The Presence of Beneficial Organisms Associated to N and P Economy in the Rhizosphere of Native Vegetation in an Oligotrophic Savanna of Guárico State, Venezuela

Background:In natural conditions, tropical plants are adapted to different ecological niches that can be associated to soil microorganisms which play a key role in nutrient cycling likeArbuscular mycorrhiza(AM), phosphate solubilizing bacteria (PSB) and/or nitrogen fixing rhizobia.Methods:We report a survey of the presence in a Trachypogon savanna located at Estación Experimental La Iguana (EELI) in Central Venezuela, of some beneficial plant-microorganism associations. In this savanna, plants present a high AM symbiosis affinity. The high mycorrhization and the presence of potential PSB suggest a synergic effect in plant P-uptake.Results:After screening the rhizospheres of 25 plant species from the zone, we could isolate a high proportion of potential PSB in relation to the total bacteria number from the rhizospheres ofCentrosema venosumandGalactia jussiaeana.Conclusion:Therefore, the presence of potential PSB in the rhizosphere of those species constitutes an important finding to discover novel biofertilizers for crop plants.

Acid Phosphatases Activity and Growth of Barley, Oat, Rye and Wheat Plants as Affected by Pi Deficiency

Objective: The influence of phosphorus deficit on the growth of plants and acid phosphatases activity in leaves and roots of barley seedlings (Hordeum vulgare L.), as well as oat (Avena sativa L.), rye (Secale cereale L.) and wheat plants (Triticum vulgare L.) was studied. Method: Plants were cultured three weeks in a nutrient media: complete (control, +P) or without phosphorus (-P). The growth on -P medium significantly affected the inorganic phosphate (Pi) content in plants tissues. Pi deficit decreased shoots growth but ratio of root/shoot was higher for -P plants when compared to control. The root elongation was enhanced under Pi deficiency - in -P oat and barley more intensive elongation was observed than in other plants. On the other hand, inhibition of shoot growth was more pronounced for -P rye and wheat. Pi-deficient plants showed higher activity of acid phosphatases in tissue extracts and in exudates from roots than +P plants. Result: Extracellular acid phosphatases activity increased the most for -P rye and wheat plants. Acid phosphatases secretion was intensive in growing parts of Pi-deficient roots. The activity of enzymes secreted by -P roots of all studied plants was higher than intracellular acid phosphatases. Conclusion: Our results indicated that wheat is more sensitive to the Pi deficiency at the early stage of growth than other plants, whereas oat is rather resistant to Pi deficit. The results suggested that acid phosphatases played an important role in acclimation of studied crop plants to moderate Pi deficiency.

Analysis of Brassinosteroids in Soybean Seeds and Leaves by Liquid Chromatography-Tandem Mass Spectrometry

Objective:A simple and fast high performance liquid chromatography-electrospray tandem mass spectrometry (LC-ESI-MS/MS) method has been developed for the analysis of brassinosteroids (BRs) in plants without derivatization.Materials:The BRs (including castasterone, 24-epicastasterone, brassinolide and 24-epibrassinolide) have been extracted with ice cold 80% aqueous methanol solution.Method:Five different purification strategies have been tested for the purification and enrichment of BRs.Conclusion:This analytical method was sensitive, reliable, rapid and applicable to trace analysis in complex plant samples.

Chlorella vulgaris as a Source of Essential Fatty Acids and Micronutrients: A Brief Commentary

Polyunsaturated fatty acids (PUFAs) comprise about 35-40% of the total lipid content from green algaeChlorella, reaching up to 24% linoleic acid and 27% α-linolenic acid inC. vulgaris. Also, microalgae nutrient composition may be modulated by changes in the culture medium, increasing fatty acid and microelement concentrations in the algae biomass. PUFAs, such as α-linolenic (n-3) and linoleic (n-6) acids, as well as its derivatives, are considered essential for dietary consumption, and their ability to regulate body chemistry has been recently explored in depth. A balanced fatty acid consumption is shown to counteract the negative effects of western diets, such as chronic inflammation and glucose intolerance. In this brief commentary, technological and practical uses ofC. vulgarisare explored as means to improve dietary quality and, ultimately, human health.

Chemical Constituents from the Rhizomes of Cyperus Rotundus L.

