Molecular basis of resistance in wheat varieties against spot blotch disease

During present investigation, among the six wheat genotypes tested against six isolates of Bipolaris sorokiniana, the genotype BOW‘S’ showed resistance response against three isolates, namely, BS-D-1, BS-DWRK-2 and BS-K-4, whereas moderately resistance response against remaining 3 isolates i.e. BS-F-3, BS-P-5 and BS-V-6.The genotype A-9-30-1 showed almost highly susceptible response against each isolate except BS-D-1 which exhibited susceptible reaction on this genotype. Thus, it is clear that genotype BOW ‘S’ has broad genetic base for resistance, whereas genotype A-9-30-1 has no gene for resistance against these six isolates tested. Remaining five genotypes showed varying response, ranging from highly susceptible, susceptible, moderately susceptible, moderately resistant and resistant against various isolates of B. sorokiniana tested

Integrated nutrient management to enhance biochemical resistance in rice against sheath blight

Application of potassium either as recommended, deficient or excess dose, enhanced the level of phenolic contents, increased incubation period and thereby decreased the sheath blight severity. Application of nitrogen and phosphorous, either as recommended, deficient or excess dose resulted in reduction of phenolic content, shorter incubation period and thereby increasing the sheath blight severity. Recommended sulphur application, enhanced the phenolic contents, increased incubation period and thereby decreased the sheath blight severity. Recommended zinc application resulted in enhancement of phenolic contents, longer incubation period and thereby decreasing the sheath blight severity. Excess application of zinc, reduced the phenolic contents and incubation period but the severity of sheath blight was also lowered down. Recommended iron application (1.5 kg./ha) enhanced the phenolic contents and incubation period with a decreased level of sheath blight severity. Deficient and excess doses of iron also showed the similar trend of effect on phenolics, incubation period and sheath blight severity

F-wave records with submaximal stimulation: sustainability of the data and subject discomfort levels

Background: F-wave studies are valuable electrodiagnostic tests with considerable roles in early diagnosis of diabetic neuropathy, detection of axonal neuropathies and focal proximal nerve dysfunctions. The recording of F-waves, however, requires recurrent supramaximal stimulation which entails subjects’ discomfort during the procedure. The present study hence attempted to assess the validity of the F-wave data obtained after submaximal stimulation thereby lessening the subject discomfort levels.Methods: The study was conducted on 64 healthy subjects in the age-group of 18-40 years with normal neurological examinations. F responses from median, ulnar, tibial and peroneal nerves by both supramaximal and submaximal stimulation were recorded. Subjects rated discomfort level on a visual analogue scale. Mean values of F-wave minimum latency, mean latency, mean duration, persistence, chronodispersion, F/M amplitude ratio and subject’s discomfort level obtained by the two techniques were compared by paired t-test. P value 0.05). Mean persistence, mean F/M amplitude ratio and mean subject discomfort levels varied statistically significantly.Conclusions: F-wave data can be attained by submaximal stimulation. F-wave mean and minimum latency, chronodispersion and duration remain relatively stable, but more stimuli may be needed for accurate values. For F/M amplitude ratio and F-wave persistence, submaximal reference range would be required. Nonetheless, diminution in subject discomfort with valid F-wave latency values, favours low intensity stimulation

Management of sheath blight in rice through application of Validamycin, Trichoderma harzianum and Pseudomonas fluorescence

Eleven different combinations of Trichoderma harzianum, Psedumonas fluorescens and Validamycin 3L, were applied at different crop stages viz. seed, seedling, tillering and symptoms initiation along with one application of Carbendazim as standard control to test their efficacy against sheath blight of rice caused by Rhizoctonia solani under field condition. One application of Carbendazim @ 0.1% at the time of symptoms initiation (with 81.36 percent reduction of disease incidence, 83.17 percent reduction in disease severity and 62.92 percent inhancement in yield) and seed treatment with Trichoderma harzianum and seedling root dipping with Pseudomonas fluorescens and two spraying of Validamycin i.e. at tillering and symptoms initiation stages (with 69.10 percent reduction of disease incidence,83.17 percent reduction in disease severity and 62.49 percent inhancement in yield) were found to be equally and highly effective in reducing the sheath blight severity and in increasing rice grain yield also. One spraying of Validamycin at symptoms initiation stage was comparatively less effective (29.54 per cent reduction in disease incidence,53.46 per cent reduction in disease severity and 47.76 per cent enhancement in yield ) than one spraying of Carbendazim at symptoms initiation stage

Genetic variability and relationship analysis of Bipolaris sorokiniana isolates causing spot blotch disease in wheat using random amplified polymorphic DNA (RAPD) markers

