INDIAN JOURNAL OF GENETICS AND PLANT BREEDING

Analysis of root system architecture in rice indicates limited varietal adaptations

K. N. Gangadhara — 2024-12-26

Plant roots are the primary organs that sense and respond to soil-derived stresses. A healthy root system architecture reflects a plant’s adaptive potential. In this study, we analyzed root traits of 286 rice varieties grown in hydroponic and pot culture systems. The results revealed considerable variation and significant correlations for root traits across both systems. Cluster analysis partitioned the genotypes into two clusters, with total root length, surface area and root diameter as major determinants of variation. The results highlight marginal changes in root system traits within the indica group, resulting in distinct behaviors under pot culture conditions. However, the Aus/Boro subgroup did not exhibit similar patterns. The study underscores the importance of further investigating root system traits to achieve adaptive improvements, aiming to enhance the efficiency and effectiveness of root breeding programs. Understanding these variations can lead to the discovery of desirable traits and the development of superior rice varieties with efficient root systems.

Unravelling the genetic basis of terminal heat tolerance and yield related traits in bread wheat (Triticum aestivum L.)

Mandeep Redhu — 2024-12-26

Terminal heat stress is a critical abiotic stress in arid and semi-arid regions, causing substantial reductions in wheat productivity. Quantitative trait loci identification can aid marker-assisted selection in terminal heat tolerance wheat breeding by determining complex grain yield and its component traits. The present study reports the genetic dissection and QTL mapping for yield attributes and morpho-physiological traits using 200 recombinant inbred lines population, derived from WH711 (heat sensitive)/WH1021 (heat tolerant) grown under timely sown and late sown conditions during rabi 2018-19. Phenotyping was performed over 31 parameters, including morphological, physiological and yield attributes. Under heat stress conditions, a significant reduction was recorded in grain yield per plot and its component traits, viz. biological yield per plot, number of effective tillers per meter and gaseous parameters (photosynthetic rate, stomatal conductance and water use efficiency), whereas a reverse trend was observed in canopy temperature depression at anthesis and 15 days after anthesis stage based on total antioxidant activity and malondialdehyde content. Genetic diversity was assessed with the help of cluster analysis using 24 SSR markers data and 2-D and 3-D. PCA scaling broadly categorized the whole RIL population into two groups i.e., heat tolerant and heat susceptible. Seven novel QTLs were identified through composite interval mapping on chromosomes 1B, 3B, and 7A, associated with two key yield attributes, two morphological traits, and a physiological trait under terminal heat stress conditions. The SSR marker Xwmc 596 was found to be linked with grain yield per plot, biological yield per plot and NDVI, that can be utilized as a good source of gene deployment and enhancement of heat tolerance in future breeding.

Distinguishing rice varieties using plant image analysis by deep learning methods

Abhik Roy — 2024-12-26

Among the rice varieties developed for different purposes, Basmati varieties are unique for their morphological characters and quality. The origin, evolution and development of Basmati varieties has thrown challenges in terms of varietal classification and correct identification. Besides the classical method used in DUS testing for variety identification, new method consisting of whole plant images using deep learning algorithms was studied to identify basmati rice varieties. Classification of varieties by images of whole plant at different growth stages using deep learning algorithms was carried out to find the best algorithm and the best stage for effective discrimination of varieties. The ripening stage (terminal panicles ripened) was identified as the most suitable stage for effective classification of the varieties among the four stages namely, booting stage, 50% flowering, milk stage and ripening stage. The testing accuracy of all algorithms ranged between 60 to 73%. The testing accuracy at the ripening stage was found to be 73% using VGG 16, a deep learning model. Pusa Basmati 1609 and Pusa Basmati 1637 were identified with 100% accuracy. High testing accuracy was observed in identifying some other varieties namely, Pusa Basmati 1121, Pusa Basmati 1401, Pusa Basmati 1609, Pusa Sugandh 3. There was a high chance of misclassification among the genetically close varieties. Genetically close varieties that could not be differentiated using leaf and panicle characteristics, could be classified up to 90% accuracy using plant images and VGG 16. From this study it is concluded that plant image analysis by deep learning methods can be a viable alternative approach for identification of rice varieties.

Allelic variants of EFL3 and their association with early flowering traits in chickpea (Cicer arietinum L.)

