A pinboard by
Mintu Ram Meena

Scientist, ICAR SBIRC


Sugarcane (Saccharam spp.) hybrids from alien species and genera has greatest biomass potential

Sugarcane (Saccharam spp.) hybrids derived from alien species and genera has greatest biomass potential. In the study, three group of Saccharum hybrids derived from diverse genetic background involving alien species and genera were used to evaluate their biomass potential under sub—tropical climate of India. First group hybrids- includes nine inter-generic hybrid (IGH) derived involving alien genera Erianthus arundinaceous. Second group hybrid – includes nine inter- specific hybrids (ISH) derived from S. barberi (Indian cane) and S. sinensis (Chinese cane) and third group hybrid- include six interspecific hybrid derived involving S. officinarum, S. spontaneum and S. robustum (wild species). These 24 clones were evaluated along with four commercial varieties as checks viz., Co 0238 and CoJ 64 in early and CoS 767 and CoS 8436 in midlate maturing during 2013-14 in a randomized block design with two replications. The observation on fresh stalk weight, stalk numbers were recorded on a plot basis. Data on juice brix %, sucrose % and purity % were estimated as per standard procedures. For estimating fibre%, five cane from each entry were crushed and bagasse weight were recorded before and after drying in oven. Dry matter, fresh biomass yield and dry biomass yield were estimated. The result of study indicated that Saccharum hybrid generally has more biomass potential compared to commercial varieties. Thirteen of the hybrids recorded significantly higher dry biomass yield than the experimental mean of 28.97 t ha-1. Among first group inter-generic hybrids, three hybrids viz., GU 07- 3849 (49.23 t ha-1), GU 07-3730 (37.96 t ha-1) and GU 07-3764 (37.54 t ha-1) had significantly higher value due to their Erianthus background and were superior over the population mean. Two ISH hybrid viz., KGS 2004-48 (41.69 t ha-1) and KGS 2004-60 (39.05 t ha-1) derived from BC progenies of S. barberi and S. sinensis, recorded higher biomass. In ISH hybrids with S.officinarum, S.spontaneum and S.robustum background, two hybrids 99-438 (37.81 t ha-1) and 99-81 (37.22 t ha-1) had higher dry biomass production. Fibre% had positive correlation with total dry matter (TDM) and TDM, fresh biomass, stalk weight and number were found to be positively correlated with dry biomass yield. References:

  1. Mohanraj K (2014) Biomass potential of noval interspecific hybrids involving improved clones of Saccharum. Industrial Crops and Products 53:128-132.

Epidemiology of Fusarium Diseases in Sugarcane: A New Discovery of Same Fusarium sacchari Causing Two Distinct Diseases, Wilt and Pokkah Boeng

Abstract: Sugarcane, an important field crop, is cultivated under tropical and subtropical regions around the world. Fusarium sacchari causing wilt, is a stalk disease, inflicting severe damage to the crop in India and other countries. Similarly, pokkah boeng (PB) a foliar disease caused by different species of Fusarium also infects the crop throughout the world. In India, both the diseases occur in different states in various sugarcane varieties. Although both diseases occur independently in the field, we recorded that they occur together in a plant. Hence, a detailed investigation was conducted to characterize different Fusarium isolates from wilt- and PB-affected sugarcane varieties by sequencing TEF1-α gene. Gene sequencing of 48 isolates revealed that 44 were of F. sacchari and the remaining four belonged to F. proliferatum. Of the four F. proliferatum, three were associated with PB and one with wilt. Almost all the 41 wilt-associated isolates belonged to F. sacchari. Investigation carried out to identify Fusarium isolates from the plants exhibiting both the wilt and the PB in two varieties Co 0238 and MS 901 revealed that only F. sacchari caused wilt and PB symptoms in both. Further, several varieties showed progressive disease severity through different phases of PB and that resulted in wilt development. The results clearly established for the first time that the same fungal pathogen systematically infects sugarcane plant and exhibits both the diseases.

