Desirable Genotypes Research Articles

Strategies for identification of elite Hevea brasiliensis genotypes tolerant to ALF disease from half-sib and full-sib population

Natural Rubber (NR) from Hevea brasiliensis tree is an important commercial commodity worldwide. In general, many Hevea cultivars are vulnerable to abnormal leaf fall (ALF) disease caused by Phytophthora spp., which can lead to considerable reduction in crop production. Chemical control of ALF by spraying mineral oil-based copper fungicides is the conventional approach which is harmful to the ecosystem. Development of ALF tolerant varieties of Hevea through conventional breeding is the major objectives of this study. We evaluated the primary agronomy traits and ALF tolerance level of the newly developed Hevea clones using in vitro leaf disc bioassay as well as field screening for disease incidence consecutively for three years. Variation in disease infestation was observed among genotypes. Based on field screening, the clones which showed better field tolerance against ALF than the parental clones were selected. Clone 683 was identified as one of the most desirable genotypes which had vigorous growth as well as high crop yield in addition to ALF tolerance. The study also confirms the reliability of in vitro leaf disc bioassay technique for screening against ALF across genotypes for its inherent variability. This technique is rapid and easier and can be completed within 96 hours. This approach could reduce the burden of screening larger breeding population to a manageable size to enhance the efficiency of selection in ALF disease resistance breeding programs. Selected fast growing, high yielding ALF tolerant clones, could be further evaluated in on farm trials for recommending to the growers in the traditional region of rubber growing tracts.

Genetic diversity and polymorphism of genes associated with meat quality and growth traits of A Luoi Yellow cattle in Vietnam

Background and Aim: A Luoi Yellow cattle is an indigenous cattle breed that is raised in the A Luoi District, Vietnam, characterized by its small body size, high adaptability, and meat quality favored by domestic consumers. Marker-assisted selection is an effective approach for improving breeding genetics and sustainably developing livestock production. Therefore, this study aimed to investigate the genetic diversity and polymorphism of genes associated with meat quality and productivity in the A Luoi Yellow cattle population with the goal of future breeding selection and sustainable development of the A Luoi Yellow beef brand. Materials and Methods: In this study, we genotyped six functional genes, including Leptin (LEP), Calpastatin (CAST), Calpain 1, pleomorphic adenoma gene 1, Sirtuin 1, and Sirtuin 2 (SIRT2), involved in meat quality and growth traits using polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphis. We also investigated mitochondrial DNA (mtDNA) and the Y chromosome-specific gene on the Y chromosome to elucidate the genetic diversity and paternal and maternal origin of the A Luoi Yellow cattle using Sanger sequencing. Results: The results showed that A Luoi yellow cattle have Bos indicus origin from both paternal and maternal lineages. By mtDNA analysis, we identified two new haplotypes of the I1 haplogroup that were not previously detected. The genotyping of the six functional genes indicated that A Luoi Yellow cattle carry favorable alleles that increase meat tenderness and body size, with frequencies of 0.02–0.40. In particular, the presence of desirable homozygous genotypes of the CAST, LEP, and SIRT2 genes will be important for the future selection of animals based on their potential performance in meat quality and productivity. Conclusion: The findings of this study is useful for the future breeding and sustainable development of A Luoi Yellow cattle. Keywords: A Luoi yellow cattle, growth trait, indels, meat tenderness, single nucleotide polymorphisms.

