MOSP - Macao Scientific Publishers

文章

Isolation and Identification of a Brevibacterium linens strain degrading p-nitrophenol

Debananda Ningthoujam

Abstract: A bacterium was isolated from garden soil in basal salts medium containing p-nitrophenol (PNP). Subsequent subcultures in basal salts agar, nutrient agar plates and agar slants by streaking led to isolation of pure colonies. The pure culture could degrade up to 300 mg/L PNP in presence of yeast extract. It was Gram positive rods, mostly single, catalase-positive, hydrolyzing strach and casein but not urea. Gelatin liquefaction was positive whereas acid production from carbohydrates was negative. It showed tyrosine clearing and had meso-DAP as the characteristic cell wall amino acid. On the basis of the morphological, physiological, and biochemical tests the organism was identified as Brevibacterium linens. To our knowledge, this is the first report of any Brevibacterium strain able to degrade PNP.[...] Read More.

Keywords: p-Nitrophenol, nitroaromatics, (bio) degradation, isolation, Brevibacterium.

Full text

Download：800

文章

Effect of cultural conditions on xylanase production by Streptomyces sp. (strain Ib 24D) and its potential to utilize tomato pomace

Rifaat Rawashdeh, Ismail Saadoun* and Amjad Mahasneh

Abstract: The purpose of this study was to determine the effect of some cultural conditions on the xylanase enzyme production by Streptomyces sp. (strain Ib 24D) and to investigate its potential to produce xylanase utilizing tomato pomace as a substrate. Xylanase activity was detected using the dinitrosalicylic acid assay method. The crude enzyme was maximally active at pH 6.5 and 60°C. The maximal enzyme production was obtained when oat spelt xylan was used as a carbon source. When tomato pomace was used as carbon and nitrogen source, the maximal xylanase production was 1447 U/ml. SDS-PAGE and zymogram analysis revealed one band of 58 kDa with xylanolytic activity. The Streptomyces sp . (strain Ib 24D) was able to produce a considerable amount of xylanase with high levels of activity at a broad ranges of pH and temperature, in addition to its ability to utilize tomato pomace as a carbon and a nitrogen source.[...] Read More.

Keywords: Agricultural wastes, biodegradation, Streptomyces sp., xylanase.

Full text

Download：814

文章

Quantitative trait loci for head-bug resistance in sorghum

M. Deu, A. Ratnadass*, M. A. Hamada, J.L. Noyer, M. Diabate† & J. Chantereau

Abstract: QTLs were mapped in F2 progeny derived from a cross between the head-bug resistant sorghum cultivar Malisor 84- 7 and susceptible S 34. The phenotypic evaluation was conducted in Mali. The mapped population consisted of 217 F2 plants, with 345 homologous and heterologous RFLP probes and 49 microsatellite markers tested. Eighty-one RFLP markers revealed polymorphism between the two parents, and 14 microsatellite markers gave usable amplification products. A genetic map including 92 loci distributed over 13 linkage groups, and covering a total distance of 1160 cM was built. Three significant and seven putative QTLs were detected and placed on the map.[...] Read More.

Keywords: Head-bug, Eurystylus oldi, sorghum, resistance, RFLP, microsatellite, QTL.

Full text

Download：762

文章

Somatic embryogenesis in date palm (Phoenix dactylifera L.) from apical meristem tissues from â€˜zebiaâ€™ and â€˜lokoâ€™ landraces

Somatic embryogenesis in date palm (Phoenix dactylifera L.) from apical meristem tissues from ‘zebia’ and ‘loko’ landraces

Abstract: The shoot apical meristem from young suckers were used as sources of explants for initiation of culture using MS basal medium which contained 2,4-D. This was incubated at 27oC in the dark. Callogenesis was observed as early as the second subculture. Continuous subculture of the callus in the establishment medium at about the third subculture from calls production, resulted in somatic embryo formation. The somatic embryos were then transferred to MS medium without hormones under light where they matured after about two subcultures and developed into shoots. The shoots produced roots when transferred to a medium which contained NAA at 0.1 mg/L.[...] Read More.

Keywords: somatic embryogenesis, date palm, in vitro, micropropagation.

Full text

Download：773

文章

Photoperiodism in Digitaria exilis (Kipp) Stapf accessions

A.A. Aliero and J.A. Morakinyo*

Abstract: Three varieties of Digitaria exilis namely, white mbulus, jakashale and red dapys were grown in planting chamber and the effect of photoperiod on flowering was investigated. The photoperiods were eleven, twelve and thirteen hours. Highly significant differences (p[...] Read More.

Keywords: Digitaria exilis, photoperiods, flowering.

Full text

Download：744

文章

Anther culture response in indica rice and variations in major agronomic characters among the androclones of a scented cultivar, Karnal local

