New species of Phaeoramularia, Pseudocercospora and Stenella from Western Ghats of India

Four new species of the hyphomycete genera Phaeoramularia viz. Ph. caesalpinae, Pseudocercospora viz., Ps. tiliacearum, Stenella, viz. S. argyreiae and S. grewiae occurring on Caesalpinia bonducella Fleming (Caesalpiniaceae), Grewia sp. (Tiliaceae), Argyrea sp. Lour (Convolvulaceae) and Grewia sp. L. (Tiliaceae), respectively are described and illustrated here. All these fungi were collected from Western Ghats of India.     

The moss genus Leptobryum and the identity of Pohlia integra

Abstract

Leptobryum Wilson (Bryaceae) consists of two species, viz., Leptobryum pyriforme (Hedw.) Wilson and L. wilsonii (Mitt.) Broth. Pohlia integra (Cardot) A.J.Shaw and three other species of Leptobryum, viz., L. escomelii Thér., L. pottiaceum Dusén, L. stellatum (Herzog) Broth. are reduced to synonomy under L. wilsonii. L. sericeum Kindb. is considered a doubtful species because no specimen could be located.     

Genetic and Pathogenic Variability of Indian Strains of <Emphasis Type="Italic">Xanthomonas campestris</Emphasis> pv. <Emphasis Type="Italic">campestris</Emphasis> Causing Black Rot Disease in Crucifers

Xanthomonas campestris pv. campestris (Pammel) Dowson (Xcc) causing black rot of crucifers is a serious disease in India and causes >50% crop losses in favorable environmental conditions. Pathogenic variability of Xcc, X. oryzae pv. oryzae (Xoo), and X. axonopodis pv. citri (Xac) were tested on 19 cultivars of cruciferae including seven Brassica spp. viz., B. campestris, B. carinata, B. juncea, B. napus, B. nigra, B. oleracea and B. rapa, and Raphanus sativus for two consecutive years viz., 2007–2008 and 2008–2009 under field conditions at Indian Agricultural Research Institute, New Delhi. Xcc (22 strains) and other species of Xanthomonas (2 strains), they formed three distinct groups of pathogenic variability i.e., Group 1, 2, and 3 under 50% minimum similarity coefficient. All strains of Xcc clustered under Groupl except Xcc-C20. The strains of Xcc further clustered in 6 subgroups viz., A, B, C, D, E, and F based on diseases reaction on host. Genetic variability of 22 strains of Xcc was studied by using Rep-PCR (REP-, BOX- and ERIC-PCR) and 10 strains for hrp (hypersensitive reaction and pathogenecity) gene sequence analysis. Xcc strains comprised in cluster 1, Xac under cluster 2, while Xoo formed separate cluster 3 based on >50% similarity coefficient. Cluster 1 was further divided into 8 subgroups viz., A, B, C, D, E, F, G, and H at 75% similarity coefficient. The hrpF gene sequence analysis also showed distinctness of Xcc strains from other Xanthomonads. In this study, genetic and pathogenic variability in Indian strains of Xcc were established, which will be of immense use in the development of resistant genotypes against this bacterial pathogen.     

Endogenous polyamine profiles in different tissues of <Emphasis Type="Italic">Coffea</Emphasis> sp., and their levels during the ontogeny of fruits

Polyamines are essential compounds for growth and development in plants. An attempt has been made to find out the endogenous polyamine profiles in various parts and during the ontogeny of fruit formation of two commercially important Coffea species viz., arabica and canephora. Putrescine (Put), spermine (Spm) and spermidine (Spd) are the predominant polyamines during the ontogeny of fruit and their level increased with the advancement of fruit development. However, in the initial stages of flower and fruit development Spm levels were found to be decreased. Elevated levels of major polyamines Put, Spd, and Spm were observed in zygotic embryos than in somatic embryos. Along with this cadavarine (Cad) and other biogenic amines viz., tyramine (Tyr) and tryptamine (Try) were also found during the ontogeny of fruit in C. canephora. In this study the enodogenous polyamine profiles in coffee tissues and beans have been addressed.     

