Ebrahim M. Khah

Chemical Composition and Yield of Six Genotypes of Common Purslane (Portulaca oleracea L.): An Alternative Source of Omega-3 Fatty Acids

Common purslane (Portulaca oleracea L.) is an annual weed rich in omega-3 fatty acids which is consumed for its edible leaves and stems. In the present study six different genotypes of common purslane (A-F) were evaluated for their nutritional value and chemical composition. Nutritional value and chemical composition depended on genotype. Oxalic acid content was the lowest for genotype D, whereas genotypes E and F are more promising for commercial cultivation, since they have low oxalic acid content. Genotype E had a very good antioxidant profile and a balanced composition of omega-3 and omega-6 fatty acids. Regarding yield, genotype A had the highest yield comparing to the other genotypes, whereas commercial varieties (E and F) did not differ from genotypes B and C. This study provides new information regarding common purslane bioactive compounds as affected by genotype and could be further implemented in food industry for products of high quality and increased added value.

Effect of nitrogen application on seed yield, pod and seed characteristics of okra

ABSTRACT Four okra cultivars [Abelmoschus esculentus (L.) Moench] were cultivated for two growing periods at nitrogen (N) application rates of 150, 300 and 450 mg N L−1. There was no effect of N on pod size (length and diameter) or on the number of seeds per pod and seed size (mean 1000 seed weight), all these characteristics of which related to the genotype. High N application (450 mg N L−1), increased the seed yield of the cultivar with the lowest flower induction (Boyiatiou), but only in experiment 2. In Veloudo, seed yield was highest at 300 mg N L−1, whereas in Pylaias and Clemson 450 mg N L−1 reduced seed yield. In all cultivars, seeds produced at an N rate of 450 mg N L−1 exhibited a significantly higher percent germination N, possibly by reducing the incidence of seed hardness.

Nitrogen application and sowing date affect okra pod and seed characteristics

ABSTRACT The effect of nitrogen (N) application rate and sowing date on seed quality and pod production of four cultivars of okra (Abelmoschus esculentus L.) were examined. Seeds of four okra cultivars (cv. ‘Boyatiou’, ‘Veloudo’, ‘Clemson’, and ‘Pylaias’) were sown on 13 May (1st sowing) and 2 June (2nd sowing). Plants were subjected to three N levels: F1, F2, and F3 (150, 300, and 450 mg N L−1). The 2nd sowing improved flower induction and pod set, without however affecting pod size. The number of seeds per pod was not affected by sowing time, but the mean 100 seed weight was generally lower in the 2nd sowing. In all cultivars, except cv. ‘Veloudo’ germination increased in the 2nd sowing mainly as a result of lower seed hardness. Germination was also improved by increasing N levels, or by seed storage, acid scarification, or seed priming.

Evaluation of Growth Media Incorporating Cotton Ginning By-products for Vegetable Production

The suitability of by-products from the cotton ginning industry for incorporation into growth media for three vegetable crops was examined. Composts were prepared by mixing the by-product with soil in 5 ratios (20:80, 40:60, 60:40, 80:20, 100:0, v/v compost and soil). Seeds of lettuce (Lactuca sativa L.), radish (Raphanus sativus L.) and spinach (Spinacia oleraceae L.) were sown directly within the composts and in 100% peat (control) in October (autumn crop) and December (winter crop). Plant growth (height, leaf number, dry and fresh weight, chlorophyll content) was recorded 19 and 17 days after transplantation (first and second sowing respectively) and at harvest. Fresh and dry weight was recorded at harvest. Overall, plant height and leaf number were higher when the growth media consisted principally of compost (higher ratios of cotton by-product: soil) than in the control (peat), whereas among the various ratios of compost: soil significant differences were recorded, media with a high compost content showing better growth in most cases. Similar results were reported for fresh and dry weight and chlorophyll content, except for dry weight in the second sowing, where growth media with a lower compost content had a higher dry weight. In conclusion, the incorporation of the cotton ginning by-product into compost resulted in better growth of lettuce, spinach and radish, suggesting that the use of this material may be of economical value as a spin-off product for the cotton ginning plant and also as a means of reducing present pollution of the environment due to the accumulation of waste material.