Community mobilization: a key to effective control of banana Xanthomonas wilt

Banana xanthomonas wilt (BXW) remains a major threat to banana, an important food and income crop for 12 million poor small-holder farmers in Uganda. Although, BXW has been controlled to some extent in parts of South-western Uganda, it is still a big problem in banana growing areas of Central and Eastern Uganda. We hypothesized that differential success in BXW control is mainly due to approaches used in the BXW control. This paper therefore, evaluates stakeholder mobilization approaches used in promoting technologies for BXW control in Uganda between 2006 and 2009. Results showed that farmer field schools host communities had more farmers (33%) that had low or no BXW infection (<10 infected plants) as compared to smaller proportions (23.5%) of farmers from communities that were using community action or that were mobilised using the traditional approach (22.9%) to control BXW. There was higher BXW prevalence in communities that were using community action (68.8%) or were mobilised traditionally (66.3%) than in those that hosted farmer field schools (43.4%). Consequently, there was higher (53%) banana production recovery on farms that hosted farmer field schools than those that used other institutional approaches (22%). BXW was better controlled by farmers mobilised using farmers field schools than those mobilized through community or traditional approaches

Rapid and efficient production of transgenic East African highland banana (Musa spp.) using intercalary meristematic tissues

East Africa is the largest banana producing and consuming region in Africa. In particular, the East African Highland Banana serves as the major staple crop of countries like Uganda, but production is constrained by a number of serious pests and diseases. Banana breeding is a very difficult and slow process, so genetic engineering offers an alternative approach to improvement. A transformation system using intercalary meristematic tissues was developed using Agrobacterium strain EHA105 harboring the binary vector pCAMBIA2301 containing the gusA reporter gene and nptII as selectable marker. In this paper, a new transformation protocol is described that yields kanamycin-resistant, GUSexpressing banana plants from roughly 10% of the initial explants. The resulting fully-rooted transgenic plants do not appear to be chimeras since they can be stably propagated, GUS activity is observed uniformly throughout the plants including the germline cells of the meristem, and PCR and Southern blots indicate stable integration of the genes into the genome

HUBUNGAN PANJANG TUNGKAI DENGAN KEMAMPUAN LOMPATRNJAUH PADA MAHASISWA PROGRAM STUDI PENJASKESREK FKIP UNIVERSITAS SYIAH KUALA TAHUN AKADEMIK 2012/2013

Banda Ace

Canopy management, leaf fall and litter quality of dominant tree species in the banana agroforestry system in Uganda

Small-scale farmers in the banana-coffee agro-zone of Central Uganda plant andmaintain trees to provide a range of benefits. However, the impact of trees on soil fertility and crop yields is small. On many farms, trees exist in infinite numbers, compositions, with no proper spacing, sequencing and canopy management  recommendations. The objectives of this study were to: quantify and compare leaf fall and leaf litter biomass for the dominant tree species subjected to different pruning regimes and during different seasons and determine the nutrient  concentrations in leaf litter materials in order to assess their potential to improve soil fertility. A survey was conducted on 30 randomly selected farms to examine and  document the tree species. Four tree species were dominant; Ficus natalensis (15.3%), Albizia coriaria (10.2%), Artocarpus  heterophyllus (10.0%) and Mangifera indica (9.2%). Experiments such as canopy pruning, collecting leaf fall and weights of pruned leaf biomass were established for the four dominant trees on five randomly selected farms. A total of 120 trees were subjected to three pruning regimes (0%, 25% and 50%). Litter traps (1 m × 1 m) were placed 2 m from the tree trunk to collect falling leaves. Leaf biomass was collected from pruned branches and eighed. Leaf samples were collected from pruned leaves and a composite sample analysed for carbon and nutrient concentrations. Results showed that 40 tree and shrub species belonging to 21 families existed on farms. Leaf fall was highest in the dry season and A. Heterophyllus registered the highest amount. Leaf biomass from pruned trees was heaviest for M. indica (42.4 ±3 kg) in the wet season and at the 50% pruning regime (45.7± 2.1kg). Total  nutrient concentrations were in the order A. coriaria&gt;F. natalensis&gt;A.heterophyllus&gt;M.indica. We concluded that F. natalensis and A. Coriaria should be integrated more into the agroforestry system to improve soil fertility. A.heterophyllus and M.indica should be planted on farm boundaries. The 50% pruning regime was the best and should be carried out during the wet season.Key words: Tree species, canopy management, leaf fall, nutrient concentrations, soil fertilit

Corm damage caused by banana weevils Cosmopolites sordidus (Germar) collected from different banana growing regions in Uganda

