Genetic Improvement Programs Research Articles

Genetic Diversity of Rice Genotypes Screened under Normal and Flash Flooded Condition

The present investigation was undertaken to explore the extent of diversity in 30 rice genotypes under normal (E1) and flash flooded conditions (E2) during samba, 2020. Analysis of variance divulged significant variability with respect to all the nine traits viz., days to 50% flowering, plant height, number of productive tillers per plant, panicle length, number of grains per panicle, 1000 grain weight, grain length, grain breadth and grain yield per plant under study. Mahalanobis D2 values and non- hierarchical Euclidean cluster analysis categorized into seven clusters in E1 and three clusters in E2. The maximum intra cluster D2 was obtained in cluster V (80.618) in E1 and III (1626.542) in E2 and farthest inter cluster distance between III and cluster VI (129.797) in E1, cluster II and III (2743.060) in E2. The clusters VI and II exerted superior mean performance in E1 and cluster III and II had in E2. The characters viz., number of grains per panicles, panicle length, number of productive tillers per plant, grain breadth along with grain yield per plant were the major contributors for genetic divergence in E1. In the flash flood tolerance environment E2, the traits of plant height, grain breadth, and grain yield per plant contributed more toward the genetic divergence. Based on genetic diversity and performance of the genotypes Poongar, seeraga samba, CR 1009 sub1 and Swarna sub 1 are the superior parents for flash flood tolerance. Hence, these genotypes could be lucidly utilized for the flash flood genetic improvement program.

Farmer perspectives on desired catfish attributes in aquaculture systems in Nigeria. An exploratory focus group study

As a first step to determine the focus of potential genetic improvement programs for African catfish in Nigeria, we conducted a study to identify the preferred attributes among catfish producers across three states renowned for aquaculture production, in December 2022. Employing a qualitative approach, data were collected through 11 focus group discussions involving 122 participants. The findings indicate that farmers prioritize a range of catfish attributes related to both consumption and production. The top five production-related attributes identified by farmers include stress tolerance, disease resistance, fast growth, robustness, and high survival rates. For consumption-related attributes, preferences were for large, long, heavy catfish, with abundant flesh and thickness. Notably, the prioritization of these attributes varied among catfish farmers both between and within states, reflecting diverse farming objectives and market dynamics. Future research is essential to define precise objectives and scope for selective breeding program design, considering the investment necessary for the success of such programs and how they can accommodate the diverse preferences identified.

Molecular Genetic Diversity of Manioc (Manihot esculenta Crantz) Using Simple Sequence Repeated Markers (SSR) in the Kara Region of Togo

Cassava (Manihot esculenta Crantz), a plant of the future, is one of the main crops with high genetic potential. Therefore, the knowledge of its genetic variability would be of great importance for its effective use in genetic improvement programs. The objective of this work was to characterize the genetic diversity of cassava cultivars present in the Kara region of Togo. Thus, a total of 91 cassava leaf samples collected in the 7 prefectures of the Kara region were analyzed using 7 pairs of SSR microsatellite primers. Fifty-three alleles were detected with an average of 7.57 alleles per locus. The polymorphic information content ranged from 0.63 to 0.83 with an average of 0.74, indicating a high level of marker polymorphism. Molecular analysis of variance revealed that the majority of variability occurred within individuals and accounted for 99 % of the total variation between individuals. Weak genetic differentiation (Fst=0.011) was also observed between populations. The genetic structuring model based on the Neighbour-Joining algorithm method divided the individuals into 6 groups independently of local names. These results indicate the presence of high genetic resource variability in the studied populations. Therefore, it would be important to implement management strategies to better conserve cassava genetic resources and to facilitate the identification of successful cultivars.