Pub.: 14 Sep '17, Pinned: 20 Dec '17

Detection and characterization of Maize chlorotic mottle virus and Sugarcanemosaic virus associated with maize lethal necrosis disease in Ethiopia: an emerging threat to maize production in the region

Abstract: Maize Lethal Necrosis Disease (MLND) develops from synergistic co-infection by Sugarcane mosaic virus and Maize chlorotic mottle virus. The disease causes symptoms ranging from leaf tissue mottling and malformed ears to premature plant death. Information on the diversity and transmission of those viruses are limited in Ethiopia. No attempts were made to characterize and identify SCMV and MCMV strains of Oromia and Benishangul-Gumuz regions. The aim of this research was to study MLND responsible viruses via serological and molecular techniques. A total of 174 symptomatic maize leaf samples were collected. Using Double Antibody Sandwich-ELISA (DAS-ELISA), 43 samples showed strong reaction for MCMV antibody and only 14 samples were clearly positive for SCMV. Reverse transcriptase polymerase chain reaction (RT-PCR) technique revealed the presence of MCMV and SCMV in most samples. Analysis of the genetic diversity of MCMV and SCMV by sequencing the coat protein of all isolates shows strong homology with previous East African isolates deposited in the GenBank. The phylogenetic analysis indicated that the virus isolates are highly similar with each other. In conclusion, this study unequivocally confirmed the association of MCMV and SCMV with MLND in the investigated areas and for the first time provided information on the genetic variability by sequence analysis of several Ethiopian samples. Since the risk posed by MLND in the investigated area is high, there is an urgent need for developing integrated management options for controlling the disease.

Pub.: 20 Apr '17, Pinned: 20 Dec '17

Identification and Characterization of microRNAs from Saccharum officinarum L by Deep Sequencing

Abstract: In modern sugarcane cultivars, around 70–80% of the genetic information originates from Saccharum officinarum, which contributed important sugar content traits. Although several studies have identified microRNAs in Saccharum hybrids, they have not yet been studied in S. officinarum. In this study, by deep sequencing and in silico approaches, 268 miRNA candidates were predicted in S. officinarum, and 52 were found to likely be real miRNAs based on our analysis with stringent criteria. Among these 52 miRNAs, 43 miRNAs from 26 miRNA families were found to have homologous miRNAs in public miRBase Release 21, and 9 miRNAs were identified to be novel in S. officinarum. Out of the 52 miRNAs, 6 were randomly chosen and verified by stem-loop RT-PCR. The 52 miRNAs were predicted to have 237 and 76 targets in sugarcane and sorghum, respectively, including auxin response factor, MADS-box transcription factor, zinc finger-like protein. MicroRNAs were found to be involved in critical sugarcane pathways, such as sucrose metabolism and cellulose metabolism. In addition, the first miRNA (sof-novel1) derived from the Saccharum chloroplast genome was identified. These results provide the foundation for future studies to distinguish the miRNAs from S. spontaneum and S. officinarum in Saccharum hybrid, and valuable information to further study the miRNA functions in Saccharum species.

Pub.: 22 Jul '17, Pinned: 20 Dec '17

Isolation, Transformation and Overexpression of Sugarcane SoP5CS Gene for Drought Tolerance Improvement

