Biological effects of ion beam irradiation on perennial gentian and apple

Abstract

The development of new varieties of perennial plants generally requires lengthy and laborious procedures. In this study, we used ion beam irradiation mutagenesis in an attempt to accelerate the breeding process for perennial plants. We evaluated the biological effects of five ion beam sources (carbon, neon, argon, silicon, and iron) and neutron irradiation on Japanese gentian and apple. These treatments were applied at the National Institute of Radiological Sciences (NIRS) using the Heavy Ion Medical Accelerator in Chiba (HIMAC) and the Neutron-exposure Accelerator System for Biological Effect Experiments (NASBEE). Biological effects were observed in in vitro gentian plants after irradiation with ion beams at <10 Gy, whereas apple trees were less sensitive to ion beam irradiation. The growth of gentians in vitro was repressed by 3 Gy neutron irradiation, while that of grafted apple trees was not affected by 4 Gy neutron irradiation. During in vitro proliferation, seven pink-flowered lines were obtained from originally blue-flowered gentian after C and Ne ion beam irradiation treatments. Genomic and reverse transcription-PCR analyses of these lines suggested that the mutations occurred in the genomic region containing F3′5′H (encoding flavonoid 3′,5′-hydroxylase). These results provide useful information for the mutagenesis and breeding of gentian, apple, and other perennial plants.

Application of the CRISPR/Cas9 system for modification of flower color in Torenia fournieri

“…For example, the production of flower-color mutants has been reported in various ornamental flowers, including cyclamens, Catharanthus and chrysanthemum, by ion-beam irradiation [ 1 , 2 ]. We also recently induced a flower color change from blue to pink in Japanese gentian, with a frequency as high as 8.3%, by ion-beam irradiation [ 3 ]. The most problematic aspect of this technique, however, is that flower color cannot be predicted in advance, and which genes are mutated remains unknown in mutagenesis breeding.…”

Morphological and cytological observations of corolla green spots reveal the presence of functional chloroplasts in Japanese gentian

“…The Japanese gentian breeding line 'Bzc-1' [19] was used in this study. The plants were grown in soil in pots under natural daylight in a greenhouse at the Iwate Agricultural Research Center (S2 Fig).…”

“…Using this information, molecular DNA markers to distinguish individuals with pink or white corollas from genotypes with blue-pigmented corollas have been developed [17,18]. Recently, novel technologies, such as radiation with heavy ion beams and genome editing using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9) system, have been applied to induce novel flower colors in gentian [19,20].…”

Effect of Three Types of Ion Beam Irradiation on Gerbera (Gerbera hybrida) In Vitro Shoots with Mutagenesis Efficiency

“…Ion beam technology was developed in Japan and is characterized by high mutagenesis efficiency, even at low doses, with minimal adverse effects on growth because it can deliver higher amounts of energy more locally than X-rays and γ-rays [ 6 ], which have been used for conventional mutagenesis [ 7 , 8 ]. There are many examples of mutants created by ion beam irradiation in plants, such as torenia [ 9 , 10 ], verbena [ 11 , 12 ], gentian [ 13 ], cyclamen [ 14 ], petunia [ 15 ], tricyrtis hirta [ 16 ], carnation [ 17 , 18 ], and Colocasia [ 19 ]. And the most common case of mutant production by ion beam irradiation is in chrysanthemum [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ], which are in the same family as gerbera, but it has not been reported in gerbera.…”