Desirable Genotypes Research Articles

Assessment of genetic variability for yield and yield components in sesame (Sesamum indicum L.)

Sesame is an important oilseed crop of India. Assessment of genetic variability in sesame genotypes is a prerequisite for selecting desirable genotypes and traits for breeding efforts to improve yield potential. A set of 55 sesame genotypes were evaluated for 16 quantitative traits contributing for yield and components. Analysis of variance and genetic variability parameters including phenotypic coefficient of variance (PCV), genotypic coefficient of variance (GCV), heritability (h2) and genetic advance as per cent of mean (GAM) were estimated and analyzed. ANOVA showed that genotypic effects were significant for 12 out of 16 traits. High PCV and high GCV were observed for traits seed yield per plant, capsules per plant and number of secondary branches per plant. High heritability coupled with moderate to high genetic advance was observed for number of plant height, capsules per plant and seed yield per plant indicating that these traits would be valuable for improvement of seed yield and its components in sesame. The promising genotypes identified in this study could be used in sesame breeding programmes.

Assessment of genetic variability in cotton (Gossypium hirsutum L.) genotypes

The selection of high-yielding cotton lines is critical for the evaluation of phenotypic characteristics. For Cotton Breeders, it is always in preference to select desirable genotypes, based on the diversified characters from the available germplasm. The selected phenotypic diversity can be useful for aiding information in parental selection, adherence to this, a set of 12 advanced cotton lines were evaluated for genetic diversity at Cotton Research Institute, Tandojam during Kharif season in the year of 2020. The experiment was laid out in Randomized Complete Block Design (RCBD) with three replications while seven agronomical traits, were included in the experiment. The mean square of genotypes, was differed significantly (P<0.05) for all studied traits, representing that genetic diversity exists in these cotton germplasms and can be used in further utilization. Considering the agronomic performance, the genotype of B-2 was on the top in average values including plant height (174.40 cm), bolls plant-1 (42.067), seed cotton yield plant-1(139.34 g), GOT% (37.800%), and staple length (28.00 mm), hence indicating its valuable breeding resources for future cotton breeding. A Genetic Distance of 92.683 was found between B5 and B2 genotypes, which is high enough, and revealing that this pair may be used in a hybridization program for vigorous hybrid production and better selection in subsequent generations. The Variance Percentages for the first, second, and third principal components were 42.70, 23.10, and 17.20, respectively. The first three components contributed 83.00 percent of the variation for genotypes, which is high enough for the cotton crop improvements. The cotton genotypes, were divided into three categories, based on phenotypic data. The number of groups obtained, might be beneficial in generating cotton genotypes with a variety of characteristics and diversifying the Cotton Gene Pool. Keywords: cotton, genetic variations, morphological traits, seed yield.

Mangrove Habitat Assessment in Lavezares Northern Samar

Mangrove resources of the Municipality of Lavezares, Northern Samar were estimated with a total aggregate area of 1,038.4274 hectares, the 53.12% of which are distributed along the coastal margins in mainland and 46.88% along islands of the municipality. The mangal forests comprised of 13 true mangrove species belonging to seven families, which was predominantly of Rhizophoraceae combined with significant populations of Sonneratia and Avicennia species. The mangrove density varies at different sampled sites ranging from the least density of 2,100 to the densest of 24,900 stems per hectare. Six of the 12 mangrove sites have predominantly matured trees, an indicator of primary growth and six were of secondary growth with an average regenerative capacity of 72.60% of its populations.
 Bakauan bankau (Rhizophora stylosa) has the highest density of 840 trees per hectare with a relative density of 35 percent followed by Api-api (Avicennia officinales) with density of 507 trees per hectare with relative density of 21 percent. Other densities include Pagatpat (Sonneratia alba) with 453 trees per hectare and 19 percent relative density. Bakauan lalake (Rhizophora apiculata has the least density of 267 with relative density of 12 percent. 
 For purposes of determining the number of saplings/wildlings in the study area, the mangrove assessment team established 3 regenerative plots (1m x 1m) per quadrat.
 The use of acquiring data on the number of saplings in mangrove assessment is to provide information whether the area could regenerate naturally or it needs to have interventions like assisted natural regeneration or reforestation.
 Based on the findings, there were only 41 saplings/seedlings encountered in all quadrats during the assessment. It implies that the area is not capable of regenerating itself naturally. Intervention like assisted natural regeneration through enrichment planting is necessary.
 Assisted natural regeneration is the human protection and preservation of natural tree seedlings in forested areas like mangroves and improvement of the percentage of desirable species or genotypes and increasing biodiversity in a forest by interplanting.

