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The present study was aimed to develop a cost-effective and efficient protocol for mass propagation of high-quality seedlings through tissue culture by using seaweed extract as biostimulants instead of synthetic chemicals. The nodal explant of field grown W. somnifera estabilised on Murashige and Skoogs medium (MS) and Gamborg B5 medium supplemented with six concentration of 2,4 D. The percentage of culture response from the nodal explant ranged from 44 to 80 and 3.0 mg l-1 2,4 D found to be best for callus induction. MS media containing different concentration of seaweed extract (10, 20, 40, 60, 80 and 100 %) were tested individually for shoot induction. The medium supplemented with 40 % seaweed extract exhibited maximum number of shoots with about 8.6 shoots/ callus and 80 % seaweed extract exhibited 4.3 shoots/ callus. It is evident from this study that seaweed extracts can be used as substitute for synthetic growth hormones for micropropagation of medicinally important plant W. somnifera for clonal propagation and conservation.
Background. According to the European Food Safety Authority (EFSA), fish, seafood and seaweeds are foodstuffs that significantly contribute to dietary arsenic intake. With the exception of some algal species, the dominant compounds of arsenic in such food products are the less toxic organic forms. Both the Joint FAO/ WHO Expert Committee on Food Additives (JECFA) and EFSA recommend that speciation studies be performed to determine the different chemical forms in which arsenic is present in food due to the differences in their toxicity. Knowing such compositions can thus enable a complete exposure assessment to be made. Objectives. Determination of total and inorganic arsenic contents in fish, their products, seafood and seaweeds present on the Polish market. This was then followed by an exposure assessment of consumers to inorganic arsenic in these foodstuffs. Materials and Methods. Total and inorganic arsenic was determined in 55 samples of fish, their products, seafood as well as seaweeds available on the market. The analytical method was hydride generation atomic absorption spectrometry (HGAAS), after dry ashing of samples and reduction of arsenic to arsenic hydride using sodium borohydride. In order to isolate only the inorganic forms of arsenic prior to mineralisation, samples were subjected to concentrated HCl hydrolysis, followed by reduction with hydrobromic acid and hydrazine sulphate after which triple chloroform extractions and triple 1M HCl re-extractions were performed. Exposure of adults was estimated in relation to the Benchmark Dose Lower Confidence Limit (BMDL05) as set by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) that resulted in a 0.5% increase in lung cancer (3.0 μg/kg body weight (b.w.) per day). Results. Mean total arsenic content from all investigated fish samples was 0.46 mg/kg (90th percentile 0.94 mg/kg), whilst the inorganic arsenic content never exceeded the detection limit of the analytical method used (0.025 mg/kg). In fish products, mean total arsenic concentration was 1.48 mg/kg (90th percentile: 2.42 mg/kg), whilst in seafood they were 0.87 mg/ kg (90th percentile: 2.23 mg/kg), for inorganic arsenic contamination at the 90th percentile was 0.043 mg/kg with most results however being less than 0.025 mg/kg. The highest inorganic arsenic levels were determined in the Hijiki algal species samples (102.7 mg/kg), whereas the other algal samples gave a mean inorganic concentration of 0.41 mg/kg (90th percentile 0.86 mg/kg). The estimated average adults exposure to inorganic arsenic in fish, seafood and seaweeds was less than 0.5% of the lowest BMDL0.5 dose. Only for the Hijiki seaweed it was at 4.9% BMDL0.5. Conclusions. Results demonstrate that dietary arsenic intake from fish, seafood and seaweed along with all their products do not constitute a significant health threat to consumers apart from the seaweed species Hizikia fusiformis in which over 40% of all the inorganic arsenic compounds were found.
The aim of the experiments carried out in a high, polyethylene in the years 2004- -2006 was to examine the influence of the algae preparation Bio-algeen S-90 on yield, mineral composition of fruits, content of assimilatory pigments, intensity of assimilation and transpiration and photosynthetic water use efficiency index of the cherry tomato cv. Conchita F1. The results on tomato yields proved significant differences in total and marketable yield under the influence of Bio-algeen. The biggest total and marketable yields were obtained when plants were treated three times with Bio-algeen. Bio-algeen also caused increase in content of mineral components in cherry tomato fruits. Three- and fourfold sprays increased the content of total nitrogen, phosphorus, potassium, calcium, zinc, iron and nitrates. Treating tomato plants with the preparation increased the content of assimilatory pigments of tomato. Increase in a number of Bio-algeen sprays led to higher contents of total, a and b chlorophyll and carotenoids in leaves. Intensity of assimilation and transpiration of the plants and water use efficiency index depended on number of plants spraying with Bio-algeen. Plants sprayed two and three times with Bio-algeen were characterized by greater transpiration and assimilation intensity, but also by smaller efficiency of water use index.
