Sugarcane Samples Research Articles

Identification of 16SrXI phytoplasmas in sugarcane and alternative hostplants in Karnataka, India

Sugarcane crop is severely affected by diverse phytoplasma-associated diseases worldwide. Symptomatic sugarcane, eggplant and cluster bean together with weeds such as false daisy, Croton sparsiflorum, and Parthenium hysterophorus samples were collected at Khanapur village in Karnataka, India in 2018. The molecular analyses of the samples allowed to identify the presence of 16SrXI phytoplasma group after nested PCR amplification of the 16S rRNA gene followed by RFLP and sequencing analyses. The virtual and real RFLP analysis of the 16S rRNA gene sequence suggested its classification in a new ribosomal subgroup tentatively named 16SrXI-G. Amplification of secA and tuf genes from the sugarcane samples also confirmed the presence of 16SrXI group phytoplasmas in sugarcane and other host plant species in India and indicate their close relationship with sugarcane white leaf phytoplasmas from Sri Lanka and Vietnam. The identification of this phytoplasma strain in sugarcane, brinjal, cluster beans and weeds, in and around sugarcane fields in Karnataka, is an important information that should be employed to help the disease management aimed to reduce the phytoplasma incidence and economic losses in sugarcane.

The Wheat Dwarf India Virus-Betasatellite Complex Has a Wider Host Range Than Previously Reported

Wheat dwarf India virus (WDIV) and associated alphasatellite and betasatellite have been documented to infect wheat (Triticum aestivum). Here, we report, for the first time, presence of WDIV and the associated Ageratum yellow leaf curl betasatellite (AYLCB) in barley (Hordeum vulgare) and sugarcane (Saccharum officinarum) in addition to wheat. However, surprisingly, the previously reported alphasatellites were not detected in the WDIV-positive barley, sugarcane, and wheat samples. The virus and betasatellite detected from barley, sugarcane, and wheat showed high levels of sequence identity to the previously reported WDIV and AYLCB. The study shows that WDIV may have much wider host range than previously documented.

A threat to sandalwood cultivation in the naturalised Marayoors andalwood reserve (Kerala, India) through single and mixed phytoplasma infections

The forest of Southern India, especially in the states of Karnataka, Tamil Nadu and Kerala are recognised for natural populations of sandalwood contributing 90% of its distribution in India. The sandal spike disease (SSD) of sandalwood is known to be associated with the presence of aster yellows (‘Candidatus Phytoplasma asteris’, 16SrI-B). The recent survey and collection of the symptomatic sandalwood samples from the Marayoor sandalwood reserve of Kerala state confirmed the presence of this phytoplasma; however, also 16SrXI-B phytoplasmas were identified. These phytoplasmas were present in single or in mixed infection in the collected sandalwood, sugarcane and Indian gooseberry samples from this area. This study is the first report of 16SrXI-B phytoplasmas in sugarcane in Kerala of witches’ broom disease in Indian gooseberry associated with aster yellows phytoplasmas and the first report of 16SrXI-B phytoplasma presence in SSD plants. These findings unveil serious threat to existing sandalwood and sugarcane cultivation in the Marayoor sandalwood reserve area, and demand a thorough investigation on phytoplasma insect vectors to efficiently manage these diseases associated with phytoplasmas.

Analysis of aroma components from sugarcane to non-centrifugal cane sugar using GC-O-MS

A total of 84 volatile aroma components were determined in the 9 samples of sugarcane to non-centrifugal sugar (NCS), including 15 alcohols, 12 aldehydes, 10 ketones, 17 carboxylic acids, 11 pyrazines, 7 phenols, 3 esters, 3 hydrocarbons, and 2 sulfur compounds. Of these compounds, 10 were with high flavor dilution (FD) factors based on the aroma extract dilution analysis (AEDA). 4-Hydroxy-2,5-dimethyl-3(2H)furanone exhibited the highest FD factor of 2187, followed by (E)-2-nonenal, 2-hydroxy-3-methyl-2-cyclopentene-1-one, and 4-allyl-2,6-dimethoxyphenol with a FD factor of 729. The odor compounds showed no significant change and were similar to that of sugarcane during the first four steps in the production of non-centrifugal cane sugar. In the middle three stages, the heating slightly affected the aroma composition. Additionally, a prolonged period of high-temperature heating, lead to the production of the Maillard reaction products, such as pyrazines, pyrroles, and furans, differentiating the step to be unique from the previous seven stages. However, the content of the NCS odorants was significantly reduced due to the loss of odor compounds during the drying process.

