of quantitative trait loci of pod dehiscence in a collection of soybean grown in the southeast of Kazakhstan.

Soybean [Glycine max (L.) Merr.] is one of the important crops that are constantly increasing their cultivation area in Kazakhstan. It is particularly significant in the southeastern regions of the country, which are currently predominant areas for cultivating this crop. One negative trait reducing yield in these dry areas is pod dehiscence (PD). Therefore, it is essential to understand the genetic control of PD to breed new cultivars with high yield potential. In this study, we evaluated 273 soybean accessions from different regions of the world for PD resistance in the conditions of southeastern regions of Kazakhstan in 2019 and 2021. The field data for PD suggested that 12 accessions were susceptible to PD in both studied years, and 32 accessions, in one of the two studied years. The genotyping of the collection using a DNA marker for the Pdh1 gene, a major gene for PD, revealed that 244 accessions had the homozygous R (resistant) allele, 14 had the homozygous S (susceptible) allele, and 15 accessions showed heterozygosity. To identify additional quantitative trait loci (QTLs), we applied an association mapping study using a 6K SNP Illumina iSelect array. The results suggested that in addition to major QTL on chromosome 16, linked to the physical location of Pdh1, two minor QTLs were identified on chromosomes 10 and 13. Both minor QTLs for PD were associated with calmodulin-binding protein, which presumably plays an important role in regulating PD in dry areas. Thus, the current study provided additional insight into PD regulation in soybean. The identified QTLs for PD can be efficiently employed in breeding for high-yield soybean cultivars.