Phytochemical analysis and antimicrobial activity of Cardaria draba (L.) Desv. volatiles

Two different volatile isolates from the aerial parts of Cardaria draba (L.) Desv., obtained either by hydrodistillation (Extract I) or by CH₂Cl₂ extraction subsequent to hydrolysis by exogenous myrosinase (Extract II), were characterized by GC‐FID and GC/MS analyses. The main volatiles obtained by hydrodistillation, i.e., 4‐(methylsulfanyl)butyl isothiocyanate ( 1 ; 28.0%) and 5‐(methylsulfanyl)pentanenitrile ( 2 ; 13.8%), originated from the degradation of glucoerucin. In Extract I, also volatiles without sulfur and/or nitrogen were identified. These were mostly hexadecanoic acid (10.8%), phytol (10.2%), dibutyl phthalate (4.5%), and some other compounds in smaller percentages. Extract II contained mostly glucosinolate degradation products. They originated from glucoraphanin, viz., 4‐(methylsulfinyl)butyl isothiocyanate ( 3 ; 69.2%) and 5‐(methylsulfinyl)pentanenitrile ( 4 ; 4.5%), glucosinalbin, viz., 2‐(4‐hydroxyphenyl)acetonitrile ( 5 ; 7.2%), and glucoerysolin, viz., 4‐(methylsulfonyl)butyl isothiocyanate ( 6 ; 5.0%). Moreover, the volatile samples were evaluated for their antimicrobial activity using the disc‐diffusion method and determining minimum inhibitory concentrations (MIC). All volatile isolates expressed a wide range of growth inhibition activity against both Gram‐positive and Gram‐negative bacteria and fungi. The MIC values varied between 4 and 128 μg/ml.     

Antifungal activity of the mixture of quaternary alkaloids isolated from Argemone mexicana against some phytopathogenic fungi

The anti-fungal activity of a mixture of quaternary alkaloids of Argemone mexicana was observed at different concentrations (1000, 2000, 3000, 4000 and 5000 μl/ml) against 10 fungi, viz., Ustilago cynodontis, Cercospora cajani, Sphaerotheca sp., Cercospora sp., Alternaria solani, Bipolaris sp., Helminthosporium sp., Curvularia sp., Fusarium udum and Alternaria cajani. Spore germination was inhibited at 2000, 3000, 4000, 5000 μg/ml. Analysis of phenolics by high performance liquid chromatography (HPLC) recorded 11 peaks in the alkaloids but only three could be identified, viz., tannic, caffeic and ferulic acids. The significant efficacy of the alkaloid under in vitro conditions may open the possibility of its use by farmers under field conditions for controlling some crop diseases.     

Comparative analysis of the differential regeneration response of various genotypes of <Emphasis Type="Italic">Triticum aestivum</Emphasis>, <Emphasis Type="Italic">Triticum durum</Emphasis> and <Emphasis Type="Italic">Triticum dicoccum</Emphasis>

An efficient genotype independent, in vitro regeneration system was developed for nine popular Indian wheat cultivars, three each of Triticum aestivum L. viz., CPAN1676, HD2329 and PBW343, Triticum durum Desf. viz., PDW215, PDW233 and WH896, and Triticum dicoccum Schrank. Schubl. viz., DDK1001, DDK1025 and DDK1029, by manipulating the concentration and time of exposure to the growth regulator, thidiazuron (TDZ). A total of 18 (for immature inflorescence and embryo explant) and six (for mature embryo explant) different combinations of growth regulators were tried for callusing and regeneration, respectively. Media combination with low concentration of TDZ (2.2 μM) in combination to auxin and/or cytokinin (depending upon culture stage), was found to be effective for immature and mature explants. Compact, nodular and highly embryogenic calli were obtained by using immature embryo, immature inflorescence and mature embryo explants, and regeneration frequency up to 25 shoots/explant with an overall 80% regeneration was achieved. Comparable regeneration frequency was achieved for mature embryo explants. No separate hormone combination for rooting was required and plantlets ready to transfer to soil could be obtained in a short period of 8–10 weeks. This protocol can be used for raising transgenic plants for functional genomics analysis of agronomically important traits in the three species of wheat.     