A new phytoplasma strain associated with the sugarcane white leafdisease in Vietnam

Sugarcane white leaf (SCWL) disease is one of the most important diseases of sugarcane in Vietnam. The presence of phytoplasmas in phloem tubes of infected plants was confirmed by DAPI staining. A nested PCR assay using R16mF2/R16mR1 and R16F2n/R16R2 primer pairs amplified products with approximate length of 1,250 bp from the symptomatic sugarcane samples. The sequence analysis indicated that the phytoplasma strains from Khanh Hoa province shared 100% sequence identity with previously sequenced SCWL phytoplasma strains that were related to ‘Candidatus Phytoplasma oryzae’ (16SrXI). The virtual RFLP patterns of a 1,127 bp sequence obtained with the restriction enzymes BfaI, BstUI, EcoRI, HaeIII, HinfI, HpaI, RsaI and TaqI indicate that this SCWL-associated phytoplasma from Vietnam is a different strain from those in the 16SrXI described ribosomal subgroups. The two insect species, Matsumuratettix hiroglyphicus and Yamatotettix flavovittatus, identified as the vectors of SCWL in Thailand, were identified and found to be infected also in the SCWL symptomatic fields in Vietnam. The transmission experiments from SCWL-infected leafhoppers to healthy sugarcane and to insect feeding medium failed, suggesting that the infected planting material is the major transmission manner of SCWL disease in Vietnam.

Occurrence and Molecular Identification of Wild Yeasts from Jimma Zone, South West Ethiopia.

Yeasts are common inhabitants of most fruit trees’ rhizospheres and phyllospheres. Wild yeasts are the major driving force behind several modern industrial biotechnologies. This study focused on determining the occurrence and frequency of wild yeasts associated with domestic and wild edible tree barks, fruits, and rhizosphere soil samples collected over two seasons (i.e., spring and summer) in South West Ethiopia. A total of 182 yeast strains were isolated from 120 samples. These strains belonged to 16 genera and 27 species as identified based on the sequence analysis of the D1/D2 domain of the large subunit (26S) ribosomal RNA gene. Candida blattae, Pichia kudriavzevii, Candida glabrata, Saccharomyces cerevisiae, and Candida humilis were the most dominant yeast species isolated from the bark samples. Only Pichia kudriavzevii was regularly detected from the bark, rhizosphere, fruit, and sugarcane samples. The retrieval of yeasts from bark samples was more frequent and diverse than that of soil, fruits, and sugarcane. The frequency of detection of yeasts during the spring was significantly higher than in the summer season. However, there was no significant seasonal variation in the frequency of detection of yeast species between the rhizosphere and phyllosphere samples.

Genetic variation and characterization of the sucrose synthase 2 gene (Sus2) in sugarcane based molecular markers

