Stable integration and expression of β-glucuronidase and NPT II genes in mango somatic embryos

Summary Somatic proembryos of mango (Mangifera indica L. cv. Hindi) were co-cultivated withAgrobacterium tumefaciens strain A208 harboring pTiT37-Se::pMON 9749 (9749 ASE). Transformed somatic proembryos capable of growing on selection medium containing 200 μg/ml kanamycin produced the characteristic indigo blue precipitate in the presence of 5-bromo-4-chloro-3-glucuronic acid. These proembryos were chimeral consisting of transformed (blue) and nontransformed (yellow/white) cells. A stepwise selection strategy was found necessary to eliminate chimeras. a) Initial screening at 200 μg/ml kanamycin to enable growth of transformed cells, b) further screening at 400 μg/ml kanamycin to reduce chimeras, and c) recovery of pure transformed clones of proembryos in liquid selection medium with 100 μg/ml kanamycin. The integration of the NPT II and GUS genes into mango genome was confirmed by Southern hybridization.     

Bioprospecting of thermo- and osmo-tolerant fungi from mango pulp–peel compost for bioethanol production

The persistent edaphic stress on microbial succession due to dynamic changes during composting was explored for selection of multi-stress tolerant microbe(s) desirable for ethanol production. A total of 23 strains were isolated from mango compost using four successive enrichments in YP broth (g l^?1): glucose, 100; 150; 250 with ethanol (40) and cycloheximide (0.4) at 40 °C, pH 6.0. Based on multi-gene ribotyping, 14 yeasts (61 %) of Saccharomycetaceae, 2 filamentous fungi (8.6 %) and 7 bacteria (30.4 %) were obtained. Phenetic and phylogenetic analysis of the 14 yeasts revealed 64.3 % tolerant to 500 g l^?1 glucose, growth at 45 °C and resemblance to Candida sp. (14.3 %), Kluyveromyces marxianus (35.7 %), Pichia kudriavzevii (21.4 %) and Saccharomyces cerevisiae (28.6 %). Assessment of the 14 yeasts in glucose fermentation medium (pH 4.5 at 40 °C) showed ethanol productivity of ≥92 % by 12 yeasts with theoretical yields of 90–97 %. Fermentation of molasses (150 g l^?1 glucose equivalent) by P. kudriavzevii D1C at 40 °C resulted in 73.70 ± 0.02 g l^?1 ethanol and productivity of 4.91 ± 0.01 g l^?1 h^?1. Assessment of P. kudriavzevii D1C revealed multi-stress tolerance towards 5-hydroxymethyl furfural, ethanol (20 %, v/v), high gravity and H₂O₂ (0.3 M) indicating suitability for ethanol production using high gravity molasses and pre-treated lignocellulosic biomass fermentation.     

The mango—its botany,cultivation, uses and future improvement,especially as observed in india

This delicious tropical fruit has been under cultivation tor about 4,000 years and today it is grown on about two million acres in India, its original home. Nearly 1,000 cultivated varieties are known throughout the tropics oi the world. The fruits are rich in vitamins A and C, and have better food value than apple.     

The antagonistic action of Trichoderma harzianum strain DGA01 against anthracnose-causing pathogen in mango cv. ‘Carabao’

The mechanisms of control and efficacy of Trichoderma harzianum strain DGA01 against anthracnose-causing pathogen Colletotrichum gloeosporioides in mango cv. ‘Carabao’ were examined. The action of DGA01 towards C. gloeosporioides was mycoparasitism and production of metabolites. DGA01 parasitised the pathogen by coiling its mycelia and spores on both artificial media and mango fruit surfaces. DGA01 was a parasitic necrotroph capable of killing C. gloeosporioides in 14 days of coexistence in artificial media. Dipping fruit in conidial suspension (10⁶?mL?L^?1) of DGA01 significantly decreased the incidence of anthracnose as compared to untreated fruit. Reduction in anthracnose severity was 87.90% showing high antagonistic potential of DGA01 in vivo.     

The antagonistic effect and mechanisms of Bacillus amyloliquefaciens DGA14 against anthracnose in mango cv. ‘Carabao’

Bacillus amyloliquefaciens strain DGA14 was tested for in vitro antagonism towards Colletotrichum gloeosporioides, a causal pathogen of anthracnose in mango cv. ‘Carabao’. DGA14 produced extracellular metabolites in solid and liquid media that suppressed the growth of C. gloeosporioides. The cells of DGA14 were often observed adjacent to the pathogen so affecting its spore germination and mycelium development. DGA14 colonised mango fruit 48 h after artificial inoculation and persisted 14 days after storage at 18–20°C. On fruit surfaces, DGA14 attached and produced dents to spores of C. gloeosporioides. Dipping mangoes in aqueous cell suspension (10⁸ mL L^?1) of DGA14 significantly decreased the incidence of anthracnose as compared to untreated fruit.     