Estimating Narrow Sense Heritability from Parent Progeny Regression and Inter-generation Correlation Coefficient Analysis for Yield and Component Characters in Segregating Lines of Urdbean [Vigna mungo (L.) Hepper

Background: Black gram or urdbean is a self-pollinated short duration diploid grain legume packed with abundant nutrients and acts as a N2 fixer, fertility restorer agent by using as mulch or catch crop. But still the crop’s value is limited due to many genetic as well as biotic and abiotic factors. Keeping this in regard, the present research was undertaken by estimating parent-progeny regression and inter-generation correlation coefficient and in turn attain narrow sense heritability values for the traits so as to determine and identify desirable and probable genotypes and their further improvement by selection in consecutive generations. Methods: The present research was aimed to ascertain the extent of narrow sense heritability through parent-progeny regression and inter-generation relationships between F2 and F3 generations for 11 quantitative traits in 14 crosses using randomised complete block design in the Experimental farm of the Department of Genetics and Plant Breeding, College of Agriculture, CSK HPKV, Palampur (H.P.) during Kharif 2018 and 2019. Result: Regression and intergeneration analysis revealed that five crosses showed positive and significant values for days to 75% maturity, thereby meaning that plants selected in the F2 population had a significant positive association with that of F3 for this trait. Estimates of narrow sense heritability were recorded highest for biological yield and days to 75% maturity. Keeping the above parameters in consideration, it was concluded that days to 75% maturity and biological yield affirm the presence of additive variance which determined as a good transmission index of genetic potentials from parent of one generation to the progeny of other, while a high regression suggests low influence of environment along with large genetic effects. So, these can be prioritized as the prime traits and used as a reliable predictor for making effective selection and improvement of genotypes for enhancing yield in subsequent generations.

Response of Fenugreek (Trigonella foenum-graecum L.) Genotypes for their Germination and early Seedling Parameters Grown Under Different Saline levels

Seedling establishment is a most critical stage that determined the crop production at later stages. An in vitro investigation was carried out at the Laboratory of the Department of Plant Breeding and Genetics, Sri Karan Narendra College of Agriculture, Jobner (Rajasthan) in Rabi season 2016-17 to study the response of fenugreek genotypes for their germination and early seedling parameters under five salt stress levels viz. 0.0 mM, 40 mM, 80 mM, 120 mM and 160 mM. Fifteen seeds of each genotype were sown in sterilized Petridish and seedling observations were recorded. Results revealed that the average value was found maximum in the control and minimum at higher salinity level for most of traits. Higher reduction was found at higher salinity levels for most of the characters viz., plumule length, radicle length, seedling length, plumule to radicle length ratio, plumule fresh weight, radicle fresh weight, plumule dry weight, radicle dry weight and seedling vigour index but germination percentage showed less reduction. The contrast between mean of various genotypes in control conditions (S0) versus Sm (mean of S1, S2, S3 and S4) for each character also showed that overall mean was highest in control as compared to the overall mean of salinity levels for all the traits. This investigation concluded that higher level of salinity (above 60 mM) adversely most affected to seed germination and other early seeding traits rather than (below 40 mM) lower salinity levels. Based upon the rank totals of genotype over different salinity levels S1, S2, S3 and S4 (Sm) and characters, the RMt-303 was found to be most desirable genotype followed by UM-385, RMt-143 and RMt-305. These lines would be used as a viable option under saline conditions and better exploit in hybridization programme.