Abstract. Kasiamdari RS, Febiansi D, Prabowo H, Aristya GR, Musthofa A. 2019. Genetic variation and characterization of the sucrose synthase 2 gene (Sus2) in sugarcane based molecular markers. Biodiversitas 20: 3087-3096. Sugarcane (Saccharum spp.) genotype is one of the sugar-producing plants and an important commodity to support the community’s economy. Plant breeders continuously cross-breed these plants to obtain cultivars with desirable traits to produce a variety of new phenotypes. An analysis of variation at gene-level is carried out as an important step in plant breeding programs. The purpose of the present study was to determine genetic variation and characterize the sucrose synthase 2 gene (Sus2) based on molecular markers. Twenty sugarcane cultivars were sampled from Indonesian Sweetener and Fiber Crops Research Institute (BALITTAS) Malang and four sugarcane cultivars from PT. Madu Baru in Polosio A Plantation, Poncosari, Srandakan, Bantul Regency, Yogyakarta. DNAs were amplified using two primer pairs, i.e. AI and SMC226CG. The genetic variations of the twenty-four sugarcane cultivars were analyzed by constructing a dendrogram of the Amplified DNA using Multi-Variate Statistical Package (MVSP) software. The results showed that there were three large clusters, namely Cluster A consisting of ‘PS 865’, ‘PS 951’, ‘PS 921’, and ‘PS 58’, with a similarity index of 57%; Cluster B consisting of the sugarcane ‘Kentung’, with a similarity index of 33%; and cluster C consisting of the sugarcane ‘PSDK 923’, ‘PSBM 901’, ‘TLH 2’, ‘BL’, ‘PSJT 941’, ‘KK’, ‘PS 80.1649’, ‘PSCO 902’, ‘PS 80,910’, ‘PS 882’, ‘PS 862’, ‘PS 851’, ‘PS 881’, ‘PS 865’, ‘PS 384’, ‘VMC 76-16’, ‘BZ 132’, ‘PS 891’, ‘PS 41’ with a similarity index of 60%. Polymorphisms occurred after the DNAs were amplified and after the bands appeared in heterozygous and homozygous individuals. In sugarcane, the Sus2 gene when detected by the molecular marker primer AI showed high-sucrose sugarcane; whereas the Sus2 gene detected by the primer SMC226CG showed low-sucrose sugarcane. Results of the present study showed that all sugarcane samples were detected as having low sucrose except Bulu Lawang and Kentung cultivars.

Protective activity of sweet sorghum and sugarcane syrups against oxidative stress induced by cadmium in albino rats

The present study was designed to investigate the effect of sweet sorghum and sugarcane syrups as antioxidants on oxidative stress biomarkers and the lipid profile i.e. serum total triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and low density lipoproteins cholesterol (LDL-C)) in male rats. Cadmium was received orally to rats daily at a dose of 10mg/L in drinking water. Rats were divided into four groups,-eight rats for each- as follow: (I) control group, (II) cadmium treated group, (III) sweet sorghum syrup solution (500 ppm) once daily at a dose of 1 ml/kg body weight of cadmium acetate solution, (IV) sugarcane syrup solution (500 ppm) and cadmium acetate solution. Bioactive compounds of syrups under investigation were identified, total phenolic and flavonoid contents were determined as well. Results cleared that the effect of variation in varieties on total phenol (mg GAE/ml sample) and antioxidant activity determined by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) assay of syrup was significant (P≤0.05) while it was not significant (P˃0.05) on total flavonoid (mg CE/ml sample).The highest total phenolic content was recorded by sweet sorghum syrup (1.87 mg GAE/ml sample) meanwhile, total flavonoid content varied between (1.09 and 1.36 mg CE/ml sample). Results also cleared that G.T.54-9 sugarcane and Rex sweet sorghum syrup samples exhibited significant (P≤0.05) scavenging activity compared to commercial sugarcane sample that gave lower scavenging activity (97.16, 96.07 and 74.22, respectively).Sweet sorghum and sugarcane syrups significantly affected (P≤0.05) absolute weight of organs and relative weight of both heart and kidney, while the effect on relative weight of liver was not significant (P>0.05). The treatment of sweet sorghum and sugarcane syrups during cadmium acetate administration in rats led to reduction in alanine transaminase (ALT), aspartate transaminase (AST), antioxidant enzymes, urea, creatinine and biomarkers in rat livers, like reduced glutathione , catalase ,malondialdehyde ,serum total triglyceride, total cholesterol, high density lipoprotein cholesterol and low density lipoproteins cholesterol back near to normal when compared to control rats. In general, the treatment with sugarcane syrup reduced the cadmium acetate induced hepatotoxicity in rats.

Comparing the chemical composition of dietary fibres prepared from sugarcane, psyllium husk and wheat dextrin

A dietary fibre prepared from sugarcane stalk was compared with psyllium husk and wheat dextrin. In contrast to the other dietary fibres, sugarcane fibre was found to contain significant amounts of insoluble dietary fibre (73–86%), lignin (18.66–20.23%), and rare minerals such as chromium (0.67–2.54 mg/100 g) and manganese (1.07–2.34 mg/100 g). Analysis of the ethanol extract also detected compounds with antioxidant activity. Characterisation of five sugarcane fibres prepared from selected strains, harvest periods (growth or storage phase), and processing conditions showed these factors influenced the final composition. Furthermore, using in vitro digestion, we found that potassium, magnesium, chromium, and zinc in were bioaccessible in sugarcane samples. Also, sodium was shown to bind to the sugarcane fibre potentially indicating bile salt binding activity. Results from this study support the use of sugarcane as a source of dietary fibre in functional foods.

