Sugarcane is one of the most important crops in the world for its syrup and by-products. Eight sugarcane genotypes (i.e.G.T.54-9, F.153, Co.997, Co.775, and F.161) were kindly provided by Sugar Crops Research Institute (SCRI), they were selected depending on previous screening of SCRI germplasm for studying the efficiency of technique that combined Random Amplified Polymorphic DNA (RAPD) and Inter Simple Sequence Repeats (ISSRs) as marker to assist selection for drought tolerance in sugarcane and compared it with RAPD and ISSR each separately. This technique is called R-ISSR.The performances of studied genotypes revealed that RAPD, ISSR, and R-ISSR techniques are useful as marker assisted selection for drought tolerance in sugarcane. 26 positive and negative markers were obtained from used techniques (RAPD, ISSR and R-ISSR), which would be used as marker to assist selection for drought tolerance. The study revealed that R-ISSR technique was more efficiency in this case. The study encourages breeder to use R-ISSR technique in the early selection for drought tolerance through sugarcane breeding programs.

Eight sugarcane genotypes (i.e.G.T.54-9, F.153, Co.997, Co.775, F.161) were selected depending on previous screening of Sugar Crops Research Institute (SCRI) germplasm for detecting morphological parameters and some molecular markers which could assist selection for drought tolerance in sugarcane using Simple Sequence Repeats (SSRs). The eight sugarcane genotypes were screened for drought tolerance depending on five traits (i.e. stalk height, stalk diameter, stalk weight, leaf area and number of stalks /m 2 ) in two dislocated experiments (sandy culture and open field experiments), where molecular studies were carried out. All studied genotypes were significantly affected by drought in both field and sandy culture experiments. The most affected trait was stalk weight which had the highest reduction percentage (21.55 and 28.93%), followed by No. stalk/m 2 (15.22 and 19.7 %) in sandy culture and field experiments, respectively. The highest reduction percentage was recorded for genotype Co775 with leaf area trait (39.88 %) in field experiment and stalk weight (64.44 %) in sandy culture. The most drought tolerant genotypes were Sp8032-80, Co997 and BOT41, while the most sensitive were Co775, F153 and F161.The performances of studied genotypes revealed the ability of using SSR technique as marker assisted selection for drought tolerance in sugarcane, in this context three positive and negative markers were obtained. Primer SSR15 produced one band with molecular weight 123 bp which could be used as marker for drought sensitivity (negative marker), however, SSR80 produced two bands 24 bp and 35 bp that could be used as negative and positive markers. This data would help the exploitation of sugarcane germplasm on molecular basis, so we highly recommend using SSR as marker assisted selection for drought tolerance in sugarcane.

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