Effect of gamma and ultraviolet irradiation on adventitious regeneration fromin vitrocultured pear leaves

✍ Scribed by C. Pinet-Leblay; F. X. Turpin; E. Chevreau

• Book ID: 104619534
• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 581 KB
• Volume: 62
• Category: Article
• ISSN: 0014-2336
• DOI: 10.1007/bf00041757

✦ Synopsis

Irradiation of in vitro explants and subsequent adventitious regeneration has been tested for 4 commercially important varieties of pear (Pyrus communis) with the aim to create mutants with a reduced susceptibility to fire-blight (Erwinia amylovora). The effect of gamma and ultraviolet irradiation of leaves on adventitious regeneration ability has been studied. The LD50 (50% decrease of regeneration) after gamma irradiation was genotype-dependent and was between 20 and 50 grays. The curves of regeneration showed a threshold dose underneath which none or a very slight decrease was registered. The decrease might result from cumulative events. After an ultraviolet irradiation as low as 62.5 J/m 2, the leaves became crumbly and rolled up, and their metabolism seemed to be altered. The LD50 was about 125 J/m 2 for all varieties and the decrease of regeneration was linear. Histological investigations showed leaves with flattened epidermal cells after ultraviolet irradiation and slack spongy parenchyma after gamma irradiation.