Assessment of Genotype Stress Tolerance as an Effective Way to Sustain Wheat Production under Salinity Stress Conditions

The creation of salt-tolerant wheat genotypes can provide a basis for sustainable wheat production in areas that are particularly sensitive to the impacts of climate change on soil salinity. This study aimed to select salt-tolerant wheat genotypes that could serve as a genetic resource in breeding for salinity tolerance. A two-year experiment was established with 27 wheat genotypes, grown in salinity stress and non-stress conditions. Agronomic parameters (plant height, spike weight, number of grains per spike, thousand grain weight, and grain yield/plant) were analyzed in the phenophase of full maturity, while biochemical parameters (DPPH radical scavenging activity and total phenolic content) were tested in four phenophases. Grain yield/plant was the most sensitive parameter to salinity, with a 31.5% reduction in value. Selection based on salt tolerance indices (STI, MP, and GMP) favored the selection of the genotypes Renesansa, Harmonija, Orašanka, Bankut 1205, KG-58, and Jugoslavija. Based on YI (1.30) and stability analysis, the genotype Harmonija stands out as the most desirable genotype for cultivation in saline conditions. The presence of positive correlations between grain yield/plant and biochemical parameters, in all phenophases, enables the selection of genotypes with high antioxidant activity and high yield potential, even in the early stages of plant development.

Effect of the fatty acid marker gene diacylglycerol o-acyl transferase 1 (DGAT1) on the fatty acid composition and organoleptic properties of samples of butter produced from the milk of domestic breeds of cows

In modern conditions, effective breeding work in animal husbandry is impossible without DNA technologies. The search for selective marker genes that determine the dairy productivity of animals allows us to more reliably assess the genetic potential of breeds, adjust breeding processes, and select animals of desirable genotypes. In the Republic of Belarus, almost no work was carried out to identify genetic markers that affect the fat content, fatty acid composition of milk fat, and as a result, the yield and quality of the finished product (butter). In this regard, a special interest is the diacylglycerol O-acyltransferase 1 (DGAT1) gene, which determines the fat content. The paper presents a comparative assessment of the fatty acid composition and organoleptic properties of butter samples produced from the milk of cows of natural selection according to the gene marker of fatty milk diacylglycerol o-acyl transferase 1 (DGAT1). The results of tests of the fatty acid composition of butter from cow’s milk obtained from cows of different breeds and pedigreed its balance, compliance with the established values for volatile and unsaturated fatty acids, absence of phytosterols and adulteration of the fatty phase of the oil were emphasised. The practical significance of the conducted research lies in the use of the results obtained to carry out targeted breeding of dairy cattle according to the gene marker of fat content of diacylglycerol o-acyl transferase 1 (DGAT1) in order to increase the mass fraction of fat in milk and the yield of the finished product, as well as to improve the technology of making butter from cow’s milk and the formation of an evidence base in case of disagreement when evaluating the fatty acid composition of the product.

Genetic Variability and Association Analysis of Lisianthus (Eustoma grandiflorum (Raf) Shinn) Advanced Lines Under Mid Hill Conditions of Himachal Pradesh, India

The present investigation was designed to assess the extent of variability, genetic advance, heritability and interrelation of different traits of 19 lisianthus genotypes at ICAR-IARI Regional Station, Katrain, Kullu, HP during 2019–2021. The mean performance of different genotypes exhibited considerable range together with large value for most of the characters. The trend of variability at genotypic level was similar to that of at phenotypic for some of the characters. The path analysis clearly indicated that total number of flowers per plant was directly associated with plant height and number of shoots per plant. It is imperative that these traits should be prioritized while improving number of flowers per plant in lisianthus. The cluster analysis revealed existence of diversity among the evaluated genotypes. The first principal component analysis (PCA) score explained 33.798% of the total variation mainly associated to genotype and flower yield. The PCA biplot was effective in showing the genetic distance among the genotypes and their discrimination based on key traits of importance in lisianthus. Genotypes Ktlis-1, Ktlis-17, Ktlis-5, Ktlis-9 and Ktlis-7 were superior among the tested genotypes therefore could be exploited in lisianthus breeding to improve flower yield. Hence, the characters showing high heritability along with high genetic gain should be given due attention in the development of desirable genotypes through simple selection. Further, Genotypes from different clusters identified for specific characters may be used as parent for lisianthus breeding programme with an objective to improve the specific traits.

