Electronic Journal of Plant Breeding

**Genetic variability and association analyses of morphological and biochemical traits in Tamarindus indica L. clones**

A. Mayavel, J. Padmanaban, A. Nicodemus, B. Nagarajan — 2025-01-06

The study aimed to investigate the genetic variability and association of morphological and biochemical characters of 60 different Tamarind clones. The experiment was conducted in 10-year-old germplasm bank of Tamarind at ICFRE-IFGTB Field Research Station, Kurumbapatti, Salem, Tamil Nadu, India. Analysis of variance revealed significant variation among clones for the morphological and biochemical characters. High phenotypic and genotypic coefficients of variation were observed for the parameters like annual yield per tree, fruit weight, pulp weight, seed weight, shell weight, vein weight, number of seeds per fruit, fruit length, fruit thickness, fruit width and total sugar content. High broad-sense heritability and high genetic advance per cent mean were recorded for annual yield per tree, tree height, number of primary branches, fruit weight, pulp weight, seed weight, shell weight, vein weight, number of seeds per fruit, fruit length, fruit thickness, fruit width, ascorbic acid, total acidity, total sugar, reducing sugar, non-reducing sugar and protein. Phenotypic path analysis highlighted positive direct effect of fruit weight, pulp weight and seed weight on annual yield per tree. Mahalanobis D-square analysis clustered the 60 tamarind clones into ten groups with higher inter-cluster distances highlighting the substantial genetic diversity present among the genetic resources. This comprehensive assessment provides insights for the genetic improvement of tamarind, aiding in the selection of superior genotypes for breeding programs.

Keywords: Genetic variability, morphological trait, biochemical traits

**Genetic assessment in early clonal population in sugarcane (Saccharum officinarum L.) for productivity traits and resistance to foliar diseases**

B. Shivarudra — 2025-01-06

The study evaluated 557 progenies from commercial/near-commercial crosses, along with eight commercial checks, for productivity traits and resistance to foliar diseases in the clonal-I generation at ARS Sankeshwar during the 2022-23 season in an augmented design. The results revealed significant variability within and between families, heritability and genetic advance for all traits. Clones such as SNK 190023, SNK 191722, SNK 190362 and SNK 191801 recorded significantly higher cane yield besides showing high resistance (HR) to foliar diseases such as brown rust, red leaf spot, eye spot, brown spot and pokkah boeng in comparison to the checks Co 09004 (early) and Co 86032 (mid-late). Families F3 (CoVC 14062 × Co 775), F5 (CoVC 14062 × CoT 8201), F8 (Thirumadhuram × CoPant 97222), F12 (CoC 671 × 85 R 186), F14 (Co 86032 × CoSe 92423), F15 (CoVC 14062 GC), and F44 (Co 99004 GC) exhibited significant superiority over the check Co 86032 for cane yield, while CoVC 14062 × CoT 8201 and Co 99004 GC showed higher selection rates and high resistance to brown rust (100%), red leaf spot (84%), and Pokkah boeng (70%) suggesting their potential for use in future breeding programs aimed at improving sugarcane productivity and disease resistance.

Keywords: Sugarcane, Flowering behavior, Progeny evaluation, Foliar diseases

**Assessment of genetic variability in oat (Avena sativa L.) germplasm using agro-morphological traits and microsatellite markers**

Parameshwaran Mathavaraj — 2025-01-06

This study assessed genetic variability among oat genotypes for twelve traits, including yield. Significant differences were found across all traits, with high heritability and genetic advance for the number of effective tillers, 1000-seed weight, and grain yield. Hierarchical clustering using morphometric traits grouped the genotypes into four distinct clusters. We identified 665 potential microsatellites using 1000 contigs from NCBI and designed possible primer pairs to develop PCR-based markers in orphan crop like oats. Validation with a panel of 31 diverse genotypes revealed that seven of ten newly developed markers detected expected alleles, with four being polymorphic. Additionally, eight reported SSRs were used to assess genotypic differences. The markers showed a mean allele richness of 2.86 (range: 2-4) and a mean polymorphism information content (PIC) of 0.37 (range: 0.15-0.96). Cluster analysis indicated three distinct clusters with a mean dissimilarity of 0.54, demonstrating the markers' effectiveness for genetic diversity assessment and breeding.

Keywords: Oats, heritability, GCV, PCV, microsatellites, molecular diversity.

