Potential of a novel antibiotic, 2-methylheptyl isonicotinate, as a biocontrol agent against fusarial wilt of crucifers

Screening for newer bioactive compounds from microbial metabolites resulted in the isolation of a novel antibiotic from the culture filtrate, Streptomyces sp 201, of a soil. The bioactive compound, with antifungal and antibacterial activity, was identified as 2-methylheptyl isonicotinate. The antifungal activity of live culture, culture broth and the isolated bioactive compound showed marked inhibition against dominant soil-borne phytopathogens such as Fusarium oxysporum Schlect, F moniliforme Sheldon, F semitectum Berkeley & Ravenel, F solani (Martius) Sacc and Rhizoctonia solani Kuehn. The compound had no effect on seed germination and seedling development as displayed by root and stem growth of the test plant species. In pot experiments with seedlings of cruciferous plants such as Raphanus sativus L (radish), Brassica campestris L (yellow mustard), Brassica oleracea var botrytis L (cauliflower), the antibiotic compound showed promising protective activity of 92% when seeds of the test plants were treated at a dose of 50 micrograms ml-1 prior to sowing. Seed treatment with a spore suspension (3 x 10(8) spores ml-1) of the Streptomyces sp 201 displayed protective activity in the range of 56-60%. Seeds coated with 2.5% methyl cellulose-amended spores of the antagonist showed protective activity in the range of 64-72%. Further, seed treatment with the culture filtrate of the antagonist also showed promising protective activity in the range of 64-84%.     

In vitro plantlet regeneration from protocorms of Dendrobium lituiflorum Lindl. and Cymbidium bicolor Lindl. and their acclimatisation: effect of salts,sucrose, and banana extract

Summary

The salts present in modified Knudson C (KC) medium (1946), 2% (w/v) sucrose, and a natural banana extract (BE) [1 – 20% (v/v)] were studied singly, or in combination, for their effects on the regeneration of protocorms of the orchid species, Dendrobium lituiflorum and Cymbidium bicolor. The incorporation of KC salts along with higher percentages of BE [10% or 20% (v/v)] promoted protocorm development as well as shoot and root formation. The presence of 2% (w/v) sucrose in the medium further enhanced root lengths and the rooting percentage, irrespective of the presence of KC salts. Incorporation of both KC salts and 2% (w/v) sucrose was found to be obligatory, in conjunction with BE (a cost-effective natural additive) for plantlet regeneration. In vitro-raised plantlets of both orchid species exhibited high rates of survival under greenhouse conditions. Scanning electron microscopy revealed elliptical stomata and epicuticular granular wax deposits on their abaxial leaf surfaces after acclimatisation.     

Chemical genomic profiling for antimalarial therapies, response signatures, and molecular targets

Malaria remains a devastating disease largely because of widespread drug resistance. New drugs and a better understanding of the mechanisms of drug action and resistance are essential for fulfilling the promise of eradicating malaria. Using high-throughput chemical screening and genome-wide association analysis, we identified 32 highly active compounds and genetic loci associated with differential chemical phenotypes (DCPs), defined as greater than or equal to fivefold differences in half-maximum inhibitor concentration (IC(50)) between parasite lines. Chromosomal loci associated with 49 DCPs were confirmed by linkage analysis and tests of genetically modified parasites, including three genes that were linked to 96% of the DCPs. Drugs whose responses mapped to wild-type or mutant pfcrt alleles were tested in combination in vitro and in vivo, which yielded promising new leads for antimalarial treatments.     

Classification of yarn interlacement pattern in fabrics using least square support vector machines

The purpose of this paper is to suggest an effective and reliable tool that can read through fabric images in the quest of deciphering yarn interlacement patterns by means of Least-Square Support Vector Machines (LS-SVM). A LS-SVM based binary pattern recognition system is formulated for identifying two modes of yarn interlacements viz., warp over weft or warp under weft and accuracy of the classifier was assessed by k-fold cross validation techniques. A comparative study establishes that LS-SVM shows better result than the standard SVM while classifying yarn interlacement patterns in fabrics. The proposed method has the potential to classify yarn interlacement patterns with possibility of extending it to designdecoding of diverse fabrics.     

Hydrothermal and biotechnological treatments on nutraceutical content and antioxidant activity of rice bran

The effect of processing such as steaming, germination and parboiling on nutraceuticals and in vitro bioactive properties of rice bran from three different rice varieties namely Jyothi (pigmented), IR64 and Sona masuri (non-pigmented) were investigated. Within the varieties envisaged, pigmented Jyothi variety contained higher levels of vitamin E, soluble, bound and total polyphenol, flavanoids, free radical scavenging activity and total antioxidant activity. Direct steam exposure of bran resulted in an increase in, ether extractives and oryzanol, as well as retention of all the vitamin E components, bound polyphenols, flavonoids and decrease in soluble and total polyphenol content, free radical scavenging activity and total antioxidant activity compared to native. Parboiling as well as germination of paddy resulted in an increase, in the content of ether extractives and oryzanol, whereas other bioactive properties decreased compared to native. Hence it may be concluded that bioactive components and antioxidant properties were significantly higher in Jyothi bran compared to the other two paddy brans, and processing leads to changes in bioactive properties with maximum retention of bioactive components in the steamed bran.     