<i>Lactobacillus plantarum</i> LPBR01 as inoculant in sugarcane silage

Sugar cane is highly productive (dry matter.hectare-1), but after ensiling process nutritional quality is affected, thus additives are needed to control or minimize losses. This study aimed to evaluate if Lactobacillus plantarum LPBR01 strain used as silage inoculant for sugar cane can control fermentation losses. Sugar cane samples (72) were divided in two treatments with three replicates, control (no Lactobacillus) and treatment silage with Lactobacillus (106 CFU g-1 of silage). Nutritional composition of samples in different periods of fermentation (0, 7, 15, 30 and 45 days) was estimated by determining levels of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HEM), mineral matter (MM) and acid detergent lignin (ADL). Fermentative profile of the silage was characterized by determining sugars, ammoniacal nitrogen, acidity and pH at 0, 12, 24, 36, 48, 60 and 72 hours. Inoculation of sugar cane silage with Lactobacillus plantarum LPBR01 strain presented no significant results (p ≤ 0, 5) however, interaction between treatment and day (p ≤ 0, 5) could be observed for the levels of ADF. The Lactobacillus plantarum LPBR01 strain was not efficient to control the fermentation losses that occur in the silages of sugar cane at the concentration used in this study.

ENDOPHYTIC BACTERIA ASSOCIATED WITH SUGARCANE AND ITS POTENTIAL TO SUPPRESS SPORISORIUM SCITAMINEUM, THE CAUSAL FUNGAL PATHOGEN OF SMUT DISEASE

Bacterial endophytic ubiquitously colonize the internal tissues of the plant. The purpose of this study was to isolate and identify the endophytic bacteria from sugarcane stalks which have antagonistic activity against Sporisorium scitamineum, the causal pathogen of sugarcane smut disease, and to study their activity to produce some secondary metabolites i.e. enzymes and growth-promoters. Sugarcane samples were collected from five governorates in Upper-Egypt namely, Giza, Beni-Suef, Sohag, Qena, and Luxor. A total of 240 isolates of endophytic bacteria were isolated from 160 samples of healthy sugarcane stalks (variety GT-54-9). Isolated endophytes were screened for its antagonistic activity against S. scitamineum, in vitro, using dual culture method. Only, 62 isolates showed different degrees of antagonistic activity. Ten isolates of endophytic bacteria were selected to study their potential to produce enzymes (chitinase, β 1,3 glucanase, phenylalanine ammonia lyase) and growth-promoters (siderophores, indole acetic acid (IAA), salicylic acid (SA)). These isolates were pre-identified using the morphological and physiological properties according to Bergy's manual as Pseudomonas sp., Serratia sp., Enterobacteria sp., Herbaspirillium sp., Gluconacetobacter sp. Anabaenopsis sp. and Azospirillumsp. All endophetic bacteria produced β 1,3gluconase and indole acetic acid (IAA), while Pseudomonas sp. produced salicylic acid and phenylalanine ammonia lyase, Ana baenopsis sp. produced phenylalanine ammonia lyase, Gluconacetobacter sp. produced chitinase and Herbaspirillium sp. produced siderophore. Meanwhile, isolates of Anabaenopsis sp. and Pseudomonas sp. were the most effective to produce β 1,3glucanase and indole acetic acid compared with other entophytic bacteria.