A study by cryo-scanning electron microscopy of the initiation and early development of an inflorescence in glasshouse celery (Apium graveolens L. var. dulce (Miller) Pers.) grown under inductive conditions

The morphology of flower initiation and early development in glasshouse celery (Apium graveolens L. var. dulce (Miller) Pers.) cv. Celebrity was studied by means of apical dissections and cryo-scanning electron microscopy. Easily recognisable morphological features were used to define seven stages in the early development of the inflorescence. A highly significant linear regression was established between the logarithm of the apical diameter (measured diametrically across the apical dome between the two most recently initiated leaf or inflorescence primordia) and these discrete floral stages. There was no strong evidence that either the origin or the slope of the regression varied with different combinations of temperature (viz. 10°C or 14°C) and daylength (viz. natural, short or long) which were conducive for the initiation and development of an inflorescence. It is suggested that both apical diameter and floral stage may be used as parameters for assessing the influence of environmental factors such as temperature and daylength on the floral development of glasshouse celery.     

Chitinolytic microbes confer Meloidogyne incognita resistance and augment secondary metabolites in Bacopa monnieri (L.) Pennell

Meloidogyne incognita (Kofoid and White) Chitwood a calamitous plant pathogen affects almost all the commercial crops, especially medicinal plants viz. Bacopa monnieri L. In this study, the efficacy of indigenous chitinolytic microbes against M. incognita in B. monnieri was evaluated under sterilised and natural soil conditions. The plant growth was observed for various parameters viz. nutrient uptake, phytochemical activities and secondary metabolites (bacoside). In the natural soil under green house conditions, the isolates significantly (P ≤ 0.05) reduced M. incognita infestation (1.38–2.78-folds) with significant increase in secondary metabolites (1.28–1.88-fold) over the untreated control. The potential strains were identified through 16S-rRNA as Streptomyces sp., Microbacterium arabinogalactanolyticum, Cellulosimicrobium cellulans, Actinomycetales bacterium, Chitiniphilus sp. and Flavobacterium johnsoniae. These findings thus highlight the potential of indigenous chitinolytic microbes that can be utilised for overall fitness of the plant along with the reduced root-knot nematode infestation in B. monnieri.     

Interesting taxa ofStaurastrum Meyen (Desmidiaceae) from Karnataka State (India)

Algae were collected from a paddy field at Belgaum during August 1985. Two new taxa ofStaurastrum Meyen (viz.S. quebecense Irénée-Marie fa.minor Bongale fa.nov. andS. sebaldii Renisch var.triangularis Bongale var. nov.) and two other taxa showing major variations (viz.S. gracile Ralfs. var.elongatulum West et West fa. andS. leutkemuelleri Donat et Ruttner ms. fa.) are reported.     

Reversed-phase liquid chromatographic resolution of diastereomers of protein and non-protein amino acids prepared with newly synthesized chiral derivatizing reagents based on cyanuric chloride

Two new chiral monochloro-s-triazines (MCT) were synthesized [viz N-(4-chloro-6-piperidinyl-[1,3,5]-triazine-2-yl)-l-leucine amide and N-(4-chloro-6-piperidinyl-[1,3,5]-triazine-2-yl)-l-leucine) (CDR 1 and 2, respectively)] by the nucleophilic displacement of chlorine atoms in s-triazine moiety. One of the Cl atoms was replaced with piperidine, and the second Cl atom in the 6-piperidinyl derivative was replaced with amino acid amide (viz l-Leu–NH₂) and amino acid (l-Leu). These reagents were characterized and used as CDRs for chiral separation of protein and non-protein amino acids, and were separated on a reversed-phase C₁₈ column. The reaction conditions were optimized for the synthesis of diastereomers using one MCT reagent. The separation method was validated for limit of detection, linearity, accuracy, precision, and recovery.     