Alok Das — 2024-12-26

Allele mining of the ELF3 gene, associated with flowering time in chickpeas, was conducted using whole genome resequencing data from 254 chickpea genotypes within the chickpea reference set, utilizing the GATK tool. A total of 671 genetic variants were identified within the ELF3 genic region, encompassing not only its genic region but also its 1 kb promoter region and intergenic regions. Among these, biallelic SNPs were predominant (641), followed by multi-allelic InDels (19), multi-allelic SNPs (9) and least of biallelic Indels (2). Out of these 641 biallelic SNPs, 44 SNPs were located across 4 exons of ELF3 gene [exon 2 (16), exon 5 (10), exon1 (9) and exon 4 (9)] while exon 3 displayed no genetic variants. Remarkably, the distinctive 11 bp deletion within the first exon of ICC96029’s Elf3 was not detected in this analysis. Instead, a missense mutation within ELF3 was identified within the studied chickpea reference set. Utilizing a candidate gene-based association mapping approach, 20 variants (comprising 18 biallelic SNPs and 2 InDels) were employed based on their presence in at least 95% of genotypes. Employing a general linear model (GLM) approach with three years of phenotypic data, a total of 4 significant marker-trait associations (MTAs) were identified. Specifically, the variants SNP_021164.1_36025048 (G/A) and SNP_021164.1_36021869 (A/C) exhibited associations with the FLD/s trait. Additionally, the SNP locus SNP_021164.1_36011429 (C/T), located within exon 5 of ELF3a, and SNP_021164.1_36013862 (C/A) located within intron 2, displayed associations with the pod_D/S trait. These allelic variants, particularly the missense mutation, carry significant importance due to their potential impact on the interaction of ELF3 with interacting proteins that eventually lead to variations in flowering time within the chickpea population.

Development of functional markers for high α-tocopherol content in Indian mustard [Brassica juncea (L.) Czern. and Coss] employing genetic and molecular analysis of VTE4 gene

Vijay Kamal Meena — 2024-12-26

Tocopherol (vitamin E) is considered an important vitamin carrying antioxidant properties. It plays a vital role in maintaining the quality and stability of oil in Brassica species. Molecular mechanisms of tocopherol content have been studied in Brassicas; however, it is untapped in Indian mustard (Brassica juncea). In the experiment, the expression profile and sequence variation of the candidate gene VTE4 controlling α-tocopherol content (ATC) were studied between two diverse parents (RLC-3 and NPJ-203) of B. juncea. The VTE4 gene expression in different tissues was almost double in NPJ-203 (high ATC genotype) as compared to RLC-3 (low ATC genotype). Moreover, sequence analysis of VTE4 in NPJ-203 and RLC-3 revealed the presence of two SNPs in the 6th exon, resulting in a shorter coding sequence (CDS) in RLC-3 (996 bp) as compared to NPJ-203 (1044 bp). Using these SNPs, an allele-specific marker was developed and validated in the F3 population. The single marker analysis revealed that the marker was significantly linked to the tocopherol content, contributing 16.46% to the total phenotypic variance. Thus, the study suggested that VTE4 is the major gene contributing to the tocopherol content, and the developed marker can be effectively used in marker-assisted breeding to improve tocopherol content in B. juncea.

Identification of heterotic maize hybrids with post flowering stalk rot resistance utilizing tropical and temperate inbred lines

Nagesh Bichewar Dattatray — 2024-12-26

Maize (Zea mays L.) is a staple cereal crop contributing to global food security. The increasing demand for maize in food and feed
industries necessitates enhancing the yield by utilizing diverse inbred lines with multiple stress tolerance. Forty inbred lines, including 30
tropical and 10 temperate lines, were crossed with two diverse testers, CML 286 and CML 451, during kharif 2021 for heterotic grouping
of post-flowering stalk rot (PFSR) resistant lines with high yield potential. The heterotic group-specific and general combining ability
(HSGCA) method classified them into three groups viz., A of CML 286 with 19 lines, B of CML 451 with 13 lines and an undetermined
group with eight lines. Six lines of group A (five tropical lines PFSR 393, PFSR 204, GP 327, PFSR 145, GP 82 and one temperate line GP
329) and five lines of group B (three tropical lines GP 36, GP 69, GP 86 and two temperate lines GP 83, GP 107) with highly significant
HSGCA effects were crossed to produce 30 single cross hybrids during Rabi 2021-22. Screening of these 11 inbred lines from both
groups A & B identified two diverse inbred lines viz., tropical GP 36 and temperate GP 83 with PSFR resistance, which can be used as
potential donors. The general combining ability (GCA) effects identified three tropical inbred lines, PFSR 145, PSFR 393, GP 36 and one
temperate inbred GP 107 line, as good general combiners for early maturity and two temperate inbred lines, GP 329 and GP 107, as
best general combiners for grain yield with moderate PFSR resistance demonstrating the potential of temperate and tropical maize
lines for increased yield and PFSR resistance. The specific combining ability (SCA) effects identified five potential hybrids GP 329 × GP
83, GP 329 × GP 86, PFSR 393 × GP 107, GP 82 × GP 83 and PFSR 145 × GP 86 with high per se performance for grain yield for future use
in maize hybrid breeding programmes with PFSR resistance.

