A comparative study of Zn and Fe distribution in two contrasting wheat genotypes

Effect of zinc and iron interaction on their distribution was examined in two wheat genotypes (UP262 and UP2628) under foliar application of 0, 0.25 and 0.50% ZnSO4 solution tagged with 925 KBq of Zn65 pot-1 for Zn and 0, 0.5 and 1.0% FeSO4 solution tagged with 925 KBq of Fe59 pot-1 for Fe at 30, 60 and 90 days after planting. Maximum grain yield of UP2628 (2.7 g pot-1 ) was recorded at 0.5%ZnSO4+0%FeSO4 while that of UP262 (2.63 g pot-1 ) was recorded at 0.5%ZnSO4+1.0%FeSO4. The highest straw yield of UP2628 (2.75 g pot-1 ) was noted at 0.5% ZnSO4+1.0%FeSO4 while that of UP262 (2.91 g pot-1 ) with 0.5%ZnSO4+0.5%FeSO4. Application of 0.5% and 1.0% FeSO4 reduced the accumulation of 65Zn in all parts of both the varieties. Regarding the 59Fe accumulation, it was found to be decreased with the increased application of ZnSO4 solution from 0.25% and 0.5% as compared to without application of Zn. On comparing translocation efficiencies of both the varieties, UP2628 showed better translocation thus accumulated higher zinc and iron. Therefore, variety UP2628 can be used further for crop improvement programme

Silicon-mediated modulation of physiological attributes, and pollen morphology under normal and water-deficit conditions in rice (Oryza sativa L.)

Drought, in the changing climatic conditions of the world, is a major obstruction to rice production and productivity. Silicon has been recognized as a vital element advantageous in combating various environmental stresses in crops. Five genotypes of rice (Oryza sativa L.) were selected to investigate the regulation of superoxide dismutase (SOD), proline and malondialdehyde (MDA) under normal and water-deficit conditions when exogenously supplemented with silicon. A field study for two successive years was laid out with four treatments viz. Control (T1), Si fertilized (T2), Si + Drought stress (T3) and Drought stress (T4). Results displayed that silicon-supplemented rice plants under water-deficit conditions had a significantly enhanced SOD activity increasing from 34.85 U/g fresh wt/min in case of drought-inflicted plants to 61.08 U/g fresh wt/min for Si-supplemented drought-inflicted plants. The proline and MDA content was reduced by 42% and 40% in the case of Si-added drought-stressed plants. The pollen study also unveiled the beneficial effect of silicon to cope with drought stress, while shrinkage of pollens was observed in drought conditions

Transcriptome wide identification and validation of calcium sensor gene family in the developing spikes of finger millet genotypes for elucidating its role in grain calcium accumulation.

BACKGROUND: In finger millet, calcium is one of the important and abundant mineral elements. The molecular mechanisms involved in calcium accumulation in plants remains poorly understood. Transcriptome sequencing of genetically diverse genotypes of finger millet differing in grain calcium content will help in understanding the trait. PRINCIPAL FINDING: In this study, the transcriptome sequencing of spike tissues of two genotypes of finger millet differing in their grain calcium content, were performed for the first time. Out of 109,218 contigs, 78 contigs in case of GP-1 (Low Ca genotype) and out of 120,130 contigs 76 contigs in case of GP-45 (High Ca genotype), were identified as calcium sensor genes. Through in silico analysis all 82 unique calcium sensor genes were classified into eight calcium sensor gene family viz., CaM & CaMLs, CBLs, CIPKs, CRKs, PEPRKs, CDPKs, CaMKs and CCaMK. Out of 82 genes, 12 were found diverse from the rice orthologs. The differential expression analysis on the basis of FPKM value resulted in 24 genes highly expressed in GP-45 and 11 genes highly expressed in GP-1. Ten of the 35 differentially expressed genes could be assigned to three documented pathways involved mainly in stress responses. Furthermore, validation of selected calcium sensor responder genes was also performed by qPCR, in developing spikes of both genotypes grown on different concentration of exogenous calcium. CONCLUSION: Through de novo transcriptome data assembly and analysis, we reported the comprehensive identification and functional characterization of calcium sensor gene family. The calcium sensor gene family identified and characterized in this study will facilitate in understanding the molecular basis of calcium accumulation and development of calcium biofortified crops. Moreover, this study also supported that identification and characterization of gene family through Illumina paired-end sequencing is a potential tool for generating the genomic information of gene family in non-model species

List of domain, sub-cellular localization and instability index analysis of finger millet calcium sensor.

<p>C Chloroplast, i.e. the sequence contains cTP, a chloroplast transit peptide;</p><p>M Mitochondrion, i.e. the sequence contains mTP, a mitochondrial targeting peptide;</p><p>S Secretory pathway, i.e. the sequence contains SP, a signal peptide;</p><p>_ any other location.</p><p>List of domain, sub-cellular localization and instability index analysis of finger millet calcium sensor.</p

List of Primers designed from highly expressed genes from transcriptome data of high Ca containing genotype for qPCR analysis.

<p>List of Primers designed from highly expressed genes from transcriptome data of high Ca containing genotype for qPCR analysis.</p

Expression of 82 Calcium sensor genes in pooled spikes of GP-1 (Low calcium) and GP-45 (High calcium) genotype.

<p>The number indicated on each cell represents the log2 calculated FPKM values. FPKM values smaller than 1 were not calculated due to negative logarithm and they were stated as in the original data.</p

Pattern of calcium accumulation in developing spikes of GP-1 (Low calcium) and GP-45 (High calcium) grown under different concentration of exogenous calcium (0.1 mM, 5.0 mM, 10 mM & 20 mM).

<p>The different stages of developing spikes are S1 (spike emergence); S2 (pollination stage); S3 (dough stage) and S4 (maturation).</p

Phylogenetic tree of calcium sensor genes of rice and finger millet.

<p>Neighbor-joining tree was created using MEGA6 software with 1000 bootstrap using ORF sequences of rice and finger millet CaM and CaMLs, CBLs, CRKs, PEPRKs, CaMKs and CCaMK proteins. Eight groups were labelled as A, B, C, D, E, F, G and H.</p

Functional category of differentially expressed calcium sensor gene in finger millet.

<p>Functional category of differentially expressed calcium sensor gene in finger millet.</p

Multilevel consensus sequences for the MEME defined motifs of members of different calcium sensor genes.

<p>Multilevel consensus sequences for the MEME defined motifs of members of different calcium sensor genes.</p