Investigating growth associated genomic short tandem repeats (STRs) in a resource population generated through molecular breeding of RIR chicken

The long-term selection based on phenotypes causes loss of variation in performance traits and slows down the genetic progress per generation in the population; genomic selection could restore the variability along with faster genetic progress. Genomic short tandem repeats (STRs) in a resource population of RIR chicken were explored investigating randomly selected 114 pedigreed chicks. Alleles separated through 3.4% MetaPhor agarose gel electrophoresis at ten STR loci, and data recorded on growth traits were analyzed. Twenty-six alleles were resolved with frequencies of 0.1140–0.7632 and > 38.60% for the most frequent alleles at ten STR loci. The most frequent genotypes appeared with frequency >21.93% at different loci. Polymorphic information contents ranged from 0.2961 (LEI0079) to 0.6716 (LEI0071). Effective number of alleles ranged from 1.5662 (LEI0079) to 3.5836 (LEI0071). Mean FIS statistics revealed overall 21.78% heterozygosity deficit. Average heterozygosity ranged from 0.3630 (LEI0079) to 0.7241 (LEI0071). Chi-square and G-square test showed the population in Hardy-Weinberg disequilibrium at nine loci. Chick weight was significantly influenced by the factor of sire, and body weight traits by sex and hatch factors of the birds coded with STR-genotypes. ADL0328-BB genotype had the highest chick weight. LEI0068-BC and LEI0071-CC genotypes showed maximum 28-weeks body weight. MCW0010-AA genotype had the potential bearing of the highest body weight records at 16, 32, 36 and 40 weeks of age. MCW0058-CC genotype revealed the same at 24 and 28 weeks of age. The study impacts on marker assisted selection program for genetic improvement of growth traits in poultry.

Towards Sustainability in Seed Supply for African Catfish, Clarias gariepinus (Burchell, 1822) Culture in Kenya: Lessons from Asian Catfishes Industry

The culture of African catfish, Clarias gariepinus, is constrained by the high mortality of fry, occasioning a shortage of high-quality seeds for stocking by farmers. Asia, a continent with many success stories for aquaculture, leads in farmed production of some catfishes, a diverse group of 37 different families. Globally, the culture of catfishes ranks fifth in global farmed finfish production. Globally, Vietnam leads in the production and export of farmed striped catfish, Pangasianodon hypophthalmus, with 1,400,000 tonnes produced annually from about 7,000 hectares. Similarly, China farmed the non-native Channel catfish, Ictalurus punctatus, into the major crop, with a current annual production of 250,000 tonnes. On the contrary, C. gariepinus, the main farmed catfish species in Africa, records low annual yields, with 240,000 tonnes for the whole continent. This paper explores the factors behind the high production of P. hypophthalmus and I. punctatus in Vietnam and China, respectively, and draws lessons for C. gariepinus farmers in Africa. Specifically, the use of differentiated hatchery and nursery husbandry practices was critical in boosting seed production, quantity, availability, and distribution for expanding the culture of P. hypophthalmus in Vietnam. Improvement of fish species through well-designed genetic improvement programs helped China substantially increase production of I. punctatus. For both species, intensive fish production, as well as the adoption and implementation of suitable policies, increased seed production from hatcheries in both countries. These are discussed as some of the factors that spurred catfish production in the two Asian countries. We argue that if these are adopted by farmers in Africa, they could help improve the production of farmed C. gariepinus on the continent for food and nutrition security as well as generation of livelihood for local communities.

Phytoene Desaturase (PDS) Gene-Derived Markers Identify “A” and “B” Genomes in Banana (Musa spp.)

Phytoene desaturase (PDS) is a plant enzyme involved in carotenoid biosynthesis. The PDS gene has been used as a selective marker for genome editing in several plant species, including banana (Musa spp.). Its knockout promotes dwarfism and albinism, characteristics that are easily recognizable and highly favorable. In Musa spp., the A genome increases fruit production and quality, whereas the B genome is associated with tolerance to biotic and abiotic stresses. The objective of this study was to identify a molecular marker in the PDS gene to easily discriminate the A and B genomes of banana. A 2166 bp fragment for the “PDSMa” marker was identified as polymorphic for the A genome (identification accuracy of 99.33%), whereas ~332 and ~225 bp fragments were detected for the “PDSMb” marker with 100% accuracy using MedCalc software. In this study, we used genotypes with A and B genomes that are used in the genetic improvement of bananas and an accession with the BT genome. It was not possible to differentiate the accession with the BT genome from the others, suggesting that the markers do not have the capacity to separate the T genome from the A and B genomes. To the best of our knowledge, this is the first study to use the PDS gene to determine doses of the A genome and identify the B genome in Musa spp., which will aid in evaluating the genomic constitution of banana hybrids and accessions at the seedling stage and accelerating their classification in crop genetic improvement programs.