Marker assisted improvement of stripe rust resistance in hybrid wheat

Neethu Mohan — 2024-12-26

Wheat stripe rust, caused by Puccinia striiformis Westend. f. sp. tritici Erikss. (Pst), is one of the major rust fungi that causes severe reduction in yield across the world. Gene pyramiding offers to stack resistant genes in hybrids by incorporating them into their parents. An attempt has been made to introgress the stripe rust resistance genes Yr10 and Yr15 into maintainer line 365B and restorer line 1752 R to optimize the yield potential of hybrids developing at IARI, New Delhi. B (maintainer) and R (Restorer) lines were crossed with their respective donors for Yr10 (AvocetYr10) and Yr15 (HD2967 + Yr15) genes. F1 and backcross generations were screened with linked and validated SSR markers Xpsp3000 for Yr10 in B line and Xgwm273 for Yr15 in R line. Based on marker association, plants carrying Yr10 in B line and Yr15 in R line in each backcross generation were further selected for background recovery. BC2F1 was selfed to obtain BC2F2. Marker assisted breeding helped to reduce the time and effort to improve the parental lines. These improved B lines and R lines will be used for hybrid development after doing background selections. The resistance in B and R lines will ensure the maximum harnessing of heterosis which could be declined due to disease occurrence.

Prediction of grain yield performance of commercially released finger millet (Eleusine coracana L.) varieties based on singleversus multiple-year BLUPs and YREMs

T.E. Nagaraja — 2024-12-26

Breeders effectuate trials to evaluate the performance of the germplasm lines or advanced breeding lines across multiple locations and years to recognize the promising line(s) for commercial cultivation across farmers’ fields. The majority of the theories state that cultivars’ multiple-year data from a specified location has a higher predictive ability of their future performance than single-year data. To verify this hypothesis, we predicted the cultivars’ present performance based on their previous 1- (2020), 2- (2020, 2019), 3- (2020, 2019 and 2018) and 4- (2020, 2019, 2018 and 2017) years’ grain yield performance of 77 commercially released finger millet (Eleusine coracana L.) varieties for cultivation across various cropping zones in India using (best linear unbiased predictors) BLUP and yield relative to environment maximum (YREM). The results indicated that single-year grain yield data had a reduced ability to recognize superior finger millet varieties. Further inclusion of multiple (4 and 3 years) year grain yield data seemed to predict better than singleyear grain yield data. The coefficient of determination of 5-year BLUP and YREM with maximum and minimum yearly BLUP and YREM could be used as a yardstick to accept and reject the cultivars, respectively. The varieties VL 204, RAU 8, ML365, RAU 3, VR 708 and L5 depicted high YREM and BLUP estimates with high mean grain yield and, therefore, they can be adapted to Karnataka state and can be recommended to the farmers for cultivation.

Genetic diversity and marker-trait association analysis for grain quality, yield and yield attributes in hill rice (Oryza sativa L.)

Harendra C Verma — 2024-12-26

The studies on genetic diversity and marker-trait association analysis of north-eastern hill rice for grain quality and yield attributes are of enormous importance for the identification of promising rice genotypes with better grain and cooking quality. Genetic diversity among 130 rice genotypes of North East India and marker-trait association was assessed using genotypic data of 90 SSR markers and phenotypic data. The phenotypic diversity analysis showed considerable variation across genotypes for grain quality and yield-attributing traits. Population structure analysis, distance-based neighbor joining cluster and principal coordinate analysis using genotypic data grouped the genotypes into two sub-populations. Analysis of molecular variance and pairwise FST values showed significant differentiation among all the pairs of sub-populations. Marker trait association analysis revealed a total of six associations at p < 0.0001 for grain quality and yield attributing traits with R2 ranging from 3.55 to 11.91% under the upland ecosystem. The present study validated the association of the RM240 marker with Gel consistency and plant height gene on chromosome 3. The study indicated the presence of novel QTLs for days to maturity with RM210 and RM105 and days to flowering with RM101.

Understanding the genetics of physiological traits to achieve next breakthrough in bread wheat (Triticum aestivum L.)