Molecular characterization of Jatropha genetic resources through inter-simple sequence repeat (ISSR) markers

The genetic diversity among eight Jatropha species and three Jatropha curcas accessions were analyzed using ISSR-PCR. Nine ISSR primers generated reproducible amplification banding pattern of 61 polymorphic bands out of 64 scored accounting for 98.14% polymorphism across the species. The ISSR primers viz., I1, I2, I3, I4, I5, I6, I7 and I10 generated 100% polymorphic patterns. Jaccard’s coefficient of similarity varied from 0.346 to 0.807, indicative of high level of genetic variation among the genotypes studied. The UPGMA cluster analysis indicated three distinct clusters, one comprising all accessions of J. curcas L (TNMJ1, TNMJ 22 and TNMJ 23), while second included four species viz., J. tanjorensis J. L. Ellis et Saroja., J. gossypifolia L., J. podagrica Hook and J. maheshwarii Subrum and M.P. Nayer and the third cluster included another four species viz., J. villosa Wight J. multifida L., J. integerrima Jacq and J. glandulifera Roxb. The overall grouping pattern of clustering corresponds well with principal component analysis (PCA) confirming patterns of genetic diversity observed among the species. So far, there are no reports on the molecular diversity of the Jatropha species through ISSR marker. This study provides valid guidelines for collection, conservation and characterization of Jatropha genetic resources and also for further breeding programme towards biodiesel production.     

Molecular characterization of eight Indian Snakehead species (Pisces: Perciformes Channidae) using RAPD markers

Murrels (Perciformes; Channidei; Channidae) are unique group of freshwater air breathing fishes having a confined distribution to African and Asian continents. The phylogenetic relationship among eight Channid species viz. Channa aurantimaculata, Channa bleheri, Channa diplogramma, Channa gachua, Channa marulius, Channa punctatus, Channa stewartii and Channa striatus were investigated using RAPD markers. Eight random oligodecamers viz. OPAC03, OPAC05, OPAC07, OPAC09, OPAC19, OPA10, OPA11 and OPA16 were used to generate the RAPD profile. Estimates of Nei’s (Genetics, 89:583–590, 1978) unbiased genetic distance (D) demonstrated sufficient genetic divergence to discriminate the samples of different species and the values ranged from 0.3292 to 0.800 The present RAPD analyses strongly substantiate the view of earlier morphological and osteological studies of Channid species, the closer association among species in “gachua” and “marulius” groups.     

Arbuscular mycorrhizal status and root phosphatase activities in vegetative <Emphasis Type="Italic">Carica papaya</Emphasis> L. varieties

The arbuscular mycorrhizal (AM) status and root phosphatase activities were studied in four vegetative Carica papaya L. varieties viz., CO-1, CO-2, Honey Dew and Washington. Standard techniques were used to ascertain information on spore density and species diversity of AM fungi. Although in case of estimation of root colonization and root phosphatase activities, the existing methods were slightly modified. Root colonization and spore density of AM fungi along with root phosphatase (acid and alkaline) activities varied significantly in four papaya varieties. The present study recorded higher acid root phosphatase activity when compared with alkaline root phosphatase activity under P-deficient, acidic soil conditions. The present study revealed that the root colonization of AM fungi influenced acid root phosphatase activity positively and significantly under P-deficient, acidic soil conditions. A total of 11 species of AM fungi belonging to five genera viz., Acaulospora, Dentiscutata, Gigaspora, Glomus and Racocetra were recovered from the rhizosphere of four papaya varieties.     

Epiphytic microflora of poplar clones susceptible and resistant to infection by Dothichiza populea

One-year-old poplar shoots (nodes, internodes and lenticels) of clones susceptible to infection by the pathogenic fungus Dothichiza populea, viz. Populus nigra Italica and P. Robusta, resistant ones, viz. P. Grandis and P. Hybrida 275, as well as a hybrid of a susceptible and a resistant clone, viz. P. maximowiczii x P. nigra (P. Kórnik 42), were used. The plate method was employed to determine: 1. the abundance of the epiphytic microflora on a mineral medium with glucose; 2. the quantitative composition of epiphytic communities by determining the numbers of typical bacteria (including rod-shaped, spherical and sporulating forms), actinomycetes and yeasts in microscopic preparations from epiphyte colonies; 3. the abundance and level of activity of epiphytes antagonistic towards Dothichiza populea. In all poplar clones the epiphytic microflora was most abundant on nodes and least abundant on lenticels. In the resistant clones epiphytes were 7 (P. Grandis) to as many as 84 times (P. Hybrida 275) less numerous than in the susceptible ones. In the microflora communities of the susceptible poplars, rod-shaped bacteria were the most abundant, and in the resistant ones and the hybrid, yeasts, which made up from 60% to 70% of the strains tested. Spherical and sporulating bacteria as well as actinomycetes were found in numbers not exceeding 4% of the total number of epiphytes. The proportion of antagonistic microflora in whole epiphytic communities was higher in the resistant clones and the hybrid than in the susceptible clones, with the microflora having a more restrictive effect on the development of the pathogen.     

