Indian Accessions Research Articles

Analysis of genetic divergence and heterogeneity in vetiver (Chrysopogon zizanioides (L.) Roberty) using SCoT and ISSR molecular markers

The present study aimed to evaluate the genetic diversity among vetiver accessions obtained from diverse geographic locations worldwide using two molecular markers, namely Inter-Simple Sequences Repeat (ISSR) and Start Codon Targeted Polymorphism (SCoT). The objective of this analysis was to enhance the taxonomic accuracy and to ascertain the evolutionary relationships among the studied accessions. The study population comprised three groups, i.e., North Indian, South Indian, and Abroad Population. The effective multiplex ratio (EMR), marker index (MI), resolving power (Rp), and polymorphic information content (PIC) were determined. The SCoT system exhibited higher values for all parameters examined except for resolving power (Rp), which was lower than ISSR. The Mantel test showed a weak correlation between ISSR and SCoT, indicating that these marker systems have limited genetic background similarities in vetiver. Analysis of molecular variance (AMOVA) shows a significant differentiation among the investigated populations, with the majority of the variation observed within the populations. The South Indian accessions were the most heterogenic to others. The fixation index and population analysis indicate a close relatedness among the accessions. This study used SCoT-based molecular markers as a novel approach to evaluate the genetic diversity and relationships among different vetiver accessions. These studies will assist in the molecular ecology, genetic mapping, and identification of elite varieties and the efficiency of the breeding methodology in fulfilling worldwide industrial demand.

Genetic diversity and structure of Tunisian and Indian date palm (Phoenix dactylifera and sylvestris) cultivars and genotypes revealed by AFLP markers

The date palm breeding programs need to discover valid genetic fingerprints to characterize cultivars and assess their genetic diversity. This study assessed the genetic diversity among thirty-nine date palm cultivars from Tunisia (Phoenix dactylifera) and India (Phoenix sylvestris) by using six AFLP (Amplified Fragment Length Polymorphism) markers. 360 loci were amplified, with 127 loci polymorphic (34.35 %). The Jaccard's similarity coefficient ranged from 0.161 to 0.931, with the mean genetic distances of 0.568. AFLP's average marker index value was 7.28, with a resolving power of 10.91. The analysis of population structure showed two main clusters with a clear separation between Tunisian and Indian cultivars.Furthermore, the heatmap analysis allowed the identification of 10 bands specific to the Indian accessions, which were not detected in Tunisian genotypes. These loci could be linked to genes involved in adapting the species in Indian lands, which allowed the study of the genetic diversity of date palm resources of different origins, confirming the existence of at least two origins of domestication. Additionally, identifying AFLP loci specific to P. dactylifera and P. sylvestris will significantly contribute to breeding programs by exploiting species-specific polymorphisms.

Evaluating the genetic variability in selected accessions of medicinal legume Mucuna pruriens (L) DC through ISSR markers

Mucuna pruriens, a widely available but underutilized legume in India, stands out for its nutritional and medicinal potential. Understanding the genetic diversity of M. pruriens is vital for its conservation and utilization in breeding programs aimed at enhancing its nutritional and agronomic traits. In this regard, molecular markers like ISSRs offer a reliable and informative tool for assessing genetic diversity. In the present study, 23 M. pruriens accessions from northeastern India were evaluated using ISSR markers, revealing high levels of polymorphism and significant genetic diversity. A total of 512 amplicons were generated across 33 ISSR primers, with an average polymorphic percentage of 98.05 %. PIC values ranged from 0.22 to 0.50, indicating substantial genetic variation within the accessions. Supplementary indicators such as EMR and MI were employed to evaluate the marker system's efficacy. EMR ranged from 6 to 22, averaging 14.95, while MI ranged from 2.64 to 9.02, averaging 6.04, with a positive correlation observed between EMR and MI. Cluster analysis based on Jaccard's similarity coefficient classified the accessions into two major groups, with the northeastern Indian accessions displaying higher diversity compared to those from other regions of India. Interestingly, geographical proximity did not consistently correlate with genetic similarity, suggesting complex patterns of gene flow and historical germplasm exchange. Overall, this study provides valuable insights into the genetic diversity of M. pruriens and highlights the importance of conserving and utilizing this underutilized legume for addressing global food security challenges.