**Optimizing rice (Oryza sativa L.) yield and lodging resistance using MGIDI and conventional selection indices**

Durga Prasad Mullangie — 2025-01-06

To deal with the changing climate there is a necessity to develop climate resilient varieties without compromising yield. Hence concentrating on all the traits is essential to select genotypes. On utilization of the selection indices SI 1, SI 2, SI 3, and MGIDI we have observed that the modern selection indices such as MGIDI are superior over the Smith Index as MGIDI reported a gain of 2% in yield in F₅ which simultaneously improved lodging resistance with a gain of 39.6% for section modulus and 34.7% for bending stress. In BC₁F_4, a selection gain of 5.80% for yield with simultaneous improvement in culm diameter at 5.89% gain was observed. Hence MGIDI was found to be superior over conventional indices, which improved both lodging resistance and yield.

Keywords: Smith Hazel Index, Genetic Weights, Section Modulus, Bending Stress, Multicollinearity.

**Genotypic variability for root nodulation and identification of high yielding chickpea (Cicer arietinum L.) genotypes**

Jyoti Kumari — 2025-01-06

Evaluating diverse chickpea genotypes for growth, root nodule, and yield parameters can provide valuable insights to identify genotypes with desirable traits for improved crop production. The investigation on root nodule parameters can shed light on the nodulation potential and nitrogen-fixing efficiency of the genotypes and its role in enhancing grain yield as well as soil health. Hence, the present study was carried out involving 30 diverse chickpea genotypes including 3 checks and was evaluated under natural soil condition for agronomic traits associated with high root nodulation. Under natural soil condition (Sandy loam) chickpea nodule formation and nitrogen fixation ability were observed to vary significantly. The significant differences observed among the genotypes for all the parameters indicate the presence of genotypic variability. The flowering and pod formation stages demonstrated a significantly higher number of nodules per plant compared to other stages. Regarding the distribution of root nodules, it was found that the pre-flowering stage had the highest number of nodules on the primary roots. However, as the plant progressed into the later stages of flowering and podding, the nodules shifted to the secondary roots. Several traits have been found to correlate positively and significantly with seed yield. The genotypes namely BRHT-8, Sabour chana-2, BRHT-12, JG-218, ICC-67, BRHT-1, and BRHT-6 exhibited considerably high nodulation and seed yield/hectare.

Keywords: Root nodules, Growth stages, Genotypic variability, Correlation.

**Screening and marker trait association for salinity tolerance in rice (Oryza sativa L.)**

P. Hima Bindu, G. Shiva Prasad, R. M. Sundaram — 2025-01-06

The goal of this work was to find marker-trait association to assess ability of rice genotypes to withstand salinity, which is an important consideration in abiotic stress breeding. In order to breed rice genotypes with tolerance to salinity stress, it is necessary to identify highly tolerant germplasm sources. Eighty-six rice genotypes were evaluated under field conditions. In order to determine their relationship with salinity tolerance, 16 microsatellite markers were used concurrently. Microsoft Excel's regression-based Single Marker Analysis (SMA) was used to estimate this association. Nine of the 16 polymorphic markers RM3412, RM10843, RM562, RM10793, RM 10748, RM8094, RM10694, RM1287 and RM493 showed statistically significant marker-trait relationships, suggesting the presence of important putative genetic loci linked to chromosome 1 with ability to withstand salinity. The range of 1.0% to 24.9% for the percentage of total variance of phenotype explained by the relevant markers indicates the dependability of these genetic markers for enhancing breeding for salinity tolerance. The existence of these markers in the tolerant germplasm lines from the findings of the research could be utilized to salinity tolerance cultivars through marker-assisted breeding programs because they are associated with the Saltol gene/QTL, respectively.

