This research was conducted to study the effect of the chemical mutagen N-methyl-N-nitro-N-nitrosoguanidine (NTG)on the chromosomes of callus induced from mature bean embryos, Harvester cultivar. Seeds were treated with 0.2 or o.4 mM of the mutagen that mixed with different percentages of ethanol for 24 hrs. Calli were induced on MS medium in the presence of 0.5 mg/L of Benzyl adenine (BA), 1 mg/L Indole acetic acid (IAA) and 100 mg/L from each of Casein hydrolysate, Glycine, Asparagine, Tyrosine, and Myo-Inositol. Samples were pretreated with 1, 2- benzene dichloride, Para –dichlorobenzene, or Colchicine. Two different staining methods were used to stain the chromosomes from root tips and calli.The results showed that Para –dichlorobenzene is the best pretreatment for both root tips and callicells. However, the stain acetoorcein was the best for the root tips while Feulgen stain was the best for calli cells. Chromosome count showed that there were 22 chromosomes in all the cells of bean root tips (control). While a wide range of chromosome numbers were obtained from calli cells with or without mutagen treatment. Ninety six percent of the non treatedcalli gave the normal number of chromosomes while only 60% of calli treated with (0.4 mM+4% ethanol) gave the normal number of chromosomes. Calli cells from all the treatments showed chromosome multiplication except in the presence of ethanol.

Abstract:The present research was conducted to study salinity effect on callus growth and regeneration from the local Chilli pepper cultivar as well as calli content of capsaicin, phenylalanine, proline and ascorbic acid. The results showed that the Pericarp gave the highest fresh and dry weight of 511.6 mg and 56.95 mg respectively at 9 dSm -1 compared with other interactions. Moreover the lowest fresh and dry weight was recorded for the root calli grown at 12 dSm -1 . The highest regeneration percentage was 87.20% at 3 dSm -1 and the lowest was 6.70% at 9 dSm -1 . For explant effect on regeneration, the highest percentage was 71.1% for shoot tips and the lowest was 23.30 % from the pericarp. However no plants were regenerated at 12 dSm -1 from all explants and at 9 dSm -1 from calli induced from roots, placenta and pericarps. Calli induced from Pericarp contain significantly higher Proline amount at 12 dSm -1 which was 34.65 µg/g and the lowest was 2.57 µg/g at 3 dSm -1 . Moreover Phenylalanine ranged from 28.23 µg/g at 3 dSm -1 and 41.50 µg/g at 12 dSm -1 . While a wide range between the explants in the Ascorbic acid amount was recorded. The highest was 47.21 µg/g from the Placenta calli and the lowest was 0.98 µg/g from the Shoot tip calli. On the other hand calli produced from Placenta gave the highest amount of Capsaicin 53.11 µg/g at 9 dSm -1 which was not significantly different than the placenta and the pericarp at 12 dSm -1 and the shoot tips, placenta and the pericarp at 9 µg/g. In conclusion Chili pepper callus tolerated salinity via the accumulation of Ascorbic acid, Proline, Phenylalanine and Capsaicin. Moreover Chili Pepper grown In vitro under salt stress contained high amount of Capsaicin the important pharmaceutical compound. Finally pepper plants were regenerated from salt stressed calli might be salt tolerant under field conditions.

This research was conducted to produce salt tolerant tomato plants by using mutation and tissue culture techniques. Seeds of two Tomato cultivars (Super Regina and Trescantos) were treated with 2.0 mM of Sodium Azide NaN 3 for 4 h and sterilized with Sodium Hypochlorite (NaOCl) of (0.0, 1.0 or 3.0)%. The treated seeds were germinated on (MS) medium and shoot tips (1 cm) were used to induce calli on media supplemented with different hormones combinations. The produced calli were cultured on media of (6.5, 8.5, or 10.5) dSm -1 sodium chloride. Plants were then regenerated from the survival calli. The results showed that 3% NaOCl was the best sterilization treatment. Moreover the best growth regulator combinations were either 2 mg /L BA with 2 mg/L IAA or 0.5 mg of BA with 1 mg/L IAA. Since there was no significant difference between them, the last was recommended. Furthermore, salinity had negative effect on callus growth and (6.5 dSm -1 ) treatment showed significantly higher callus fresh and dry weights than the other treatments. No plants were produced from 10.5 dSm -1 treatment and Super Regina showed higher percentage of plant regeneration than Trescantos. Calli grown on 10.5 dSm -1 contained the highest Sodium and Chloride ions. Trescantos cultivar showed significantly higher calli sodium ions content compared with Super Regina. However, no significant differences between the two cultivars in the Chloride ion content were found. In conclusion it has been possible to induce and select salt tolerant tomato plants via in vitro mutation technique.