Phenotypic and molecular characterization of diazotrophic bacteria associated with sugarcane in Bangladesh

The study was conducted with the intent to isolate and characterize endophytic and diazotrophic bacteria from stem and roots of sugarcane (Saccharum sp.) and from associated rhizosphere with a wider goal to develop bio-fertilizer. Twenty-one samples of bacteria were isolated from sugarcane samples obtained from the test field of Bangladesh Sugarcane Research Institute (BSRI), Pabna, and from cultivation field of Ruppur, Bangladesh. Out of 21 isolates, 11 were identified as members of the class Gammaproteobacteria (with one exception) and majority of them were Enterobacteriaceae. The isolates were characterized by determining their metabolic characteristics, stress factor tolerance, plant growth-promoting attributes, and molecular characteristics. The isolates were phenotypically diverse, retaining some characteristics of Enterobacteriaceae. A significant number of isolates produced indole acetic acid and iron-chelator siderophore. Majority of them also solubilized phosphorus. Among molecular characteristics, the nifH gene region of Enterobacteriaceae family was detected by PCR amplification. The PCR products of 16S rRNA and nifH gene of representative isolates were sequenced and phylogenetically analyzed. This study establishes that a significant percentage of the bacteria found in the sugarcane stem, root, and associated rhizosphere has the potential to fix atmospheric nitrogen and promote plant growth. Therefore, they may have the feasibility to be used as bio-fertilizer.

Genetic diversity and population structure of Sugarcane streak mosaic virus in Yunnan province, China

Sugarcane streak mosaic virus (SCSMV) is one of the most important pathogens associated with sugarcane mosaic disease. In recent years, the rapid spread of SCSMV in Yunnan province, China, has raised concerns. In this study, we analyzed 110 sugarcane samples with mosaic symptoms taken from main growing areas in Yunnan province. RT-PCR detection results showed that 94% samples were positive for SCSMV. We subsequently analyzed the genetic diversity and population structure of SCSMV based on the coat protein (CP) sequences of 48 isolates. The overall mean value of nucleotide diversity for all isolates was 0.01127 ± 0.00082. Phylogenetic analysis based on CP gene sequences showed that all the Chinese isolates were clustered into one group, showing a distinct geographic feature. Analysis of population structure showed that the population from this study is not genetically different from that in China, but is genetically different from populations from other countries. Our results suggest that SCSMV has become the main pathogen of sugarcane mosaic disease in Yunnan province, China and that the recent rapid spread of SCSMV in Yunnan is not due to the invasion of new SCSMV populations.

Development of a Reverse Transcription-Recombinase Polymerase Amplification Assay for Detection of Sugarcane Yellow Leaf Virus

Sugarcane yellow leaf virus (SCYLV, genus Polerovirus) is a harmful agent that causes sugarcane yellow leaf disease. Current methods for SCYLV detection present some limitations. In this study, a novel isothermal amplification assay, namely reverse transcription-recombinase polymerase amplification (RT-RPA), was developed to promote SCYLV detection for disease management. The assay was evaluated in terms of specificity, sensitivity, reliability, temperature limit, and time limit. The developed RT-RPA assay was highly specific and non-cross-reactive with Potato leafroll virus, which is a type of species in Polerovirus. This assay can also detect at least 103-fold diluted cDNA from a SCYLV-infected sugarcane leaf, and its sensitivity is tenfold lower than that of RT-polymerase chain reaction (PCR). The reliability of the proposed assay was examined by detecting field sugarcane samples via RT-RPA and RT-PCR assays. The RT-RPA assay showed the same results as those of RT-PCR assay, indicating that the former was highly reliable for SCYLV detection. Analysis of the temperature and time limits revealed a wide operating temperature range from 27 to 45 °C, which was easily reached, and a rapid assay duration of 20 min. In summary, the developed RT-RPA assay was rapid, specific, and reliable with acceptable sensitivity and easily reachable operating temperature and thus could be a promising tool for SCYLV diagnosis in sugarcane.

Moving-window bis-correlation coefficients method for visible and near-infrared spectral discriminant analysis with applications