Temporal effect of 2,4-D on induction of embryogenic nuclellar cultures and somatic embryo development of ‘Carabao’ mango

Summary Embryogenic nucellar cultures were established on B5 major salts, MS minor salts and organics, 400 mg/l⁻¹ glutamine, 60 g/l⁻¹ sucrose, 2 g/l⁻¹ gellan gum, and 4.5 μM 2,4-dichlorophenoxyacetic acid (2,4-D). There was no clear relationship between developmental age of the nucellar explants and induction of embryogenic cultures. The temporal requirements for culture initiation and for induction of embryogenic competence from nucellar explants were determined by pulsing the cultures for 0, 7, 14, 21, 28, 35, 42, 49, 56, and 63 d. Culture initiation required a minimum 7–14 d pulse with 2,4-D, and was maximum after a 56-d pulse; however, embryogenic competence was optimum after a minimum of 28 d exposure to 2,4-D. Somatic embryogenesis occurred directly from the nucellar explants at low frequencies. Somatic embryo maturation only occurred following plating of suspensions onto semisolid medium, and was stimulated by 2.4–4.8 μM kinetin and 4.4 μM 6-benzyladenine.     

Photochemical metabolism and fruit quality of Ubá mango tree exposed to combined light and heat stress in the field

Several experiments have highlighted the complexity of stress interactions, in field conditions, involved in plant response. However, these impacts on the mechanisms involved in plant photosynthetic response remains understudied. The aim of this work was to compare the photosynthetic efficiencies and fruit quality of mango tree (Mangifera indica L.) cv. Ubá harvested from plants cultivated on the east and west sides of a commercial orchard, according to the position of plants in relation to sunrise. Chlorophyll a fluorescence, was analyzed in leaves in four different periods: fruit growth phase, fruit ripening phase, post-harvest period and after plant pruning. Photoinhibitory damage was detected by the trapped energy flux and transported electron flux per reaction center during the fruit ripening phase, and by specific energy fluxes and yield quantum efficiency after plant pruning. Although high radiation caused photoinhibition on leaves from plants cultivated on the west side of the orchard, it provided sweeter fruits. In contrast to our initial hypothesis, it was verified that plants cultivated on the west side of the orchard presented better photochemical performance in periods with the greatest requirements of photoassimilates. In addition, plants demonstrated different abilities to deal with changes on photosynthetic active radiation and high temperature. This information suggests that the phenotypic plasticity of the Ubá mango cultivar is considerable, which can be exploited to be used in regions with great relief variations and the combination of increased irradiance and high temperature.     

Can a reductionist be a pluralist?

Pluralism is often put forth as a counter-position to reductionism. In this essay, I argue that reductionism and pluralism are in fact consistent. I propose that there are several potential goals for reductions and that the proper form of a reduction should be considered in tandem with the goal that it aims to achieve. This insight provides a basis for clarifying what version(s) of reductionism are currently defended, for explicating the notion of a fundamental level of explanation, and for showing how one can be both a reductionist and a pluralist.     

When is a parasite species a species?

Regrettably, 140 years after the publication of Darwin's Origin of Species, we face the grotesque situation that we still do not know what is a species whose origin Darwin wanted to explain. A generally applicable species definition is not available. Is there a basic unit of biodiversity above the level of individuals? Do we try to define something that does not exist in reality? The strong potential for the evolution of genetic variability in parasites together with the importance of species diagnosis for applied fields of parasite research make biodiversity research a key role in parasitology. Frequent occurrence of sympatric speciation, clonal reproduction, selfing, sib mating or parthenogenesis imply exceptional conditions for the evolution of gene pool diversities in parasites.     

When is a peroxisome not a peroxisome?

It is time to drop the glyoxysome name. Recent functional genomics analysis together with cell biology studies emphasize the unifying features of peroxisomes rather than their differences. Plant peroxisomes contain 300 or more proteins, the functions of which are dominated by activities related to fatty acid oxidation (>70 enzymes). By comparison, relatively few proteins are committed to metabolism of reactive oxygen species ( approximately 20) and to photorespiration ( approximately 10). Analysis of triglyceride metabolism in Arabidopsis seedlings now indicates that only two enzymes (isocitrate lyase and malate synthase) potentially distinguish glyoxysomes from other peroxisomes. Future research is best served by focusing on the common features of peroxisomes to establish how these dynamic organelles contribute to energy metabolism, development and responses to environmental challenges.