ОЦЕНКА КОРОВ-ПЕРВОТЁЛОК ЧЁРНО-ПЁСТРОЙ ПОРОДЫ ПО ДНК-МАРКЕРАМ, АССОЦИИРОВАННЫХ С ХОЗЯЙСТВЕННО-ПОЛЕЗНЫМИ ПРИЗНАКАМИ

At present time are widely used genetic markers as means in the selection of highly productive animals. Since the genes: CSN3 (kappa-casein), PIT-1 (pituitary-specific transcription factor), PRL (prolactin), GH (somatotropin) are polymorphic and encode various proteins, the study of their influence on the productive traits of cattle is relevant. In this regard, the goal of the work is to determine the influence of complex genotypes of the studied genes on the milk productivity of first-calf cows of the Black-and-White breed bred in the collective farm-breeding plant «Kazminsky» in the Kochubeevsky district of the Stavropol Territory. The place of research is the Department of Genetics and Biotechnology, VNIIOK, a branch of the North Caucasian Federal National Research Center. This article presents the results of DNA genotyping of allelic polymorphism for the CSN3, PIT-1, PRL, GH genes using PCR-RFLP methods in first-calf cows of the Black-and-White breed. It was established that these genes in the studied sample are polymorphic. The frequency of occurrence of the desired CSN3B allele in the studied sample was 0.23. The presence of alleles PIT-1A and PIT-1B of the pituitary-specific transcription factor gene was noted with a frequency of occurrence of 0.52 and 0.48. A feature of the PRL gene polymorphism was the fairly high frequency of occurrence of the PRLA allele (0.60). In this study sample of dairy cattle, the frequency of occurrence of the desired GHL allele of the somatotropin gene was 0.62. All variants of complex genotypes were also identified and their relationship with milk productivity in black-and-white cows was noted. The study sample was dominated by animals carrying complex desirable genotypes, consisting of four and three marker alleles of three and two genes (CSN3AB/PIT-1BB/GHLV; CSN3AB/PIT1AB/GHLL or PIT-1AB/PRLAB/GHLV; PIT-1AA/GHLL ) - 46.7 %. Milk yield per lactation between groups of black-and-white first-calf cows with different complex genotypes ranged from 5839.14 to 8611.33 kg. The mass fraction of fat in milk ranged from 3.93 to 4.04 %, and protein from 2.99 to 3.14 %.

Study of genotype × environment interaction on the morphological and chemical features of geranium (Pelargonium graveleons L'Her Ex Ait.)

Geranium is a multi-harvest perennial plant in the Geraniaceae family grown for its sweet-scented herbs and essential oils. It is well-known for its imposing rose-like aroma. Geranium essential oil is commonly used in the soap, fragrance, and cosmetic industries to isolate rhodinol, an aromatic compound found in most high-grade perfumes. The current study evaluated a total of 5 geranium genotypes across three years, at two locations, to identify the superior and stable geranium genotypes. "The pooled ANOVA results showed substantial genotype × environment interactions for all the traits under study. The CIM-Bio 171 genotype had the highest essential oil production per plant (g) (X9), followed by Kelkar (rank II, 10.24), Algerian CIM-Pawan (rank III, 10.03), CIM-Pawan (rank IV, 7.63), and Bourbon (rank V, 7.24) g/plant. For the trait citronellol content (X10), the Algerian genotype ranked top (37.83%), followed by CIM-Pawan (rank II, 30.81%), CIM-Bio 171 (rank III, 28.33%), Bourbon (rank IV, 26.89%), and Kelkar (rank V, 12.58%). The Kelkar genotype ranked the highest (6.20%) in the trait 10-epi-γ-Eudesmol content (X16), followed by CIM-Pawan (rank II, 5.89%), Algerian (rank III, 4.56%), Bourbon (rank IV, 4.29%), and CIM-Bio 171 (rank V, 4.25%). The genotype CIM Bio 171 exhibited the highest mean value for essential oil yield, and cis-Rose oxide content (%). The following genotypes, such as CIM Bio 171, Algerian, and CIM Pawan, emerged as high-mean performers and exhibited stability across diverse environments. The genotype CIM Bio 171 is closer to the ideal genotype, followed by CIM Bio 171, Algerian, and CIM Pawan as the most desirable genotypes. Similarly, the year Y3 was determined to be the most desirable based on GGE-biplot environment evaluations at both locations. Therefore, CIM Bio 171 has been released for commercial cultivation because of its exceptional performance in essential oil yield and quality attributes across locations and years. Kew wordscis-Rose oxide; essential oil; environment ranking; GGE-biplot; genotype × environment interaction.

Evaluation of sugarcane genotypes (Saccharum sp. hybrid) for multi-trait stability analysis across diverse environments