Keywords: Single marker analysis, Screening, Salinity tolerance, Marker trait association

**Assessment of heterosis and combining ability for fibre yield, its contributing and quality traits in Bt BGII upland cotton (Gossypium hirsutum L.)**

Smita Sunilrao Deshmukh — 2025-01-06

Heterosis breeding is one of the most practical and accomplishing tool for cotton improvement. In this context 32 intra-specific hybrids derived from eight lines and four testers were evaluated on multi-location to assess heterosis and combining ability for seed cotton yield and its contributing traits. Significant heterosis was observed in the crosses NH-2260 BGII x NH-2236 BGII, NH-2202 BGII x NH-2289 BGII and NH-2224 BGII x NH-2289 BGII for seed cotton yield and yield contributing characters over a better parent and best check. Combing ability analysis suggested the preponderance of non-additive gene action for most of studied traits. The line NH-2230 BGII and NH-2260 BGII were observed to be good general combiners for seed cotton yield and its contributing traits and the tester NH-2289 BGII was identified as the best general combiner for seed cotton yield and its contributing characters, ginning outturn, lint index. The hybrid NH-22105 BGII x NH-2236 BGII exhibited a significant positive SCA effect for seed cotton yield per plant.

Keywords: Gene action, Bt BG II, Combining ability, Heterosis, Upland cotton

**Heterosis and inbreeding depression in Aus Rice (Oryza sativa L.) for yield contributing traits**

S. G. Sarna, Ekhlaque Ahmad and A. K. M. Aminul Islam — 2025-01-06

The extent of relative heterosis (RH) and heterobeltosis (HB) of 17 F₁s and inbreeding depression (ID) in 15 F₂ generations of Aus rice were estimated for 13 yield traits. The F₁s revealed significant negative heterosis for days to panicle exertion, days to maturity, plant height, empty grains/panicle, grain breadth in P₁ × P₄, P₂ × P₁, P₂ × P₅, P₃ × P₄, P₆× P₄, P₆ × P₁₁ and P₇ × P₁₁ which indicated the possibility of superior segregants for desirable types. Significant and positive heterosis was found in the crosses P₁ × P₄, P₂ × P₁, P₂ × P₆, P₃ × P₄, P₄ × P₆ for effective tillers/plant, filled grains/panicle, 1000-seed weight and grain yield/plant. Heterosis for filled grains/panicle was significant positive in (P₃ × P₄) over mid parent and better parent. The highest significant positive RH and BH was exhibited by crosses P₈ × P₃ (34.08 and 18.65), P₂ × P₆ (23.58 and 8.53), P₆ × P₃ (16.97 and 15.27), P₃ × P₄ (11.66 and 11.10) for panicle length. Significant positive RH was observed in F₁s P₃ × P₄ (160.22) and P₄ × P₆ (63.68), and P₃ × P₄ (88.85) showed desirable HB for grain yield/plant. High degree of ID was manifested by tillers/plant, empty grains/panicle, panicle length, grain breadth and 1000-seed weight in F₁s P₆ x P₇, P₁ x P₄, P₇ x P₆, P₁ x P₄ and P₆ x P₇, respectively. Tillers/plant manifested positive and high ID in F₂ of P₆ x P₇ (42.56). The F₂ of P₇ x P₆ (-15.1) had the highest negative ID for panicle length. All crosses showed significant ID for filled grains/panicle except P3 x P4 and P6 x P7. The F₂ populations of P₆ x P₇ (14.55) showed the highest positive ID for 1000-grain weight. The highest negative ID was observed in F₂ generation of the cross P₁ × P₄ (-158.74) for seed yield per plant and the highest positive value in the F₂ generation of P₃ × P₄ (44.84). It can be concluded that hybrid breeding would be more effective for effective tillers/plant, filled grains/panicle, 1000-seed weight and grain yield/plant in rice as they exhibited relative heterosis and heterobeltiosis in desired (positive) direction. On the other hand, plant height and days to maturity revealed negative association grain yield per plant as they exhibited negative estimates of relative heterosis and heterobeltiosis.

Keywords: Aus rice, recombination, heterosis, segregation, grain yield.

**Genetic variability, heritability and genetic advance in chrysanthemum (Dendranthema grandiflora) genotypes evaluated for loose flower production**

K. Vandana, V. Vijaya Bhaskar, A. V. D. Dorajeerao — 2025-01-06

Twenty-five genotypes of chrysanthemum were evaluated for loose flower yield under open field conditions in a Completely Randomized Block Design during the year 2023-24 to ascertain their genetic variability, heritability and genetic advance for various quantitative and qualitative qualities that can be used to choose parents. Analysis of variance exhibited noteworthy variation in the genetic potential of the genotypes for every trait under study. The magnitude of phenotypic coefficient of variation (PCV) for each trait was discovered to be higher than the genotypic coefficient of variation (GCV), which demonstrated an interaction between the genotype and environment. High (>20%) PCV and GCV were noticed for all the traits evaluated in the present study. Heritability estimates ranged from a low 29.78% (stem diameter) to as high as 99.968% (flower diameter). High heritability (>60%) was noted for each of the characteristics except stem diameter. All of the growth, flowering and yield examined, estimates of high heritability combined with high genetic advance as a percentage of mean (GAM) was found, suggesting that potential significance of additive gene action among the genotypes.