Physical characterization of cumin (Cuminum cyminum L.) schizocarps of different origins cultivated in Morocco

An initial investigation on the physical traits of the cumin (Cuminum cyminum L.) schizocarps was examined in order to select the best genotypes of cumin grown in three regions of Morocco (Drâa-Tafilalet, Marrackech-Safi, and Oriental). This operation was conducted on 34 cumin accessions from six origins (local, India, Syria, Egypt, Turkey, and Saudi Arabia). To evaluate differences between the physical properties among accessions, length, width, thickness, and both the volumetric mass and the thousand-schizocarp mass were measured. Geometric properties (geometric mean diameter, sphericity index, specific mass and surface area) and gravitational parameters (bulk density, true density, and porosity) were calculated for each accession. Heritability (broad sense), phenotypic and genetic variabilities are also assessed. The average values of the evaluated parameters were found to be significantly different (p < 0.01) between accessions. The physical characteristics of schizocarps were significantly influenced by their origin, cultivated provinces and irrigation methods. Length, width, thickness and length of style range on average from 5.7 to 6.8 mm, 1.5 to 2.5 mm, 1.2 to 1.8 mm and 0.6 to 0.9 mm, respectively. Local and Egyptian accessions were the best-sized accessions. Regarding the weight, the Indian accession C11 registered the best volumetric mass 52.9 g, while the thousand-mass was found to be higher in the local accession from Zagora C19 with 7.3 g. The results showed that the phenotypic coefficient of variation (PCV) was higher than the genotypic coefficient of variation (GCV). The highest PCV and GCV were length of style (30.0%) and true density (24.4%), respectively. Volumetric mass had the highest value of heritability (99%). PCA analysis of seed origin showed clearly the ordination of cumin schizocarps into three groups. The big-sized schizocarps group is composed of local and Egyptian accessions, while the Saudi Arabia accession was individualized in a single group. Regarding the cultivated zone in Morocco, the ordination of schizocarps according to the province revealed four distinct groups. Finally, this study showed that irrigation mode may also affect the physical properties of cumin schizocarps.

The ricebean genome provides insight into Vigna genome evolution and facilitates genetic enhancement.

The ricebean genome provides insight into Vigna genome evolution and facilitates genetic enhancement.

Ultrasonic-assisted extraction of fenugreek flavonoids and its geographical-based comparative evaluation using green UHPLC-DAD analysis

BackgroundThis study, for the first time, reports a simultaneous determination of flavonoids; rutin (RT), quercetin (QT), luteolin (LT), and kaempferol (KF) in different origins of fenugreek seeds samples (N = 45) using a green UHPLC-DAD analysis MethodologyUltrasound-assisted extraction (UAE) was employed to extract fenugreek flavonoids using different polarity solvents of n-hexane (n-hex), dichloromethane (DCM), and methanol (MeOH) ResultsThe extract yield on an individual basis was observed in the range of 1.03–17.29 mg, with the highest yield (mg/sample) for the Egyptian sample (17.29 mg). The highest total extract yield (mg/origin) was observed for the Iranian sample (82.28 ± 5.38). The solvent with the highest extract yield (mg) was n-hex 169.35 ± 13.47, followed by MeOH 114.39 ± 12.27. The validated green UHPLC-DAD method resulted in a short runtime (9 min) with an accuracy of 97.86(±12.32)-101.37(±5.91), r2-values = 0.993–0.999, LOD = 2.09–4.48 ppm, and LOQ = 6.33–13.57 ppm for flavonoids analysis within the linearity range of 1–500 ppm. The general yield for flavonoids exhibited a descending order (ppm): RT (2924.55 ± 143.84) > QT (457.05 ± 34.07) > LT (82.37 ± 3.27) > KF (4.54 ± 0.00). The yield (ppm) for the flavonoids was more in MeOH solvent (3424.81 ± 235.44) constructing a descending order of MeOH > n-hex > DCM. For an individual flavonoid yield; MeOH was seen with an order of RT > QT > LT, n-hex (LT > QT), and DCM (RT > LT > QT). The statistical analysis of PCA (principle component analysis) revealed a widespread distribution of flavonoids in fenugreek seeds with a variance of 35.93% (PC1). Moreover, flavonoids extraction was prone to the nature and specificity of the solvent used (PC2: 33.34%) rather than the amount of the extract yield (P = 0.00). The K-mean cluster analysis showed the origins with higher flavonoids yield in appropriate solvent as I3M (Indian accession # 3 MeOH extract) with more QT amount, IR2M (Iranian accession # 2 MeOH extract) with more LT amount along with I2M (Indian accession # 2 MeOH extract) and Q2M (Qassim Saudi Arabia accession # 2 MeOH extract) containing high amount of RT. The outcomes are supported by KMO (Kaiser-Meyer-Olkin) and Bartlett’s test value of 0.56 with X2-value of 191.87 (P = 0.00) ConclusionThe samples were effectively evaluated and standardized in terms of flavonoid amount suggesting a significant variation in fenugreek quality.