Background: Cyperus rotundus L. (Cyperaceae), is a perennial sedge distributed throughout India and other parts of the world. Its tubers are used as an appetizer, febrifuge and to treat bleeding, blisters, boils, cough, diarrhea, inflammation, lacteal disorders, rheumatoid arthritis, stomach ailments, skin rashes, thirst, vomiting, worm infestation and wounds. Objective: Our study was planned to isolate chemical constituents from the rhizomes of C. rotundus and to characterized their structures. Method: The air-dried rhizome powder was exhaustively extracted with methanol in a Soxhlet apparatus. The concentrated methanol extract was adsorbed on silica gel (60-120 mesh) for the preparation of a slurry. The dried slurry was chromatographed over silica gel column packed in petroleum ether. The column was eluted with petroleum ether, chloroform and methanol, successively, in order of increasing polarity to isolate the compounds. Results: Phytochemical investigation of the tubers led to isolate a sesquiterpenone characterized as 12-methyl cyprot-3-en-2-one-13-oic acid (1), two aliphatic ketone viz. n-dotriacontan-15-one (2) and n-tetracontan-7-one (8), fatty esters n-pentadecanyl octadec-9, 12- dienoate (n-pentadecanyl linoleate, 3), n-hexadecanyl linoleate (4), n-hexadecanyl oleate (5) and n-pentacos-13ʹ-enyl octadec-9-enoate (n-pentacos-13ʹ-enyl oleate, 9), two steroidal esters stigmast-5,22–dien-3β –olyl n-dodecanoate (stigmasterol laurate, 6) and stigmast-5, 22-dien-3β-olyl n-tetradecanoate (stigmasterol myristate, 7), β-sitosterol-3β-O-glucoside (10) and a triterpenic glycosidic ester lup-12, 20 (29)-dien-3β-ol-3-α-L-arabinopyranosyl-2'-oleate (lupenyl 3β-O-arabinpyranosyl 2′-oleate, 11). The structures of these compounds were established by spectral data analysis and chemical reactions. Conclusion: A sesquiterpene identified as cyprot-3-en-2-one-14-oic acid, two aliphatic ketones, fatty esters, two steroidal esters, β-sitosterol-3β-O-glucoside and lupenyl 3β-O-arabinpyranosyl 2′-oleate were isolated for the first time from the rhizomes.

Cultivation of New Emerging Agro-Nutritional Crop of Quinoa at Madinat al-Hikmah Karachi, Sindh, Pakistan

Aim: Quinoa is a popular source of protein, minerals and alternative to traditional grains. The objective of this study is to introduce the Quinoa in the semi-arid zone of Sindh province of Pakistan. Method: A variety of NARC-9 from the agricultural Punjab province was cultivated and subjected to analyze the growth, morphological characters of the varieties obtained, saponin, protein and the elemental composition viz. Cd, Cu, Fe, K, Na, Pb, and Zn. Result: The result demonstrated the optimum growth and no disease were found in the experimental area. At least three major varieties of quinoa were obtained. Seed morphological data of these three quinoa cultivars were collected. The average saponin levels were quite reasonable. Overall proteins band pattern revealed very high polymorphism in quinoa cultivars and the results were also in good agreement with earlier studies. Conclusion: All quinoa cultivars of Madinat al-Hikmah showed high concentrations of albumin than globulin concentrations (i.e. 48-52% and 24-27%, respectively) as compared to control seeds from market that had similar concentrations of the two fractions i.e. 35.58% and 37.68%, respectively. Likewise, low concentrations of prolamin 14-16% and glutelin 11-12% compared to control seeds 13% rank our crop much better quality than the imported one in the market. The trend of elemental accumulation was followed as K >Na >Fe >Zn >Cu >Pb >Cd, while for comparison it was Na >K >Zn >Fe >Cu >Pb >Cd >Pb for wheat grown under similar conditions. Traditional grains together make a major contribution to the total nutritional element intake of the average Pakistani citizen through diet, not only because of large amounts consumed, but also in part by suitable levels of their proteins and elemental up take for good health. Thus the successful cultivation of quinoa in the semi-arid zone of Sindh will certainly prove beneficial.