Abstract: Drought is one of the very important growth-limiting factors for sugarcane production in China. Δ1-pyrroline-5-carboxylate synthase (P5CS) is the rate-limiting enzyme in proline synthesis, and it plays an important role in plant response to drought stress. In this study, sugarcane P5CS (SoP5CS) gene was cloned and submitted in GenBank with the accession number KJ546350. The gene SoP5CS was 2151 bp in length, encoding 716 amino acids with a predicted molecular weight of 77.73 kDa and an isoelectric point of 6.14. The qRT-PCR analysis showed that the expression of SoP5CS was higher in leaf than in root and stalk, and strongly induced under ABA, PEG, NaCl and 4 °C treatments. The plant excessive expression vector of SoP5CS was built and transformed into sugarcane calli by Agrobacterium-mediated transformation method, and transgenic sugarcane plants were obtained. Under drought stress, some transgenic lines with overexpressed SoP5CS showed significantly higher in SoP5CS expression level, proline accumulation, abscisic acid content, superoxide dismutase activity and relative water content but lower MDA content and chlorophyll (SPAD value) decrease as compared with the WT plants. Moreover, all the transgenic plants increased drought stress tolerance. Our findings indicated that SoP5CS plays an important role in response to abiotic stresses and overexpression of SoP5CS can improve drought tolerance in transgenic sugarcane plants.

Pub.: 15 Nov '17, Pinned: 20 Dec '17

Assessment of genetic diversity in Colletotrichum falcatum Went accessions based on RAPD and ISSR markers

Abstract: Publication date: Available online 22 November 2017 Source:Journal of Genetic Engineering and Biotechnology Author(s): Prittesh Patel, B.K. Rajkumar, Preeti Parmar, Rusabh Shah, R. Krishnamurthy Sugarcane is susceptible to red rot disease caused by phytopathogenic fungus Colletotrichum falcatum Went which ultimately affect the economy of farmers as well as sugar based industry. One of the various ways to control this devastating disease is to develop disease resistance sugarcane cultivar and this requires the complete understanding of genetic makeup of pathogen. Although South Gujarat is well known sugarcane cultivating area, less published data can be found about PCR-based genetic diversity in prevalent C. falcatum accessions. So, present investigation aims at finding molecular variation among the ten accessions of C. falcatum using RAPD and ISSR molecular markers. A total of 35 RAPD and 39 ISSR primers were screened across 10 C. falcatum accessions, of which 15 RAPD and 21 ISSR primers have showed consistent amplification. Statistics related to genetic variation were estimated using NTSYS-PC by means of Dice’s coefficient. The results revealed 80.6% and 68.07% polymorphism and similarity coefficient ranged from 0.43 to 0.91 and 0.73 to 0.93 in RPAD and ISSR analysis respectively. The dendrogram generated using RAPD, ISSR and combined RAPD-ISSR grouped accessions into different clusters which reveal considerable level molecular variation among the C. falcatum accessions. It is also evident from PCA plots that accessions are rather dispersed with tested marker systems indicating good genetic base. So, in nut shell, we found considerable genetic variation and relatedness within C. falcatum accessions collected from different areas of south Gujarat, India using RAPD and ISSR markers.

Pub.: 01 Dec '17, Pinned: 20 Dec '17

Hormetic Response by Silver Nanoparticles on In Vitro Multiplication of Sugarcane (Saccharum spp. Cv. Mex 69-290) Using a Temporary Immersion System.

Abstract: Hormesis is considered a dose-response phenomenon characterized by growth stimulation at low doses and inhibition at high doses. The hormetic response by silver nanoparticles (AgNPs) on in vitro multiplication of sugarcane was evaluated using a temporary immersion system.Sugarcane shoots were used as explants cultured in Murashige and Skoog medium with AgNPs at concentrations of 0, 25, 50, 100, and 200 mg/L. Shoot multiplication rate and length were used to determine hormetic response. Total content of phenolic compounds of sugarcane, mineral nutrition, and reactive oxygen species (ROS) was determined.Results were presented as a dose-response curve. Stimulation phase growth was observed at 50 mg/L AgNPs, whereas inhibition phase was detected at 200 mg/L AgNPs. Mineral nutrient analysis showed changes in macronutrient and micronutrient contents due to the effect of AgNPs. Moreover, AgNPs induced ROS production and increased total phenolic content, with a dose-dependent effect.Results suggested that the production of ROS and mineral nutrition are key mechanisms of AgNP-induced hormesis and that phenolic accumulation was obtained as a response of the plant to stress produced by high doses of AgNPs. Therefore, small doses of AgNPs in the culture medium could be an efficient strategy for commercial micropropagation.