The current study evaluated a total of 21 sugarcane genotypes across 27 diverse environments, including nine locations over three cropping seasons, to identify the superior and stable sugarcane genotypes. The pooled ANOVA results showed substantial genotype-environment interactions among the 21 genotypes under study. The genotype Co 11015 exhibited the highest mean value for CCS yield, CCS percentage, and sucrose percentage. With the help of GGE analysis and biplots, both stable genotypes as well as mega environments were identified. The following genotypes such as Co 13014, Co 11015, Co 13018 and Co 14016 emerged as the high-mean performers and exhibited stability across diverse environments. The outcomes from ‘which-won-where’ patterns suggested the existence of different mega environments which are classified as ME1, ME2, and ME3. When the genotypes were ranked, it revealed that Co 14016 is closer to the ideal genotype, followed by Co 13014, Co 11015, and Co 13018 as the most desirable genotypes. Similarly, the environments E8, E25, and E26 were identified as the most desirable ones, based on GGE biplot environment rankings. The Multi-Trait Stability Index (MTSI) values highlighted the following genotypes such as Co 13018, Co 13003, and Co 11015 as stable ones with high performance across the traits and environments. The MGIDI (Multi-trait Genotype Ideotype Distance Index) values inferred that Co 11015, Co 15007, and Co 13018 are the superior genotypes. Consequently, Co 11015 was released for commercial cultivation based on its stability and superior performance for biomass yield and quality traits across the locations and environments.

Yield -based evaluation of low nitrogen tolerance indices for screening of [Sorghum bicolor (L.) Moench] genotypes

Nitrogen stress is one of the key factors limiting sorghum crop productivity. To identify desirable sorghum genotypes best suited to nitrogen stress, the response of 300 sorghum landraces and two standard checks: KS78, and BCK60 were evaluated using yield-based indices. The experiment was conducted under nitrogen stress and ideal conditions for two years using a split-plot in RCBD design with two replications. Nitrogen treatments were assigned to the main plots, and sorghum genotypes were assigned to the subplots. Fourteen nitrogen stress screening indices, namely, the yield stability index (YSI), stress tolerance index (STI), modified stress tolerance index (KSTI), low nitrogen tolerance index (LNTI), relative decrease in yield (RDY), tolerance index (TOL), yield index (YI), stress susceptibility index (SSI), stress susceptibility percentage index (SSPI), and harmonic mean (HM), were computed using grain yield. The yield under optimal and stress conditions was significantly positively correlated with the HM, MP, GMP, STI, HM, YI, and modified STI. The results from the cluster analysis, PCA biplot, and 3D biplot classified the genotypes into three groups: nitrogen stress tolerant, nitrogen stress susceptible, and poor performers under both environments. Using STI, GMP, and MP, Genotypes (G80) ETSL101255, (G216) ETSL101006, (G35) ETSL101258, (G146) ETSL100813, and genotypes (G244) ETSL100292, (G161) ETSL100539, (G240) ETSL100890, (G93) ETSL101845, (G261) ETSL100625, (G248) ETSL100874, (G258) ETSL100752, (G142) ETSL100921, (G135) ETSL100307 were identified as top nitrogen stress tolerant, and susceptible genotypes respectively. We conclude that the indices MP, GMP, and STI can help in improving sorghum yield by selecting nitrogen efficient genotypes.

Trait analysis of short duration boro rice (Oryza sativa L.) varieties in northern region of Bangladesh: Insights from heatmap, correlation and PCA

The role of genetic variation is utmost importance in the selection of a desirable genotype for breeding programs. In the northern region of Bangladesh, the performance of five short duration boro rice varieties (BRRI dhan28, BRRI dhan74, BRRI dhan81, BRRI dhan88, and Bangabandhu dhan100) on yield and yield-contributing traits were evaluated in four locations. Yield attributes tiller hill-1 (TN), panicle hill-1 (PN), filled grain panicle-1 (FG), panicle length (PL), 1000-grain weight (TGW), and harvest index (HI), showed a positive correlation with grain yield (GY). Conversely, spikelet sterility (SSP) and unfilled grains panicle-1 (UFG) showed negative associations with grain yield. Principal component analysis (PCA) revealed that the first three components accounted for 89.60% of variability. The highest positive eigenvalue was observed in DF, DM, BY, HI, PN, SY, TN, PL and GY in PC1, indicating their significant influence on the overall genotype variations. PC2 was primarily driven by plant height (PH) and FG, while PC3 driven by TGW and UFG. The results suggest that grain yield is highly influenced by FG, PH, DM, DF, PN, TN, PL, TGW, SY, BY, and HI. These components highlighted the importance in distinguishing rice genotypes with higher grain yield potential. By considering these traits, BRRI dhan74 have outperformed other varieties, followed by BRRI dhan88 and Bangabandhu dhan100. BRRI dhan74 is most suitable for all four location followed by BRRI dhan88. The traits such as PN, PL, FG, TGW, PH, & HI significantly influence rice yield and should be prioritized in breeding programs aimed at developing high-yielding rice varieties.