Keywords: Chrysanthemum, Genetic variability (GCV, PCV), Heritability, Genetic advance (GAM)

Estimation of stress tolerance indices for identification of heat tolerant genotypes in barley

Yogender Kumar, Suman Devi, Divya Phougat and Harsh Chaurasia — 2025-01-06

The objective of present study was to assess the heat tolerance of barley genotypes employing a set of 12 heat stress indices namely SSI, TOL, STI, SSPI, YI, YSI, RSI, MP,GMP, HM, MRP and RED, estimated using grain yield. A total of 29 barley genotypes were evaluated under normal (non-stress) and heat stress conditions during 2021-22 crop season with four replications in randomized block design (RBD) at Research Area, Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar (Haryana). The genotypes, DWRB 91, BH 20-40, BH 20-05, BH 20-07 and BH 19-15 were found to be heat tolerant based on average rank of SSI for different traits. However, based on overall rank of stress indices employed on grain yield, BH 19-13, BH 20-40, BH 393, BH 19-15, BH 20-02 and BH 946 were found prominent with tolerance to heat stress. Grain yield (Y_s) showed negative association with SSI, RSI and RED and significant positive correlation with the indices viz., STI, YI, MP, GMP and HM. Hence these indices could be regarded as the best selection indicators for heat stress tolerance. PCA study considered second principal component (PC 2) as heat tolerant component based on strong correlation with STI, YI, YSI, MP, GMP, HM, MRP and Y_sunder stress condition. The genotypes of cluster I exhibited better performance under stress condition for grain yield (Y_s) and SSI, TOL, SSPI, RSI, RED, YI, YSI, and MRP. The genotypes from this group could be utilized as promising breeding material for development of new heat tolerant barley cultivars.

Keywords: Barley, correlation, cluster analysis, PCA, stress indices, heat tolerance

**Analysis of variability, heritability and trait association in four F₂ populations of Gossypium hirsutum L.**

K. Yaksha, S. Rajeswari, N. Premalatha and N. Manikanda Boopathi — 2025-01-06

Cotton is a prime crop of industrial importance. The assessment of variability provides scope for planning the breeding programmes. This study was conducted at Tamil Nadu Agricultural University, Coimbatore in F₂ generation for the crosses viz., CO 17 x KC 2, TVH 002 x KC 3, TVH002 x RAHC 1039 and TCH 1894 x NDLH 32 to estimate the variability, trait heritability and correlation among traits. In this experiment, high PCV paired with high GCV was noted for number of monopodia per plant as well as boll weight in all the four crosses. High heritability along with high genetic advance as per cent of mean were noted among all the crosses for seed index, boll weight, plant height and lint index. The plant yield of a single plant in all the crosses was noted to be significant and positively correlated with lint index, number of bolls per plant, internode length, boll weight and plant height.

Keywords: Correlation, F₂ population, Heritability, Variance

**Genetic diversity and character association studies for agro-morphological and quality traits of advanced breeding lines in field pea (Pisum sativum L.)**

Kommineni Jagadeesh, C. S. Mahto, Niraj Kumar and H. C. Lal — 2025-01-06

The present study analysed the trait associations and the genetic diversity for morphological and qualitative traits among the 23 field pea genotypes using multivariate analysis. The correlation analysis revealed that traits like primary branches per plant, pod length, seeds per pod, harvest index and biological seed yield per plant showed a note-worthy positive association at both genotypic and phenotypic levels. Path analysis revealed the correlation of pod length, harvest index and biological yield per plant was due to direct positive effects. The principal component analysis indicated that the fiseven PCs together accounted for 86.56% of the total diversity. The cluster analysis classified genotypes into five different clusters with cluster 1 comprising 18 genotypes, cluster 2 with 2 genotypes, and the remaining three mono-genotypic clusters. The selection of diverse genotypes superior in traits with positive influence on yield can result in greater genetic gains and aid in crop improvement.