Genotype x Environment Interaction and Stability Analysis for Seed Yield in Desi Chickpea (Cicer arietinum L.) under Irrigated Condition

Background: Chickpea is mainly grown on marginal lands and encounter the problem of erratic rainfall that causes lack of water availability especially at terminal growth stages. Exploration of yield stability and defining the adaptation domains of advance genotypes in different ecosystem is highly imperative for crop genetic improvement programs. Development of variety with high yield potential and stable under irrigated condition is one of the major objectives of chickpea improvement programme, which can be achieved by improving selection efficiency with estimating stability parameters. Ten chickpea genotypes as advance breeding lines and popular varieties were evaluated to assess seed yield stability under irrigated condition during rabi 2021-22. Methods: Experiments were conducted in randomized block design with three replications at five different locations of Karnataka i.e. Bidar, Kalaburagi, Bheemarayanagudi, Raichur and Hagari. The interaction analysis (AMMI ANOVA) indicates large variations for seed yield due to highly significant (p less than 0.01) environment (65.42%) and significant (p less than 0.05) genotype (10.03%), thus the genotypes were diverse with large sum of squares for seed yield and environment. Result: The differential response of chickpea genotypes for seed yield across the environments was observed. IPCA1 and IPCA2 together captured 12.97 per cent of the interaction mean squares RG-2016-134 and KCD-2019-05 showed higher mean yields and adaptable to favourable environments. Based on AMMI bi-plot analysis, genotypes (KCD-2019-05 and Super Annigeri-1) were stable and (DC-17-1111 and RG-2016-134) were unstable. Similarly, best performer genotypes and three mega environments were noticed through the analysis. Three environments i.e., (Bidar, Kalaburagi and Raichur) were found with most selective for seed yield estimation. The genotypes (RGV-203, KCD-2019-02 and Super Annigeri-1) were the best among all the ten tested genotypes in terms of seed yield stability.

Landscape genomics reveals regions associated with adaptive phenotypic and genetic variation in Ethiopian indigenous chickens.

Climate change is a threat to sustainable livestock production and livelihoods in the tropics. It has adverse impacts on feed and water availability, disease prevalence, production, environmental temperature, and biodiversity. Unravelling the drivers of local adaptation and understanding the underlying genetic variation in random mating indigenous livestock populations informs the design of genetic improvement programmes that aim to increase productivity and resilience. In the present study, we combined environmental, genomic, and phenotypic information of Ethiopian indigenous chickens to investigate their environmental adaptability. Through a hybrid sampling strategy, we captured wide biological and ecological variabilities across the country. Our environmental dataset comprised mean values of 34 climatic, vegetation and soil variables collected over a thirty-year period for 260 geolocations. Our biological dataset included whole genome sequences and quantitative measurements (on eight traits) from 513 individuals, representing 26 chicken populations spread along 4 elevational gradients (6-7 populations per gradient). We performed signatures of selection analyses ([Formula: see text] and XP-EHH) to detect footprints of natural selection, and redundancy analyses (RDA) to determine genotype-environment and genotype-phenotype-associations. RDA identified 1909 outlier SNPs linked with six environmental predictors, which have the highest contributions as ecological drivers of adaptive phenotypic variation. The same method detected 2430 outlier SNPs that are associated with five traits. A large overlap has been observed between signatures of selection identified by[Formula: see text]and XP-EHH showing that both methods target similar selective sweep regions. Average genetic differences measured by [Formula: see text] are low between gradients, but XP-EHH signals are the strongest between agroecologies. Genes in the calcium signalling pathway, those associated with the hypoxia-inducible factor (HIF) transcription factors, and sports performance (GALNTL6) are under selection in high-altitude populations. Our study underscores the relevance of landscape genomics as a powerful interdisciplinary approach to dissect adaptive phenotypic and genetic variation in random mating indigenous livestock populations.

