Yield performance of East African highland banana hybrids on farmers fields under high disease pressure

Abstract

The production of the East African highland cooking banana is constrained by pests, diseases and narrow genetic base amongst others. Research to develop resistant / tolerant genotypes has been on going at Kawanda. 18 promising banana hybrids have been identified. The hybrids were planted on farmers' fields in Kasangombe Sub-county in central Uganda for evaluation against black Sigatoka and yield. Data were collected on some of the agronomic traits, banana weevil damage and response to black Sigatoka disease on the plant and first ratoon crops. The data were analysed using mixed model procedures on SAS software. Means within each crop cycle were separated by comparing hem to Mbwazirume using adjustment to Dunnett's Test at 5% level of significance. The hybrids had more functional leaves (at least 9) compared to Mbwazirume (approximately 8 leaves). Youngest leaf spotted was significantly higher in the hybrids. All the hybrids except 2734K-1 retained significantly higher number of leaves at harvest (approximately 3 leaves). Most of the hybrids produced bigger bunches (at least 16 kg and 19 in the plant crop and first ratoon respectively) and the yield (t/ha/yr) of the banana hybrids was also higher compared to Mbwazirume. A Bi-plot of principal component analysis 1 against principal component analysis 2 showed that banana hybrids 12419S-13, 2625K-1 and 7798S-2 displayed very good agronomic traits in terms of plant height, girth and bunch weights. They also appeared to be tolerant to black Sigatoka disease as compared to Mbwazirume. These could be recommended for further evaluation with farmers to establish their culinary qualities and acceptability.

Distribution of Pseudocercospora species causing Sigatoka leaf diseases of banana in Uganda and Tanzania

“…All banana cultivars grown in the Great Lakes region were susceptible to black Sigatoka (Tushemereirwe et al , , ; Johanson et al , ; Erima et al , ). Previously, the cultivar Yangambi KM5 was resistant, exhibiting a hypersensitive response to P. fijiensis infection (Carlier et al , ).…”

Plantain hybrids for the humid forest agroecology of Central Africa – diseases and pests load, fruit yield and farmers perception

“…The total number of functional leaves at flowering has been reported as a good indicator of a plant's tolerance/resistance to pests and diseases and correlates strongly with bunch weight (Alvarez, 1997). All plantain genotypes had at least eight functional leaves at flowering which improved good bunch development and high-quality fruits (Erima et al, 2016). Noupadja et al (2007) and Boyé et al (2010) also reported that to obtain heavier bunches and to increase yields, a sufficient number of functional leaves must be present on the plant from flowering to harvest.…”

“…Additionally, the index of non-spotted leaves (INSL) was higher on improved genotypes compared with Ebang. Erima et al (2016) also mentioned that the high rank of the youngest leaf with streaks, of the youngest leaf, spotted and the high number of functional leaves at flowering shows the tolerance of a genotype against Black Sigatoka. It also correlates significantly with disease development time (Craenen, 1998).…”

“…This implies that most of the banana hybrids which had more than 8 leaves without spots, were tolerant to Black Sigatoka disease (Mobambo et al, 1996;Oluma et al, 2004). Therefore, the banana hybrids, because of the high index of the nonspotted leaf also had a high surface area to capture more radiant energy and greater potential for photosynthesizing and producing more assimilates which eventually promote the growth of large plantain bunches (Erima et al, 2016).…”

“…Indeed, there was a positive correlation (r = 0.30; P < 0.001) between the number of leaves at flowering and fruit yield and also between the number of standing leaves at harvest and fruit yield (r = 0.33; P < 0.001). Erima et al (2016) reported that the development of large and heavy banana bunches depends on the photosynthetic potential of the leaves -an increase in banana leaf area increases fruit production but this parameter will have some location specificity as photosynthetic activity is a function of leaf area and incident of solar radiation (Buah et al, 2000;Smithson et al, 2001). Large bunch weight and yield in bananas are also attributed to a higher growth rate before flowering and a high number of functional leaves at flowering and harvest (Erima et al, 2016), but genotype could be a more critical factor in determining the yield potential (Njuguna et al, 2010) which probably explains why some genotypes produced relatively smaller bunches even though they had a good number of functional leaves both at flowering and at harvest.…”