Shiv Kumar Singh — 2024-12-26

Optimization of different physiological processes to meet the requirement of various agronomic traits consolidation now appears to be necessary to break the fast-approaching yield ceiling. Source-sink relationship in the new high-yielding genetic base, along with better partitioning of assimilates toward developing grain, requires synergy between various developing traits at the physiological level. In the current study, eight lines with improved genetic base for the grain yield with diverse physiological traits were crossed in a diallel fashion to generate 64 crosses. The F1s were grown along with their parents to study their physiological behavior vis-a-vis combining ability. All the physiological traits are controlled by both additive and non-additive gene action with strong maternal effects. HDCSW18(P8) and HD 3226(P6) were found be good general combiners for grain yield. HDCSW18 was found to be the best general combiner for a majority of physiological traits like crop growth rate (CGR), leaf area index (LAI) and NDVI, along with grain yield. DBW 187 was found to be a good combiner for photosynthetic efficiency and may complement well with HDCSW18 for developing a highly physiologically efficient genotype. Strong deviation in expression from normal expected value in F1 combinations for grain yield was realised in cross combinations 35th ESWYT-147 (P2) X HDCSW18 (P8) for CGR, NIAW34/PHW12//43IBWSN-1187(P3) X HDCSW18(P8) for canopy temperature depression, NDVI, NIAW34/PHW12//43IBWSN-1187(P3) X HD 3226(P6) for LAI, DBW187 (P5) X HD3086(P7) for chlorophyll content, and in 35th ESWYT-147(P2), XHDCSW18 (P8) and NIAW34/PHW12//43IBWSN-1187(P3) XDBW187 (P5) for grain yield, respectively. More than 10% standard heterosis in DBW187(P5) X HDCSW18(P8), NIAW34/PHW12//43IBWSN-1187(P3) XDBW187 (P5) and HD3117 (P1) X HD2967//HD2887/HD2946//HD2733 (P4) for grain yield seems to be mainly because of highly improved leaf area index and grain weight. The high proportion of non-additive components in the genetic control of yield and harvest index offers us an opportunity either for exploitation of heterosis by developing hybrids or improvement in these traits by following a population improvement program. The presence of significant and positive standard heterosis for each of the physiological traits in at least one of the crosses offers an opportunity to develop physiologically improved fixed lines with a higher probability of higher grain yield.

Identification and quantification of resistance against Ascochyta blight complex in garden pea (Pisum sativum L.)

Sandeep Jain — 2024-12-26

One hundred elite pea genotypes were evaluated under natural as well as artificial epiphytotic conditions for three consecutive seasons to determine their relative resistance to the three predominant concurrently infecting pathogens associated with blight complex, Didymella pinodes, D. pinodella and Ascochyta pisi. Disease reaction under natural epiphytotic conditions varied with percent disease incidence and severity ranging from 38.45 to 89.45% and 11.59 to 55.14%, respectively, among test genotypes. Among the test genotypes, wide variation in the susceptibility index (Sx), area under disease progress curve (AUDPC), and relative area under disease progress curve (RAUDPC), apparent rate of infection (r), disease incidence, disease severity, percent stem girdling (%HTM) and incubation period (IP50) was recorded under artificial epiphytotic field conditions. Field trials conducted both under natural and artificial epiphytic conditions, five genotypes, namely, Eddy, PS-24, Arya Veer, CHPMR-2 and PS-19, showed consistent resistance with susceptibility index (Sx) values less than 2 and r between 0.06 to 0.08. CHPMR-2 showed a maximum incubation period of 7.46 days and a minimum percent stem girdling of 7.03%. A positive correlation between AUDPC and stem girdling, as well as disease severity, whereas AUDPC was negatively correlated with IP50, was recorded. It is the first report in Punjab that evaluated disease resistance under simultaneous stress caused by three different pathogens that cause pea blight. The identified resistant sources have the potential to provide impetus to pea disease resistance breeding.

Natural flowering patterns and key traits influencing flowering propensity in diverse sugarcane (Saccharum spp.) clones at Coimbatore

A. Anna Durai — 2024-12-26

A study was conducted to analyze the natural flowering behavior of sugarcane clones focusing on identification of the cane characteristics that influence flowering propensity. The findings revealed that clones originating from subtropical agro-climatic zones exhibited the highest flowering propensity and flowered early, whereas those from tropical zones demonstrated a lower flowering propensity and flowered later. A positive correlation was found between the days required to form visible internodes and flowering propensity. Eleven key characters studied collectively explained 40.94% of the variation, as observed in the principal component analysis. A scatter plot analysis identified 22 genotypes with high flowering potential, including diverse genotypes Co 8209, 97 R 401, CoLk 94184, CoJ 89, LG 99190 and LG 72120, which exhibited 100% flowering propensity. These genotypes can be utilized in crossing programs to enhance seedling populations for varietal selection. The study’s findings provide valuable insights into the characteristics influencing sugarcane flowering, enabling the development of more efficient breeding programs and ultimately leading to increased sugar production.