In this study, both healthy tissue culture plantlets and maiden suckers of the Nakitembe cultivar were used to assess the damage level variation caused by banana weevils collected from different banana growing regions. Seventy-nine (79) tissue culture plantlets and fifty (50) suckers were established in buckets in a randomized complete block design for 5 months. Ten adult weevils (5 females and 5 males) were introduced at the base of each plant, and the buckets were covered with a weevil proof mesh. Weevil damage was estimated as a percentage at 60 days after the weevil introduction by estimating the peripheral damage (PD), total cross section corm damage (XT ) and above the collar damage (ACD)

Agrobacterium mediated transformation of banana (Musa sp.) cv. Sukali Ndiizi (ABB) with a modified Carica papaya cystatin (CpCYS) gene

Conventional banana breeding for pest and disease resistance is a very difficult and slow process due to the limited sources of resistance, sterility of cultivated banana varieties, high polyploidy levels, long cropping cycle and the lack of rapid screening methods.Molecular breeding using the transgenic approach with candidate genes such as cystatins offers an alternative method to banana improvement. Cystatin proteins inhibit the activity of cysteine proteases responsible for the breakdown of dietary proteins in the gut of many pests including nematodes resulting in protein deficiency. In this study, the papaya cystatin gene was introduced into the banana genome. Embryogenic cell suspension (ECS) cultures of the banana cultivar Sukali Ndiizi (ABB) were used as explants material for the successful transformation of banana. The Carica papaya cystatin gene (CpCYS-Mut89) previously modified to improve its inhibitory potential against banana pests was introduced into this cultivar using Agrobacterium tumefaciens, strain LBA4404 and the gus reporter gene was used to observe successful transformation process. We report the successful protocol for routine transformation of this cultivar, which was completed in six months with plant regeneration observed at a frequency of 23%. An additional four months was required to multiply the regenerant lines in order to have at least 20 plants per line for downstream challenging studies. Putatively transgenic plants were analyzed by PCR using hpt and CpCYS - Mut89 specific primers to confirm the presence of trans genes. Out of 28 selected lines, 27 were positive for both hpt and CpCYS - Mut89 transgenes giving 96.4 % transformation efficiency. Fivelines were then selected on the basis of putative PCR positives and a Southern b lot analysis gave hybridization signals with 1 to 4 copy number integration patterns characteristic of Agrobacterium mediated transformation. These results confirm stable gene integration in East African banana cultivar cv. Sukali Ndiizi (genome group ABB) through an efficient Agrobacterium - mediated transformation protocol described for routine use in future improvement of this crop with genes of economic importance

Selection of cooking banana genotypes for yield and black Sigatoka resistance in different locations in Uganda

It is imperative to systematically evaluate new banana genotypes in different locations before national release. This enables selection and recommendation of superior genotypes as new varieties for a wider range of environments. The objective of the present study was to select banana genotypes with stable and high performance for bunch yield and leaf black Sigatoka resistance. Eleven cooking banana genotypes developed by the Uganda National Agricultural Research Organization in collaboration with Bioversity International, and two check varieties were evaluated in multi-location preliminary yield trials in Uganda. Data collected were analyzed using Additive Main Effects and Multiplicative Interaction (AMMI) model, AMMI Stability Value, and Genotype Selection Index (GSI). Genotype × location interaction was significant for all the traits assessed. Most of the new genotypes had low interaction effects with locations for bunch yield (69.2%) and black Sigatoka (92.3%). The most stable genotypes for bunch yield were NABIO815, NABIO1117, NABIO216 and NABIO306 whereas for black Sigatoka resistance, were NABIO1011, NABIO815, NABIO1009 and NABIO216. Using the GSI that defines the most desirable genotypes as those that combine high agronomic performance and stability across environments, four genotypes (NABIO306, NABIO1011, NABIO808 and NABIO1009) were selected. These genotypes, in addition to their high performance for agronomic traits and stability, had soft and yellow fruit pulp on cooking, and will be advanced on farm for further evaluatio

Application of pollen germination media on stigmas during pollination increases seed set in east African highland cooking bananas (Musa spp.)

Open Access Journal; Published online: 27 May 2021Seed set in East African Highland Cooking bananas (EAHBs) is extremely low and therefore hampers breeding. Pollen–pistil interaction is a key contributing factor. We assessed the effect of pollen germination media (PGM) on seed set in EAHBs. Five EAHB cultivars were pollinated with pollen from the wild banana ‘Calcutta 4’. Glucose-based PGM sprayed on freshly emerged stigmas significantly increased seed set per 100 fruits per bunch. Increases were 73.5% in ‘Enzirabahima’, 39.9% in ‘Mshale’, and 302.4% in ‘Nshonowa’. However, PGM did not increase seed set in the female sterile ‘Mlelembo’ and ‘Nakitembe’. As larger bunches were more fertile, good field management practices are also recommended to get more seed to improve breeding efficiency