The moving-window bis-correlation coefficients (MW-BiCC) was proposed and employed for the discriminant analysis of transgenic sugarcane leaves and [Formula: see text]-thalassemia with visible and near-infrared (Vis–NIR) spectroscopy. The well-performed moving-window principal component analysis linear discriminant analysis (MW-PCA–LDA) was also conducted for comparison. A total of 306 transgenic (positive) and 150 nontransgenic (negative) leave samples of sugarcane were collected and divided to calibration, prediction, and validation. The diffuse reflection spectra were corrected using Savitzky–Golay (SG) smoothing with first-order derivative ([Formula: see text]), third-degree polynomial ([Formula: see text]) and 25 smoothing points ([Formula: see text]). The selected waveband was 736–1054[Formula: see text]nm with MW-BiCC, and the positive and negative validation recognition rates ([Formula: see text]_REC[Formula: see text], [Formula: see text]_REC[Formula: see text] were 100%, 98.0%, which achieved the same effect as MW-PCA–LDA. Another example, the 93 [Formula: see text]-thalassemia (positive) and 148 nonthalassemia (negative) of human hemolytic samples were collected. The transmission spectra were corrected using SG smoothing with [Formula: see text], [Formula: see text] and [Formula: see text]. Using MW-BiCC, many best wavebands were selected (e.g., 1116–1146, 1794–1848 and 2284–2342[Formula: see text]nm). The [Formula: see text]_REC[Formula: see text] and [Formula: see text]_REC[Formula: see text] were both 100%, which achieved the same effect as MW-PCA–LDA. Importantly, the BiCC only required calculating correlation coefficients between the spectrum of prediction sample and the average spectra of two types of calibration samples. Thus, BiCC was very simple in algorithm, and expected to obtain more applications. The results first confirmed the feasibility of distinguishing [Formula: see text]-thalassemia and normal control samples by NIR spectroscopy, and provided a promising simple tool for large population thalassemia screening.

Perancangan Sistem Hidrolik pada Unit Mobile Core Sampler

Sugarcane core sampler is a plantation equipment sector which collect sugar cane samples and determining of rendemen in sugarcane. Sugarcane core sampler is a new product made by PT. United Tractors Pandu Engineering to solve problem about determining of individual rendemen in sugarcane at sugar mill. In operation Sugarcane Core Sampler uses a hydraulic system as the prime mover, either to raise the platform, take samples of cane and push it out of the probe cylinder. In order for the hydraulic system to work optimally, it is necessary to design and calculate the specification of components to be used on tilting cylinders, ejector, hydraulic pump, and reservoir (hydraulic tank). It also conducted a discussion of the difference between the Core Sampler Sugarcane fixed and mobile models. From the calculation results obtained inside diameter tilting cylinder is Ø100 mm with rod cylinder Ø56 mm, inside diameter of ejector cylinder is Ø32 mm with rod cylinder Ø1 8mm. At the biggest pump flow required is 51.81 lpm and displacement 43 cc/rev, from result of calculation hence specified pump which used is pist on pump type with displacement 41 cc/rev. For hydraulic tank capacity requiredon all hydraulic systems is 177 liters.

Determination and dissipation of fipronil and its metabolites in/on sugarcane crop

ABSTRACTFipronil has label claim for managing shoot borer and root borer of sugarcane. The dissipation and metabolism of fipronil in/on sugarcane crop have been studied under tropical field condition by employing a modified quick, easy, cheap, effective, rugged and safe sample preparation method and gas chromatography equipped with electron capture detector. The method could provide 90.27–98.97% recoveries of target analytes from cane leaves and stem with relative standard deviations of less than 5%. The sulphide, desulfinyl and sulfone metabolites of fipronil were detected along with the parent compound even in the 0-day samples of sugarcane leaves and stem collected 2 h post-foliar spraying. The total residues comprising fipronil and its three major metabolites got dissipated to 4.366 µg/g from the initial deposit of 12.977 µg/g within a day after foliar spray. Fipronil sulphide and fipronil desulfinyl were the major metabolites on sugarcane crop. The residues (both parent compound and total residues) reached below the detectable level of 0.005 µg/g on 7 and 15 days after treatment on stem and leaves, respectively. Half-life of fipronil was less than a day on sugarcane crop. The total residues had the half-life of 1.66 and 0.91 days on leaves and stem, respectively.