Heterogenous inbred families-derived Near Isogenic Lines for growth habit in Dolichos bean [Lablab purpureus (L.) Sweet]

Mugali Pundalik Kalpana — 2024-12-26

Identification of markers linked to loci controlling economically important traits, including growth habits, helps the selection of genotypes with desired growth habits at the seedling stage itself in crops, with no exception of the dolichos bean. Near isogenic lines (NILs) differing for a target locus are the most appropriate genetic resources for the identification of dependable genomic resources for use in a marker-assisted selection of genes controlling growth habit. In the present study, we found that 30 F2:5 progenies derived from a cross between determinate and indeterminate parents segregated for a few morphological traits, including growth habit. A total of 30 F2:5 progenies were regarded as heterogeneous inbred families (HIFs). Among these 30 F2:5 HIF, seven were segregated only for growth habits. From these seven HIFs, seven pairs of plants differing in growth habit were selected and were regarded as candidate NILs for growth habit. Of these, only six pairs were segregated for growth habit as inferred by polymorphism for alleles at SSR marker (LPD 19) linked to growth habit. Of these, only four pairs of NILs showed monomorphism (>80%) at most of the 94 background SSR markers and hence were regarded as the most putative NILs. These NILs serve as ideal genetic resources to assess the effect of growth habit genes on non-target traits in the dolichos bean.

AMP-PCR-based assay for detection and quantification of genome wide natural methylation in rice

Manikala Chandrasekhar — 2024-12-26

Natural and artificial selection efforts combined several favorable alleles of economically important traits in crop plants. However, the progress made is insufficient to meet the future food requirements. Hence, exploring new genetic resources and breeding strategies is important for sustainable improvement in production. The epigenetic variation that alters the phenotype expression without altering the gene sequence has played a crucial role in the process of evolution of modern-day crop plants. The methylation-based epigenetic variations are known to inherit more consistently than other types of epigenetic variation. However, detection and quantification of methylation in the plant genome is costly, hence limiting its utility in crop improvement. In the present investigation, we demonstrated the low-cost but effective approach for detecting and quantification of natural DNA methylation variation in the rice genome by employing custom-designed markers called amplified methylation polymorphism polymerase chain reaction markers (AMP-PCR markers). The methylation detected was scored in an effective method which was further used for quantification. The natural methylation in the diverse population of rice was used to showcase the methylation diversity.
Furthermore, the methylation in germplasm accessions, breeding lines, and released varieties indicated the significant influence of artificial selection efforts on methylation in the rice genome. The genotypes cultivated in different ecologies exhibited different types of methylations. The results ensure the utility of the AMP-PCR assay approach in the detection and utilization of methylation variation at lower costs in crop improvement programs for complex economic traits.

Phenotypic assessment of RILs of an interspecific biparental population (IR29/Oryza glaberrima Steud.) for seedling salinity tolerance and exploration QTL/haplotype in African rice (O. glaberrima S.) genome

Abhishek Mazumder — 2024-12-26

Salinity is one of the most predominant abiotic stress factors affecting crop production across the planet earth. Rice is canonically a glycophytic species that becomes sensitive to salinity stress, especially at the seedling and early reproductive growth stage. Several studies have explored the potential of African rice (Oryza glaberrima Steud.) and its interspecific progenies to be salinity tolerant at the seedling stage of growth. In this context, we tested an interspecific biparental (IR29/O. glaberrima Steud.) recombinant inbred lines (RIL) population in the present study for seedling salinity tolerance and identified a few extreme tolerant and sensitive RILs in the population and assigned (SES = 3; highly tolerant) and (SES = 9; highly sensitive) scores to the contrasting RILs in salinity stress. A few relevant parameters had been scored and a majority had shown very sharp contrast in phenotype in parents and extreme RILs. A higher ratio of stress/control phenotypic data had been observed in extreme tolerant RILs, whereas the ratio was much lower in the opposite extreme lines indicating the probable regulation of seedling salinity-related parameters by QTL region(s). Also, an assessment of the parental genotypes with Saltol QTL-specific SSR markers revealed the possibility of the existence of a novel QTL region in our African rice accession. Hence, this study opens an avenue for the discovery and mapping of novel QTL/candidate genes for seedling salinity tolerance that can be further utilized in rice breeding programs for improvement in stress tolerance in high-yielding cultivars.