Characterization of fruits of eleven accessions of jackfruit

An investigation was carried out to study the characterization of eleven accessions of jackfruit at five different harvesting times. Eleven accessions were taken to study the physical characteristics and chemical characteristics. It was conducted at the BAU-GPC, Bangladesh Agricultural University, Mymensingh during the period from March to December. Physical characteristics of fruit such as weight of fruit, bulb, seed, rind and axis; skin colour, number of bulbs per fruit, nature, flavour and sweetness of bulbs and chemical characteristics such as total soluble solids, moisture, dry matter, TSS, pH, Titrable acidity, Ascorbic acid, Reducing sugar, Non reducing sugar, Total sugar contents of jackfruit bulbs were determined. Fruits were harvested at five different time, namely very early harvesting (25 May), early harvesting (4 June), mid harvesting (14 June), late harvesting (24 June) and very late harvesting (4 July). General observations on the physical characteristics of fruits such as texture, fibrousness, juiciness, flavour and sweetness of bulbs were taken at different harvesting time. Weight of fruit, weight of edible and non-edible portions also varied at five different harvesting. Total soluble solids contents were found to be the highest at early harvesting time and the lowest at late harvesting time. Early and mid-harvesting time was found to be better in all accession of jackfruit. Accession number Ah3 was found to be the best in respect of fruit, pulp and seed characteristics, which was followed by Ah1, Ah2, Ah12, Ah15, Ah18 and Ah27. A wide variation in the moisture, dry matter, TSS, pH, Titrable acidity, Ascorbic acid, Reducing sugar, Non reducing sugar, Total sugar contents was observed in the bulbs of eleven accession of jackfruit types considered in the present investigation. The results of the study are helpful for attempting crop improvement and selection of superior desirable jackfruit genotypes for bringing to cultivation.

Assessment of grain quality traits in rice under normal and water deficit condition

The main objective of this study was to assess the combining ability for rice grain quality to recognize the most desirable genotypes for rice breeding programs. A half diallel cross was made among eight rice genotypes. The obtained 28 F1 and their parents were evaluated in two separate irrigation experiments; the first experiment was irrigated every four days (normal condition). The second experiment was irrigated every ten days (a stress condition). The two experiments were designed in randomized complete block design with three replications. The results indicated that water deficit treatment significantly reduced all the studied traits except for amylose content % was increased under stressed treatments. General combining ability mean squares were highly significant for all the studied features except gelatinization temperature under drought irrigation. Specific combining ability mean squares were highly significant for grain elongation % under both conditions and amylose content % under water deficit; this indicates the importance of additive and non-additive genetic effects in the inheritance of these traits. Two crosses, Sakha106 × Sakha107 and Sakha106 × Sakha108 had the highest desirable mean values for hulling (%), milling (%), head rice, and gelatinization temperature, also lowest amylose content under both conditions. Three crosses, Giza 179 X Sakha 107, Giza 179 X Sakha 108, and Sakha 106 X Sakha 108, had the highest mean values of grain elongation % under both conditions. The cross Sakha107 × sakha108 showed highly significant positive desirable SCA effects for hulling (%) milling (%) gelatinization temperature and grain elongation. The varieties Sakha 107 and Sakha108 were the best general combiners and could be used in breeding programs for improving all the studied traits under both conditions.

Genotype-environment interaction in the production of dry matter of edgeless fodder barley (Hordeum vulgare L.)