Organogenesis of Plant Tissues in Colchicine Allows Selecting in Field Trial Blueberry (Vaccinium spp. cv Duke) Clones with Commercial Potential

Plants’ genetic improvement continues to be crucial for modern agriculture, while biotechnology can offer efficient tools that enhance the selection and recommendation processes of elite clones. This work established a suitable methodology for the regeneration of blueberry (Vaccinium corymbsum) plants in cultures with colchicine. This could be considered a basis for producing populations for the selection of clones following a genetic improvement program assisted by biotechnology. The factors studied were: (a) explant type (leaf discs; nodal segments); (b) colchicine concentration (0, 0.5, 1, and 2 mg/L); and (c) time of exposure to colchicine (1, 2, 3, 5, and 30 days). The basal medium McCown’s Woody Plant (WP) supplemented with 2 mg/L 2iP and 1 mg/L BAP was used with the commercial genotype Duke as a model. A total of 1957 blueberry clones were produced in a medium with 1 mg/L colchicine, distributed at different exposure times. Flow cytometry analyses revealed the following patterns: single patterns for random samples of control plants (Duke donor) and some clones regenerated on colchicine; double patterns for chlorotic plants regenerated on colchicine. Triple and quadruple patterns were observed in callus tissues that did not regenerate plants on colchicine. Populations of plants regenerated in colchicine (6787) and control plants regenerated in in vitro culture without colchicine were adapted under greenhouse conditions. The variables evaluated at this stage were adaptability, height, diameter, number of leaves, incidence of diseases, flowering capacity, and agrobotanical traits. Selected clones demonstrating phenotypic variability (157 clones) were transplanted to field conditions. From the clonal field trial conducted under minimum tillage conditions, 38 clones were selected for improved traits related to the agricultural yield and nutritional quality of the fruits. Of these, six clones showed the highest agronomic performance and adaptability to adverse environmental conditions compared to the Duke donor genotype. It is recommended that these clones continue genotype × environment interaction trials at different locations.

UAV-driven GWAS analysis of canopy temperature and new shoots genetics in slash pine

Canopy temperature and new shoot counts are pivotal traits for evaluating the adaptability and productivity of slash pine (Pinus elliottii Engelm.). Traditional methods for assessing these traits are labor-intensive and lack the required accuracy. Despite their ecological and economic importance, the genetic and molecular underpinnings of these traits remain largely unexplored. In this study, we utilized UAV remote sensing technology for conducting high-throughput phenotyping of canopy temperature and new shoot counts and performed a Genome-Wide Association Study (GWAS) to identify key candidate genes associated with these traits. Our Manhattan plot analysis revealed intriguing patterns. The GWAS analysis of both July and August identified the same four key candidate genes for new shoot counts including scaffold119881_56626, scaffold119881_56642, scaffold96999_96025, and scaffold7133_48553 respectively. However, for canopy temperature, no key candidate genes were identified in the overall monthly analysis. Interestingly, diurnal variations in canopy temperature influenced the identification of key genes. While no key genes were identified during the afternoon and evening, two were found in the morning: scaffold33143_278946 and super3157_662643. Our UAV-based approach proved to be highly accurate and portable, with significant heritability estimates for both traits. This study represents the first GWAS analysis on these traits and underscores the importance of integrating high-throughput phenotyping and genotyping technologies for advancing forest genetic improvement programs, particularly in the selection of key candidate genes influenced by diurnal and monthly variations.

Nutritional Characterization of Chilean Landraces of Common Bean

Common bean (Phaseolus vulgaris L.) is the primary grain legume cultivated worldwide for direct human consumption due to the high nutritional value of its seeds and pods. The high protein content of common beans highlights it as the most promising source of plant-based protein for the food industry. Additionally, landraces of common bean have great variability in nutritional traits, which is necessary to increase the nutritional quality of elite varieties. Therefore, the main objective of this study was to nutritionally characterize 23 Chilean landraces and 5 commercial varieties of common bean to identify genotypes with high nutritional value that are promising for the food industry and for genetic improvement programs. The landrace Phv23 (‘Palo’) was the most outstanding with high concentrations of minerals such as P (7.53 g/kg), K (19.8 g/kg), Mg (2.43 g/kg), Zn (52.67 mg/kg), and Cu 13.67 mg/kg); essential amino acids (364.8 mg/g protein); and total proteins (30.35 g/100 g seed). Additionally, the landraces Phv9 (‘Cimarrón’), Phv17 (‘Juanita’), Phv3 (‘Araucano’), Phv8 (‘Cabrita/Señorita’), and Phv4 (‘Arroz’) had a high protein content. The landrace Phv24 (’Peumo’) stood out for its phenolic compounds (TPC = 218.1 mg GA/100 g seed) and antioxidant activity (ORAC = 22,167.9 μmol eq trolox/100 g extract), but it has moderate to low mineral and protein concentrations. In general, the concentration of nutritional compounds in some Chilean landraces was significantly different from the commercial varieties, highlighting their high nutritional value and their potential use for the food industry and for genetic improvement purposes.

