; Requesens et al., 2014 ; Zhang et al., 2014 ). A high rate of in vitro regeneration is the first prerequisite for successful transformation, but many woody perennials such as Malus species are rather recalcitrant to regeneration. The regeneration ability
Yi Tan, Baisha Li, Yi Wang, Ting Wu, Zhenhai Han, and Xinzhong Zhang
Shadia Nada, Siva Chennareddy, Stephen Goldman, Sairam Rudrabhatla, Shobha Devi Potlakayala, Puthyaparambil Josekutty, and Karelia Deepkamal
culture and regeneration is limited ( Castillo and Smith, 1997 ; Cherng-Kang and Chih-Cheng, 2009 ; Espino et al., 2004 ; Mendi et al., 2009 ; Takayama, 1990 ). This is particularly true for Begonia tuberhybrida . In fact, only limited data are
Li Xu, Suzhen Huang, Yulin Han, and Haiyan Yuan
). Somatic embryogenesis is the fastest system of plant regeneration and generally considered to be prerequisite for genetic transformation ( Jeknic et al., 1999 ; Karami et al., 2006 ). Therefore, several protocols for iris regeneration via somatic
Yeh-Jin Ahn and Grace Qianhong Chen
is highly recalcitrant to in vitro plant regeneration and genetic transformation. Recently, Agrobacterium -mediated transformation was reported in castor ( Malathi et al., 2006 ; Sujatha and Sailaja, 2005 ) using meristems of embryonic tips as
Sheila M. Colby, Adrian M. Juncosa, and Carole P. Meredith
Although grape is easily infected with Agrobacterium and plants can be regenerated routinely, it has proven recalcitrant to the recovery of transgenic plants. Anatomical and histochemical analyses of cocultivated regenerating leaf explants were used to investigate the compatibility of direct shoot organogenesis with Agrobacterium- mediated transformation. Leaves of Vitis vinifera L. cvs. French Colombard and Thompson Seedless were cocultivated with Agrobacterium tumefaciens containing a binary vector carrying kanamycin resistance (APH(3′)II) and (β- glucuronidase (GUS) genes. Explants were cultured on shoot-inducing medium containing levels of kanamycin inhibitory to the formation of untransformed shoots and assayed for GUS expression after 2 or 4 weeks. Cells expressing GUS were most frequently observed either at the cut surface, in vascular bundles, or in inner cortical cells of the petiole, but none of these regions produce adventitious shoots. GUS expression was also frequently found on leaf laminae, where it marked the center of a zone of cross-protected cells, but unwounded lamina cells never participated in shoot regeneration. Cells expressing GUS were found less frequently in the epidermal and subepidermal locations where exogenous, multicellular promeristem initiation occurred. These observations suggest that the direct shoot regeneration system used here could produce chimerally transformed plants, but is unsuitable for the routine production of uniformly transformed plants.
Jacob George, Harsh Pal Bais, G.A. Ravishankar, and P. Manilal
Response surface methodology was utilized in statistical optimization of three quality factors (the number of multiple shoots, shoot length, and number of leaves) pertaining to regeneration of plantlets from leaf calli of Decalepis hamiltonii Wight. & Arn. (swallow root). The variables evaluated were the levels of sucrose, BA, and NAA each at two different concentrations. Response surfaces for shoot length and multiple shoot number were useful in achieving optimal levels of media constituents and in understanding their interactions, but response surfaces for number of leaves were not. The data indicate that sucrose, BA, and NAA levels may be manipulated to increase or decrease quality factors chosen. This approach may be useful in developing a micropropagation protocol for D. hamiltonii. Chemical names used: benzyladenine (BA); napthaleneacetic acid (NAA).
Andrea Swanberg and Wenhao Dai
genes is important to elucidate the function of future-cloned resistant genes and interaction between phytoplasma and plant hosts. A regeneration system is a prerequisite for recovering transgenic plants. Many factors, including genotype ( Choi et al
Wenhao Dai and Cielo Castillo
, elite traits cannot be efficiently integrated into new plants ( Tobutt, 1993 ). In vitro mutation and gene transformation are being explored ( Rose et al., 2000 ). The objective of this study was to determine factors influencing regeneration of two
Chia-Yun Ko, Tsai-Yun Lin, Chin-Wen Ho, and Jei-Fu Shaw
example, naphthoquinones, which are traditional remedies for dry and irritating coughs, can be produced and extracted from cell suspensions and in vitro cultures of Venus fly trap ( Hook, 2001 ). Stable in vitro plantlet regeneration of the Venus fly trap
Nancy Santana-Buzzy, Adriana Canto-Flick, Felipe Barahona-Pérez, María del Carmen Montalvo-Peniche, Patricia Yolanda Zapata-Castillo, Anabel Solís-Ruiz, Amílcar Zaldívar-Collí, Omar Gutiérrez-Alonso, and María de Lourdes Miranda-Ham
To induce multiple shoots from habanero pepper (Capsicum chinense Jacq.), nodes and stem segments were cultivated in MS medium supplemented with varying concentrations of kinetin, benzyladenine, and thidiazuron. The effect of the age of the explant in the medium on shoot formation and their latter development into plants was assessed. Ethylene concentration was measured along the experiments. Thidiazuron was the key growth regulator in the process, which at 3.4 μm induced seven to eight shoots that developed into healthy plants per explant. Plantlets in nonventilated vessels, where ethylene concentration was 0.25 ± 0.1102 μL·L–1, showed early defoliation and the formation of calli on the leaves and stems.