Ferdaous Guasmi

Physico-chemical properties and DPPH-ABTS scavenging activity of some local pomegranate (Punica granatum) ecotypes

Peels and fresh pomegranate extracts were used in the present study for the determination of the physic-chemical properties and DPPH-ABTS scavenging activities. Total sugars of juice are fructose (ca. 7 g/100 ml) and glucose (ca. 8 g/100 ml). Contents of soluble proteins in juice extracts are about 7 g/l (Bradford assays) and 22% (Kjeldhal assays) from dry pulp. Minerals in peel and juice are respectively 9.43±0.93 and 9.46±1.05 mg/100 ml for posphorus and 210.86±10.70 and 271.94±60.59 mg/100 g for potassium. The sodium contents are nearly 7 mg/100 ml in both peel and juice. Highly antioxidant contents in peels were confirmed. Free radical scavenging is about 3.58±0.38 µg/ml in peel. The antioxidant capacity value determined by ABTS was 7.364±0.403 mM Trolox equivalent antioxidant capacity/100 g dry weight. These findings implied that bio-active compounds from the peel might be potential resources for the development of antioxidant function dietary food.

Fatty acids from Tunisian and Chinese pomegranate (Punica granatum L.) seeds

Pomegranate seed oil is considered a powerful health-benefiting agent due to its anti-oxidative and anticarcinogenic properties. Lipids from 21 pomegranate cultivars (15 Tunisian and 6 Chinese) were extracted and fatty acids were identified. Total lipids (16% on a dry weight basis) are mainly unsaturated (ca. 88%). Qualitatively, the pomegranate fatty acid composition is identical. Quantitatively, the predominant fatty acid was linolenic acid (44.51–86.14%), followed by linoleic acid (3.57–13.92%), oleic acid (3.03–12.88%), palmitic acid (3.13–11.82%), stearic acid (1.68–15.64%), gadoleic acid (0.50–4.91%), lignoceric acid ( < 2.53%), arachidic acid ( < 1.70%) and myristic acid ( < 0.85%). Statistical methods revealed how Chinese and Tunisian pomegranate fatty acid contents may be affected by the sampling location.

The Use of ISSR and RAPD Markers for Genetic Diversity among South Tunisian Barley

Random amplified polymorphic DNA (RAPD) and intersimple sequence repeat (ISSR) were assayed to determine the genetic diversity of 80 barley specimens from South Tunisia. The ISSR primers showed variation in the percentage of polymorphism, band informativeness (Ib), and resolving power (Rp). The percentage of polymorphism is 66.67%, the average Ib ranged from 0.24 to 0.39, while Rp ranged from 0.74 to 1.16. In RAPD analysis, three primers yielded a total of 17 scorable bands, which are all polymorphic. The three polymorphic primers exhibited variation with regard to average band informativeness (AvIb) and resolving power (Rp). RAPD and ISSR marker systems were found to be useful for the genetic diversity among the barley specimens. The two dendrograms obtained through these markers show different clustering of 80 barely specimens, but we noted that some clusters were similar in some cases. A poor correlation (𝑟=0.12) was found between both sets of genetic similarity data, suggesting that both sets of markers revealed unrelated estimates of genetic relationships. Therefore, the ISSR and RAPD molecular markers show two genetic grouping of studied barely specimens.

Performance physiologique du génotype autotétraploïde induit de Trigonella foenum-graecum L. comparée aux génotypes diploïdes

Abstract Polyploid plants are distinguished from diploids by an improved photosynthetic capacity related to the increase of the photosynthetic enzymes and pigments quantities. The aim of this work was to study the physiological performances accompanying the experimental polyploidisation of Trigonella foenum- graecum by comparing the induced autotetraploid, the diploid resulting from the treated plants and the parent. Total chlorophylls content, photosynthesis rate, transpiration rate and stomatal conductance were measured for each genotype. Results showed highly significant variations (p < 0.01) between the different genotypes for the studied physiological characters. PCA and UPGMA method structured the genotypes in two groups. The first group is formed by the autotetraploids and the second is consisted by the parents and the diploids resulting from the treated plants.

INFLUENCE OF VARIOUS PHYSICAL PARAMETERS ON ANTHER CULTURE OF BARLEY

This study describes the effect of some parameters on anther culture of barley to optimize the plant regeneration condition of this species. The embryo formation and plant regeneration from anthers of three barley cultivars (‘Igri’, ‘Saida’ and ‘Libya’) were investigated. The effects of length of flag leaves, stage of microspore development, and pre-treatments (mannitol or cold pre-treatment) of anthers were investigated. Results showed significant responses. Anthers at the mid uninucleate to mid-late uninucleate stage gave the best anther culture response showing 80, 60, and 30% anther development in ‘Igri’, ‘Saida’ and ‘Libya’ barley cultivars, respectively. The use of mannitol (0.3 M) or 20 days cold pre-treatments showed the best results for embryo and green-plant production.

