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Abstract This study was carried out at the Experimental Station of Desert Research Centre in Wadi-Sudr- South Sinai through three successive seasons; 1993/1994, 1994/1995 and 1995/1996. The study includes treating grains of two cultivars of wheat and barley with two mutagens, one of them was irradiation (Gamma rays) and the” other was chemical mutagen (ethylene imine). The grains of the two cultivars (Sakha 92 of hexaploid wheat and Giza 123 of six-rowed barley) are treated with doses of gamma rays; 10, 20 and 30 Krad. While the other part of grains of the two varieties treated with three concentrations of ethylene imine; 0.15 %, 0.30 % and 0.45 %. Percentage of grain germination of both treated cultivars was count in lab since grain were exposed to water with 6500 p.p.m of sodium chloride. Grains were grown in complete randomized block design experiment for the wheat and barley cultivars for each mutagen in soil irrigated. with under-ground saline water (nearly 6500 to 7000 p.p.m.) Data were obtained on the M) plants, M2 and selected mutants from the grains ofM3• The study was classified into four main parts: 1. Salinity effect on the germination. 2. The mutagenic effect on the morphological and yield component characters under saline conditions. 3. Cytological-studies:- 3.a. Cytological behaviour of chromosomes in mitosis. 3.b. Cytological behaviour of chromosomes in meiosis. 4. The DNA quantity during interphase. L Salinity effect on the germination percentage of wheat and harley grain cultivars: The results showed that decreased _at the percentage in untreated grains. While it was highly decreased in wheat more than barley. Bath mutagens (gamma rays and ethylene imine) cused highly decreases in germination percentage in while, ethylene imine was more effective on germination percentage particularly in barley under 0.30 and 0.45% IL The mutagenic effect on the morphological characters and grain yield under saline conditions in Ml and M2. The mean values induced after gamma rays or ethylene imine treatments for wheat (Sakha92) and barley (Giza123) in different quantitive characters; plant height, no. of spikes per plant, no. of spikelets per spike, no. of grains per spike, 1000 grain weight and grain yield per main spike were recorded in Ml and M2 generations. In the case of wheat (Sakha92) the mean of plant height in M, generation was significantly reduced at all doses (10,20 and 30 Krad) of gamma rays but it was highly significant increased at all concentrations (0.15%, 0.30% and 0.45%) of ethylene imine. While significant increases in the mean values of plant height were observed after both gamma irradiation or ethylene imine treatment in M2 generation. Phenotypic, genotypic variances, genetic coefficient variation and heretability were increased after treatment with two mutagens but ethylene imine was more effect than gamma rays. The mean of no. of spike per plant in Ml generation was significantly decreased at all doses of gamma irradiation but it was highly significant increased at all concentrations of ethylene imine. While in M2 generation it was highly significant increased after all treatments of both gamma rays and ethylene imine. Calculation of genetic coefficient of variation indicated that the amount of genetic variances after ethylene imine. Hence, estimation of heretability after treatment with gamma rays generally resulted in high values than that obtained after ethylene imine treatment. The main of no. of spikelets per spike in Ml generation was significant and highly significant reduction at doses 20 and 30 Krad and it was insignificantly at 10 Krad, dose of gamma rays but it was slight reduction at 0.15% and slight increased at 0.30% and 0.45% concentration of ethylene imine. While significant increases were observed in M2 generation after both gamma rays and ethylene imine treatments. It is worth to note that this increment after gamma irradiation was more than that ethylene imine treatment. Estimated values of genetic coefficient of variation were lower after two doses (10 and 20 Krad) of gamma rays than ethylene imine. Accordingly, low heretability estimates were detected especially after 10 and 20 Krad of gamma rays as well as 0.45% concentration of ethylene imine. The mean of no. of grains per spike in MI generation was slight decrease at dose 10 Krad of gamma rays and at 0.15% and 0.30% concentrations of ethylene imine, but it was highly significant reduction at both of 30 Krad of gamma rays and at 0.45% concentration of-ethylene imine. While in M2 generation significant increment and with lowest genotypic variance, genetic coefficient of variation and heretability were detected after tow doses (10 and 20 Krad) of gamma rays but insignificant differences were detected of it after ethylene imine treatments. The mean of 1000 grain weight in Ml generation was highly significant reduction at doses 20 and 30 Krad and it was slight and not significant at 10 Krad of gamma rays it was highly significant reduction at all concentrations of ethylene imine. While in M2 generation it was highly significant decreases after all treatment by both gamma rays and ethylene imine. Both phenotypic and genotypic variances were increased proportionally as gamma rays doses increased, meanwhile 0.15% concentration