Untitled

Abstract

To improve the regeneration efficiency of cassava (Manihot esculenta Crantz) in vitro, the effect of silver nitrate (AgNO 3 ) on shoot organogenesis from somatic cotyledons was assessed. Adding AgNO 3 to the regeneration medium improved the regeneration frequency and reduced callus formation in all tested cultivars. Both the extent of the response to and the optimum concentration of AgNO 3 were cultivar dependent. In the model cultivar MCol22, the use of AgNO 3 at concentrations between 4 and 12 mg l −1 increased shoot organogenesis frequency and the number of shoot primordia per explant, the maximum effect being observed on a medium containing 12 mg l −1 AgNO 3 . At this concentration, the frequency of shoot organogenesis was enhanced from 60 to 90%, while callus formation decreased from 100 to 5%. The highest shoot organogenesis rates were obtained by supplementing the medium with 2 and 1 mg l −1 AgNO 3 in KU50 and Hanatee, respectively, while cultivar T5 showed an optimum response at 4 mg l −1 . The shoots regenerated from explants cultured on a medium containing AgNO 3 were more elongated than those cultured on a medium without AgNO 3 . The application of AgNO 3 did not change the dose response of shoot organogenesis for the selective agents hygromycin and mannose.

Somatic embryogenesis and plant regeneration of cassava (Manihot esculenta Crantz) landraces from Cameroon

“…Consistent with previous reports on other cultivars (Hankoua et al 2005; Sofiari et al 1997; Zhang et al 2001), we found that secondary somatic embryogenesis was induced in all five Cameroonian cultivars assessed in this study. However, we found that the frequency and number of somatic embryos varied across cultivars.…”

“…These challenges, together with the fact that not all cultivated genotypes are amenable to breeding, not being able to produce flowers, make cassava improvement difficult. Thus, improvement through genetic engineering, which principally is carried out using Agrobacterium -mediated transformation of friable embryogenic callus (González et al 1998; Zhang et al 2001), has become a method of choice in cassava improvement.…”

Effect of the ethylene inhibitors silver nitrate, silver sulfate, and cobaltchloride on micropropagation and biochemical parameters in the cherryrootstocks CAB-6P and Gisela 6

“…In a similar way, AgNO 3 enhanced shoot regeneration of white marigold (Misra and Datta, 2001), cassava (Zang et al, 2001), Vanilla planifolia (Giridhar et al, 2001), Capsicum spp. (Kumar et al, 2003a), Coffea canephora (Kumar et al, 2003b), pomegranate (Punica granatum L.) (Naik and Chand, 2003), Morinda reticulata Gamble (Nair et al, 2012), perennial alfalfa (Medicago sativa) (Li et al, 2009) and Virginia-type peanut plants (Ozudogru et al, 2005).…”

Factors influencing efficiency of shoot regeneration in Ziziphus jujuba Mill. ‘Huizao’

“…Silver nitrate has been widely used in micro-propagation of many species either to lower hyperhydricity or to increase regeneration efficiency (Burgos and Alburquerque 2003;Zhang et al 2001;Ozudogru et al 2005;Fei et al 2000). Ag ?…”