Bidhan Roy, Asit B. Mandal*

Abstract: Effect of organic adjuvants, synthetic plant hormones and diverse carbon sources in influencing anther culture response in five indica rice genotypes (IR 72, Mansarovar, Taraori Basmati, Pusa Basmati and Karnal local 95) were assessed. Androgenic callus induction as well as green plantlet regeneration was more when callus was induced on N6 fortified with 100 mg L-1 YE. However, coconut water (5 and 10% concentrations from Pink Dwarf variety) encouraged green plantlet regeneration only in Karnal local 95. High callus induction was observed with synthetic hormones in comparison to the control set. However, green plantlet regeneration was observed when callus induction medium (CIM) was supplemented with 2, 4-D and IBA in Taraori Basmati and Karnal local 95. Among the varieties Pusa Basmati and Karnal local 95 showed better callus inductions on N6 supplemented with 6% maltose. Maximum callus induction was observed in Pusa Basmati and Karnal local 95 when 6% sucrose or maltose were used as carbon source. Total plantlet regeneration was cent percent in Taraori Basmati when CIM was supplemented with maltose (6%). Maximum green plants were obtained when CIM was added with maltose (6%) for Karnal local 95. Plantlet regeneration in the present study was found to be very low. Androgenic plantlets derived from the scented indica rice, Karnal local 95, were evaluated under field condition to assess variability among segregating A2 generation. Overall mean values in respect of some major agronomic characters viz. plant height, panicle length, number of filled grains per panicle, spikelet sterility (%) and grain yield per plant were reduced except number of panicles per plant. High CV was observed for filled grains per panicle, grains yield per plant and number of panicles per plant suggesting the existence of high variation among the androclones for those characters. Positive selection deems to be improvising those characters. The frequency distribution for number of panicles per plant and panicle length varied largely among the androclones in both direction of the parental mean. Whereas, all the androclones were found to be shorter than the parent and low yielder too. This study elucidates that the genetic modulation through exploitation of androclonal variation is a feasible proposition in scented indica rice.[...] Read More.

Keywords: Scented rice, anther culture, androclonal variation, genetic improvement.

Full text

Download：789

文章

Response of Musa species to macro-propagation. I: Genetic and initiation media effects on number, quality and survival of plantlets at prenursery and early nursery stages

Baiyeri, K. P.* and Aba, S. C.

Abstract: Ricehull and sawdust were evaluated as Musa sucker plantlet initiation media using five genotypes as test plants. Sword-sucker-corms whose apical dominance was physically destroyed were planted and evaluated for plantlet production during a period of about five months. The number, quality and pattern of plantlets produced and their survival were studied. Results showed that initiation media had statistically similar effects on most parameters measured. However, number of days to the emergence of the second and third plantlets was significantly (P[...] Read More.

Keywords: Musa genotypes, plantlets initiation media, survival in nursery.

Full text

Download：756

文章

Response of Musa species to macro-propagation. II: The effects of genotype, initiation and weaning media on sucker growth and quality in the nursery

Baiyeri K. P.

Abstract: Sucker plantlets of five Musa genotypes were derived from sword-sucker-corms using ricehull and sawdust as initiation media. Plantlets initiated were transferred to three weaning/rooting media formulated with ricehull (RH), sawdust (SD) and poultry manure (PM). Weaning media and genotypes had significant (P[...] Read More.

Keywords: Sucker-plantlets, weaning media, genotypic responses, growth quality.

Full text

Download：831

文章

Callus proliferation and somatic embryogenesis in cotton (Gossypium hirsutum L.)

Ikram-ul-Haq

Abstract: Somatic embryogenesis and plant regeneration are fundamental to tissue culture biotechnology in cotton (Gossypium hirsutum L.) cv. Coker 312. Callus proliferation was considered best on MS1a (2.0 mg/L NAA; 0.1 mg/L ZT; 0.1 mg/L KT) when 6 weeks old callus was cultured from MS1b (0.1 mg/L 2, 4- D; 0.5 mg/L KT) medium, there is no need to select embryogenic calli for somatic embryogenesis, as all of them were converted to somatic embryos. NH4NO3 play an important role in differentiation of callus into somatic embryos but is lethal for embryos just after two weeks. However, KNO 3 is less efficient for somatic embryo induction but is best for embryo maturation. By this procedure 56.51% cotyledenary embryos were developed within 5 weeks. Of that, 82.05% cotyledenary embryos were developed not only into normal plantlets, but rooted simultaneously when cultured on MS (with 0.05 mg/L GA3) medium. A complete plant of Cocker-312 could be regenerated through somatic embryogenesis within 4 to 5 months.[...] Read More.

Keywords: Gossypium hirsutum L,plant regeneration, Coker 312, callus induction, somatic embryogenesis, in vitro regeneration.

Full text

Download：758

文章

Role of bioinoculants in development of salt-tolerance of Vicia faba plants under salinity stress

G. H. Rabie* and A. M. Almadini

Abstract: Through biological inoculation technology, the bacterial-mycorrhizal-legume tripartite symbiosis in saline conditions was documented and the effects of dual inoculation with Azospirillum brasilense (NFB) and Arbuscular mycorrhizal (Am) fungus Glomus clarum on the host plants (Vicia faba) in pot cultures were investigated at five NaCl levels (0.0 – 6.0 dSm-1) in irrigating water. Am faba plants showed decreases in salinity tolerance, % of mycorrhizal infection and higher accumulation of proline with increasing levels of salinity. Am infection significantly increased tolerance of salinity, mycorrhizal dependency, phosphorus level, phosphatases enzymes, nodule number, nitrogen level, protein content and nitrogenase enzymes of all salinized faba plants in comparison with control and non-Am plants either in the absence and presence of NFB. In shoot system of non-Am plants, Na+ concentration was increased while the concentrations of K+, Mg+ and Ca+ were decreased with raising salinity stress. In Am plants, K+/Na+ , Mg+/Na+ and Ca+/Na+ ratios were higher than that of non-Am plants at all salinity levels. The Na+ level in shoots of Am plants showed slight increase with raising salinity meanwhile, K+ and Ca+ concentrations showed noticeable increases especially at higher salinity levels. The results clearly showed that the inoculation of NFB to Am plants had potentiality to increase the effects of Am fungi under salinity stress. This study provides evidence for benefits of NFB to Am fungus in the protection of host plants against the detrimental effects of salt. If so, bacterial- Am-legume tripartite symbioses could be a new approach to increase the salinity tolerance of legumes plants under salinity conditions.[...] Read More.

Keywords: legumes mineral nutrition, mycorrhiza, nitrogen fixing bacteria, symbioses.

Full text

Download：860

Search Filter