Biological spectrum of Trichoderma harzianum Rifai isolates to control fungal diseases of tomato (Solanum lycopersicon L.)

Three Trichoderma harzianum isolates viz., Th-Sks, Th-Ke and Th-Ar collected from respective states of India viz., Rajasthan, Kerala and Andhra Pradesh were evaluated for the management of six fungal diseases namely damping off, Fusarium wilt, Rhizoctonia wilt, early leaf spot, late blight and Septoria leaf spot in tomato. During in vitro analysis, T. harzianum isolates inhibited the pathogens’ growth. Isolate Th-Sks was the most virulent antagonist against all the test pathogens and exhibited maximum of 79.47% growth inhibition of Phytophthora infestans. Isolate Th-Sks proved most effective at suppression efficacy in the range of 95–100% and 91–100% against all diseases under glasshouse and in the field conditions, respectively. Tomato seeds treatment with isolate Th-Sks also promoted plant height (78.23 cm) and fruits yield (290 g/plant) during field trial and data were found to be not-significantly different from other isolates. Thus, it is concluded that isolate Th-Sks can be utilised as a biocontrol agent for management of fungal diseases in tomato.     

Fungi parasitising the eggs of certain fresh water fishes

By the present investigations the parasitic abilities of five isolates of Saprolegniaceous fungi have been established on the eggs of three fresh water fishesviz., Channa marulius Ham.,Channa gachua Ham., andNotoptenis notopterus Ham. These fungi areAchlya orion CokerAchlya prolifera (Nees) De Bary,Aphanomyces laevis Minden andSaprolegnia ferax (Gruith) Thuret.     

Antioxidant Peptides from the Protein Hydrolysates of <Emphasis Type="Italic">Conus betulinus</Emphasis>

The current study aims at the isolation and characterization of the peptides, believed to have antioxidant activity, from Conus betulinus by using different types of enzymes. The body and viscera of C. betulinus were treated with three enzymes viz. trypsin, pepsin and papain to obtain peptide hydrolysates. The activities of the hydrolysates were analyzed by DPPH and hydroxyl radical assay by using electron spin resonance (ESR) device. Active hydrolysates were purified using ion exchange chromatography followed by gel filtration chromatography. The activity of the separated fractions was analyzed by ESR; in which the result showed that trypsin hydrolysate of body (28.48 and 76.00%) and viscera (38.45 and 83.00%) respectively have high activity than the other hydrolysates. The HPLC result of purified fraction showed, presence of active amino acids viz., metheonine, cystine, histidine etc. This purified peptide has more antioxidant activity that could reduce the excess free radicals in body in order to prevent free radical induced diseases.     

Production of antibacterials from the freshwater alga Euglena viridis (Ehren)

The antibacterial properties of Euglena viridis, collected from a freshwater pond at the Central Institute of Freshwater Aquaculture (CIFA), Bhubaneshwar, India, were tested against various strains of virulent pathogens viz. Pseudomonas putida(PP1, PP2),P. aeruginosa (PA1, PA2, PA3, PA4), P. fluorescens (PF1, PF2, PF3, PF4), Aeromonas hydrophila (AH30, AH31, AH32, AH34), Edwardsiella tarda, Vibrio alginolyticus (VA1),V. anguillarum(VN1, VN2 & VN3), V. fluvialis (VF1), V. parahemolyticus (VP1) and V. harveyi (VH1) andEscherichia coli(O115, O1, O156, O164, O111 & O109). Four organic extracts viz. methanolic, ethanolic, acetone and acetone/ethanol of theE. viridis showed moderate to high antibacterial activity to all the bacterial pathogens. Rotavapor extraction products showed higher sensitivity in comparison to cold and hot extractions.