Evaluation of Salt Tolerance (NaCl) in Tunisian Chili Pepper (Capsicum frutescens L.) on Growth, Mineral Analysis and Solutes Synthesis

Every year, more and more land becomes non-productive due to salinity which adversely affects the productivity and quality of most crops that is why salinity becomes a concern to be studied more to understand the mechanisms included and select the tolerant genotypes. In this context, this investigation was carried out to study the impact of NaCl on growth, mineral analysis and solutes synthesis in five Tunisian chili pepper (Capsicum frutescens L.) cultivars: Tebourba (Tb), Somaa (Sm), Korba (Kb), Awald Haffouzz (Aw) and Souk jedid (Sj). Thus, an experiment took place under greenhouse at Higher Institute of Agronomy, Chott Meriem, Tunisia and stress was induced during two months in water by NaCl (0, 2, 4, 6, 8, 10 and 12 g/l). Results showed that increasing salinity stress, for all cultivars, decreases the height and biomass (dry and fresh weight) of plant in addition to the relative water content. Also, a decline in K+ and Ca2+ amounts in roots and K+/Na+ ratio was recorded. However, Na+ content in roots and the biosynthesis of soluble sugars and soluble proteins in leaves increased. Awlad Haffouzz and Korba cultivars succefully tolerated highest salinity level by accumulating more K+, Ca2+ in roots and containing the highest concentrations of soluble sugars and soluble protein in their leaves contrary to Souk jedid cultivar, considered as the sensitive cultivar

Impact of salt stress (NaCl) on growth, chlorophyll content and fluorescence of Tunisian cultivars of chili pepper (Capsicum frutescens L.)

Salinity is considered as the most important abiotic stress limiting crop production and plants are known to be able continuing survive under this stress by involving many mechanisms. In this content, the present study was carried out to evaluate the impact of NaCl on some physiological and biochemical parameters in five Tunisian chili pepper (Capsicum frutescens L.) cultivars: Tebourba (Tb), Somaa (Sm), Korba (Kb), Awald Haffouzz (AW) and Souk jedid (Sj). Thus, an experiment of five months was carried out under greenhouse at Higher Institute of Agronomy, Chott Meriem, Tunisia and stress is induced by NaCl at 7 concentrations (0, 2, 4, 6, 8, 10 and 12g/l). Results showed that increasing salinity stress, for all cultivars, had a negative impact on roots (length, fresh and dry weights) and leaves (number and area). Also, chlorophyll (a and b) amount in addition to quantium yield (Fv/Fm) decreased significantly. However, biosynthesis of proline in leaves is activated. Awlad Haffouzz and Korba cultivars succefully tolerated highest salinity level by accumulating more proline in leaves and maintaining usually higher values in all parameters in opposition to Souk jedid cultivar. Taken together, our data partly explain the mechanism used to ovoid salt stress by pepper plants when excessive in the culture medium

Performance of Eight Varieties of Onion (<i>Allium cepa</i> L.) Cultivated under Open Field in Tunisia

A field experiment was conducted from September 2010 to July 2011 at Research Station Farm of Higher Institute of Agronomy, Chott Mariem, Sousse (Tunisia) in order to evaluate the performance of seven onion varieties: ‘GIZA 6’, ‘Red Amposta’, ‘Z6’, ‘Morada de Amposta’, ‘Yellow Dessex’, ‘Early Yellow Texas Grano 502’ and ‘Keep Red’ against the commonly grown variety ‘Blanc Hâtif de Paris’ under field conditions. The experiment was conducted in a randomized complete block design with three replications. Results obtained showed that onion varieties were significantly different when it comes to the plant and bulb morphological characteristics. Variety ‘Morada de Amposta’ recorded the highest leaf length (68.06 cm), pseudostem diameter (8.63 cm), number of leaves (8.71), plant height (76.95 cm),&nbsp; in addition to the greatest yields (32.88 t/ha) which were significantly (p&#8804;0.05) increased by respectively 66.2,&nbsp; 88.8,&nbsp; 2.1,&nbsp; 61.2, 63, 27.9&nbsp; and 28.4%&nbsp; compared to those obtained from the regular variety ‘Blanc Hâtif de Paris’. Variety ‘Blanc Hâtif de Paris’ was the earliest to maturity and recorded the most preferment bulb weight (155.02 g) and diameter (8.21 cm). ‘Keep Red’ variety had the highest height of the bulb (7.19 cm). Variety ‘Z6’ recorded the minimum data in all measured parameters

