In VitroMicropropagation ofAloe adigratanaReynolds Using Offshoot Cuttings

Abstract

is study aimed at developing a suitable and reproducible protocol for in vitro micropropagation of Aloe adigratana Reynolds using explants from offshoots with the help of the most commonly used plant growth regulators (PGRs). Explants were initiated in full-strength Murashige and Skoog (MS) media enriched with 0.2 mg/L benzylaminopurine (BAP) + 0.2 mg/L naphthaleneacetic acid (NAA). Shooting experiment was conducted in full-strength MS media enriched with 0/0, 0.5/0.5, 1.0/0.5, 1.5/0.5, and 2.0/ 0.5 mg/L BAP/NAA. Likewise, rooting experiment was carried out in half-strength MS media enriched with NAA at 0.5, 1.0, and 1.5 mg/L and indol-3-butyric acid (IBA) at 0.5, 1.0, and 1.5 mg/L. Finally, acclimatization study was conducted in greenhouse, nursery, and open field. e shooting response of the plant was best in MS media enriched with 1.0 mg/L BAP + 0.5 mg/L NAA.is media formulation resulted in the shortest mean number of days to shooting (14.00 ± 2.30 days), the highest mean shoot number (4.00 ± 3.40), and the second highest mean shoot length (8.60 ± 2.10 cm). IBA enhanced rooting at higher concentrations (1.0 and 1.5 mg/L), but NAA did the same at lower concentrations (0.5 and 1.0 mg/L). All plantlets (n � 62) survived primary acclimatization. Secondary acclimatization in composted and matured soil media under nursery and open field (sun light) condition produced 88 to 93% survival rate. e death of plantlets in the secondary acclimatization is accounted to mechanical damage. is study demonstrated that the tested PGRs were useful in enhancing the in vitro micropropagation of the plant. Future studies need to focus on optimizing the protocol for large-scale, commercial micropropagation.

In Vitro Micropropagation of Industrially and Medicinally Useful Plant Aloe trichosantha Berger Using Offshoot Cuttings

“…e values of the mean root length tend to decrease with increasing NAA concentration. Similar patterns were observed many species including A. adigratana [32], A. elegans [31], A. percrassa [22], A. polyphylla [36], and A. vera [42].…”

“…Though not much profound, the mean number of days to shooting decreases from 16.8 ± 0.8 with 0.5/0.5 mg/L BAP/NAA supplement to 15.5 ± 0.5 with 2.0/0.5 mg/L BAP/NAA. The use of BAP and NAA to enrich shoot proliferation MS agar media is critical in many species such as A. adigratana [ 32 ], A. barbadensis [ 35 ], A. elegans [ 31 ], A. polyphylla [ 36 ], and A. vera [ 11 ].…”

“…Compared to other Ethiopian aloes whose micropropagation capacities are studied, the rooting response of A. trichosantha is relatively quicker. The rooting responses of A. adigratana (15 to 24 days) [ 32 ], A. elegans (15 to 20 days) [ 31 ], and A. percrassa (15 to 17) [ 22 ] are slower by about one week. Moreover, several researchers have reported slower rooting responses in some genotypes of A. vera (23 to 28 days) [ 11 ] and A. barbadenesis (14 to 19 days) [ 40 , 41 ].…”

“…Many studies have been conducted with combinations of low concentrations of BAP and NAA (i.e., 0.10 to 0.50 mg/L) to initiate explants with outstanding results. Initiation of A. elegans Todaro with 0.25/ 0.10 mg/L BAP/NAA [31], A. adigratana Reynolds with 0.50/0.50 mg/L BAP/NAA [32], and A. percrassa Todaro with 0.20/0.20 BAP/NAA [22] produced 95 to 100% clean and viable explants. In fact, many of the viable explants of A. percrassa developed one to four shoots in four weeks.…”

“…us, many researchers observed 90 to 100% survival rate in many species of Aloe after primary acclimatization [22,31,32,36,[44][45][46].…”