Pub.: 15 Dec '17, Pinned: 20 Dec '17

Molecular Characterization and Co-expression Analysis of the SnRK2 Gene Family in Sugarcane (Saccharum officinarum L.).

Abstract: In plants, both abscisic acid (ABA) dependent and independent pathways form the basis for the response to environmental stresses. Sucrose non-fermenting 1-related protein kinase 2 (SnRK2) plays a central role in plant stress signal transduction. However, complete annotation and specific expression patterns of SnRK2s in sugarcane remain unclear. For the present study, we performed a full-length cDNA library survey of sugarcane, thus identifying ten SoSnRK2 genes via phylogenetic, local BLAST methods, and various bioinformatics analyses. Phylogenetic analysis indicated division of SoSnRK2 genes into three subgroups, similar to other plant species. Gene structure comparison with Arabidopsis suggested a unique evolutionary imprint of the SnRK2 gene family in sugarcane. Both sequence alignment and structural annotation provided an overview of the conserved N-terminal and variations of the C-terminal, suggesting functional divergence. Transcript and transient expression assays revealed SoSnRK2s to be involved in the responses to diverse stress signals, and strong ABA induction of SoSnRK2s in subgroup III. Co-expression network analyses indicated the existence of both conserved and variable biological functions among different SoSnRK2s members. In summary, this comprehensive analysis will facilitate further studies of the SoSnRK2 family and provide useful information for the functional validation of SoSnRK2s.

Pub.: 17 Dec '17, Pinned: 20 Dec '17

Fingerprinting by amplified fragment length polymorphism (AFLP) and barcoding by three plastidic markers in the genus Wolffiella Hegelm

Abstract: Amplified fragment length polymorphism (AFLP) fingerprinting and three different plastidic DNA regions (rpl16, rps16, atpF-atpH) were used to investigate species identity in the genus Wolffiella. For this purpose, clones (67 in total) belonging to all ten species were selected. Almost all the species were represented by more than one clone. The fingerprinting technique, AFLP, clearly distinguished the species, W. caudata, W. gladiata, W. neotropica, W. rotunda, and W. welwitschii. Apart from confirming the molecular identity of these five species, the plastidic markers could delineate two additional species, W. hyalina and W. denticulata, although the conclusion concerning the latter is restricted by the availability of only one clone. The efficiency of the plastid-derived markers in identifying the number of species-specific clusters followed the sequence rps16 > rpl16 > atpF-atpH. The species W. lingulata, W. oblonga, and W. repanda could not be identified by any of the molecular methods presented here, but could be strictly defined on a morphological basis. In several clones, high amounts of genetic admixtures between different species were detected. Further, simulation studies demonstrated that these clones are genetic hybrids. This might be one of the obstacles in molecular identification of species in the genus Wolffiella.

Pub.: 14 Dec '17, Pinned: 20 Dec '17

Marker assisted breeding for introgression of opaque-2 allele into elite maize inbred line BML-6

Abstract: Publication date: October 2017 Source:Acta Ecologica Sinica, Volume 37, Issue 5 Author(s): M.S.R. Krishna, M. Surender, S. Sokka Reddy Improvement of QPM (Quality Protein Maize) along with high content of lysine and tryptophan had foremost importance in maize breeding programme. The efficient and easiest way of developing QPM hybrids was of backcross breeding in marker aided selection. Hence the present investigation was aimed with an endeavour to convert elite maize inbred line BML-6 into QPM line. CML-181 was identified to be a donor variety as it revealed high-quality polymorphism with BML-6 for opaque-2 gene specific marker umc1066. Non-QPM inbred line BML-6 was crossed with QPM donor CML-181 and produced F1 followed by BC1F1 and BC2F1 population was developed. Foreground selection was carried out with umc1066 in F1, and selected plants were used for BC1F1 and BC2F1 populations. Two hundred plants were screened in both BC1F1 and BC2F1 population with umc1066 for foreground selection. The selected plants were screened for foreground selection with amino acid modifiers. Foreground selected plants for both opaque-2 and amino acid modifiers were screened for background selection for BML-6 genome. Recurrent parent genome (RPG) was determined for BC2F1 population plants. Three plants have shown with RPG 90–93% in two generation back cross population. Three selected BC2F2 populations were screened for foreground and back ground selection followed by agronomical and biochemical evaluation. The QPM converted version of BML-6 contains 0.97% of tryptophan and 4.02% of lysine concentration in a protein. Agronomical and biochemical screened BC2F2 plants were selfed for BC2F3. QPM version of BML-6 line can be used for the development QPM version of maize single cross hybrids.