Development and Evaluation of a New Source of Tolerance to Fusarium Wilt Race 1.2 in Melon

Melon Fusarium wilt, caused by Fusarium oxysporum f. sp. melonis (Fom), is one of the most prevalent fungal diseases affecting melon (Cucumis melo L.). We aimed at finding an effective resource for breeding cultivars tolerant to Fom race 1.2, which includes pathotypes that cause yellowing (race 1.2y) and wilting (race 1.2w). We screened 294 melon accessions that originated mainly in Africa and Asia for tolerance to race 1.2y. The highest level of tolerance was observed in the Indian accession PI124550; one of the five PI124550 plants tested showed no disease symptoms. From this plant, a tolerant inbred line, YR01, was developed after seven rounds of selfing combined with selection for tolerance to race 1.2y. YR01 had a high level of tolerance not only to race 1.2y, but also to race 1.2w. It was more tolerant to race 1.2y than the tolerant reference control ‘Isabelle’ and was equally tolerant to race 1.2w. Analysis of F1 hybrids and an F2 population developed by crossing YR01 with susceptible ‘Earl’s Favorite Harukei 3’ suggested that YR01 had multiple recessive and dominant (or codominant) genes for tolerance to race 1.2y and one dominant gene for tolerance to race 1.2w. These results indicate that PI124550 and its derivative YR01 are a promising breeding material with novel genes conferring practically useful tolerance to both pathotypes of race 1.2.

Gene fusions, micro-exons and splice variants define stress signaling by AP2/ERF and WRKY transcription factors in the sesame pan-genome.

Evolutionary dynamics of AP2/ERF and WRKY genes, the major components of defense response were studied extensively in the sesame pan-genome. Massive variation was observed for gene copy numbers, genome location, domain structure, exon-intron structure and protein parameters. In the pan-genome, 63% of AP2/ERF members were devoid of introns whereas >99% of WRKY genes contained multiple introns. AP2 subfamily was found to be micro-exon rich with the adjoining intronic sequences sharing sequence similarity to many stress-responsive and fatty acid metabolism genes. WRKY family included extensive multi-domain gene fusions where the additional domains significantly enhanced gene and exonic sizes as well as gene copy numbers. The fusion genes were found to have roles in acquired immunity, stress response, cell and membrane integrity as well as ROS signaling. The individual genomes shared extensive synteny and collinearity although ecological adaptation was evident among the Chinese and Indian accessions. Significant positive selection effects were noticed for both micro-exon and multi-domain genes. Splice variants with changes in acceptor, donor and branch sites were common and 6-7 splice variants were detected per gene. The study ascertained vital roles of lipid metabolism and chlorophyll biosynthesis in the defense response and stress signaling pathways. 60% of the studied genes localized in the nucleus while 20% preferred chloroplast. Unique cis-element distribution was noticed in the upstream promoter region with MYB and STRE in WRKY genes while MYC was present in the AP2/ERF genes. Intron-less genes exhibited great diversity in the promoter sequences wherein the predominance of dosage effect indicated variable gene expression levels. Mimicking the NBS-LRR genes, a chloroplast localized WRKY gene, Swetha_24868, with additional domains of chorismate mutase, cAMP and voltage-dependent potassium channel was found to act as a master regulator of defense signaling, triggering immunity and reducing ROS levels.