Evaluation of maize (Zea mays L.) germplasm for resistance to maydis leaf blight disease

K.S. Hooda — 2024-12-26

Fungus Cochliobolus heterostrophus (Drech.) known as maydis leaf blight (MLB) or southern corn leaf blight, causes significant damage to maize crops and substantially reduces grain production. It is prevalent in warm and humid maize-growing areas throughout the world. The present study was aimed at the identification of stable sources of resistance to MLB. A set of 82 diverse inbred lines of maize were evaluated under artificial epiphytotic conditions at MLB hotspot location Delhi for two years (2020 and 2021) and in the third year at three MLB hotspot locations, namely, Delhi, Ludhiana, and Karnal during kharif 2022. The incidence of MLB was meticulously scored using a 1-9 rating scale. Based on two years’ pooled data (2020 and 2021), eight genotypes, namely, IC0620945 (DML-1278), IC0620960 (DML-1390) (Score 1.95–2.85); IC0620992 (DML-1575) (Score 0.47–2.50), IC0620997 (DML-1634), IC0621026 (DML-1828), IC0621030 (DML-1834), IC0621040 (DML-1851) and IC0612726 (DML-212-1) were resistant to MLB with score ranging from 0.47 to 3.00. These eight lines were further subjected to multi-location evaluations, Ludhiana, Karnal, and Delhi, for validation of MLB resistance. Only four lines, viz., IC0620960 (Score 1.4–2.4), IC0620992 (Score 2.0–2.5), IC0621026 (Score 1.1–2.0) and IC0621040 (2.0–2.8) could confirm resistance to MLB at all the three locations. Thus, the identified four resistant maize inbred lines may be utilized for developing promising maize hybrids with a high degree of resistance to the devastating MLB disease. Further studies can focus on understanding the genetic basis of resistance in these resistant sources and accelerate the variety development using marker-assisted breeding.

Exploration of quantitative and qualitative traits of pigeonpea [Cajanus cajan (L.) Milsp.] to understand the genetic diversity

Megha . — 2024-12-26

Pigeonpea [Cajanus cajan (L.) Milsp.] is an important leguminous crop with high protein content and nutritional value in tropical and subtropical regions. To assess the genetic diversity and correlation among qualitative and quantitative phenotypic traits in 73 pigeon pea Minicore (MC) collection of pigeon pea experiments was laid out under field and rain shelter conditions for two years. Principal component analysis contributed 85.9% of the overall variation in quantitative traits and four components contributed 76.6% in qualitative traits to total variation. Eigenvalues indicated that a pod length, seed weight and specific gravity contributed to total diversity in quantitative traits. Among the quantitative traits, the highest coefficient (CV%) was found in specific gravity (81.4%), followed by a number of primary branches (65.3%), while pod length, pod width, plant height, branch angle, seed weight and stem width showed more than 20% coefficient of variability. In cluster analysis, qualitative traits grouped the genotypes into three clusters and quantitative traits in four clusters, signifying quantitative traits offer better clustering of genotypes. The overall Shannon weaver diversity index ranged from 2.47 (seed coat color) to 0.243 (seed size). The present study indicated that MC93, MC116, MC2 displayed a higher number of seeds/pod, better pod length and pod width, whereas MC109, MC90, MC117 and MC120 showed higher seed weight. These traits seem to be an important contributor to seed yield and must be considered in the selection for high seed yield. The findings may facilitate genebank curators to understand the Mini Core (MC) collection within and among the cores, develop appropriate germplasm conservation policies, and help in crop improvement.

Identification of stable cultivars of pearl millet (Pennisetum glaucum (L.) R. Br.) based on GGE Biplot and MTSI index

Vikas Khandelwal — 2024-12-26

The present study was conducted to evaluate a total of 20 hybrids and five open-pollinated (OPVs) released varieties for their adaptability and stability and to identify traits that contributed towards yield increase under diverse ecological conditions. Variation due to location was predominantly greater, emphasizing the importance of specific adaptation. Thus, two mega environments (ME) were identified, ME1 bearing arid locations, Bikaner, Mandor and Jaipur with MPMH 17 as winning hybrid and ME2 with semi-arid locations, Gwalior, Hisar and Jamnagar with KSB and MP 7792 as winning hybrids. Hybrids with good tillering are suited for arid situations, while hybrids with higher grain and fodder yields, greater plant height, greater panicle length and late flowering are suitable for semi-arid situations. Pearson’s correlation indicated a positive and significant correlation among grain yield, dry fodder yield, panicle diameter and days to 50% flowering. The hybrids GHB 905, 86M01, HHB 197 and GHB 558 were selected through MTSI as superior hybrids for stability and performance for most of the agronomical traits across all evaluated locations. This selection index also supported 86M01 as a stable and high-mean-performing hybrid that was also widely adapted based on GGE Biplot.

Molecular cloning and in-silico characterization of gene encoding eukaryotic translation initiation factor (eIF4E) from Capsicum chinense Jacq.