Pub.: 05 Nov '17, Pinned: 20 Dec '17

Genetic, morphological, and spectral characterization of relictual Niobrara River hybrid aspens (Populus × smithii).

Abstract: Aspen groves along the Niobrara River in Nebraska have long been a biogeographic curiosity due to morphological differences from nearby remnant Populus tremuloides populations. Pleistocene hybridization between P. tremuloides and P. grandidentata has been proposed, but the nearest P. grandidentata populations are currently several hundred kilometers east. We tested the hybrid-origin hypothesis using genetic data and characterized putative hybrids phenotypically.We compared nuclear microsatellite loci and chloroplast sequences of Niobrara River aspens to their putative parental species. Parental species and putative hybrids were also grown in a common garden for phenotypic comparison. On the common garden plants, we measured leaf morphological traits and leaf-level spectral reflectance profiles, from which chemical traits were derived.The genetic composition of the three unique Niobrara aspen genotypes is consistent with the hybridization hypothesis and with maternal chloroplast inheritance from P. grandidentata. Leaf margin dentition and abaxial pubescence differentiated taxa, with the hybrids showing intermediate values. Spectral profiles allowed statistical separation of taxa in short-wave infrared wavelengths, with hybrids showing intermediate values, indicating that traits associated with internal structure of leaves and water absorption may vary among taxa. However, reflectance values in the visible region did not differentiate taxa, indicating that traits related to pigments are not differentiated.Both genetic and phenotypic results support the hypothesis of a hybrid origin for these genetically unique aspens. However, low genetic diversity and ongoing ecological and climatic threats to the hybrid taxon present a challenge for conservation of these relictual boreal communities.

Pub.: 17 Dec '17, Pinned: 20 Dec '17

Enhanced electrochromic performance of WO3 hybrids using polymer plasma hybridization process

Abstract: Publication date: January 2018 Source:Synthetic Metals, Volume 235 Author(s): Esin Eren, Ceyda Alver, Gozde Yurdabak Karaca, Emre Uygun, Aysegul Uygun Oksuz A series of electrochromic hybrid materials were synthesized with in-situ polymerization of aniline, 2-fluoroaniline and N-methylaniline onto tungsten trioxide (WO3) powders using a rotating capacitively coupled radio frequency (rf) plasma process. The materials were characterized by means of scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray diffraction analysis (XRD). Thin films of tungsten trioxide/polyaniline (WO3/PANI), tungsten trioxide/poly(2-fluoroaniline) (WO3/PFANI) and tungsten trioxide/poly(n-methylaniline) (WO3/PMANI) hybrid powders were obtained by e-beam technique onto flexible conducting polyethylene terephthalate electrodes for electrochromic works. The optical and electrochromic properties of WO3 hybrids-based ECDs were investigated by optical and electrochemical measurements. It is observed that electrochromic performance of hybrid films has changed as depending on electron acceptor or donor properties of substituent group onto PANI chain. The results of flexible electrochromic devices (ECDs) indicated that WO3/PMANI hybrid-based ECD has a high optical contrast of 49% at 750nm, reversible coloration with efficiency of 361cm2/C and fast switching times (bleaching time: 1.41s, coloration time: 0.67s). Graphical abstract

Pub.: 17 Dec '17, Pinned: 20 Dec '17

2G ethanol from the whole sugarcane lignocellulosic biomass.

