The aim of the study was to analyze the proximate composition of Dragon fruit (Hylocereus undatus) and to develop dragon fruit jelly to assess its prospect in marketability. The proximate analysis showed moisture 87.90±0.03%, ash 87.90±0.03%, reducing sugar 4.50±0.04%, non-reducing sugar 3.50±0.01%, total sugar 8.00±0.01%, total soluble solid 11±0.13%, pH 4.20±0.02%, acidity 0.45±0.01% and vitamin-C 9.90±0.04%. Then the dragon fruit jelly was prepared with standard formulation (0.05%, 0.1% and 1.5% of pectin) was analyzed for its nutritional composition with standard method. The three samples contained more or less similar nutritional compositions. The products were stored at ambient temperature (27 0C to 34 0C) for a period of 6 months and quality parameters were assessed. During storage the changes in color, flavor, odor, TSS and pH was observed. No special change of ingredients was found during first 4 months of storage and a little change of pH was observed after 4th months. A taste panel consisting of 10 panelists adjudged the acceptability of the samples. The consumer preferences were measured by statistical analysis. Among the samples jelly containing 1.5% pectin secured the highest score for color, flavor, turbidity and overall acceptability. DOI: http://dx.doi.org/10.3329/agric.v10i2.13139 The Agriculturists 2012; 10(2) 29-35

Abstract:In this research work, a mathematical model for simulation of the solar radiation system has been developed by using a system dynamics methodology. Bangladesh is used here for model validation. The simulated results obtained from this model have compared with the experimental results and found reasonably a good agreement. Therefore the performance of the model is to be expected as satisfactory.

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Studies were conducted to identify Pseudomonas fluorescens isolates from a collection of bacteria isolated from bacterial haemorrhagic septicaemia infected carp and catfish, evaluate their antibiotic sensitivity pattern and screen the antibacterial activity of some medicinal plant extracts against the isolates.. A total of 10 isolates were identified as P. fluorescens by morphological, physiological and biochemical tests.In vitro antibiotic sensitivity test of the P. fluorescens isolates were conducted by disc diffusion method for seven antibiotics where, all of the isolates were found to be sensitive only against streptomycin and gentamycin but, most of the isolates (80%) were found resistant to chloramphenicol (C). Moreover, eighty percent of the isolates showed resistance to multiple antibiotics. A total of 118 plant extracts were screened for their antibacterial activity against the P. fluorescens isolates where the isolates exhibited sensitivity to 30 samples. Leaf extracts of Tamarindus indicus, Terminalia chebula, Citrus aurantifolia, Eugenia caryophyllata and Spondias pinnata were found to inhibit the growth of all of the P. fluorescens isolates.

This paper presents an optimum harvesting area of a convex and concave polygon for the path planning of a robot combine harvester. A convenient optimum harvesting area for a convex and concave polygon is proposed. The notion is that path planning specifically for a robot combine harvester is required to choose the crop field optimum harvesting area; otherwise, crop losses may occur during harvesting of the field. For a safe turning margin of the robot combine harvester, the surrounding crop near the boundary zone is cut twice or thrice by manual operation. However, this surrounding cutting crop is not exactly straight, and sometimes it is curved or meanders. In addition, path planning with a conventional AB point method in order to take a corner position from the global positioning system by visual observation is a time-consuming operation. A curved or meandering crop is not cut and left in the field during harvesting, and the harvesting area is not optimum. Therefore, a suitable N-polygon algorithm and split of convex hull and cross-point method for determining the optimum harvesting area for path planning are proposed, which reduce the crop losses in the field. The results show that this developed algorithm estimates the optimum harvesting area for a convex or concave polygon field and its corner vertices, takes all crop portions, and reduces crop losses. It is also illustrated that the working path calculated based on the corner vertices minimizes the total operational processing time. Keywords Convex polygon • Concave polygon • Optimum harvesting area • Path planning • Robot combine harvester 1 Introduction Development of an agricultural robot involves making the operator's work easier in the agricultural industry. The concept of a robot is required owing to the decreasing agricultural B Kazunobu Ishii