Keywords: Genetic diversity, correlation, path analysis, PCA

**Inter-association and path coefficient analysis for yield and yield attributing traits in ash gourd [Benincasa hispida (Thunb) Cogn.]**

Hament Thakur and — 2025-01-06

Twenty nine genotypes of ash gourd (land races and released varieties) were evaluated during summer season (March to July) of 2022 and 2023. The main objective of the study was to evaluate the inter-associations among 15 yield and yield attributing traits, and estimate the direct and indirect effects of these traits on yield. Yield per plot (YPP) was significantly and positively correlated with number of fruits per plot (FPP), average fruit weight (AFW), equatorial diameter of fruit (ED), length of seed (LoS), width of seed (WdoS), weight of 100 seed (WoS), thickness of flesh (ToF) and equatorial diameter of cavity (EDC). The present study also revealed high positive direct effect of equatorial diameter of fruit (ED), fruit shape index (FSI), percent proportion of cavity (PPC), AFW, FPP and LoS on yield per plant. The combined results of path analysis and correlation coefficients indicated that AFW, ED, LoS, Wdos, WoS, Tof , EDC FSI and FPP are important yield attributing traits and more emphasis should be given to these traits, while going for selection of high yielding genotypes.

Keywords: Ash gourd, Genotypic, Phenotypic correlation, Path coefficient analysis

**Combining ability and heterosis for grain yield and yield component traits in maize (Zea mays L.)**

V. Shasi Kiran Reddy — 2025-01-06

The present investigation was conducted on maize hybrids to determine the extent of heterosis and combining ability for 12 quantitative traits including yield and its contributing traits during Kharif, 2021. A set of 28 F₁^sdeveloped by 8 x 8 half diallel mating design and the resultant hybrids along with parents and standard checks were evaluated in Randomised Block Design (RBD) with three replications. For standard heterosis over hybrid Bio 9544 ranged from 11.10 to 44.86 % and four F₁ cross combinations (SNL 142828-4 x CML 451, CAL 1473-4 x CML 451, CAL 1424-1 x CML 470-1 and SNL 142828-4 x CML 470-1) exhibited standard heterosis of 10 % or more for grain yield/ ha. On the basis of general combining ability (gca) estimates, V351 was the best general combiner followed by CML 451 for grain yield/ ha. Considering the per se performance, standard heterosis and specific combining ability (sca) effects, the four hybrids i.e., SNL 142828-4 x CML 451, CAL 1473-4 x CML 451, CAL 1424-1 x CML 470-1 and SNL 142828-1 x CML 470 1 were identified as promising for exploiting heterosis for grain yield.

Keywords: Maize, gca, sca, heterosis, diallel

**Genetic divergence studies in little millet (Panicum sumatrense Roth. ex. Roem. & Schult) using D² statistics and molecular markers**

Kinal Patel — 2025-01-06

Little millet is well known for abiotic stress tolerance and high nutritional value. Focused research can bring this crop into mainstream cultivation with good economic return. In kharif, 2021, fifty little millet genotypes were assessed for genetic variation and diversity for 16 quantitative traits. Variability parameters revealed considerable variation among the genotypes for all the traits studied. Phenotypic parameters being higher than genotypic ones indicated only little environmental influence which was confirmed from high heritability and genetic advance. Most of the traits were found to be expressed additively. D²technique and analysis of 14 polymorphic microsatellite markers offered different clustering pattern indicating that in the present study morphological markers could not be considered true expressers of genotypic variation, but in both the clustering pattern, most IC genotypes were confined in one cluster indicating their relatedness. Moreover, total carbohydrate content was found to be the major contributor towards genetic divergence.

Keywords: Little millet, Variance parameters, Genetic Divergence, D² Statistics, Molecular markers

Study on genetics of yield component traits under salt stress in two rice crosses raised using honeycomb selection design

