A. SOUISSI^1*,

R. HAMMAMI²,

T. STAMBOULI¹,

A. BENALAYA¹

¹  School of higher Eductaion in Agriculture of Mograne; Zaghouan, Tunisia

² National Institute of the Agricultural Research of Tunisia, Street Hédi Karray, 2049 Ariana-Tunisi

Abstract - Virtual water represents the volume of used water to produce an exchanged commodity through the international trade operations during its production process. In the case of agricultural products, many studies have sought to quantify the flows of virtual water exchanged around the world. Especially in countries facing water scarcity risks such is the case for Tunisia; the virtual water trade must be carefully studied as a potential solution for water shortage. The main objective of this paper is to consider a possible optimization of the agricultural water use through the estimation of the different types of virtual water for the most exported crops as well as for the main imported crops that can contribute to water saving. The monitoring of 478 farmers distributed throughout the country, allowed us to develop average techno-economic data sheets per bioclimatic stage and at the national level. These records allow estimates to be made of yields, production costs, revenue, gross margin and also to assess water consumption for each crop and consequently to estimate the virtual water content according to the water footprint network methodology. We have noticed that Tunisia can save up to 1.4 billion cubic meter of green water by importing wheat and about 5 million cubic meter of blue water by importing potatoes and onions. In the case of olive oil, we export about 2.46 billion cubic meter of green virtual water, which saves blue water for better allocation. Conversely, exports of dates are very expensive in terms of blue water, since 300 million cubic meter of blue water from non-renewable groundwater are exported. The results presented in this study can mainly help to establish policies for optimizing the use of water resources and improving water security in Tunisia.

Keywords: Virtual water, international trade, water security, water shortage, Tunisia

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R. HAMMAMI ¹,

T. STAMBOULI ²,

A. FRIJA ³,

A. SOUISSI ²,

A. BENALAYA ²

¹ National Institute of the Agricultural Research of Tunisia, Street Hédi Karray, 2049 Ariana-Tunisia

2 School of higher Eductaion in Agriculture of Mograne; Zaghouan, Tunisia

³ International Center for Agricultural Research in the Dry Areas (ICARDA), Amman, Jordanie

Abstract - This study aims the evaluation of the virtual water consumed by rainfed cereals and under complementary irrigation regimes in Tunisia with a sample of 150 farms. The main objective of this paper is to provide the necessary information for the policies formulations that integrate the concept of virtual water into the food security strategy in Tunisia, as well as to a better understanding of the role of farmers in the environment and water management. The methodology adopted is based on the estimation of the virtual water consumed by crops and on the calculation of some economic indicators such as the economic profitability of virtual water while being based on a typology of holdings per area stratum. Results show, the importance of complementary irrigation in reducing the quantity of virtual water consumed by cereals and, the need for a practical management of irrigation which will increase yields in the productive cereal regions and a better saving of water by adopting irrigation schedules according to the vegetative cycle of the plant and the climatic requirements.

Keywords: Cereals, Virtual Water, Irrigation, Tunisia

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E. JEDIDI NEJI*¹,

K. BEN MAHMOUD²,

R. BOUHLAL BEN HADJ ALOUANE¹,

A. JEMMALI²

¹ Laboratory of horticulture, National Institute of Agronomic Research of Tunisia. Rue Hedi Karray, 1004, El- menzah, Tunisia.

² Laboratory of Plant Protection, National Institute of Agronomic Research of Tunisia. Rue Hedi Karray, 1004, El- menzah, Tunisia.

Abstract - In cactus prickly pear (Opuntia ficus indica (O.f.i)), seeds are known to be essential for normal growth of fruits. Indeed, fruit size and shape are determined by seed number and distribution. The particularity is that the edible pulp tissue develops from the funiculi and external integuments of the seed coat. The fruits may contain both normal and aborted seeds and in some cases, aborted ones may be able to partially contribute to the pulp tissue regeneration. The present work was carried on a clone belonging O.f.i. in order to see if without emasculation gibberellic acid may be useful in fruit parthenocarpy. For this purpose, treatments consisting in injection of gibberellic acid GA₃ 0, 100 and 500 ppm were applied on pollinated or emasculated flowers before anthesis. Effects of these treatments have been studied at the level of fruit and seed development, pulp quality at maturity. The percentage of weight loss, peel thickness, total soluble solids and acidity of fruits were evaluated. The number of normal and aborted seeds was also evaluated and the morphology of these seeds was characterized visually and with the scanning electronic microscopy. GA₃ application allowed ovules of all treated flowers to give partially developed seeds that were able to ensure sufficient support for fruit development over then 60% compared to control. In this way, emasculation is not necessary to produce GA₃-mediated parthenocarpic cactus fruits.

Keywords: Opuntia ficus indica, cactus pear , fruit development, Gibberellic acid , parthenocarpy

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I. SMATI,

I. BETTAIEB REBEY*,

M. HAMMAMI,

G. HAMDAOUI,

M. SAIDAI TOUNSI

Laboratory of Medicinal and Aromatic Plants Biotechnology Center of Borj Cedria, Hammam-Lif 2050, Tunisia.

Abstract - The aim of the present work was to characterize Citrus limon juice during his fruit ripening by studying the quality parameters, aroma and polyphenol composition as well as the antioxidant activity of juice. It was found that the maturity of consumption of lemon juice is characterized by the highest yield of juice, a deacidification as well as the highest total sugars and ascorbic acid amounts with maturity index of around 1.46, which makes our fruit suitable for consumption. Aroma composition of this Tunisian variety is also rich in limonene, while the phenolic profile is characterized by the ascendancy of flavonoids and in particular the rutine. On the other hand, the antioxidant activity of lemon juice was evaluated and the greatest inhibition of DPPH was detected at the end of maturity.

Keywords: Citrus limon, juice, maturation, aroma, polyphenols, antioxidant

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