Revised molecular phylogeny, global biogeography, and diversification of palms subfamily Coryphoideae (Arecaceae) based on low copy nuclear and plastid regions.

Coryphoideae are palmate-leaved palms from the family Arecaceae consisting of 46 genera representing 421 species. Although several phylogenetic analyses based on different genomic regions have been carried out on Coryphoideae, a fully resolved molecular phylogenetic tree has not been reported yet. To achieve this, we applied two phylogenetic reconstruction methods: Maximum Likelihood and Bayesian Inference, using amplified sampling by retrieving chloroplast and nuclear DNA sequences from NCBI and adding newly produced sequences from Indian accession into the dataset. The same dataset (chloroplast + nuclear DNA sequences) was used to estimate divergence times and the evolutionary history of Coryphoideae with a Bayesian uncorrelated, lognormal relaxed-clock approach and a Statistical Divergence-Vicariance Analysis method,respectively. The phylogenetic analyses based on a combined chloroplast and nuclear DNA sequence dataset showed well-resolved relationships within the subfamily. Both phylogenetic trees divide Coryphoideae into two main groups: CSPT (Crysophileae, Sabaleae, Phoeniceae, and Trachycarpeae) and the Syncarpous group. These main groups are segregated into eight tribes (Trachycarpeae, Phoeniceae, Sabaleae, Crysophileae, Borasseae, Corypheae, Caryoteae, and Chuniophoeniceae) and four subtribes (Rhapidine, Livistoninae, Hyphaeninae, and Lataniinae) with strong support-values. Most previously unresolved and doubtful relationships within tribes Trachycarpeae and Crysophilieae are now resolved and well-supported. The reconstructed phylogenetic trees support all previous systematic revisions of the subfamily. All Indian sampled species of Arenga, Bentinckia, Hyphaene, and Trachycarpus show close relation with their respective congeneric species. Molecular dating results and integration of biogeography suggest that Coryphoideae originated in Laurasia at ~95.12Ma and then diverged into the tropical and subtropical regions of the whole world. This study offers the correct combination of nuclear and plastid regions to test the current and future systematic revisions.

Comparative analysis of physico-chemical properties and fatty acid composition of linseed (Linum usitatissimum L.) oils of Indian accessions

Comparative analysis of physico-chemical properties and fatty acid composition of linseed (Linum usitatissimum L.) oils of Indian accessions

Characterization of Some Cultivated Rice (Oryza sativa L.) Based on Phenotypic, Physicochemical and Cooking Properties

Evaluation of rice genetic diversity is an important step for character specific varietal development program. The present study characterizes 15 rice germplasm of Indian accessions on the basis of agro morphological, physicochemical and cooking parameters. The cultivars showed high degree of variations on their traits. Mean plant height of 88.96 cm, flag leaf length (26.48 cm), flag leaf width (1.17 cm), grain per panicle ( 130), panicle length (20.97 cm), days to 50% flowering (112.06 days), kernel length breadth ratio (2.65), cooked kernel length breadth ratio (3.25), linear elongation ratio (1.65). Out of 15 rice cultivars, only Sada nunia and Das nunia are aromatic rice and Sada nunia also contain awn. Plant height showed significant positive correlation with PnL and DF and significant negative correlation with GB. GL positively significantly correlates with FLL, GrWt with GL and GB, DF with MT. The cluster analysis grouped the 15 cultivars into 4 clusters with 37.5 dissimilarity coefficient. The high variability with promising traits among the cultivars expected to be significance for future rice breeding programmes.