Performance Evaluation of Different Sorghum Genotypes (Sorghum bicolour (L.) Moench) Using GGE Bi-plot Stability Analysis

Sorghum (Sorghum bicolor (L.) Moench) is an important essential cereal crop in Ethiopia. Conversely, its productivity is low due to numerous biotic and abiotic factors. There are diverse and dynamic environmental conditions which needs detail and continue study on genotypes by environment interaction (GEI) to develop stable genotypes. The objective of this study was to determine the magnitude of GEI for grain yield of forty two sorghum genotypes and to identify stable and high yielding genotypes across locations. The experiments were laid out at three locations for two growing seasons using alpha lattice design with three replications. The plot size 5 m x 0.75 m x 2 rows (7.5 m<sup>2</sup>) and distance between block, replication, and plot was 1m, 1.5m, and 0.75m, respectively. Phonologic, agronomic, diseases and grain yield data were collected but only grain yield was used for stability analysis. The ANOVA revealed highly significant variation (p <0.01) among sorghum genotypes across locations and seasons. Mean grain yield of genotypes ranged from 1.29 to 3.69 with mean grain yield of 2.36, while environment range from 1.18 to 3.63 t/ha. The genotype G1 showed good performance across all test sites which range 5<sup>th</sup> at E1,3<sup>rd</sup> at E3 and E4, 15<sup>th</sup> and 7<sup>th</sup> at E5 and E6 and maximum grain yield was harvested from E3. Yield data were also analyzed using the GGE (that is, G, genotype +GEI, genotypes-by- environment interaction) bi-plot method. The first two principal components (PC1 and PC2) were used to create a 2- dimensional GGE bi-plot and explained 59.67 and 13.48 % of GGE sum of squares, respectively. GGE bi- plot identified G16, G4, and G1 high yielders and stable and G34 and G25 was the lowest yielding and least stable across locations. On the other hand, the environment E6, E4 and E1 were the most suitable to select desirable genotypes.

Genetic variability and path coefficient analysis among bread wheat (Triticum aestivum L.) genotypes for yield and yield‐related traits in bale highlands, southeastern Ethiopia

AbstractWheat (Triticum aestivum L.) is one of the most important strategic crops to overcome food security problems in the world including Ethiopia. This can be achieved through genetic improvement of the crop and its production practices. In this connection, information on the mutual association of traits is important for effective selection in wheat‐breeding programs. In 2021/2022 production year, a field experiment was undertaken to estimate the extent of genetic variability, path analysis, and association of yield and yield‐related characteristics for the selection of desirable wheat genotypes. A total of 64 bread wheat genotypes, including yellow rust‐resistant Boru (resistant), Hachalu (moderately resistant), and Madda‐Walabu (susceptible) as control, were used for the field experiment at Sinana and Agarfa Agricultural Research Centers. The experiment was laid out in a simple alpha lattice design. The mean analysis of variances showed highly significant differences (p < 0.001) for all traits among the tested genotypes. The value of the phenotypic coefficient of variance was higher than the genotypic coefficient of variance for all studied traits, indicating the presences of higher genetic variability among the tested genotypes. Grain yield had a significant positive correlation with days to maturity, grain‐filling period, plant height, kernels spike−1, thousand seed weight, and biological yield at both genotypic and phenotypic levels including spike length at phenotypic levels at both locations and with plant height, thousand seed weight, and biological yield at both locations at genotypic and phenotypic levels. Similarly, days to maturity and grain‐filling period also showed a significant positive phenotypic correlation with grain yield. The analyzed path coefficients at both genotypic and phenotypic levels also indicated how grain yield is influenced directly and indirectly by other yield and yield‐related traits. The result also showed the existence of good heritability values along with high genetic advance, higher phenotypic coefficient of variation and genotypic coefficient of variation for grain yield, biological yield, and grain‐filling period. This implies the true relationship among these traits and grain yield; therefore, due attention should be paid to such traits during selection for further improvement. Hence, the present study indicated the importance of the direct and indirect effects of the studied traits on yield and yield components which makes selection desirable for improving the grain yield of wheat and its genetic resistance against yellow rust in the study area.