The dynamics of Phytophthora infestans populations in the major potato-growing regions of Asia – A review

Asia is now the largest potato-producing region of the world and late blight, caused by Phytophthora infestans, is the most important pathogen limiting production. This review documents, in both the historical and the current context, the population structure of P. infestans in the major areas of potato production in Asia. Information from diverse sources regarding the stated or inferred clonal pathogen lineages present, population changes, and possible migration routes of the pathogen into the countries of this region have been reviewed to aid researchers and those involved in managing late blight in Asia. The single most important factor for population change and resultant epidemics in this region has been found to be migration of pathogen genotypes from Europe and the Americas. Reducing the impact of such migration in the future will necessitate putting in place improved phytosanitary measures. To achieve this, data sharing using global networks such as AsiaBlight and EuroBlight is imperative.     

Vegetative propagation of <Emphasis Type="Italic">Holarrhena pubescens</Emphasis>, a wild tropical medicinal plant: effect of indole-3-butyric acid (IBA) on stem cuttings

The present study investigated the rooting ability and growth performance of juvenile single-node leafy stem cuttings of     

Vegetative propagation and initial growth performance of <Emphasis Type="Italic">Stereospermum suaveolens</Emphasis> DC., a wild tropical tree species of medicinal value

The present study aimed at examining the amenability of Stereospermum suaveolens DC. to vegetative propagation through rooting of leafy stem cuttings using low-cost polythene propagators. Rooting efficiencies of cuttings derived from two selected matured mother trees were studied using four different concentrations of Indole-3-butyric acid (IBA), viz. 0, 0.1, 0.2 and 0.4%. IBA applied at 40 μg per cutting (0.4% concentration) resulted in significantly higher rooting responses compared to the control (P < 0.05). Differences in the length of longest root for all the treatments were significant (P = 0.05) with cuttings treated with 0.2% IBA producing the longest root. The highest survival after 3 weeks of transference of the rooted cuttings into polythene bags was found for rooted cuttings treated with 0.2% IBA. Effects of three fertilizer treatments viz. T₀ (no fertilizer), T₁ (10 g of Urea + 20 g of TSP + 10 g of MOP dissolved in 1 l of water) and T₂ (10 g of Urea + 20 g of TSP + 10 g of MOP dissolved in 2 l of water) on initial growth of established rooted cuttings (stecklings) of Stereospermum suaveolens in polythene bags were also measured for a period of 90 days. Stem length, collar diameter and leaf area of the stecklings increased throughout the observation period. Increments of both stem length and collar diameter were significantly higher for the stecklings treated with T₂ in comparison with the control while increment of leaf area was found the highest for the stecklings treated with T₁. The study clearly indicated that Stereospermum suaveolens is amenable to vegetative propagation technique using juvenile single-node leafy cuttings and the initial growth performance of the established rooted cuttings (stecklings) in polythene bags under different fertilizer treatments was satisfactory.     

Transforming fusions of FGFR and TACC genes in human glioblastoma

The brain tumor glioblastoma multiforme (GBM) is among the most lethal forms of human cancer. Here, we report that a small subset of GBMs (3.1%; 3 of 97 tumors examined) harbors oncogenic chromosomal translocations that fuse in-frame the tyrosine kinase coding domains of fibroblast growth factor receptor (FGFR) genes (FGFR1 or FGFR3) to the transforming acidic coiled-coil (TACC) coding domains of TACC1 or TACC3, respectively. The FGFR-TACC fusion protein displays oncogenic activity when introduced into astrocytes or stereotactically transduced in the mouse brain. The fusion protein, which localizes to mitotic spindle poles, has constitutive kinase activity and induces mitotic and chromosomal segregation defects and triggers aneuploidy. Inhibition of FGFR kinase corrects the aneuploidy, and oral administration of an FGFR inhibitor prolongs survival of mice harboring intracranial FGFR3-TACC3-initiated glioma. FGFR-TACC fusions could potentially identify a subset of GBM patients who would benefit from targeted FGFR kinase inhibition.     

<Emphasis Type="Italic">Mangifera sylvatica</Emphasis> Roxb. in the Forests of South-Eastern Bangladesh: A Potential Underutilised Tree for Small-Scale Forestry

Mangifera sylvatica Roxb. is an underutilized wild tree species valued for its fruit, timber and medicine. It was believed to be widely grown in sub-tropical forests of Bangladesh, but nowadays can be seen only sparsely. Even though it has multiple uses, only the indigenous people in hilly areas use the fruit of this species, for cooking and making pickles. This study was designed to (1) observe the population status of M. sylvatica in the forests of south-eastern Bangladesh, (2) evaluate domestication potentiality through seed germination and early growth of seedlings, and (3) assess its suitability for small-scale forestry. Through 16 field visits in eight forest beats, 66 individual trees were identified and their GPS (global positioning system) coordinates were recorded. A seed germination rate of 83 % at 6 weeks after direct sowing was attained. The early growth of seedlings with fertilizer treatments showed no remarkable difference with seedlings without fertilization. The seed germination rate and early growth of seedlings indicates that this species can be easily domesticated and be incorporated into small-scale plantation programs. In that it has multiple use values, this species warrants promotion in small-scale forestry programs for conservation and benefiting the villagers.