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With the rising awareness of the adverse effects of chemical pesticides, people are looking for organically grown vegetables. Consumers are increasingly choosing organic foods due to the perception that they are healthier than those conventionally grown. Vegetable crops are vulnerable to a range of pathogenic organisms that reduce yield by killing the plant or damaging the product, thus making it unmarketable. Soil-borne diseases are among the major factors contributing to low yields of organic produce. Apart from chemical pesticides there are several methods that can be used to protect crops from soil-borne pathogens. These include the introduction of biocontrol agents against soil-borne plant pathogens, plants with therapeutic effects and organic soil amendments that stimulate antagonistic activities of microorganisms to soil-borne diseases. The decomposition of organic matter in soil also results in the accumulation of specific compounds that may be antifungal or nematicidal. With the growing interest in organic vegetables, it is necessary to find non chemical means of plant disease control. This review describes the impact of soil-borne diseases on organic vegetables and methods used for their control.
Proximate composition of the three green seaweeds viz., Chaetomorpha aerea, Enteromorpha intestinalis, Enteromorpha compressa one brown seaweed Dictyota dichotoma and one red seaweed Gracilaria corticata was investigated by determination of protein, carbohydrates, lipid, moisture and ash content. In the present study, the total protein was recarded upper most in E. intestinalis and bare minimum in E. compressa. The maximum carbohydrates recorded in C. aerea and minimum in G. corticata. The lipid content was acquired upper limit in E. compressa and least in C. aerea. The ash and moisture content in following of 5 different seaweeds are as follows: 7.45mg/g, 3.91mg/g were recorded in the C. aerea, 8.52mg/g, 3.42mg/g in the E. intestinalis, 8.58mg/g, 3.75mg/g in the E. compressa, 9.47mg/g, 4.23mg/g in the D. dichotoma and 6.95mg/g, 3.98mg/g in G. corticata. The proximate composition of 5 different seaweed species exhibited high nutritional value for human consumption.
The objective of our study was to determine changes in protein and monosaccharide content in select grass species due to an application of the kelp species Ecklonia maxima extract. The field experiment was arranged as a randomized sub-block design (split-split-plot) with three replicates. The following factors were examined: growth stimulant with the trade name Kelpak SL, which was either applied at the rate of 2,000 dm3·ha-1 or not applied, pure-sown grass species, and cultivars (Dactylis glomerata, cv. Amila and Tukan; Festulolium braunii, cv. Felopa and Agula). Protein compounds and monosaccharides were determined in the dry matter of the tested grasses. The biostimulant Kelpak significantly increased both protein compounds and monosaccharides as well as the carbohydrate-protein ratio in the plants. The grass species and their cultivars had different levels of protein compounds and carbohydrates.
Seaweed extracts have been recently introduced to crop growing, particularly to sustainable agriculture, in many countries worldwide. However, our knowledge of the action produced by Kelpak is only fragmentary as it is influenced by a number of factors, for example crop plant species and extract application schedule. Our objective was to determine the effect of Kelpak SL on the content of selected microelements in two grass species. A field experiment was arranged in a randomized subblock design (split-split-plot) with three replicates. It was conducted at the Experimental Unit of the University of Natural Sciences and Humanities in Siedlce (Poland) and started in late April each year. The following factors were examined: pure stands of two grass species Dactylis glomerata L. (cv. Amila) and Festulolium braunii (K.Richt.) A. Camus (cv. Felopa) grown in a monoculture, a biostimulant distributed under the trade name Kelpak SL, applied at 2 dm3 ha-1 (no biostimulant in the control treatment), and nitrogen applied at 50, 100, 150 kg ha-1 (no nitrogen in the control). During the experiment, grass was cut three times a year. The plant material was subjected to chemical analyses to assess dry matter (by determining the moisture content), zinc, copper, iron and manganese. The application of Kelpak significantly increased the Zn, Cu, Fe and Mn content in the grass species tested, regardless of the remaining factors. The grass species did not differ significantly in their content of Zn, Cu, Fe and Mn. The concentrations of the microelements in both species were significantly affected by a dose of nitrogen. At higher nitrogen doses, the concentrations of Zn, Cu and Fe were lower, unlike the content of Mn, which increased. The Fe:Mn ratio in the dry matter of both grasses was 2.79, which indicates some manganese deficiency.
In this study, 12 taxa from the Chlorophyta, Phaeophyta and Rhodophyta were collected from different depths at Gemlik-Karacaali and Erdek-Ormanlı. A total of 175 specimens from these divisions were used to determine Total Protein (TP), Total Soluble Carbohydrate (TSCH) and Chlorophyll a (Chl a), Chlorophyll b (Chl b), Chlorophyll c (Chl c), total carotenoid (Car) contents and Chl b/Chl a, Chl c/Chl a, Car/Chl a, Car/Chl b, Car/Chl c ratios. TP, TSCH and pigment contents varied significantly with respect to the algal taxa, stations and depth distribution. In addition, individual differences were important in all of the measured parameters. The maximum TP contents (0.94%–31.03%) were determined in some of the Rhodophyta. In some green seaweeds belonging to the genus Ulva L., the TP content was determined between 2.9%–28.1%. Lower TP contents were determined in Cystoseira barbata (Good) C. Agardh (1.1%–4.3%). In contrast to TP contents, TSCH values were very low; maximum TSCH were determined in Ulva species, as were protein contents. In conclusion, the variations in TP, TSCH and pigment in 12 taxa of macroalgae were analysed according to station, depth, and environment.
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