RESUMO A Gérbera (Gerbera jamesonii Bolus ex Hook. F.; Asteraceae) é uma das plantas ornamentais economicamente mais importantes devido ao seu valor estético. No presente estudo, estabelecemos um método de micropropagação para a produção em larga escala de material de plantio de qualidade de gérbera ‘Pink Melody’. Oitenta e seis por cento dos explantes do capítulo produziram brotos adventícios (15,44 ± 0,34 brotos por capítulo) em meio Murashige e Skoogs (MS) contendo 2 mg L-1 de 6-benzilaminopurina (BAP) após seis semanas de incubação. A maior taxa de multiplicação de brotos (17 brotos por explante) foi obtida em meio MS suplementado com BAP e meta-Topolina (cada um a 2 mg L-1) após oito semanas. Os micro-brotações foram enraizados com sucesso (91,35%) em meio MS de meia força contendo 2 mg L-1 de ácido indol-3-butírico (AIB) em quatro semanas. As plântulas micropropagadas foram aclimatadas com uma taxa de sobrevivência de 97,5% e produziram flores sem aberrações morfológicas visíveis.

ABSTRACT Gerbera (Gerbera jamesonii Bolus ex Hook. F.; Asteraceae), is one of the most economically important ornamental plants due to its aesthetic value. In the present study, we established a micropropagation method for the large-scale production of quality planting material of gerbera ‘Pink Melody’. Eighty-six percent of the capitulum explants produced adventitious shoots (15.44 ± 0.34 shoots per capitulum) on Murashige and Skoogs (MS) medium containing 2 mg L−1 6-benzylaminopurine (BAP) after six weeks of incubation. The highest shoot multiplication rate (17 shoots per explant) was obtained on MS medium supplemented with BAP and meta-Topolin (each at 2 mg L−1) after eight weeks. The micro-shoots were successfully rooted (91.35%) on half-strength MS medium containing 2 mg L−1 indole-3-butyric acid (IBA) within four weeks. The micropropagated plantlets were acclimatized with a 97.5% survival rate and produced flowers with no visible morphological aberrations.

ABSTRACT Genetic improvement of chickpea (Cicer arietinum L.), a recalcitrant crop, has been largely restricted owing to a lack of efficient regeneration methods. In this study, four chickpea genotypes (Giza 4, Giza 88, Giza 195, and Giza 531) were efficiently micropropagated using embryo axes and synthetic seeds developed using an encapsulation technique. Multiple shoots grew from embryo explants using 2 and 4 mg L-1 benzylaminopurine (BAP). The number of shoots for Giza 195 explants using 4 and 6 mg L-1 BAP were 5.8 and 6.2, respectively. The elongated shoots were transferred to two indole- 3-butyric acid (IBA) concentrations (50 and 100 mmol L-1) for root induction. A high rooting percentage (67%-100%) followed by successful acclimatization (70%-75%) was obtained for shoots dipped in 50 mmol L-1 IBA and cultured into an MS liquid medium. Apical buds from in vitro shoots were encapsulated in sodium alginate along with calcium chloride to produce synthetic seeds, which were successfully stored at 4 °C for 5 mo. Giza 195 and Giza 531 were better conserved than Giza 4 and Giza 88, with 70%-75% regrowth and recovery rates. These results confirmed an efficient regeneration protocol and synthetic seed production, which could be utilized for genetic transformations and crop improvement.

ABSTRACT Sweet potato (Ipomoea batatas [L.] Lam.) is an important food crop that is cultivated and consumed worldwide, and its nutritional value makes it especially important in developing countries. However, sweet potato plants produced using conventional vegetative propagation can be prone to several diseases, thereby hindering crop yield. Therefore, micropropagation techniques are useful for producing higher quality plant material. The aim of the present study was to determine the optimal medium formulation for the axillary shoot multiplication of single-node ‘Abees’ explants. The influences of cytokinins (6-benzyladenine [BA], kinetin, thidiazuron, and zeatin), gibberellic acid, phenylacetic acid, indole-3-butyric acid, silver nitrate, and oxalic acid, culture duration, and medium salt strength were investigated. Optimal proliferation was observed when shoots were cultured on half-strength MS medium that was supplemented with 2 mg L-1 BA and 100 mg L-1 oxalic acid for 2 wk, followed by culture on half-strength MS medium without plant growth regulators for 4 wk. In this medium, the greatest number of shoots (3.1) and total number of nodes (16.1) per explant were observed. All (100%) of the regenerated shoots were rooted and acclimatized, with a survival rate of 96% when transferred to ex vitro conditions and no morphological abnormalities.