Articles
IN VITRO MUTATION INDUCTION FOR THE IMPROVEMENT OF MYCOSPHAERELLA FIJIENSIS RESISTANCE IN TWO BANANA CULTIVARS GROWN IN KENYA
Article number
897_59
Pages
427 – 437
Language
English
Abstract
Gamma irradiation was used to induce mutations in two popular Kenyan AAA dessert banana cultivars Kampala and Nyoro in an attempt to improve their resistance to black leaf streak disease (BLSD) caused by Mycosphaerella fijiensis. Intact and longitudinally dissected shoot tips of in vitro cultures were exposed to 11 doses of 60Co gamma (ranging from 0-100 Gy) at a dose rate of 8 Gy/min.
The M1V4 generation plants were evaluated for agronomic traits and screened for response to M. fijiensis in the greenhouse.
Irradiation induced a range of morphological and agronomic variations.
The infection and development phases of the disease were significantly longer for the mutagen-treated plants, suggesting higher resistance to M. fijiensis. Based on their superior performance and response to M. fijiensis, two gamma-irradiated (NYRTC35A, KAMPTC35B) and two non-irradiated (NYRTC5, KAMPTC4) lines of Nyoro and Kampala, respectively, were evaluated in the field.
Forty-five percent of the resistant Nyoro plants were late flowering, small in stature (<1 m), with thick pseudostems (40-45 cm in circumference), short internodes and deformed leaves.
They also produced smaller bunches with a 25-75% reduction in number and size of fingers.
Among the mutagen-treated Kampala plants, 5% were significantly taller than the control plants, with long internodes and large fruit.
Over two production cycles, the non-irradiated control plants were generally more susceptible to BLSD but had superior agronomic traits.
The results are discussed with respect to the application of in vitro mutation induction for banana improvement.
The M1V4 generation plants were evaluated for agronomic traits and screened for response to M. fijiensis in the greenhouse.
Irradiation induced a range of morphological and agronomic variations.
The infection and development phases of the disease were significantly longer for the mutagen-treated plants, suggesting higher resistance to M. fijiensis. Based on their superior performance and response to M. fijiensis, two gamma-irradiated (NYRTC35A, KAMPTC35B) and two non-irradiated (NYRTC5, KAMPTC4) lines of Nyoro and Kampala, respectively, were evaluated in the field.
Forty-five percent of the resistant Nyoro plants were late flowering, small in stature (<1 m), with thick pseudostems (40-45 cm in circumference), short internodes and deformed leaves.
They also produced smaller bunches with a 25-75% reduction in number and size of fingers.
Among the mutagen-treated Kampala plants, 5% were significantly taller than the control plants, with long internodes and large fruit.
Over two production cycles, the non-irradiated control plants were generally more susceptible to BLSD but had superior agronomic traits.
The results are discussed with respect to the application of in vitro mutation induction for banana improvement.
Publication
Authors
M. Mwangi, S.W. Waudo, E.M. Kahangi
Keywords
black leaf streak, irradiation, Musa, host response
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