of ethylene imine gave more variability than 0.30% and 0.45% concentration. High percentages of hertability were detected at all treatments. The mam of grin yield per main spike in the M1 generation was slight reduction at 10 Krad. But it was highly differences at 20 and 30 Krad while it was highly differences at all concentrations of ethylene imine. Meanwhile in the M2 generation with three doses and concentrations of both gamma rays and ethylene imine, there were inconstant mean performance significant decreases at 10Krad of gamma rays and 0.45% concentration of ethylene imine and it was highly significant decrease at 30 K.rad of gamma rays. For all other genetic parameters, they were increased proportionally as dose of each treatment increased. In the case of barley (Giza 123), the mean of plant height in the Ml generation was significantlyreduced at 30 Krad and highly significant increase at 10 Krad. But it was slightly reduced at all concentrations of ethylene imine, while in the M2 generation it is clear that· ethylene imine treatments were more effective in increasing the plant height than gamma irradiation. The mean of no. of spikes per plant in the M2 generation was significantly decreased after 10 and 20 Krad doses of gamma rays and it was highly significant increase after 0.15% concentration of ethylene imine. The dose 20 Krad of gamma rays gave the highest genetic coefficient of variations and high percentage of heretability. The mean of no. of spikeletes per spike in M1 generation was increased at 10 and 20 Krad and it was decreased non-significantly at 30 Krad of gamma rays. While in the M2 generation it was highly significant increment were proportionally accured after ethylene imine concentration treatments increased as well as at 30 Krad of gamma rays. Both mutagens caused as increased in genetic coefficient of variation. The mean of no. of grains per spike, in M1 generation it was highly significant increase at 10 and 20 Krad doses and slight decreased at 30 Krad of gamma rays but it was significant decrease at 0.30% and it was insignificant decreased at the other concentrations of ethylene imine, while in the M2 generation it was significantly reduced after irradiated with 10 Krad dose of gamma rays. However, ethylene imine treatments were found to increase the mean of this trait more effectively than did the higher dose (30 Krad) of gamma rays. the highest genotypic variance were accounted after 20 and 30 Krad doses. The. mean of 1000 grin weight in M] generation was a slight reduction at 20 Krad and it was highly significant decrease at 30 K.rad of gamma rays and at all concentrations (0.15%, 0.30% and 0.45%) of ethylene imine. While in the M2 generation it was significant reduction after treatment with both of gamma rays and ethylene imine, however 10 and 20 Krad doses of gamma rays were more effective then all concentrations of ethylene imine. The mean of spike yield in M) generation was slight reduction at 20 Krad and it was increased significantly at 10 Krad but it was insignificant decrease at 30 Krad dose of gamma rays. While it was slight Increases at 0.15% and 0.30% and it was found a significant reduction at 0.45% concentration of ethylene imine. Meanwhile in M2 generation highly significant increasing of yielding ability was detected after ethylene imine treatments. Both mutagens caused an increase in genetic coefficient variation. Heretability estimates were increasing at 20 and 30 Krad doses of gamma rays. from the M2 generation,mutants were selected and grown to arise the M3 generation. Data described the morphological and yield characters of these mutants as a result to irradiation with gamma rays and ethylene imine treatments of both wheat (Sakha92) and barley (Giza123) culivars. The macromutant types in wheat at both of gamma rays and ethylene imine treatments was comprised three mutations viz. No. of spikes per plant, 1000 kernel weight and spike yield per main spike. While in the case of barley (Giza123), the macromutant types at both of gamma rays and ethylene imine treatments comprised six mutations viz. plant height, no. of spikes per plant, no. of spikelets per spike, no. of” grains per spike, 1000 kernel weight and grain yield per main spike. The high frequency of each mutant type was relatively higher when using both of two mutagens with barley (Giza 123) III. CytologicalStudies The results showed that both mutagens (gamma rays and ethylene imine) caused an increase in somatic or PMC’s cells, while the effective of gamma rays is significantly higher than ethylene imine. Moreover, the quantities of chromosomal aberration. IV. The DNA quantity during interphases: from the results, the increasing of gamma rays doses on the percentage of cells DNA synthesis more effect in barley than wheat. Mean while, the increasing of ethylene imine concentrations increase the percentage of non divided cells and decrease the percentage of DNA synthesis cell sharply in wheat. On the other hand, in barley the increasing of ethylene imine concentrations increase gradually the percentage of non divided cells and decrease gradually the percentage of DNA synthesis cells compared with the control. Generally, the data indicated that, gamma ray doses more effect on wheat than barley. While ethylene imine more effect on barley than wheat. |