Screening of Wheat Genotypes for Water Stress Tolerance Using Soil–Water Relationships and Multivariate Statistical Approaches

Drought stress constricts crop production around the world. Employing high-yielding cultivars with drought tolerance might be the ideal professional approach to coping with its detrimental outcomes. As a result, the current study was performed to investigate the sensitivity and tolerance of nine wheat genotypes to drought stress. In a randomized block design experiment, nine wheat genotypes were subjected to four water treatments: 100%, 85%, 70%, and 55% of the available water (AW). Four water regimes in two growing seasons were counted as eight environmental zones. The leaf’s water relations and photosynthetic pigment were estimated, as well as growth and yield parameters. Univariate and multivariate statistical approaches, including the new method of multi-trait genotype–ideotype distance (MGIDI), were used for evaluation. The analysis of variance revealed that genotype, environment, and their interactions had a highly significant effect on all traits. The same trend was shown by the additive main effects and multiplicative interaction (AMMI) analysis of variance for grain yield across the environments. The AMMI biplot study indicated that the G8 genotype is the most stable in terms of water stress. The G7 genotype can withstand droughts up to 55% of the available water, while the G8 and G3 genotypes can withstand droughts up to 70% of the available water. Based on all examined traits, this index was used to identify the stable genotypes G7, G8, and G3, which can therefore be suggested for cultivation during drought conditions. Furthermore, we found a positive correlation between the MGIDI, ANOVA, and tolerance index results, indicating that the same desirable genotypes of G7 and G8 were identified by these procedures as being highly tolerant and stable across a range of soil moisture conditions. Based on MGIDI analysis, we can recommend that the G7 genotype exhibits higher grain yield and yield-related traits with the best drought-tolerant indices.

Identification of new stable resistant sources and assessing agro-morphological performance of sponge gourd germplasm against Tomato Leaf curl New Delhi Virus incidence.

Tomato leaf curl New Delhi virus (TolCNDV) causes yellow mosaic disease, which poses a significant biotic constraint for sponge gourd cultivation, potentially resulting in crop loss of up to 100%. In the present investigation, 50 diverse genotypes were screened for 3 years under natural epiphytotic conditions. A subset of 20 genotypes was further evaluated across four different environments. The combined analysis of variance revealed a significant genotype × environment interaction. Eight genotypes consistently exhibited high and stable resistance in the preliminary screening and multi-environment testing. Furthermore, genotype plus genotype × environment interaction biplot analysis identified DSG-29 (G-3), DSG-7 (G-2), DSG-6 (G-1), and DSGVRL-18 (G-6) as the desirable genotypes, which have stable resistance and better yield potential even under diseased conditions. The genotype by yield × trait biplot analysis and multi-trait genotype-ideotype distance index analysis further validated the potential of these genotypes for combining higher yield and other desirable traits with higher resistance levels. Additionally, resistant genotypes exhibited higher activities of defense-related enzymes as compared to susceptible genotypes. Thus, genotypes identified in our study will serve as a valuable genetic resource for carrying out future resistance breeding programs in sponge gourd against ToLCNDV.

Genetic Characterization of Gardenia jasminoides Ellis Genotypes Derived from Seeds and Selection Based on Their Morphological Traits and Flower Aromatic Substances

Gardenia jasminoides Ellis is an evergreen shrub with white fragrant flowers, and it is cultivated for its ornamental, aromatic and medicinal value. The present study aimed to select desirable genotypes for potential commercial exploitation as pot plants or use in perfumery. Thus, 32 genotypes of G. jasminoides plants derived from seedlings, whose seeds were obtained from Australia and the USA, were evaluated for their genetic diversity in relation to four commercial cultivars (‘Pelion’, ‘Joy’, ‘Grandiflora’ and ‘Kimberly’, used as reference cultivars) using ISSR and SCoT markers. A cluster analysis separated the gardenia genotypes into the following three clusters: one cluster comprised the 16 genotypes originating from Australia, one included the 16 genotypes originating from the USA, and the third cluster contained the four reference cultivars. In other words, there was a clear demarcation of the genotypes investigated according to their geographical origin. In addition, the gardenia genotypes were evaluated for their morphological and chemical characteristics. Thus, flower- and leaf-related traits with ornamental value were measured, while the volatile compounds of flower extracts were identified with GC-MS analysis. Genotype 29-5 was selected for its acceptable morphological traits and genotype 51-8 for its rich volatile compounds. The major volatile compounds responsible for the floral aroma of the various gardenia genotypes examined were α-farnesene, benzyl tiglate, cis-3-hexenyltiglate, jasminelactone and linalool.