Abstract: In the sugarcane industry, large amounts of lignocellulosic residues are generated, which includes bagasse, straw, and tops. The use of the whole sugarcane lignocellulosic biomass for the production of second-generation (2G) ethanol can be a potential alternative to contribute to the economic viability of this process. Here, we conducted a systematic comparative study of the use of the lignocellulosic residues from the whole sugarcane lignocellulosic biomass (bagasse, straw, and tops) from commercial sugarcane varieties for the production of 2G ethanol. In addition, the feasibility of using a mixture of these residues from a selected variety was also investigated.The materials were pretreated with dilute acid and hydrolyzed with a commercial enzymatic preparation, after which the hydrolysates were fermented using an industrial strain of Saccharomyces cerevisiae. The susceptibility to enzymatic saccharification was higher for the tops, followed by straw and bagasse. Interestingly, the fermentability of the hydrolysates showed a different profile, with straw achieving the highest ethanol yields, followed by tops and bagasse. Using a mixture of the different sugarcane parts (bagasse-straw-tops, 1:1:1, in a dry-weight basis), it was possible to achieve a 55% higher enzymatic conversion and a 25% higher ethanol yield, compared to use of the bagasse alone. For the four commercial sugarcane varieties evaluated using the same experimental set of conditions, it was found that the variety of sugarcane was not a significant factor in the 2G ethanol production process.Assessment of use of the whole lignocellulosic sugarcane biomass clearly showed that 2G ethanol production could be significantly improved by the combined use of bagasse, straw, and tops, when compared to the use of bagasse alone. The lower susceptibility to saccharification of sugarcane bagasse, as well as the lower fermentability of its hydrolysates, can be compensated by using it in combination with straw and tops (sugarcane trash). Furthermore, given that the variety was not a significant factor for the 2G ethanol production process within the four commercial sugarcane varieties evaluated here, agronomic features such as higher productivity and tolerance of soil and climate variations can be used as the criteria for variety selection.

Pub.: 17 Mar '15, Pinned: 10 Aug '17

Comprehensive assessment of sugarcane straw: implications for biomass and bioenergy production

Abstract: Sugarcane straw, consisting of green tops and dry leaves, can be maintained on fields to improve soil quality, or harvested for bioenergy production. The optimum option between these two uses is still uncertain and requires further study. This study, conducted across three crop cycles, provides an assessment of the moisture, nutrients, ash, extractives, cellulose, hemicelluloses, and lignin contents of four sugarcane varieties across seven regions of south-central Brazil. Suitability of the straw fractions for nutrient recycling, bioelectricity, and second-generation ethanol production were also evaluated. Results showed that the sugarcane straw yield (dry mass) was 14.0 Mg ha−1, and the ratio of dry straw/fresh stalk was 12%. The composition of green tops and dry leaves differed consistently across varieties, sites, and crop cycles. Dry leaves represented 60% of the straw, but green tops contained about 70% of the total N, P, and K content. Therefore, green tops recycled up to four times more nutrients than dry leaves. Green tops also had six times higher moisture and greater chlorine content which decreased the mill process efficiency. In turn, dry leaves had higher lignin, cellulose, and hemicelluloses content, greater heating value (higher: 17.3 MJ kg−1; lower: 15.6 MJ kg−1) and tended to be a better second-generation ethanol production feedstock. Overall, the results show that it is preferable to use dry leaves for bioenergy production while leaving green tops on the field for nutrient recycling. This study pointed out that more efficient methods for separating these fractions in the field need to be developed. © 2017 Society of Chemical Industry and John Wiley & Sons, Ltd

Pub.: 15 Mar '17, Pinned: 10 Aug '17