C. Yoglakshmi — 2025-01-06

Yield components related to grain yield were severely affected by salinity. For the agronomically important traits, precise phenotyping of crop plants is essential under stress where soil heterogeneity is aggravated for genetic analysis and developing improved crop varieties. A set of two F₂ populations obtained from ADT(R)45 × FL478 (A × F) and ADT(R)45 × Nona Bokra (A × N) crosses along with check variety CSR10 were raised in Honeycomb Selection Design (HSD) to study the genetics of yield component traits under salt stress. The study found that the trait, panicle weight in A × F exhibited normal distribution while the other traits exhibited non-normal distribution in both the crosses. Negative skewness was observed for panicle length in both the crosses and days to flowering in the A × N indicating duplicate (additive × additive) gene interactions. Whereas positive skewness was observed for plant height, number of tillers, productive tillers and single plant yield in both the crosses, days to flowering and spikelet sterility in A × F and panicle weight in A × N indicating complementary gene interactions. Leptokurtosis was observed for days to flowering in the A × F. While the remaining characters in both the crosses exhibited platykurtosis. Transgressive segregants in both directions (towards both the parents) were obtained for all the eight characters studied in both the crosses suggesting that all traits were governed by additive gene action. Honeycomb selection design (HSD) provides an excellent phenotyping framework for studying the genetics of any quantitative traits, particularly yield and its component traits, as well as for breeding varieties that will provide more consistent results in yield in a shorter time frame.

Keywords: Skewness, kurtosis, transgressive segregation, gene action

**Genetic variability and association studies for yield and pre-harvest sprouting traits in greengram [Vigna radiata (L.) Wilczek]**

P. J. S. Pramod — 2025-01-06

The present study investigates the genetic variability and associations of agronomic traits impacting pre-harvest sprouting (PHS) in 30 greengram genotypes. Significant variability was observed across multiple traits, with seed yield per plant ranging from 2.19 to 7.82 g. Key findings indicate that hard seed percentage and alpha-amylase activity at different germination intervals are having high heritability, demonstrating genetic heritability essential for breeding strategies. High phenotypic variability suggests environmental influence on trait expression, especially in traits such as days to maturity and pod diameter. Correlation analysis revealed robust positive associations between seed yield and days to maturity, while negative correlations were noted with epicuticular wax content and pod wall thickness. The path analysis identified that days to 50 % flowering, along with alpha-amylase activity, directly affects yield, emphasizing the intricacies of trait interrelationships. This research aims to contribute towards developing PHS-resistant mung bean varieties that enhance crop yield and quality.

Keywords: Greengram, genetic variability, pre-harvest sprouting, correlation analysis, path analysis

**Analysis of genetic diversity in sesame (Sesamum indicum L.) germplasm lines based on agro-morphological traits and SSR markers**

Md Ashfaq, K. Jhansi Rani, D. Padmaja, Praduman Yadav and Usha Kiran Betha — 2025-01-06

An investigation was carried out with a set of fifty sesame genotypes to study the degree of genetic diversity based on morphological and marker based genotypic data. The genomic isolation was carried out using CTAB method and the molecular diversity was estimated with the help of fifty SSR markers using per cent polymorphism, PIC content and represented in dendogram. Morphological diversity was estimated by using D²analysis. Quantitative traits, namely plant height (67.8-147.2 cm), number of capsules per plant (36-89), number of seeds per capsule (46-70), seed yield per plant (3.20-10.89 g), oil content (40.64-50.51 %), protein content (20.5-32.42 %), oleic acid content (31.25-42.85 %) and linoleic acid content (40.39-54.11 %) showed a significant amount of variation. Fifty genotypes were grouped into fourteen clusters based on data of 15 agro-morphological traits by following Tocher′s method. SSR markers showed 36% polymorphism with an average of 2.39 alleles per locus and 0.34 PIC value indicated a trend of moderate level of genetic diversity at molecular level in the collection of genotypes. In order to assess genetic diversity and to select various lines for breeding programs, the results highlighted the importance of utilizing both agro-morphological and molecular data.

Keywords: Sesame, genetic diversity, molecular markers, D²analysis

**Genetic variability studies of diverse cashew (Anacardium occidentale L.) cultivars for growth and yield parameters in coastal zone of Karnataka**