A molecular clue towards fusarium wilt resistant gene in melon (Cucumis melo L.) germplasm

Fusarium wilt [Fusarium oxysporum f. sp. melonis (Fom)],is one of the most serious diseases of muskmelon in India.Fifty accessions of muskmelon and its relatives collectedfrom diverse sources were subjected to molecular screeningwith Fom1 and Fom2 gene specific markers. Presence ofFom1 (R) gene was confirmed using RG-9-2 marker where assusceptible allele was confirmed with another set of primerS-TAG/GCC-470. Out of 50 germplasm lines, 16 lines werefound to be positive. Among which, eight were homozygousand eight were heterozygous in nature. The S-TAG/GCC-470 could only able to confirm susceptible allele in exoticlines but was failed to confirm the same in Indian accessions.While for Fom2 gene, a combination of R-408 (R allele) andS-342 (S allele) were used. Six genotypes containedhomozygous resistant gene while only three lines showedheterozygous nature for Fom2 gene. Only two genotypesviz., SM-2012-12 and IC-267359 contained both the resistantgenes, whereas Kajri Sel.1, IC-267375, MM-314 and MM-4305 contained Fom1 gene. These results conclude thepresence of novel resistant gene in Indian melon gene pooland there is an opportunity for developing new gene basedmarkers for these novel genes which will be useful tostrengthen the resistance against newly evolving pathogenicraces.

Genetic characterization of global collection of flax (L. Usitatissimum L.) utilizing molecular marker

In assess the sufficient knowledge of genetic diversity, population structure and linkage disequilibrium were estimated among the three representative sub-population: Pop 1 (Indian accessions), Pop 2 (different species of Linum genus) and Pop 3 (exotic accessions) of flax using ISSR marker systems. A total of 118 number of alleles were amplified by eleven primers, with an average of 10.64 alleles per primer (100 bp −2072 bp). The maximum PIC value (0.25) was observed in the primer combination UBC808, which indicated that it as the most informative primer among the eleven primers to study genetic diversity among flax genotypes. The results of the AMOVA indicated that genetic variation within sub-populations (92%) was significantly higher than the variation among the sub-population (8%). According to the results of split network tree analysis, population structure and PCA, the total 264 flax accessions were distinctly clustered into eight genetic groups. Overall the mean LD value was less than the threshold level (r2 < 0.1) explaining that the population has a high level of outcrossing or gene flow. The knowledge generated through ISSR fingerprinting in this study has enhanced our conception of population structure and LD of the flax population, which has high implications for genetic improvement and association mapping.

Resistant Sources and Genetic Control of Resistance to ToLCNDV in Cucumber.

Tomato leaf curl New Delhi virus (ToLCNDV) is a severe threat for cucurbit production worldwide. Resistance has been reported in several crops, but at present, there are no described accessions with resistance to ToLCNDV in cucumber (Cucumis sativus). C. sativus var. sativus accessions were mechanically inoculated with ToLCNDV and screened for resistance, by scoring symptom severity, tissue printing, and PCR (conventional and quantitative). Severe symptoms and high load of viral DNA were found in plants of a nuclear collection of Spanish landraces and in accessions of C. sativus from different geographical origins. Three Indian accessions (CGN23089, CGN23423, and CGN23633) were highly resistant to the mechanical inoculation, as well as all plants of their progenies obtained by selfing. To study the inheritance of the resistance to ToLCNDV, plants of the CGN23089 accession were crossed with the susceptible accession BGV011742, and F1 hybrids were used to construct segregating populations (F2 and backcrosses), which were mechanically inoculated and evaluated for symptom development and viral load by qPCR. The analysis of the genetic control fit with a recessive monogenic inheritance model, and after genotyping with SNPs distributed along the C. sativus genome, a QTL associated with ToLCNDV resistance was identified in chromosome 2 of cucumber.

Epigenetic Variability Among Saffron Crocus (Crocus sativus L.) Accessions Characterized by Different Phenotypes.