Applications of Molecular Marker Implementation for Enhanced Oilseed Breeding through Marker-Assisted Selection (Mas)

Oilseed crops are fundamental for various industrial and food purposes, necessitating advancements in breeding strategies to meet growing demands. Molecular markers and Marker-Assisted Selection (MAS) have emerged as powerful tools in oilseed crop improvement. This review explores the diverse applications of molecular markers and MAS in oilseed crops, highlighting their significance in enhancing breeding efficiency and genetic gains. The primary aim of this review is to provide a comprehensive overview of the application of molecular markers and MAS in oilseed crop breeding programs. Specifically, it aims to synthesize existing literature and case studies to elucidate the methodologies, advancements, and outcomes associated with the integration of molecular markers and MAS in oilseed crop improvement. The review highlights significant advancements in the application of molecular markers and MAS in oilseed crop breeding. Molecular markers have been extensively utilized for trait mapping, genetic diversity analysis, and selection of desirable genotypes with traits such as high oil content, disease resistance, and abiotic stress tolerance. Integration with conventional breeding methods has facilitated the development of elite oilseed crop varieties with improved agronomic performance and stress resilience. In conclusion, molecular markers and MAS represent valuable tools for accelerating oilseed crop breeding programs. Their integration has led to increased breeding efficiency, precision, and genetic gains. However, challenges such as marker validation, cost-effectiveness, and trait complexity remain to be addressed. Future research efforts should focus on refining marker technologies, enhancing trait mapping studies, and promoting the adoption of MAS in oilseed crop breeding to ensure sustainable production and global food security.

Assessment of Path Co-efficient Analysis for Yield and Yield Attributing Traits in Sponge Gourd [Luffa cylindrica (L.) Roem.

This investigation was conducted to determine the path coefficient analysis using 40 genotypes of sponge gourd at the experimental plot of Department of Vegetable Science, College of Horticulture, UHS, Bagalkot (Karnataka) in RBD design along with two replications during the year 2020-2021. Path co-efficient analysis considered as one of the best statistical methods which can help breeders to characterize the genotypes during the parent selection program and select the desirable genotypes for higher yield production. Path coefficients analysis showed thatthe traits like number of fruits per vine, average fruit weight, fruit length, number of branches per vine and vine length had positive direct effect on fruit yield per vine. Thus the higher magnitude of positive direct effect of these traits explains the higher value of association between these traits on yield per vine. Therefore, direct selection for these traits would reward for yield improvement in sponge gourd.

Genetic gains in forage sorghum for adaptive traits for non - conventional area through multi-trait-based stability selection methods.

In the Asian tropics, unpredictable weather increases the risk of abiotic stresses in sorghum areas, making it harder to meet predicted demand. Genotype-by environment interaction (GEI) and the lack of an effective multi-trait-based selection approach make it challenging to breed climateresilient forage sorghum that adapts to nonconventional areas. The present investigation carried out to estimate genetic parameters, inter trait associations, genetic gain under selection (SGs) of 95 diverse forage sorghum genotypes. Fourteen forage yield and other secondary traits were evaluated at five different growing seasons at two locations. Negative and positive genetic gains under selection were estimated across different growing seasons including Kharif, Rabi and Summer in the year 2020 and 2021. The GEI effects were significant (P < 0.001) for all the studied traits. The multi trait based stability indices have been said to assist breeders in ensuring sustained progress in primary traits likeforage yield without sacrificing genetic advancement in secondary traits. Fourteen genotypes were selected through each evaluation methods including genotype - ideotype distance index (MGIDI), multi-trait stability index (MTSI), multi-trait stability and mean performance (MTMPS) and multi-trait index based on factor analysis and genotype-ideotype distance (FAIBLUP Index), assuming 15% selection intensity. According to MGIDI, the selected genotypes exhibited desired positive genetic gains for dry forage yield per plant, inter-nodal length, green forage yield per plant, and plant height and negative genetic gains for days to 50% flowering. The strength and weakness plot is a potential graphical tool as portrayed by MGIDI, to identify and develop desirable genotype for particular environment. Two genotypes, G36 (302B) and G89 (348B) were found to be common across all four evaluation methods based on all the studied traits. Multi-trait stability evaluation approaches are reliable and accessible for selecting multiple traits under varied testing environments with low multicollinearity issues. These tools proved effective in enhancing selection strategies and optimising breeding schemes for the development of climate-resilient forage sorghum genotypes. The aforementioned genotypes were found to be the most reliable, high-yielding, and earlymaturing and could be suggested for variety and hybrid development and ideotype breeding programmes to ensure the food and nutritional security.