Ratna Kalita — 2024-12-26

Capsicum chinense Jaqc., is well known for its high capsaicin content and medicinal properties. The productivity of this crop is extensively hindered by different viruses, among which potato virus Y (PVY) is one of the most devastating viruses worldwide. The interaction between eukaryotic translation initiation factor 4E (eIF4E) and potyvirus VPg (viral protein genome-linked) correlates with potyvirus infectivity. Cloning and characterization of the eIF4E gene related to Capsicum viral disease resistance is critical for understanding plant-pathogen interactions, especially with potato virus Y infection. The present study aims to isolate, clone, and characterize the full-length gene encoding eIF4E from C. chinense Jaqc. The full-length eIF4E gene sequence obtained was 692 bp (GenBank Accession No.: MN661348) with an ORF of 687 nucleotides and 228 amino acid residues and blast homology analysis of the CceIF4E sequence showed 99% sequence similarity with C. annum and C. baccatum. A conserved domain was identified from a CDD search. Secondary structure prediction showed 11 alpha helices and seven beta strands. Phylogenetic analysis showed a higher identity to C. annum, indicating the molecular evolution of the CceIF4E gene. The presented work will pave the way for reverse engineering for the development of viral resistance in Bhut Jolokia.

Validation of molecular markers for the identification of resistant sources against white rust disease of rapeseed mustard caused by Albugo candida

Pooja Upadhyay — 2024-12-26

White rust or white blister disease caused by oomycete fungi, [Albugo candida (Persoon) Roussal] is one of the major devastating fungal diseases of rapeseed (Brassica napus) mustard. The continuous emergence of new pathogenic races is responsible for the breaking down of the resistance in already existing resistant cultivars. So, for finding new resistant sources against the pathogen, molecular markers have become new tools. In the present study, validation of 29 simple sequence repeat (SSR) markers was done to know the presence or absence of resistance (R) genes against selected Brassica genotypes using PCR analysis. Marker trait association analysis and multiple regression analysis indicated a significant association of six markers, namely, At5g41560, Ni2BO3, BrgMS329, MB5, BRMS-017 and NI-F02a with the immune, highly resistant and moderately resistant Brassica cultivars. These molecular markers may be utilized for the identification of resistant genotypes against A. candida pathogens in rapeseed mustard.

Determining seed longevity and vigor in finger millet [Elusine coracana (L.) Gaertn.] and its genetic implication under storage

N. Kannababu — 2024-12-26

The seeds of any crop variety maintain vigor and viability to a certain period, i.e., seed longevity, also known as aging resistance and storability, which is genetically controlled and influenced by the storage environment. The study enabled the categorization of 33 cultivars of finger millet with different potentials of seed storability, seedling growth and vigor traits at different periods of natural seed aging under ambient storage conditions. The genotypic (G) differences among the cultivars for seed viability and vigor traits at eight durations of the aging period (E) were significant for all the traits. The response of genotypes to the aging period differed significantly as revealed by the genotype (G) x aging period (E) interaction. The seed germination and emergence were reduced gradually after two years of storage. The majority (88%) of cultivars maintained the standard seed germination (75%) until two years (E4) of aging. After three years (E6), 21 cultivars maintained seed viability above the standard germination (75%). Extending the aging period to three and half years (E7) further reduced to eight cultivars with >75% seed viability. At the end of the four years (E8), only four cultivars could retain seed viability to the standard (75%), i.e., G14 (86%), G26 (81%), G12 (79%) and G22 (75%) indicating seed aging resistance to maintain desired seed longevity for four years. The outcome enables the plant breeders and seed industry personnel to plan the seed storage and production programs of different seed classes in the generation system of finger millet. Further, the information also provides clues for planning the seed conservation and regeneration programs of finger millet in gene banks and active germplasm sites.

Assessment of promising sugarcane (Saccharum officinarum L.) families for enhancement of cane and sugar productivity