Répercussion de la polyploïdie artificielle sur la tolérance au stress salin chez Trigonella foenum-graecum L en Tunisie

Abstract Salinity is a global problem that limits crop production, especially on irrigated area in the world. The artificially induced polyploidy could make Trigonella foenum-graecum more tolerant to the salinity increase provoked by irrigation. The objective of this study was to compare salt stress tolerance of the induced autotetraploids, the diploids resulting from treated plants and the control diploids of Trigonella foenum-graecum. Morphological descriptors of these cytotypes, irrigated with water of 25, 50 and 100 mM of NaCl concentrations, was evaluated. The three cytotypes manifested a decrease of morphological characters measured values with the increase of NaCl concentration in irrigation water. Autotetraploid cytotype presented significant increases of these values compared to parent cytotype for the majority of studied characters. It seems more tolerant to NaCl salinity than its diploid parent.

Genetic variability of some cultivars of pistachio tree based in composition of vitamins

The identification and the characterisation of some cultivars of pistachio trees of the south of Tunisia were shown to have a remarkable diversity between different cultivars by using molecular markers (ISSR) supported by morphological markers [leaf length, leaf area, fruit length, terminal leaflet shape, length leaflet and chemical composition (content of vitamins)]. The content of vitamin B1 varied from zero in Kermizi, Meknessy 1, Mumtez, Mateur 2 and Mateur 3 varieties to 1.9 mg/100 g in Lybie rouge. For the vitamin B2 content, the value ranged from 0.1 mg/100 g in Mateur 3 variety to 7 mg/100 g in Lybie rouge. Vitamin B6 content varied from 0. 16 mg/100 g in Mateur 3 variety to 1.643 mg/100 g in Red Aleppo. Vitamin C vitamin content can reach 9 mg/100 g in Lybie blanc variety.

Morphological and molecular variability of some south Tunisian barley accessions.

Abstract A total of 20 accessions of barley (Hordeum vulgare L.) from arid regions of Tunisia were collected and evaluated ex situ in experimental fields (Medenine, South Tunisia). Morphological traits and molecular marker (Random Amplified polymorphic DNA) were applied to evaluate genetic diversity of these accessions. The study showed the existence of a highly significant phenotypical variability. Some parameters (production of straw and grain yield) appeared as good criteria to differentiate particular accessions. Concerning molecular variability, 49 RAPD bands were used to calculate Jaccards distance coefficient for cluster analysis using an arithmetic averaging algorithm (UPGMA). The genetic distance of the 20 studied accessions ranged between 0.25–0.68. The analysis of the hierarchical tree shows the presence of four ramifications thus translating great genetic diversity.

Création de variétés tolérantes au stress abiotique chez l'orge (Hordeum vulgare L.) par culture d'anthères

Abstract The study aims the creation of the pure barley variety, tolerant to the abiotic stress by anther culture. This study was concerned two variety of barley: cultivar Ardhaoui, selected for their best tolerance to the abiotic stress (salt and drought) collected from Tunisia, and cultivar Arige, from Syria, sensitive for the two types of stress. The androgenic aptitude was evaluated in the parents (Ardhaoui and Arige) and their hybrids (F1) by anther culture. The stage of setting in anther culture was given on the basis of morphological and cytological criteria. The result shows that the capacity of regeneration of cal differs from a genotype with another (it varies from 50% at the hybrids with 40% in the parent Arige). Following the results, it is important to announce that the rate of albinism which we observed is height, it especially exceeds 70% from Ardhaoui; it can be explained by the combination of several factors. Finally we can deduced that the majority of the regenerated planted are diploid (70%).

Répercussion de la polyplïdie sur le profil moléculaire ISSR et sur les contenus en vitamines et en protéines chez Trigonella foenum-graecum L.

Abstract Polyploidy constitutes a significant mechanism of genetic diversification and variability generation. The objective of this study is to compare molecular profiles, vitamins and proteins contents between the induced autotetraploids, the diploids resulting from treated plants and the control diploids. Molecular variability between these cultivars was studied using ISSR (Inter Simple Sequence Repeat) markers. Vitamins B6, B9 and C contents of the seeds were analysed by HPLC (High Performance Liquid Chromatography). Proteins contents of the seeds were analysed by the Bradford method. The mean heterozygosity between the three cultivars evaluated by the whole of the studied primers was weak (0, 06). The autotetraploids presented mean heterozygosity values higher than those of the diploïdes for 50 % of the studied primers. They presented higher vitamins B6 and B9 and higher albumin, prolamin and glutelin seed contents compared to the diploids resulting from the treated plants and the diploids parents.