Objective: To analyze the genotype-environment interaction (GEI) within the dry fodder production of 24 edgeless barley fodder lines (Hordeum vulgare L.) or commercial controls of the same and other species across five environments. Design/Methodology/Approach: A randomized complete block design with three repetitions was used in the five trial environments, with fodder harvested at 105 d after sowing. Data were analyzed as combined random blocks over environments and the GEI was analyzed using the AMMI model. Results: Significance (p≤ 0.01) was detected in the main effects and the GEI. Genotypes G26 (Cerro Prieto), G27 (Gabyan95), G10, G3, G19 and even genotype G24, showed interactions close to zero, so they were considered stable, while the edgeless barley lines: G6, G1 and G2 were qualified as desirable for dry fodder production, according to their superiority over the general mean and their low GEI. Study Limitations/Implications: Results may vary when evaluating other environments and genotypes. Findings/Conclusions: There are stable and desirable edgeless fodder barley genotypes that represent an option for fodder production in the study region. The oat control was considered the least productive and the locality of Zaragoza, Coahuila, is considered a potential environment for dry fodder production using edgeless fodder barleys such as those evaluated in this study, in addition to showing adequate discriminatory power.

Diagnostic accuracy of genetic markers for identification of the Lr46/Yr29 "slow rusting" locus in wheat (Triticum aestivum L.).

Wheat leaf rust, caused by fungal pathogen Puccinia triticina Erikss, annually contributes to production losses as high as 40% in susceptible varieties and remains as one of the most damaging diseases of wheat worldwide. Currently, one of the major challenges of wheat geneticists and breeders is to accumulate major genes for durability of rust resistance called "slow rusting" genes using marker-assisted selection (MAS). Until now, eight genes (Lr34/Yr18, Lr46/Yr29, Lr67/Yr46, Lr68, Lr74, Lr75, Lr77, and Lr78) conferring resistance against multiple fungal pathogens have been identified in wheat gene pool and the molecular markers were developed for them. In MAS practice, it is a common problem that cultivars exhibiting desirable marker genotypes may not necessarily have the targeted genes or alleles and vice versa, which is known as "false positives." The aim of this study was to compare the available four markers: Xwmc44, Xgwm259, Xbarc80, and csLV46G22 markers (not published yet), for the identification of the Lr46/Yr29 loci in 73 genotypes of wheat, which were reported as sources of various "slow rusting" genes, including 60 with confirmed Lr46/Yr29 gene, reported in the literature. This research revealed that csLV46G22 together with Xwmc44 is most suitable for the identification of resistance allele of the Lr46/Yr29 gene; however, there is a need to clone the Lr46/Yr29 loci to identify and verify the allelic variation of the gene and the function.

Mega-environment investigation based on the GGE biplot and genotype selection for high essential oil yield in vetiver grass (Chrysopogon zizanioides L. Roberty)

The genotype and genotype-environment interaction (GEI) significantly differed in the current study, demonstrating that genotype-environment (G × E) interaction heavily influenced genotype yield output. A combined analysis of variance revealed that the genotype and G × E interaction had a significant difference for all eleven characters. Except for the traits Ch1, Ch3, Ch4, Ch5, Ch9, and Ch11, a significant variance was found for all eleven characters over the years, indicating that the environment significantly influenced traits performance. The quality of vetiver essential oil is also affected by genotypic and environmental factors. The GGE biplot model shows that genotypes have a significant G × E interaction, split between the first and second IPCA/interaction principal component axis. In all three contexts, the genotypes V1, V13, and V14 in the center of the biplot graph were determined to be stable. The traits CH1-vs-CH3, CH1-vs-Ch7, and Ch4-vs-CH9 indicated significantly substantial genetic correlations among economic traits over the years. The traits Ch3-vs-Ch4, Ch3-vs-Ch9, Ch4-vs-Ch9, and Ch5-vs-Ch6 were highly significant and positively correlated, but Ch1-vs-Ch11 and CH7-vs-CH9 were negatively related. E1 and E2 were linked together to form one group, and E3 and E4 were linked together. GGE biplot analysis for environment interrelationships V1 and V7 was highly stable and well-performing for essential oil yield from a polygon perspective. Genotypes V1, V7, V10, V11, and V12 are stable and desirable genotypes arrayed in a concentric circle near the center of an ideal genotype. The genotypes V 17, V 41, V 69, and V 70 showed good photosynthetic efficiency. These genotypes might be suitable for large-scale farming.