This work represents the first epigenomic study carried out on saffron crocus. Five accessions of saffron, showing differences in tepal pigmentation, yield of saffron and flowering time, were analyzed at the epigenetic level by applying a methylation-sensitive restriction enzyme-sequencing (MRE-seq) approach. Five accession-specific hypomethylomes plus a reference hypomethylome, generated by combining the sequence data from the single accessions, were obtained. Assembled sequences were annotated against existing online databases. In the absence of the Crocus genome, the rice genome was mainly used as the reference as it is the best annotated genome among monocot plants. Comparison of the hypomethylomes revealed many differentially methylated regions, confirming the high epigenetic variability present among saffron accessions, including sequences encoding for proteins that could be good candidates to explain the accessions’ alternative phenotypes. In particular, transcription factors involved in flowering process (MADS-box and TFL) and for the production of pigments (MYB) were detected. Finally, by comparing the generated sequences of the different accessions, a high number of SNPs, likely having arisen as a consequence of the prolonged vegetative propagation, were detected, demonstrating surprisingly high genetic variability. Gene ontology (GO) was performed to map and visualize sequence polymorphisms located within the GOs and to compare their distributions among different accessions. As well as suggesting the possible existence of alternative phenotypes with a genetic basis, a clear difference in polymorphic GO is present among accessions based on their geographic origin, supporting a possible signature of selection in the Indian accession with respect to the Spanish ones.

Characterization of Agro-morphological Traits of Tartary Buckwheat Germplasm Under Spring Cultivation and Analysis of Health-Related Primary Bioactive Components in Seeds by HPLC Method

The primary bioactive components of buckwheat seeds, rutin, and quercetin, have health-related benefits such as anti-inflammatory, antioxidant, anti-diabetic, and anti-cancerous. In the current study, we characterized the agro-morphological traits of diverse tartary buckwheat germplasm accessions under the spring cultivation and estimated the major flavonoid contents of seeds. The content of rutin and quercetin ranged from 4354.1 to 17,196.01 and 8.9 to 611.7 µg g−1 DW, respectively. The highest content of rutin was found in ‘C9714’ collected from China. The highest and lowest content of quercetin was found in Indian accessions ‘I8345’ and ‘I8622’, respectively. Moreover, we found that accessions with dark-brown seed coat color had a significantly higher mean rutin content than that of accessions with other seed coat color. In the principal component analysis, the first three components (PC1, PC2, and PC3) accounted for 77.14% of the total variation. The number of nodes and branches, number of days to flower, and maturity were the main contributors of variability to PC1. The 1000-seed weight was the main contributor of variability to PC2; whereas, the rutin and quercetin were the main contributors of variation to PC3. We identified nine accessions with the rutin content above 10,000 µg g−1 DW and three accessions with quercetin content above 40 µg g−1 DW. The selected accessions could be used as a nutritional source of health-related bioactive metabolites.

Understanding genetic diversity, population structure and development of a core collection of Indian accessions of watermelon (Citrullus lanatus(Thunb.) Matsum. and Nakai)

AbstractMost of the modern-day improved watermelon varieties succumb to various biotic and abiotic stresses mainly because of their narrow genetic base. Insights into the genetic diversity and population structure are crucial for broadening the genetic base and improving the adaptive value. The present experiment was conducted to study the genetic diversity and population structure of a germplasm panel comprising 336Citrullussp. accessions. Another objective was to formulate a core collection of IndianCitrullussp. accessions. Data from 23 highly polymorphic microsatellite markers were used for genetic diversity and population structure analysis while both molecular and phenotypic data from 17 traits were used to formulate the core set. The markers yielded a total of 69 alleles with an average of three alleles per locus. Initially, the accessions clustered into two populations and an admixture group. Intra-population analysis revealed three and two statistically distinct subpopulations in Pop I and Pop II, respectively. The exotic collections were predominant in Pop I-A, Pop II-A and Pop II-B while the Indian accessions were preponderant in Pop I-B and Pop I-C. Pop I-B recorded the maximum magnitude of gene diversity and the highest number of alleles. The well-adapted Indian landraces could be deployed in future watermelon improvement programmes. The formulated core collection (n= 46; 23.71% of the entire collection studied) would ease in maintenance of the diversity present among indigenousCitrullussp. accessions; would ease trait search while exploring Indian diversity and can be pooled with other collection(s) to form a global core of watermelon.