Arati Yadawad — 2025-01-06

The present study aimed to evaluate the performance of cashew cultivars developed/collected from different cashew growing regions of the country. The experiment was conducted at Agricultural and Horticultural Research Station, Ullal, belonging to coastal zone of Karnataka during 2023-24. Fifteen year old standing cashew orchard planted with 42 diverse cashew cultivars were evaluated for 15 fruit, nut, growth and yield parameters following randomized complete block design with two replications. Highly significant variations of GCV and PCV coupled with high heritability and GAM was observed for most of the traits indicating the predominance of additive gene action and possibilities of achieving high genetic gain from selection. Character association studies revealed the importance of yield component traits like nuts per panicle, canopy surface area and canopy spread (E-W and E-W) that forms the basis for selection of promising cultivars for yield improvement in cashew. Potential high yielding varieties like Ullal 1, Bapatla 8, Gubbi 3/111, NRCC Selection 2, Ullal 3 and VRI-3 were found to be suitable in coastal zone of Karnataka. Bapatla 8, Priyanka and Vengurla 7 cultivars exhibited superiority for both nut weight and nut yield per tree. This study provides useful information on genetic control of important yield traits and choice of potential cultivars in hybridization program to explore the variability and hybrid vigor for improvement of productivity and quality in cashew.

Keywords: Cashew, coastal zone, nut yield, variability, correlation

Principal component analysis (PCA) as a genetic diversity tool to understand the variation of rice mutant culture

S. Palaniyappan, P. Arunachalam, S. Banumathy and S. Muthuramu — 2025-01-06

The current research experiment was carried out to analyze the genetic variations among rice mutants and homozygous lines from cross derivatives by principal component analysis (PCA). The PCA results had shown the first five PCs accounted 83.20 per cent of total genetic variation. The thirty six rice genotypes were formed into four groups. Among the variables studied, hundred grain weight (0.907), grain length (0.837), grain width (0.799) and plant height on 50^th day (0.617) positively contributed to 29.15 % variation of first PC. Whereas, days to maturity (0.708), days to fifty percent flowering (0.643) and flag leaf breadth (0.609) contributed mostly for 21.60 percent variation of second PC. More precisely, the grouping revealed that the EMS mutants of Anna (R) 4 were potentially mutated not only for the grain type and also for yield related traits such as flag leaf length and breadth, panicle length, plant height. The genotypes grouped 1 and 4 had potential to select higher grain yield with improved grain quality suitable for rainfed condition.

Keyword: Rice, mutants, PCA, variation.

Genetic diversity studies for yield and physiological traits using principal component analysis in little millet

T. Venkata Ratnam and L. Madhavi Latha — 2025-01-06

Principal Component Analysis (PCA) was conducted to assess the genetic variability among 50 little millet genotypes based on yield and physiological traits. Results revealed six principal components with an Eigen value more than one, which accounted for 74.25% of the total variability. PC 1 contributed the most towards the total variability at 27.98%, while PC 2, PC 3, PC 4, PC 5, and PC 6 contributed 12.90%, 11.19%, 8.93%, 7.08%, and 6.14% respectively. Days to 50 per cent flowering, grain yield plot^-1, harvest index, leaf area index at both panicle and 15 days after panicle initiation, specific leaf weight at 15 days after panicle initiation, and main panicle weight were the foremost contributors to genetic diversity among the studied genotypes. The biplot diagram revealed that WV-167, BL-6, TNPsu-174 and GPUL-2 were the most diverse genotypes, with high yield potential compared to other entries. GPUL-1 and DLM-186 are likely to be drought resistance due to lower relative membrane injury (%). Hybridization among these genotypes could result in transgressive segregants with desirable traits for yield and physiological characteristics.

Keywords: Little millet, Principal Component Analysis, Physiological traits, Yield traits

Electronic Journal of Plant Breeding

Genetic variability and association analyses of morphological and biochemical traits in Tamarindus indica L. clones

Genetic assessment in early clonal population in sugarcane (Saccharum officinarum L.) for productivity traits and resistance to foliar diseases

Assessment of genetic variability in oat (Avena sativa L.) germplasm using agro-morphological traits and microsatellite markers

Optimizing rice (Oryza sativa L.) yield and lodging resistance using MGIDI and conventional selection indices

Genotypic variability for root nodulation and identification of high yielding chickpea (Cicer arietinum L.) genotypes

Screening and marker trait association for salinity tolerance in rice (Oryza sativa L.)

Assessment of heterosis and combining ability for fibre yield, its contributing and quality traits in Bt BGII upland cotton (Gossypium hirsutum L.)

Heterosis and inbreeding depression in Aus Rice (Oryza sativa L.) for yield contributing traits

Genetic variability, heritability and genetic advance in chrysanthemum (Dendranthema grandiflora) genotypes evaluated for loose flower production