Genetic linkage map construction and QTL analysis for plant height in proso millet (Panicum miliaceum L.).

A genetic linkage map representing proso millet genome was constructed with SSR markers, and a major QTL corresponding to plant height was mapped on chromosome 14 of this map. Proso millet (Panicum miliaceum L.) has the lowest water requirements of all cultivated cereal crops. However, the lack of a genetic map and the paucity of genomic resources for this species have limited the utility of proso millet for detailed genetic studies and hampered genetic improvement programs. In this study, 97,317 simple sequence repeat (SSR) markers were developed based on the genome sequence of the proso millet landrace Longmi 4. Using some of these markers in conjunction with previously identified SSRs, an SSR-based linkage map for proso millet was successfully constructed using a large mapping population (316 F2 offspring). In total, 186 SSR markers were assigned to 18 linkage groups corresponding to the haploid chromosomes. The constructed map had a total length of 3033.42 centimorgan (cM) covering 78.17% of the assembled reference genome. The length of the 18 linkage groups ranged from 88.89cM (Chr. 15) to 274.82cM (Chr. 16), with an average size of 168.17cM. To our knowledge, this is the first genetic linkage map for proso millet based on SSR markers. Plant height is one of the most important traits in crop improvement. A major QTL was repeatedly detected in different environments, explaining 8.70-24.50% of the plant height variations. A candidate gene affecting auxin biosynthesis and transport, and ROS homeostasis regulation was predicted. Thus, the linkage map and QTL analysis provided herein will promote the development of gene mining and molecular breeding in proso millet.

Histological, immunohistochemical and serological investigations of the ovary during follicular phase of estrous cycle in Saidi sheep

BackgroundSaidi sheep are the most abundant ruminant livestock species in Upper Egypt, especially in the Assiut governorate. Sheep are one of the most abundant animals raised for food in Egypt. They can convert low-quality roughages into meat and milk in addition to producing fiber and hides therefore; great opportunity exists to enhance their reproduction. Saidi breed is poorly known in terms of reproduction. So this work was done to give more information on some hormonal, oxidative, and blood metabolites parameters in addition to histological, histochemical and immunohistochemical investigations of the ovary during follicular phase of estrous cycle. The present study was conducted on 25 healthy Saidi ewes for serum analysis and 10 healthy ewes for histological assessment aged 2 to 5 years and weighted (38.5 ± 2.03 kg).ResultsThe follicular phase of estrous cycle in Saidi sheep was characterized by the presence of ovarian follicles in different stages of development and atresia in addition to regressed corpus luteum. Interestingly, apoptosis and tissue oxidative markers play a crucial role in follicular and corpus luteum regression. The most prominent features of the follicular phase were the presence of mature antral (Graafian) and preovulatory follicles as well as increased level of some blood metabolites and oxidative markers. Here we give a new schematic sequence of ovarian follicles in Saidi sheep and describing the features of different types. We also clarified that these histological pictures of the ovary was influenced by hormonal, oxidative and blood metabolites factors that characterizes the follicular phase of estrous cycle in Saidi sheep.ConclusionThis work helps to understanding the reproduction in Saidi sheep which assist in improving the reproductive outcome of this breed of sheep. These findings are increasingly important for implementation of a genetic improvement program and utilizing the advanced reproductive techniques as estrous synchronization, artificial insemination and embryo transfer.

Methods for inoculation and evaluation of resistance to Macrophomina phaseolina in soybean genotypes

AbstractCharcoal rot, caused by Macrophomina phaseolina, is a disease of economic significance in soybean production. The evaluation of this disease is difficult due to the lack of reliable and efficient methods for testing soybean genotypes. This work aimed at investigating different inoculation methods for Macrophomina phaseolina in soybean genotypes to determine the degree of resistance and their use in genetic improvement programs. Infected sorghum seeds, pregerminated seed in culture medium, and infected toothpick test were the methods tested. Colonization by the fungus, determined as a colony‐forming unit (CFU), and disease development based on root and stem severity (RSS) were evaluated. There was a good correlation between CFU and RSS (0.87), with the infected sorghum seed method being the most efficient means of inoculating. The results show that PI594302 was the most resistant line regarding the two studied parameters and would be a source of resistance to charcoal rot in breeding programs.