Synergistic Antitumor Effect of Genitinib (Iressa®) with Flavonoids from the Scutellaria baicalensis Root on the Non-Small Cell Lung Cells

Background: As was reported, gefitinib (Iressa®) showed a strong growth inhibitory effect on non-small-cell lung cancer PC-9 cells with mutant EGFR, but did not so much on A549 cells with wild-type EGFR. Observation: We here demonstrated by isobolograms and combination index analyses that the paired combinations of gefitinib with flavonoids from Wogon (Scutellaria baicalensis root): wogonin, oroxylin A and chrysin exerted synergistic anti-tumor effects against A549 cells. Result: The cell cycle analyses revealed that the combination of gefitinib and oroxylin A in A549 cells induced more apoptotic cells than other paired combinations as well as gefitinib alone. Thus, it is anticipated that oroxylin A could help to enhance the remission rate in the gefitinib therapy for the patients with non-small cell cancer cells with wild-type EGFR which provide a poor prognosis. Conclusion: Since the Wogon flavonoids, wogonin, oroxylin A and chrysin, accelerated the acetylation of Lysine residues of histone proteins, it is suggested that they put forth anti-tumor activities through inhibition of histone deacetylases which mediated the post-translational modification of histones.

Histochemical Examination of Invertase Activities in the Growing Tip of the Plant Root

Background:A growing part of the root is one of the most active sinks for sucrose coming from source leaves through the phloem. In the root, sucrose is unloaded from conducting bundles and is distributed among the surrounding cells. To be involved in the metabolism, sucrose should disintegrate into hexoses by means of degrading enzymes.Aims:The aim of this research was to explore the possibility of the involvement of one such enzymes, invertase, in phloem unloading as well as distribution of its activity in the functionally different tissues of the plant root tips.Method:To estimate the enzyme activities in root tissues, we applied two techniques: the histochemical method using nitro blue tetrazolium. The localization of phloem unloading was studied with carboxyfluorescein, a fluorescent marker for symplastic transport.Results:Invertase activity was not detected in the apical part of the meristem. It appeared only between the basal part of this zone and the beginning of the elongation zone. There is the root phloem unloading in that area. Invertase activity increased with increasing the distance from the root tip and reached the highest values in the region of cell transition to elongation and in the elongation zone. The activities of the enzyme varied in different tissues of the same zone and sometimes in the neighboring cells of the same tissue. Biochemical determination of invertase activity was made in the maize root segments coincident to the zones of meristem, cell elongation and differentiation. The results of both methods of determination of invertase activity were in agreement.Conclusion:It was concluded that phloem unloading correlated with invertase activity, possibly because of the activation of invertase by unloaded sucrose. Invertase is one of the factors involved in the processes preparing the cells for their transition to elongation because the concentration of osmotically active hexoses increases after cleavage of sucrose, that stimulates water entry into the cells, which is necessary for elongation growth.

Genetic Fidelity Testing Using SSR Marker Assay Confirms Trueness to Type of Micropropagated Coconut (Cocos nucifera L.) Plantlets Derived from Unfertilized Ovaries

Background: In vitro culture techniques provide an excellent platform for the multiplication of recalcitrant species such as coconut and thereby increase the homogeneity of the plantations. Clonal fidelity is one of the most important pre-requisites in a micropropagation protocol of crop species especially those with long life spans. Objective: The present study was conducted in order to determine the genetic homogeneity of coconut plantlets derived from unfertilized ovaries through somatic embryogenesis. Method: Twenty randomly selected plantlets at acclimatization stage, from two mother palms were subjected to Simple Sequence Repeats analysis. Thirteen highly polymorphic microsatellite primers were used for the detection of genetic fidelity in the clonal plantlets and their respective parent. Results: These plantlets showed no apparent differences among themselves and were comparable with the respective mother palm in the Simple Sequence Repeats analysis. The results obtained from this study suggest that there is no somaclonal variation or genetic instability occurring in plantlets that are regenerated from ovary explants. Conclusion: The absence of any sign of somaclonal variation suggests that somatic embryogenesis protocol did not induce the changes in gene structure, which had remained stable throughout the period that had been maintained in vitro. Determination of genetic fidelity of in vitro plants proved the suitability of regeneration protocol for large scale micropropagation applications for coconut.