Twelve (12) isolates of Bipolaris sorokiniana (Cochliobolus sativus) of wheat were studied for their molecular characterization using random amplified polymorphic DNA (RAPD) techniques. Twenty (20) RAPD primers were tested for amplification of the genomic DNA of fungal isolates of wheat. A total of 77 bands were amplified, out of which 68 bands were polymorphic showing high range of variability (84.42% polymorphism) and nine bands were monomorphic. Average total number of bands generated per primer was 3.85, of which 3.4 and 0.45 were polymorphic and monomorphic, respectively. The genetic similarity coefficients for the 12 isolates of B. sorokiniana of wheat ranged from 0.526 to 0.842. The highest similarity occurred between DWR-Karnal versus Hisar-PBW-443 and Hisar-502 versus IARI with a coefficient value of 84.2% and the lowest similarity occurred between two fungal isolates that is, Hisar-WH-542 versus IARI and Meerut-Hallana versus Faizabad with a coefficient value of 52.6%. The study indicates that the RAPD is a good tool for determination of genetic variability and relationship of B. sorokiniana, which is already visible in the analysis of even such a small number of isolates.Keywords: Wheat, Bipolaris sorokiniana, genetic variability, polymorphism, random amplified polymorphic DNA (RAPD) markerAfrican Journal of Biotechnology Vol. 12(19), pp. 2526-253

Correlation of pattern reversal visual evoked potential parameters with the pattern standard deviation in primary open angle glaucoma

<b>AIM:</b>To evaluate whether glaucomatous visual field defect particularly the pattern standard deviation (PSD) of Humphrey visual field could be associated with visual evoked potential (VEP) parameters of patients having primary open angle glaucoma (POAG).<b>METHODS:</b>Visual field by Humphrey perimetry and simultaneous recordings of pattern reversal visual evoked potential (PRVEP) were assessed in 100 patients with POAG. The stimulus configuration for VEP recordings consisted of the transient pattern reversal method in which a black and white checker board pattern was generated (full field) and displayed on VEP monitor (colour 14”) by an electronic pattern regenerator inbuilt in an evoked potential recorder (RMS EMG EP MARK II).<b>RESULTS:</b>The results of our study indicate that there is a highly significant (<i>P</i>&lt;0.001) negative correlation of P100 amplitude and a statistically significant (<i>P</i>&lt;0.05) positive correlation of N70 latency, P100 latency and N155 latency with the PSD of Humphrey visual field in the subjects of POAG in various age groups as evaluated by Student’s <i>t</i>-test.<b>CONCLUSION:</b>Prolongation of VEP latencies were mirrored by a corresponding increase of PSD values. Conversely, as PSD increases the magnitude of VEP excursions were found to be diminished

Relationship of susceptibility and growth stages of plant for development of epidemic of sheath blight in rice

The present paper deals with most susceptible growth stage of rice with different farms and quantitiy of inoculum for development of sheath blight of rice by Rhizoctonia solani.Among seven different growth stages of rice crop i.e. seedling, initial tillering, maximum tillering, boot leaf, panicle emergence, flowering and dough stage, the flowering stage was found to be most susceptible and highly prone for sheath blight development, while seedling stage was found to be least susceptible and with low proneness for disease development. Disease severity, number and length of lesions get increased with the increasing crop growth stages up to flowering stage and thereafter disease severity decreases with the increases in further growth stages of rice plant. Among four different growth stages of the pathogen (inoculum capacity) i.e. five days old mycelium, seven days old mycelium, milky sclerotial stage and mature sclerotial stage which were inoculated at maximum tillering stage of rice plants, five days old mycelial inoculum was found to be most virulent. Disease severity decreased and incubation period increased with further ageing of inoculum. Among five different amount of inoculum (inoculum density) i.e. 0.20 mg, 5.50 mg, 6.00 mg, 7.00 mg and 8.00 mg of sclerotial inoculum, which were inoculated at maximum tillering stage of rice plants, highest disease severity and minimum incubation period was observed with 8.00 mg amount of sclerotial inoculum. Whereas, least disease severity and longest incubation period was observed when inoculation was done with 0.2 mg of sclerotial inoculum

Emission Characteristics of the Projectile Fragments at Relativistic Energy

A projectile (84^Kr_36) having kinetic energy around 1 A GeV was used to expose NIKFI BR-2 emulsion target. A total of 700 inelastic events are used in the present studies on projectile fragments. The emission angle of the projectile fragments are strongly affected by charge of the other projectile fragments emitted at same time with different emission angle is observed. The angular distribution studies show symmetrical nature for lighter charge projectile fragments. The symmetrical nature decreased with the charge of projectile fragments. At ~4o of emission angle for double charge projectile fragments, the momentum transfer during interaction is similar for various target species of emulsion were observed. We also observed a small but significant amplitude peaks on both side of the big peak for almost all light charge projectile fragments having different delta angle values. It reflects that there are few percent of projectile fragments that are coming from the decay of heavy projectile fragments or any other process.Comment: 32 pages, 17 Figure