No abstract available

No abstract available

[en] A glasshouse experiment was carried out to evaluate the influence of liquid biofertilizer, oligochitosan and chemical fertilizer on the growth and yield of okra. The seedlings of okra were grown in pots containing approximately 4 kg of soil mixture, dispersed in complete randomized design (CRD) with 5 replications for each treatment. This experiment consisted of 5 treatments: control (without chemical fertilizer, oligochitosan and biofertilizer); T1 (100% chemical fertilizer), T2 (50 % chemical fertilizer, biofertilizer), T3 (50 % chemical fertilizer, oligochitosan); T4 (50 % chemical fertilizer, biofertilizer, oligochitosan) and T5 (50 % chemical fertilizer). After completion of the experiments (57 DAT), all the plants were harvested and separated according to parts viz., aboveground parts (stem, leaf, flower), roots and fruits to determine the growth characteristics and yield of the plant. In terms of plant growth, results showed that there were no significant difference on the leaf dimension and plant height among the treatments. Significant difference was detected in terms of fresh weight and dry weight of aboveground parts excluding the fruits. The fresh weight and dry weight of aboveground parts excluding the fruits are greatest in okra plant treated with combination of 50 % chemical fertilizer and biofertilizer. This result was comparable to okra plant treated with 100 % chemical fertilizer. The fresh weight of root for okra plant treated with combination of 50 % chemical fertilizer and biofertilizer was comparable to those treated with 100 % chemical fertilizer. In terms of plant yield, there was no significant difference shown among the treatments (number of fruit, fresh weight and dry weight of fruit). As conclusion, combination of all the three substances did not increase the growth and yield of greenhouse-grown okra. (author)

[en] Low cost and effective agriculture inputs are essential for sustainable agriculture production. Biofertilizer and liquid low molecular weight chitosan (LMC), otherwise well known as oligochitosan, produced from natural resources are alternatives to reduce dependency on chemical fertilizers and chemical based pesticides and pest repellents. Previous studies showed combination of biofertilizer and LMC enhanced productivity. Normal practices were to apply biofertilizer and LMC separately. These practices were labour intensive and time costing. Biofertilizer contains living microorganisms, and thus there was a concern on deleterious effect when oligochitosan was applied together with biofertilizer. The objective of the present study is to determine survival and shelf life of a biofertilizer microorganism in mixture with LMC. Acinetobacter baumannii (AP1) is a multifunctional biofertilizer bacterium with nitrogen (N₂) fixation, phosphate solubilisation and potassium solubilisation capabilities. AP1 was mixed with LMC. The mixtures were kept at room and cool temperature. The population of AP1 was determined monthly by serial dilution method. Results showed survival and shelf life of AP1 were good even after two months storage at room and cool temperature. The study will continue for up to six-month storage. (author)

[en] A newly isolated microbial inoculant showing potential as biofertilizer, M99 was evaluated for its effect on brassica plant in a greenhouse experiment. This experiment was carried out to evaluate the effect of M99 liquid biofertilizer (B), radiation processed chitosan (RPC) and chemical fertilizer (CF) on the growth and yield of brassica plant. The seedlings of brassica plant were grown in pots containing approximately 1.87 kg of soil mixture, dispersed in complete randomized design (CRD) with 20 replications for each treatment. This experiment consisted of 4 treatments: control (without CF, B, RPC); T1 (100% CF), T2 (B), T3 (RPC) and T4 (B, RPC). After completion of the experiment (33 DAT), the plants were harvested and separated according to parts viz., aboveground parts (stem, leaf) and roots to determine the growth characteristics and yield of the plant. Results showed that there was no significant difference among all the treatments in terms of leaf number. The tallest plant was observed in 100% CF treated brassica plant while the B and RPC treated plant did not show significant difference in plant height. Plant with longest root was observed in plant subjected to combination of B and RPC. In term of yield, the fresh weight and dry weight of aboveground plant (stem + leaves) of brassica plant treated with combination of B and RPC were comparable to 100 % CF treated plant. Synergistic effects between B and RPC on brassica plant were observed specifically in terms of root growth characteristics (length, fresh weight and dry weight) and yield (fresh weight and dry weight of aboveground parts). Combination of reduced amount of CF with B and O will be studied in the future. (author)

[en] Pathogenesis-related proteins have been described as proteins that are encoded by the plant genome and that are induced specifically in response to infections by pathogens. These represent a collection of unrelated protein families which function as part of the plant defense system. Pathogenesis-related antifungal protein has been isolated from the pulp of ripe Basrai bananas and purified through ammonium sulphate precipitation, Sephadex G- 75 gel filtration chromatography and electro-elution. The purified protein with acidic character (pI 6.81). has molecular weight of 34.5kDa, as determined by MALOI- TOF mass spectrometry. Mascot score obtained was 473 greater than 82, indicate extensive homology at a significant level (p.0.05) and the protein was identified as beta 1,3-glucanase with antifungal activity. It inhibited the growth of Fusarium oxysporum demonstrating the potential role of Basrai banana antifungal protein to control fungal diseases in plants, animals and human. (author)

[en] Research on basic characteristics and application of practical chitosan are need in order to understand their physical and chemical properties of this materials. One of the physico chemical properties that important for every polymers is absolute molecular weights. The important of this aspects has give big impacts on non colligative of the polymers, for example, viscosity, solubility and so on. Absolute weight molecular weights of each polymers can be measured by using GPC-MALLS. This device functioned as molecular size separator and molecular weight measurement by integration of the information such as sample concentration, light scattering index and sample reaction information using laser radiation irradiated from 18 angles.In this scope, we will discuss deeply on absolute weight molecular measurement of chitosan by using GPC-MALLS. (author)

No abstract available

[en] Insect cuticles as a natural biocomposite include many favorable microstructures which have been refined over centuries and endow the cuticles excellent mechanical and physical properties, such as light weight, high strength and toughness, etc. The various microstructures of a Scarabaei cuticle are investigated with a scanning electronic microscope and reported in this paper. It is found that the cuticle is a kind of fiber-reinforced biocomposite composed of chitin-fiber layers and sclerous protein matrixes. Different chitin-fiber layers have different orientations, composed of crossed and helicoidal structures at different location. In the helicoidal structure, each fiber layer rotates with an almost fixed angle against its neighboring layer. The maximum pullout energy of the helicoidal structure is analyzed based on the representative model of the structure. The result shows that the pullout energy of the helicoidal structure is markedly larger than that of the conventional 0^o-structure. A biomimetic composite with the observed helicoidal structure is designed and fabricated. A comparative test shows that the fracture toughness of the biomimetic composite is markedly larger than that of the 0^o-layer composite

[en] Biodegradable nanoparticles are intensively investigated for their potential applications in drug delivery systems. Being a biocompatible and biodegradable polymer, chitosan holds great promise for use in this area. This investigation was concerned with determination and optimization of the effective parameters involved in the production of chitosan nanoparticles using ionic gelation method. Studied variables were concentration and p H of the chitosan solution, the ratio of chitosan to sodium tripolyphosphate therein and the molecular weight of chitosan. For this purpose, Taguchi statistical method was used for design of experiments in three levels. The size of chitosan nanoparticle was determined using laser light scattering. The experimental results showed that concentration of chitosan solution was the most important parameter and chitosan molecular weight the least effective parameter. The optimum conditions for preparation of nanoparticles were found to be 1 mg/ml chitosan solution with p H=5, chitosan to sodium tripolyphosphate ratio of 3 and chitosan molecular weight of 200,000 daltons. The average nanoparticle size at optimum conditions was found to be about 150 nm