Chemical composition of different accessions of jackfruit

An analysis into the chemical characteristics of eleven jackfruit accessions at harvesting time was conducted. The chemical composition of eleven accessions were explored. It was held at the Bangladesh Agricultural University's Graduate Program Center (BAU-GPC) in Mymensingh from March to December. Moisture, dry matter, TSS, pH, titrable acidity, Ascorbic acid, reducing sugar, non-reducing sugar and total sugar contents differed significantly in the bulbs of the eleven jackfruit variants investigated in this research. The findings of the study are useful for crop improvement and selecting superior desirable jackfruit genotypes for cultivation.

Genetic variability and traits association in wheat under terminal heat stress in the Haryana environment

Numbers of environmental stresses influence plant growth and development, which limits agricultural production and productivity, globally. High heat stress is a major factor that significantly reduced the wheat grain yield. Terminal heat stress adversely affects wheat plants resulting in low productivity. The ability of the plant material to mitigate the heat stress on yield may depend on the association between yield and other traits, and the variability of a trait will help identify desirable genotypes in a breeding program. For this purpose, sixty-four bread wheat genotypes were evaluated to assess genetic variability, heritability, correlations and path coefficient analysis of the traits. As result, highly significant differences in genotypes for all 15 morpho-physiological traits were observed. GCV and PCV exceeded 42% for total chlorophyll content and 16% for Main spike weight. Grain yield/plot was significantly and positively associated with spike length, spike weight, number of grains/spike, number of spikelets/spike, 1000-grain weight, biological yield/plot, GGR, total chlorophyll content and number of productive tillers/meter. As conclusion, the production of wheat in heat-stressed environment is greatly enhanced by the selection of key morphological and physiological features associated with grain yield. Five genotypes, P13833, P13828, P13031, P13723, and P13726, had high yields under heat stress condition and ought to be utilized as parents in breeding programs.

Stabilnost prinosa zrna genotipova ozime pšenice

Bread wheat is one of the most represented field crops whose level and stability of yield is very important for the food security in Republic Serbia. In the paper was investigated stability of yield expression of 15 winter bread wheat genotypes in different agroecological conditions of Serbia, using the Additive main effects and multiplicative interaction (AMMI) model and GGE-biplot method of analysis. Aim of investigation was to determine which of applied analysis is superior in identification of the most desirable genotypes for cultivation in given environments. Analysis of variance showed that genotype and genotype-environment (G×E) interaction represent highly significant sources of variability in expression of grain yield. AMMI and GGE analyses were point out similar results and an indisputable conclusion is that multienvironment trials, besides routine usage of analysis of variance, must be analized with one of this two models, which combine analysis of variance and PCA analysis. AMMI analysis is simpler for interpretation and closer to the concept of view of the agronomical trial, while GGE analysis is more complex and gives more precise interpretation of "which-won-where", i .e. for defining of narrowly adapted genotypes in given environments. Thus, G11 as the genotype with highest average yield is narrow adapted to the environment Sombor and can be recommended, as well as in the environment 2 (Kruševac), while genotypes with modest requests (G2) rather can be recommended for cultivation in the environment 1 (Kragujevac), which is characterized by less fertile soil and a smaller amount and uneven distribution of precipitation.

Screening of Indian wild apple accessions with scab and powdery mildew disease resistant gene specific molecular markers

Investigations on resistance to pathogens within local wild populations is the most efficient way for developing resistant cultivars in breeding programmes. In this study, Indian wild crab apple (Malus baccata Borkh var Himalaica) accessions maintained at two field gene banks in Himachal Pradesh were screened to find out the resistant sources. Individual trees were tested for the presence/absence of Vf, Vrl and Vbj scab resistant and Pl1 and Pl2 mildew resistant genes with eight and one SCAR markers respectively tightly linked to these genes. The potted plants were evaluated after the inoculation of pathogen. All the accessions showed diversity in relation to resistant gene to both the pathogens. All the SCAR markers K08, T06, Al07, Am19, ACS07, ACS09, Z13 and S22 were present in eight crab apple accessions. PLBJ SCAR marker linked with major genes Pl1 and Pl2 was detected in six accessions. Molecular marker assessment results almost corresponded to the data received in pot assay experiments thus were in good agreement. The study confirmed that these accessions carry scab and mildew resistant genes which could play important role in selection of desirable genotypes for apple breeding as well as use as suitable rootstock.