Unravelling the novel genetic diversity and marker-trait associations of corn leaf aphid resistance in wheat using microsatellite markers.

The study was conducted to identify novel simple sequence repeat (SSR) markers associated with resistance to corn aphid (CLA), Rhopalosiphum maidis L. in 48 selected bread wheat (Triticum aestivum L.) and wild wheat (Aegilops spp. & T. dicoccoides) genotypes during two consecutive cropping seasons (2018-19 and 2019-20). A total of 51 polymorphic markers containing 143 alleles were used for the analysis. The frequency of the major allele ranged from 0.552 (Xgwm113) to 0.938 (Xcfd45, Xgwm194 and Xgwm526), with a mean of 0.731. Gene diversity ranged from 0.116 (Xgwm526) to 0.489 (Xgwm113), with a mean of 0.354. The polymorphic information content (PIC) value for the SSR markers ranged from 0.107 (Xgwm526) to 0.370 (Xgwm113) with a mean of 0.282. The results of the STRUCTURE analysis revealed the presence of four main subgroups in the populations. Analysis of molecular variance (AMOVA) showed that the between-group difference was around 37 per cent of the total variation contributed to the diversity by the whole germplasm, while 63 per cent of the variation was attributed between individuals within the group. A general linear model (GLM) was used to identify marker-trait associations, which detected a total of 23 and 27 significant new marker-trait associations (MTAs) at the p < 0.01 significance level during the 2018-19 and 2019-20 crop seasons, respectively. The findings of this study have important implications for the identification of molecular markers associated with CLA resistance. These markers can increase the accuracy and efficiency of aphid-resistant germplasm selection, ultimately facilitating the transfer of resistance traits to desirable wheat genotypes.

Analysis of β-casein gene for A1 and A2 allelic variants in Holstein-Local crossbred cattle of Bangladesh using allele-specific PCR

Beta-casein (CSN2) is one of the important bovine milk proteins synthesized by β-casein gene. The aim of this study was to investigate the A1 and A2 allelic variants of CSN2 gene in Holstein-Friesian and Local (HF×L) crossbred cattle of Bangladesh. Allele specific polymerase chain reaction (AS-PCR) was carried out for genotyping of allelic variants. A total of 390 blood samples of HF×L crossbred cattle was included from govt., military and private dairy farms. Six different crossbred genotypes were identified in the studied population as 50%HF×50%L, 62.5%HF×37.5%L, 68.75%HF×31.25%L, 75%HF×25%L, 81.25%HF×18.75%L and 87.5%HF×12.5%L. The mean frequencies of the A1A1, A1A2, and A2A2 genotypes were 0.11, 0.48, and 0.41, respectively, while the corresponding frequencies of the A1 and A2 alleles were 0.34 and 0.66, respectively. The frequency of desirable A2A2 genotype reduced from 0.60 (50%HF×50%L) to 0.38 (87.5%HF×12.5%L) with the advancement of exotic HF inheritance from 50 to 87.5%. In contrast, the frequency of A1A1 and A1A2 genotypes increased proportionately with the progression of HF inheritance level. The undesirable A1A1 genotype frequency was found highest in the HF crossbreds of private dairy farms (0.13) compared to government (0.08) and military dairy farm (0.07) that signifies the availability of upper graded cows in the private dairy farms. Altogether, this study provides current scenario of A1 and A2 allelic variants of HF×L crossbreds of Bangladesh that could be utilized to design suitable breeding plans in crossbreeding programs for production of premium quality milk.

Performance of parthenocarpic cucumber genotypes under protected cultivation for yield and horticultural traits