P. K. Mallikarjun — 2024-12-26

Sugarcane is a major source of sugar, facing constant pressure to enhance productivity due to the increased cost of cultivation and fluctuating global market prices. Assessing crosses for clonal development with enhanced productivity is hitherto a proven approach. Selecting the right parent combinations is essential for creating high-yielding progenies. In this context, 33 families (crosses) were evaluated for fluff germination, seedling survival, and productivity traits in the segregating seedling generation. Overall, across diverse crosses, out of 3,020 seedlings, 2,284 survived, with certain crosses showing better performance. A total of 482 clones were selected based on productivity and visual traits of commercial importance compared to the popular check, Co 86032 and were further assessed for cane and sugar productivity traits in the first clonal generation. High heritability was observed for most traits, indicating the effectiveness of selection. Among the clones studied, SNK 191675, SNK 190690 and SNK 191748 showed significantly higher productivity than the popular check, Co 86032. Furthermore, the present study identified promising families, namely, CoVC 14062 × CoT 8201, Thirumadhuram × CoPant 97222, Co 86032 × CoSe 92423, CoVC 14062 × Co 775, MS 68/47 (GC), Co 86011 (GC) and Co 99004 (GC), which showed superior performance in both the seedling and first clonal generations in terms of germination, seedling establishment and the percentage of selectable segregants along with productivity traits. Among these, a few crosses such as CoVC 14062 × CoT 8201, Thirumadhuram × CoPant 97222, ISH 69 (GC), CoVC 14062 (GC) and Co 85002 (GC) also exhibited an acceptable narrow range of variability with significantly superior mean productivity features over commercial popular clonal check, Co 86032. Hence, such crosses are promising not only for clonal varietal development but also for the exploitation of seedlings for direct commercial cultivation.

Unveilling heat-resilient chickpea (Cicer arietinum L.) lines under two mega chickpea growing regions in India using GGE biplot analysis

Uday Chand Jha — 2024-12-26

In the face of escalating uncertainties due to global climate change-induced heat stress, ensuring the stability of chickpea yields is
crucial for global food security. To select stable and heat stress-tolerant genotypes, 25 advanced chickpea breeding lines, including
three checks, were evaluated for various phenological, yield, and yield-related traits under diverse ecological field conditions. Under
normal sown conditions, IPC2021-71 (G13), ICC92944 (G21), and IPC2019-170 (G14) showed greater stability and desirability for yield.
Among these, IPC2021-71 outperformed in Kanpur, Punjab, and Bhopal based on the “which won where” criterion. Punjab and Bhopal
emerged as the most informative locations based on the GGE biplot “discrimination-and-representativeness” analysis. Under heat
stress conditions, stability analysis revealed that IPC2021-165 (G6), IPC2015-52 (G9), IPC2011-61 (G10), and ICC92944 (G21) were stable
performers. Additionally, the “which won where” criterion highlighted G6 as the best performer in Punjab and New Delhi under heat
stress conditions. Punjab and Delhi were identified as the most representative locations for heat stress.

Genotype x Environment interaction analysis of desi chickpea (Cicer arietinum L.) cultivars using GGE biplot model for Bundelkhand region

Hitesh Kumar — 2024-12-26

Twelve chickpea cultivars were evaluated to identify high-yielding and stable cultivars for the Bundelkhand region of Uttar Pradesh
for three consecutive years 2018-2021, at BUAT, Banda. The pooled analysis of variance indicated significant genotype, environment,
and genotype × environment interaction effect on all studied traits. Among cultivarsJG 12 was the highest yielding (3566 kg ha-1)
cultivar followed by JG 315 (3152 kg ha-1). GGE biplot analysis revealed cultivars G2 (JG 12), G4 (JG 14), G7 (JG 24), G9 (JG 322), G3 (JG
130) and G8 (JG 218) very close to the ideal genotype and have high yield along with stable performance. The identified genotype G12
was identified to be the high-yielding and well-adapted cultivar under climatic conditions of Bundelkhand and may be promoted for
commercial cultivation.

Cytological confirmation of ploidy level in a rare twin haploid of coconut (Cocos nucifera L.)

Regi J. Thomas — 2024-12-26

A rare occurrence of a haploid coconut from a twin seedling was observed in a natural population. The haploid nature of the seedling was confirmed using cytology and ploidy analysis. Amplification of tall-specific SCAR marker in the diploid seedling suggested a possible natural cross by pollen from a WCT palm. The haploids identified in the nursery may be a possible route for generating a pure line of coconut that can be used in future breeding programs.

Notification and germplasm registration

S. Gopala Krishnan — 2024-12-26

Rice
Variety Pusa 1824
Pusa 1824 (IET 28442) is a high yielding mid-early duration rice variety with seed-to-seed maturity of 120-125 days and an average yield of 95.09 q/ha across two years of testing in the state of Delhi and National Capital Territory (NCT) area. The variety recorded 31.5% yield superiority over Pusa 44, most popular non-Basmati variety grown in this region and 23.9% yield superiority over IR64 in the Delhi state trial over two consecutive years of testing. It was developed from the cross, Pusa 44/PAU 201 through pedigree breeding at the Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi. Pusa 1824 was identified for release in the NCT of Delhi by the State Seed Sub-Committee for Agricultural and Horticultural Crop, Govt. of Delhi on 28th December 2023, and subsequently released by the Central Sub Committee on Crop Standards, Notification and Release of Varieties for Agricultural Crops, Govt. of India and notified vide Gazette notification number S.O. 4388 (E) dated 8th October 2024 for commercial cultivation.