Variability, character association and path analysis for Annona yield and quality attributes

The knowledge of genetic variability among the genotypes for yield and quality attributes is the utmost requirement for any crop improvement work. The eighteen Annona genotypes of two species were studied for five leaves and fruit morphological attributes and twenty-nine components related to growth, yield and fruit quality. The experiment was arranged in a randomized block design in two replicates. A vast variability among the genotypes was revealed as seen based on the significant difference from ANOVA for all the quantitative traits. For morphological traits, genotypes showed variations for leaf shape, base and apex also for fruit shape and segmentation. The high magnitude of heritability and genetic advance as per cent mean was noted for most of the traits indicated presence of fixable genes and least influence of environment for inheritance. The results of the association analysis presented significant and positive association of fruit yield with growth and fruit morphology and fruit quality attributes at both genotypic and phenotypic levels. A strong influence of fruit traits and fruit quality related traits on yield observed owing to their positive and significant direct effects. The pulp/seed ratio, fruit weight, fruit per plant, total soluble solids, sugar content could be emphasize to discriminate the various Annona genotypes so as to utilize them for future hybridization programme to generate desirable genotypes for yield and quality.

Morpho-metric characterization and genetic variability studies in chrysanthemum

AbstractGermplasm characterization is essential to estimate variation and identify desirable genotypes for crop improvement. The current study was conducted on eight qualitative and 14 quantitative traits related to growth and floral attributes for characterization and grouping of 54 chrysanthemum genotypes. Wide variability was observed among most of the traits and principal component analysis revealed that the first two principal components explained most of the existing variation (>98%) in germplasm. Genotypic coefficient of variation exhibited a wide range from 9.41% (ratio of leaf length/width) to 105.99% (corolla tube length of ray florets), while phenotypic coefficient of variation varied from 10.49% (ratio of leaf length/width) to 106.38% (corolla tube length of ray florets). Broad sense heritability estimates were higher (>96%) for most of the characters, except for traits such as ratio of leaf length/width and peduncle thickness. Forty-four pair-wise inter-trait combinations showed positive genotypic and phenotypic correlations for 91 possible combinations.D2analysis revealed that genotypes of clusters I and IV to be highly distinct, and hybridization between them might have better chance to obtain desirable types.D2analysis confirmed that the cultivars in cluster IV namely, Red D Spoon, Tokyo Soldier, Yellow Reflex and hierarchical clustering showed that the cultivar Tokyo Soldier to be highly diverse. It is recommended to use the above genotypes in crossing programme for obtaining better progenies.

English

Sorghum is an important crop in Ethiopia. However, its productivity is low owing to lack of farmer-preferred and stable improved varieties. To identify suitable cultivars, multi-environment evaluation of sorghum genotypes was carried out at four locations for two years. The result of AMMI ANOVA showed that genotype (G), environment (E) and genotype-environment interaction (G×E) significantly (P<0.01) affected sorghum grain yield. The G×E term was partitioned into two significant Interaction Principal Component Axes; where they captured 65.89% of the G×E variance. Genotypes G9, G10 and G12 are highly affected by environmental changes as they had higher G×E. Genotypes G1, G7, G2, G5, G11 and G8 had relatively low G×E, indicating lower influence of the environments on their performance. The GGE analysis showed that the first two PCAs explained 75.11% of the GGE variance. Genotypes G8 and G3 were the highest-yielding genotypes and significantly out yielded the checks. Genotypes G1, G12, G7 and G8 were stable genotypes. G8 was the most desirable genotype followed by G3, G7 and G6. G8 (PGRC/E#222878 × KAT-369-1) was officially released and given a local name called Raya. This white seeded variety is preferred by farmers for various food preparations (recipes), and it commands a premium price at the market. It can give high and stable yield in the unstable environmental conditions of Northeast Ethiopia. If used in its appropriate niche, the variety can contribute to the increase of sorghum productivity, and income of the cultivators. Key words: AMMI, Desirable genotype, GGE, G×E, sorghum, stability