An investigation was conducted to identify the most desirable genotypes of parthenocarpic cucumber under protected cultivation. Experimental material consists of 23 genotypes of parthenocarpic cucumber including 1 check (KPCH-1) and the experiment was laid out in three replications with support of Randomized Block Design. ANOVA revealed significant differences among the genotypes for 17 traits. Based on the genotypes' mean performance for all traits investigated, m earliest days to first flower (26.80) and minimum inter-nodal length (7.22 cm) was observed in genotype BRPCU-1×BRPCU-8, whereas maximum number of flowers per node (2.20), number fruits per vine (31.47) and yield per vine (3.96 kg) was observed in genotype BRPCU1×BRPCU-8. The lowest node to the first flower (3.27) was observed in genotype BRPCU-2×BRPCU-7. Earliest days to first picking (39.80 days) whereas highest TSS (3.87 °Brix) and longest span of harvesting (58.67 days) was noted in genotype in BRPCU-2×BRPCU-5. The highest average fruit weight was recorded in genotype BRPCU-2×BRPCU-8 (143.07 g), while the highest fruit length was observed in genotype BRPCU-5 (20.73 cm). Genotype BRPCU-3×BRPCU-8 (3.90 cm) had maximum fruit diameter. Maximum vine length was recorded in BRPCU-6×BRPCU-7 (3.15 m). The best top-performing genotypes identified in the present study were BRPCU1×BRPCU-8, BRPCU-2×BRPCU-5, and BRPCU-3×BRPCU-8 were superior for most of the fruit yield components and quality traits.

Response of nine triticale genotypes to different salt concentrations at the germination and early seedling stages.

Salinity stress poses a major challenge to agricultural productivity worldwide, and understanding their responses at the early growth stage is vital for devising strategies to cope with this stress. Therefore, to improve triticale productivity, this study investigated the salinity stress tolerance of different salt-tolerant triticale genotypes aiming to cultivate them on saline soils. To this end, salinity stress impacts on nine triticale genotypes, i.e., Zhongsi 1084, Gannong No. 2, Gannong No. 4, Shida No. 1, C6, C16, C23, C25 and C36 at germination and early seedling stages was evaluated. Each genotype was subjected to six treatments inducing control, 40, 80, 120, 160, and 200 mM NaCl treatments to study their effect on seedling and termination traits of the nine genotypes. Compared to the overall mean seedling vigor index, the seedling vigor index was higher in the genotypes Zhongsi 1084 and C6 (39% and 18.1%, respectively) and lower in Gannong No.2 (41%). Increasing NaCl concentrations negatively affected germination and seedling traits. Compared to other genotypes, Zhongsi 1084 had the highest mean germination rate, germination vigor index, germination percentage, mean daily germination and germination energy. It also showed the lowest relative salt injury. The relative salt injury was higher in the genotype Shida No. 1 than those in Gannong No. 2, Gannong No. 4, Shida No. 1, C16, and C36 genotypes. All genotypes exhibited desirable mean germination time except for line C6. High significant positive correlations were observed among germination rate, germination vigor index, germination percentage, mean daily germination, seedling vigor index, and root length. Principal component analysis (PCA) grouped the most desirable genotypes into two clusters. Our study determined salt stress tolerance of nine triticale genotypes at germination and early seedling stages. to select salt-tolerant genotypes that can be cultivated on saline soil or after salt irrigation.

Increasing the productive potential of large and small cattle breed resources in the South of Russia based on modern breeding methods

The results of the genetic characteristics research of large and small cattle populations grown in the Southern Russia are stated. Breed-specific DNA patterns have been identified in three of the most common cattle breeds of meat productivity in arid conditions. The milk productivity of Holstein cows of different breeding lines has been studied. It was found that increasing the frequency of animals of Vis Back Ideal and Reflection Sovering lines in the parent pairs could be able to increase the level of milk productivity of offspring and improve the quality indicators of dairy raw materials. The adaptive abilities and milk productivity of imported foreign Holstein cows depending on their origin were estimated. In comparison with Australian and Danish Holstein cows, American and German analogues have a higher level of milk productivity. However Australian and Danish animals have a more flexible adaptive capacity. As a result of the comparative study of the economic and biological characteristics of two generations of Aberdeen-Angus cattle (parental foreign generation, and the first generation - obtained under breeding conditions in Southern Russia), tendencies to increase productive values are revealed. The features of the meat productivity formation in Kalmyk steers different exterior and constitutional types are investigated. It was found that the Kalmyk steers of the tall body type have a higher meat productivity compared with their analogues of medium and compact body types. However, the beef of compact steers has a higher fat percentage, more attractive taste characteristics, culinary and technological indices. The features of polymorphism of CAST, GH, GDF9, CLPG, FABP4 and MC4R genes in populations of sheep of different breeds grown in the Republic of Kalmykia, Volgograd and Rostov regions, Kabardino-Balkaria Republic were also studied. As a promising method of early diagnosis of presence economically useful traits in sheep during ontogenesis, the effectiveness of DNA analysis in young lambs and the further selection of animals with desirable genotypes according to these genes were justified.