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The objective of this study was to evaluate the phytochemical, antimicrobial, and insecticidal properties of tannins derived from Cydonia oblonga fruit.Qualitative and quantitative methods were used for the determination of the phytochemicals of Cydonia oblonga fruits. The tannins of this fruit were extracted using solvents and salts, and their antimicrobial activity against S. aureus ATCC 25923 and E.coli ATCC 25322 and C.albicans was investigated.The lethal effect of tannins extract was evaluated on Tribolium confusum under controlled laboratory conditions (at temperature 28 ± 2°C, relative humidity 75 ± 5%, and photoperiod of 16:8).The obtained results showed very interesting levels of tannins extraction (9.66%, 7.33%) using solvents and salts, respectively. The obtained tannins exerted no antimicrobial activity for the tested strains.On the other hand, all doses (50 μl, 100 μl, and 200 μl) of tannins tested on Tribolium confusum adults by the inhalation method showed a bioinsecticidal effect with an LD50 of 109.64 μl of tannin extract. Cydonia oblonga fruit can be an alternative for the development of natural drugs and insecticides with an important role in the fight against parasites.

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This work consists to study the storage system effect on thermal performance of an agricultural greenhouse in semi-arid climate case Ghardaia. The data climate is used for predict the energy needs as comparison with another without storage system. The obtained results indicate that the outside needs are less than the not heated with 3 to 5°C during winter night. Were the product rate being 2kg/day. The thermal behavior of the greenhouse was study numerically and the results are corroborating with the literature.

In this current contribution, a parametric investigation of air flow rate at the inlets of solar air collector was carried out. Through a developed Matlab code effort was made to show the effect of the air flow rate on solar collector outlet temperature. From the simulation results a database of outlet temperature and corresponding flow rate variation with time was created. Then, isotherm contours were deduced and plotted. For drying temperature kept constant at a given value regardless the meteorological conditions fluctuation, the flow rate variation with time was fitted by smoothing spline function. The simulation study was done for three different meteorological scenarios: Clear sky day, partly cloudy day and cloudy day. It has been found also that drying with variable flow rate at optimum temperature equal to 50 ±1°C the amount of air that was aspired at the inlet was 1207.8 kg. By contrast, drying with constant flow rate a total 625.5kg of air was aspired and it might result in fluctuation in drying temperature which affects the dried product quality. Thus variable flow rate allows a gain ratio in the aspired air amount of 93% and better product quality. This is valid for clear sky day. In case of partly and cloudy day, flow rate gain ratio was 104% and 78% respectively.

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