Adaptation of basil to salt stress: Molecular mechanism and physiological regulation

Although many molecular and physiological mechanisms behind plant responses to osmotic and nutritional stresses (primarily salinity) have been identified, the strong impact of genetics makes understanding their interconnections complex. Moreover, the dominant genetic effect often masks other potentially influential factors modulating plant response to environmental stimuli. Using three types of basil (Dark Opal, Italiano Classico, and Purple Ruffles) that have different counteracting potentials to react to NaCl (60 mM) salt stress, we showed that higher constitutive concentrations of osmolytes and antioxidant molecules improve basil adaptation to a saline environment. An already active ROS scavenging mechanism and unaltered NUE allowed Purple Ruffles to remain unaffected by the toxic effects of salt, unlike Italiano Classico and Dark Opal, which incurred fresh yield reduction by 46.34 and 33.33 %, respectively. Up-regulation of secondary metabolism in response to biostimulant treatments (protein hydrolysate and protein hydrolysate+leaf liquid integrator) ensured a higher fresh yield in all basil types, regardless of salt treatment. Understanding the key molecular traits implicated in plant response to salinity is undoubtedly valuable for future genetic improvement programs of tolerant genotypes and for the application of products with biostimulatory and ameliorative action.

Genetic Assessment of Leucaena leucocephala (Lam.) de Wit Provenances by Using ISSR Markers

Inter Simple Sequence Repeats (ISSR) technique was deployed for the estimation of genetic diversity in18 Leucaena leucocephala provenances. Seeds of these provenances were collected from across the country and planted at a single location in South India. To estimate the genetic diversity/ polymorphism, DNA was extracted through Cetyl Trimethyl Ammonium Bromide (CTAB) method, visualized and analyzed the DNA bands on UV trans- illuminator gel doc (α-imager 3.2). Totally ten ISSR primers were used in this study. Among them, eight ISSR microsatellites showed a high degree of polymorphism in all the eighteen leucaena provenances used in our study. These primers successfully amplified a total of 645 bands, of which 577 bands (89 %) showed polymorphism. On average, 14.92 bands per accession were obtained and 68.28 % provenances were distinguished through these primers. The ISSR primer T(GT)9 was able to distinguish 100 % of the L. luecocephalla provenances. Cluster analysis based on the genotypic similarities assembled the 18 leucaena accessions in to three clusters. The dendrogram generated based on the 8 ISSR primers distinctively demarcated many of the L. leucocephalla accessions into different clusters indicating vast genetic diversity among the provenances. The high degree of genetic variability demonstrated by the ISSR molecular markers in L. leucocephalla can be used as a tool for assessing genetic diversity and in future leucaena genetic improvement programs.

Aromatic rice (Oryza sativa L.) landraces of Indo‐Gangetic Plains of India harbor rich genetic diversity

AbstractAromatic rice (Oryza sativa L.) germplasm conserved in global genebanks needs intensive characterization to assess genetic diversity and population structure for crop improvement. We analyzed a panel of 92 accessions of non‐Basmati aromatic rice landrace germplasm with 23 phenotypic traits and 48 microsatellite markers. The landrace accessions displayed a huge phenotypic diversity for traits, namely, culm length, flag‐leaf length, panicle‐bearing tillers (PBT), plant height, panicle length, peduncle length, panicle exsertion, grain length, grain width, hull color, and 1000‐grain weight (TGW). Phenotypic clustering revealed three major clusters and five principal components explained 81.24% of the variance. TGW was associated positively with grain length, grain width, peduncle length, and grain yield but negatively with culm length and PBT. A total of 528 microsatellite alleles were detected, with 11.0 alleles per locus, revealing the presence of high polymorphism. Genetically, four subpopulations were detected based on structure analysis. In the germplasm, high levels of gene flow (Nm = 1.51) and gene diversity (HE = 0.83) were found. Among the subpopulations, we discovered high levels of inbreeding (FIS = 0.92) and moderate genetic differentiation (FST = 0.14). High polymorphism information content (0.806) along with a high level of molecular variance among genotypes (79%) was detected. A large number of multiple alleles were detected in numerous landrace accessions, revealing the presence of heterogeneity and heterozygotes in the landrace germplasm. The results of the present study are vital for the utilization of landrace diversity in the genetic improvement programs designed for rice quality improvement and consumer preference.