Use of secA Gene for Characterization of Phytoplasmas Associated with Sugarcane Grassy Shoot Disease in India

Surveys of commercial sugarcane varieties were conducted to the phytoplasma disease incidence in eight major sugarcane growing states of India (Uttarakhand, Uttar Pradesh, Maharashtra, Bihar, Assam, Chhattisgarh, Haryana and Tamil Nadu) during 2014–2015. Leaves from 24 symptomatic sugarcane plants of eight varieties showing grassy shoot and chlorosis symptoms, and of 8 non-symptomatic plants were collected and analyzed for phytoplasma presence using 16S rRNA and secA gene-specific primers. Amplification of 1.8- and 1.2-kb products using nested primers (P1/P7 and R16F2n/R16R2) of 16S rRNA gene and 880- and 480-bp products using secA gene-specific primer pairs (SecAfor1/SecArev3 and SecAfor2/SecArev3) was obtained for all the 24 symptomatic sugarcane samples. Pairwise sequence comparison, phylogenetic and in silico RFLP analysis of partial 16S rRNA and secA gene sequences of eight strains of sugarcane grassy shoot phytoplasma representative of the eight states confirmed the association of ‘Candidatus phytoplasma oryzae’-related strains (16SrXI-B) with symptomatic sugarcane varieties. The study confirmed that secA gene-specific primers could be employed for molecular characterization of phytoplasmas associated with sugarcane grassy shoot phytoplasmas belonging to 16SrXI group.

OPTIMIZATION OF SOLID-LIQUID EXTRACTION WITH THE LOW TEMPERATURE PARTITION FOR THE DETERMINATION OF CARBOFURAN IN SUGAR CANE

The broad application of cabofuran pesticide in sugar-cane cultures and its high toxicity makes it essential a search for new methods of preparing the samples to analysis of this pesticide in this culture. This work tried to optimize the solid-liquid extraction technique with low temperature partitioning (SLE/LTP) to determine the carbofuran in samples of sugar cane. The SLE/LTP technique, is a simple technique that shows advantages regarding other extraction techniques. Being so, a factorial experimental design 23 was created to study the simultaneous behavior of three factors in two levels. After this stage of split, to split, identification and qualification of carbofuran was analyzed the supernatant using the high efficiency of liquid chromatography with ultraviolet detector (HPLC/UV). The method ´s efficient to the extraction of carbofuran from sugar cane with percentages of recovery over the 73,0 %. After optimizing, the technique was applied in real samples of sugar cane in the region of Itumbiara-GO, Brazil. No carbofuran residues were found in the analyzed samples or they were below the detection limit. The SLE/LTP technique optimized to sugar cane, showed to be simple and efficient, being a economic method, consuming a little amount of sample and solvent extractor.

Occurrence of a novel mastrevirus in sugarcane germplasm collections in Florida, Guadeloupe and R\xe9union

BackgroundIn Africa and Asia, sugarcane is the host of at least seven different virus species in the genus Mastrevirus of the family Geminiviridae. However, with the exception of Sugarcane white streak virus in Barbados, no other sugarcane-infecting mastrevirus has been reported in the New World. Conservation and exchange of sugarcane germplasm using stalk cuttings facilitates the spread of sugarcane-infecting viruses.MethodsA virion-associated nucleic acids (VANA)-based metagenomics approach was used to detect mastrevirus sequences in 717 sugarcane samples from Florida (USA), Guadeloupe (French West Indies), and Réunion (Mascarene Islands). Contig assembly was performed using CAP3 and sequence searches using BLASTn and BLASTx. Mastrevirus full genomes were enriched from total DNA by rolling circle amplification, cloned and sequenced. Nucleotide and amino acid sequence identities were determined using SDT v1.2. Phylogenetic analyses were conducted using MEGA6 and PHYML3.ResultsWe identified a new sugarcane-infecting mastrevirus in six plants sampled from germplasm collections in Florida and Guadeloupe. Full genome sequences were determined and analyzed for three virus isolates from Florida, and three from Guadeloupe. These six genomes share >88% genome-wide pairwise identity with one another and between 89 and 97% identity with a recently identified mastrevirus (KR150789) from a sugarcane plant sampled in China. Sequences similar to these were also identified in sugarcane plants in Réunion.ConclusionsAs these virus isolates share <64% genome-wide identity with all other known mastreviruses, we propose classifying them within a new mastrevirus species named Sugarcane striate virus. This is the first report of sugarcane striate virus (SCStV) in the Western Hemisphere, a virus that most likely originated in Asia. The distribution, vector, and impact of SCStV on sugarcane production remains to be determined.