Recent Unique Research for Enhancing Micropropagation Protocol of Balanites aegyptiaca (L.) Via Mammalian Sex Hormones

Abstract

In the present study, trials were done to investigate the influence of supplementing Murashige and Skoog’s culture medium with mammalian sex hormones (progesterone, estrogen, testosterone, human chorionic gonadotropin (HCG) and anabolic steroids on enhancing regeneration of Balanites aegyptiaca L., in vitro. For this purpose, nodal segment explants which were excised from in vitro grown plantlets (5-6 weeks old) were cultured on MS medium supplemented with 0.5 mg/L BAP in addition to progesterone, estrogen, testosterone, HCG and anabolic steroids (1.0, 3.0 and 5.0 mg/L each). For rooting, the regenerated shoots were cultured on half strength, hormone-free MS medium (as a control) or supplemented with 1.0 mg/L anabolic steroids alone or combined with β-cyclodextrin (10 and 20mg/L) and/or IBA (1.0 and 2.0 mg/L). Results of the present study have revealed that impregnating the culture medium with mammalian sex hormones (MSHs) had, in the great majority, significant positive effects on number of shoots per explant, shoot length, number of leaves per single shoot, and leaf area of Balanites aegyptiaca after 5 weeks of incubation. For example, impregnating the culture medium with 5.0 mg/L testosterone had resulted in the maximum shoot length, number of leaves and leaf area (15.33cm, 29 and 2.78cmrespectively). The highest significant shoots number per explant reached up 4.0using 1.0 mg/L testosterone. On other hand, the least significant number of shoots/nodal segment, shoot length, number of leaves and mean leaf area were(1.0, 1.93cm, 3.67, and 0.1cmrespectively)in response to treatment with 5.0 mg/L HCG. The results obtained showed also that half strength MS medium supplemented with 1.0 mg/L anabolic steroid hormone with or without 1.0 mg/L IBA had the highest significant rooting percentage (75%) and number of rootlets per shoot (5.67). The highest significant root length (5.50cm) was obtained when regenerants were cultured on half strength MS medium supplemented with 1.0 mg/L anabolic steroids hormones combined with 20.0 mg/l βcyclodextrin. The obtained regenerants were easily acclimatized within 4 weeks and transferred to greenhouse with a survival percentage of 95%. The results obtained in this study may indicate the promising future role that mammalian sex hormones (MSHs) can play in enhancement of shoot and root morphogenesis in vitro