Performance of Eight Varieties of Onion (&lt;i&gt;Allium cepa&lt;/i&gt; L.) Cultivated under Open Field in Tunisia

A field experiment was conducted from September 2010 to July 2011 at Research Station Farm of Higher Institute of Agronomy, Chott Mariem, Sousse (Tunisia) in order to evaluate the performance of seven onion varieties: ‘GIZA 6’, ‘Red Amposta’, ‘Z6’, ‘Morada de Amposta’, ‘Yellow Dessex’, ‘Early Yellow Texas Grano 502’ and ‘Keep Red’ against the commonly grown variety ‘Blanc Hâtif de Paris’ under field conditions. The experiment was conducted in a randomized complete block design with three replications. Results obtained showed that onion varieties were significantly different when it comes to the plant and bulb morphological characteristics. Variety ‘Morada de Amposta’ recorded the highest leaf length (68.06 cm), pseudostem diameter (8.63 cm), number of leaves (8.71), plant height (76.95 cm),  in addition to the greatest yields (32.88 t/ha) which were significantly (p≤0.05) increased by respectively 66.2,  88.8,  2.1,  61.2, 63, 27.9  and 28.4%  compared to those obtained from the regular variety ‘Blanc Hâtif de Paris’. Variety ‘Blanc Hâtif de Paris’ was the earliest to maturity and recorded the most preferment bulb weight (155.02 g) and diameter (8.21 cm). ‘Keep Red’ variety had the highest height of the bulb (7.19 cm). Variety ‘Z6’ recorded the minimum data in all measured parameters

Seed priming for better growth and yield of safflower (Carthamus tinctorius) under saline condition

Salinity is considered as a major abiotic stress affecting crop production in arid and semi-arid region. In field condition, poor germination and decrease of seedling growth results in poor establishment and occasionally crop failure. Many research studies have shown that seed priming is an efficient method for increasing plant growth and improvement of yield in saline condition. That’s why; this experiment was conducted to evaluate the effects of KCl priming on the growth traits and yield of Tunisian safflower under salinity conditions. Seeds were primed with KCl (5 g/l) for 24 h at 20°C. Primed (P) and un-primed (NP) seeds were directly sown in the field and followed during eight months of plant cycle. Experiments were conducted using various water irrigations concentrations induced by NaCl (0, 3, 6, 9 and 12 g/l). Results showed that plant height of primed seeds was greater than that of un-primed seeds. Numbers of branches per plant, fresh and dry weight, heads number per plant, petals and grains yield of plants derived from primed seeds were higher compared with un-primed seeds

Generic Characterization of Apolar Metabolites in Red Chili Peppers (Capsicum frutescens L.) by Orbitrap Mass Spectrometry.

The aim of the present study was to develop a generic analytical method for the identification and quantitation of apolar plant metabolites in biomass using liquid chromatography–photodiode array–accurate mass mass spectrometry (LC-PDA-amMS). During this study, a single generic sample preparation protocol was applied to extract apolar plant metabolites. Compound identification was performed using a single generic screening method for apolar compounds without the need for dedicated fractionation. Such a generic approach renders vast amounts of information and is virtually limited by only the solubility and detector response of the metabolites of interest. Method validation confirmed that this approach is applicable for quantitative purposes. Furthermore, an identification–quantitation strategy based on amMS and molar extinction coefficients was used for carotenoids, eliminating the need for reference standards for each carotenoid. To challenge the validated method, chili peppers (Capsicum frutescens L.) were analyzed to unravel their complex phytochemical composition (carotenoids, glycolipids, glycerolipids, capsaicinoids, lipid-soluble vitamins)