Transgenic apple plants overexpressing the Lc gene of maize show an altered growth habit and increased resistance to apple scab and fire blight.
Transgenic apple plants (Malus x domestica cv. 'Holsteiner Cox') overexpressing the Leaf Colour (Lc) gene from maize (Zea mays) exhibit strongly increased production of anthocyanins and flavan-3-ols (catechins, proanthocyanidins). Greenhouse plants investigated in this study exhibit altered phenotypes with regard to growth habit and resistance traits. Lc-transgenic plants show reduced size, transversal gravitropism of lateral shoots, reduced trichome development, and frequently reduced shoot diameter and abnormal leaf development with fused leaves. Such phenotypes seem to be in accordance with a direct or an indirect effect on polar-auxin-transport in the transgenic plants. Furthermore, leaves often develop necrotic lesions resembling hypersensitive response lesions. In tests, higher resistance against fire blight (caused by the bacterium Erwinia amylovora) and against scab (caused by the fungus Venturia inaequalis) is observed. These phenotypes are discussed with respect to the underlying altered physiology of the Lc-transgenic plants. The results are expected to be considered in apple breeding strategies.
Flachowsky
Henryk
H
Institute for Breeding Research on Horticultural and Fruit Crops, Julius Kühn-Institut, Federal Research Centre for Cultivated Plants, Pillnitzer Platz 3a, 01326 Dresden, Germany.
Szankowski
Iris
I
Fischer
Thilo C
TC
Richter
Klaus
K
Peil
Andreas
A
Höfer
Monika
M
Dörschel
Claudia
C
Schmoock
Sylvia
S
Gau
Achim E
AE
Halbwirth
Heidrun
H
Hanke
Magda-Viola
MV
D001203:Ascomycota; D044084:Erwinia amylovora; D007113:Immunity, Innate / Q000235:genetics; D027845:Malus / Q000235:genetics* / Q000254:growth & development / Q000382:microbiology; D010641:Phenotype; D010935:Plant Diseases / Q000382:microbiology*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000033:anatomy & histology / Q000254:growth & development* / Q000382:microbiology; D011003:Ploidies; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D003313:Zea mays / Q000235:genetics
D010940:Plant Proteins; D014157:Transcription Factors; C083017:R-S protein, Zea mays