Genomic inbreeding estimated through runs of homozygosity in Moura pigs and four commercial swine breeds

The transmission of identical haplotypes from a common ancestor creates long stretches of homozygous genotypes, known as runs of homozygosity (ROHs). Longer haplotypes are inherited from recent common ancestors, and shorter haplotypes, from distant ancestors. In this study, we performed a comparative analysis of the genomic data of the Moura pig breed, a locally adapted breed from Brazil, that typically grows in extensive or semi-intensive systems, in comparison to the commercial breeds Duroc, Landrace, Large White, and Pietrain. We investigated ROH patterns and different inbreeding coefficients in order to guide long-term breeding programs, rescue efforts, and breed evaluation programs. To understand these patterns, we performed a detailed genome characterization of 459 animals, of which 84 were Moura, 87 Duroc, 138 Landrace, 84 Large White and 66 Pietrain swine, performed using Illumina Porcine v2 BeadChip markers. Inbreeding coefficients based on the genomic relationship matrix and ROH were calculated, indicating that Moura pigs displayed the highest ROH frequency (greater than 8 Mb) compared to the other swine breeds. This demonstrates that Moura pigs exhibit greater inbreeding in recent generations, probably due to severe reductions in the number of animals. Furthermore, genes related to meat quality were detected on the ROH islands superimposed on the Moura and Duroc breeds, comprising one of the main characteristics of both breeds. Kinship analysis revealed notable genetic diversity among Moura pigs, with the majority of comparisons indicating the absence of direct parentage. Our findings contribute to a better understanding of the genomic profile of the locally adapted Moura breed. Additionally, they underscore the importance of monitoring inbreeding as a starting point for genetic improvement programs and genomic studies of this breed.

First Record of Mythimna sequax (lepidoptera: noctuidae) damaging canary grass (Phalaris canariensis) in Ijuí, RS, Brazil

Canary grass (Phalaris canariensis L.) is a plant belonging to the Poaceae family, exhibiting a production cycle like the main winter cereals cultivated in Rio Grande do Sul. In pursuit of this market, the Regional University of Northwestern State of Rio Grande do Sul, through the Genetic Improvement Program – Grain and Cover Plants line, has successfully undertaken initiatives to enhance canary grass cultivation. This involves improving cultivars and adopting technologies to maximize productivity, with the aim of providing cultivars better adapted to the northwestern region of the state to meet the needs of local producers. In this sense, this research stands as the inaugural report of the pest in Ijuí, RS, Brazil, specifically targeting canary grass, offering valuable insights into its life stages, and providing a foundation for future studies on Mythimna sequax.

Early Cannon Development in Females of the "Sanmartinero" Creole Bovine Breed.

The variation in the dimensions of the body of living beings in relation to their size, function, or shape is known as allometry. Allometry studies allow the analysis of the function of body structures and their relationship with the performance and survival of breeds and species. The aim of this study was to describe the ontogenetic characteristics of the weight of certain bone elements of the Sanmartinero creole bovine breed, from an early age (6 months) until maturity. A total of 79 females of the Sanmartinero creole bovine breed with an age range of 0.5 to 10 years were studied. Body measurements were obtained individually using standard procedures: cannon perimeter, thoracic perimeter, body length, withers height, and body weight. Functional and production indices were obtained for animals aged more than 3 years (n = 53): corporal index, anamorphosis index, dactylo thoracic index, and the relative thickness of the cannon. The correlation between body weight and the cannon perimeter showed no trend towards a plateau. In the Sanmartinero creole bovine, therefore, a very early development of the cannon perimeter is detected, which could lead to bone fragility in heavier animals. Therefore, data suggest little harmony with appendicular bone development, i.e., with less robust cannons which are those necessary to support body mass. It is suggested that in genetic improvement programs of the Sanmartinero creole bovine, the measurement of the cannon perimeter, the withers height, and the thoracic perimeter should be considered.