Assessment of genetic variability for micronutrient content and agro-morphological traits in rice (Oryza sativa L.)

Assessment of rice genetic diversity is critical step for trait specific varietal development program. In the present study, a collection of 281 Indian germplasm accessions were evaluated for genetic diversity study using 30 agro-morphological characters and grain iron and zinc contents in brown and polished rice. To identify the pattern of relatedness and associations, cluster analysis and principal component analysis coupled with correlation were used. Cluster analysis grouped 281 accessions into six main groups. Cluster 4 is the largest and had accessions with higher yield, zinc and iron content. Six components of principal component analysis indicated 76.4% of the total variation. The Principal Component (PC)1 showed 19.05%, while, PC2, PC3, PC4, PC5 and PC6 exhibited 14.23%, 13.61%, 11.58%, 7.59%, and 6.71% variability, respectively. Among the germplasm, three accessions IC145407, IC145357 and IC248034 have shown significant iron and zinc content in polished rice along with desirable grain yield. The information presented here will be useful in the development of rice varieties with high yield and micronutrient content.

Screening of Some Selected Indian Maize Cultivars to Simulated Drought Condition

Drought is a major constraint to get an optimum yield of any crop under changing environment. A total of 12 Indian accessions of maize seedlings was screened initially by performing relative water content (RWC) under water deficit condition. Three (RJ-2020, BPCH-6, and EC-3161) landraces that showed a higher RWC than DTSYN11 were finally selected for further studies. Four landraces maintained RWC above 80% under 4th and 8th day stress periods. Higher contents of chlorophyll were recorded significantly in EC-3161 and in RJ-2020 as compared to DTSYN11 under the 8th day of stress. RWC showed a decline in BPCH-6 (72.54%) and in RJ-2020 (72.65%) and proline was significantly increased up to 10 and 13-fold, respectively. Therefore, this research has identified three unfamiliar maize landraces that possess the capacity to be drought tolerance when under water deficit and watering condition. In addition to their useful applications in breeding program, they are valuable resources to elucidate genetic profiling that enhance the capacity to exhibit drought tolerance in Indian maize cultivars.

Scale insect Melanaspis glomerata (Green) (Homoptera: Diaspididae) in world collection of Saccharum spontaneum L.

The status of the sugarcane scale Melanaspis glomerata (Green) (Homoptera: Diaspididae) in an international collection of Saccharum spontaneum L., maintained as a part of world sugarcane germplasm at the ICAR-Sugarcane Breeding Institute Research Centre, Kannur, Kerala state, India, was examined in 2016 and 2017. The scale appeared in May coinciding with cane formation and the infestation started increasing during the post-monsoon period (September–December) which continued until harvest (January). Scale infestation varied widely among the accessions of S. spontaneum in the two experimental years. Infestation rates (cane basis) were significantly higher in 2017 than in 2016. Infestation rate and intensity (internode basis) were positively correlated in 2017. When the 79 accessions examined were grouped into three categories on the basis of higher infestation rate in the two study years, 21 (26.6%) were placed in least susceptible, 38 (48.1%) in moderately susceptible and 20 (25.3%) in highly susceptible categories. The highest infestation rate (100.00%) was recorded in the accession US 56–10-14 and lowest (2.94%) in SES 106B; two accessions, namely SH 61–4-1 and SH 61–4-3 were totally free from infestation. Non-parametric analysis of infestation parameters indicated higher intensity in foreign than Indian accessions. Plant height was positively and number of internodes negatively correlated with infestation rate in the low infestation year (2016). Also, infestation rate (2016) was significantly higher in accessions with inconspicuous wax band than those with prominent wax band; intensity (2017) was significantly highest in accessions with conoid internode shape in comparison with cylindrical and obovate shapes. However, canopy and leaf characteristics did not influence attack rates.