ARTURO PABLO ROS MURGADAS OBISPO AUXILIAR

In Uganda, an introduced landrace, hybrids, and elite endemic bananas have been diffused to farmers. In each community where these have been introduced, endemic Table 5.12 Results of hypothesis tests comparing distributions of

expected yield loss due to three constraints, by elevation, across use groups, Uganda

Use group

Kolmogorov-Smirnov test (p-value)

Black Sigatoka Weevils Fusarium wilt

Cooking cultivars 0.000 0.000 0.764

Beer cultivars 0.000 0.931 0.000

Sweet cultivars 0.000 0.324 0.412

Multiuse cultivars 0.359 0.775 0.099

Roasting cultivars 0.049 0.010 0.928

4 Expected yield losses were calculated in the following manner. First, farmers were asked about the incidence of the biotic pressure (in years) they had experienced during their involvement in banana production. Next, enu-merators elicited triangular yield distributions (minimum, maximum, and mode) in the presence and absence of the biotic pressures from farmers. Physical differences in the effects of pathogens on different banana cultivars were readily observable to them, and photos were provided to assist them in recognition. Expected yield losses were calculated, per biotic constraint and cultivar, from the elicited yield distributions (Hardaker, Huirne, and Anderson 1997; see Chapter 10 for formulas).

BANANA-GROWING HOUSEHOLDS AND BANANA CULTIVARS 59

EAHBs continue to dominate banana groves.

Yangambi Km 5 is a landrace or farmer cultivar, grouped here with hybrids only because it has been introduced recently.

Hybrids include FHIA01, FHIA03, FHIA17, and FHIA23. The elite endemic cultivar is Mpologoma. Mpologoma was selected, propa gated with tissue culture, and dissemi-nated by NARO. The estimated fraction of farmers using any type of improved banana in Uganda is only 9 percent (Table 5.13), all of whom are located in the low-elevation areas. Farmers in commercial growing areas of southwestern Uganda are generally more content with their available clones than those in less productive areas, such as the lowland areas of central Uganda, where productivity has declined. <Table 5.13 near here>

The average share of the banana groves allocated to improved cultivars among users is 13 percent. The numbers and mat shares in the exposed areas are both higher for elite endemic types than for exotics or hybrids (Table 5.14). Elite endemic types are pre-ferred farmers’ cultivars, disseminated with pest- and disease-free planting material. here><Table 5.14 near

Use rates are very low overall for the new hybrids diffused in Uganda. Previous field research suggests that the cooking quality is considered inferior for hybrids,

which is also reinforced by our findings (shown in Table 5.11). Two aspects of diffu-sion may also provide some explanation for low overall use rates. First, improved ba-nanas were disseminated by publicly funded programs in both Uganda and Tanzania, but appear to have been targeted in Uganda to fewer communities, most located in the low-lands. Consequently, only one-third of the villages surveyed in Uganda (9 of 27) had any adoption, while within those communi-ties, up to 65 percent of farmers grew exotic bananas or hybrids (see Appendix C). A second aspect of diffusion is that there is significant use of introduced bananas in nonexposed areas, where no program or project introductions had been made. The importance of farmer-to-farmer transfers of planting material for bananas, a vegetatively propagated crop, is salient.

In Tanzania, hybrid adoption rates are substantially higher than in Uganda, at-taining about 19 percent of farmers in Kagera Region during the survey year. Use of exotic materials is also much greater (Tables 5.15 and 5.16; for names, see Ap-pendix B). Again, however, the proportion of farmers growing hybrids was compara-ble between areas that were exposed and those that were not exposed,⁵ attesting to Table 5.13 Percentage of farmers growing improved banana cultivars, Uganda

Cultivar type

Elevation Exposure

All

Low High Exposed Not exposed

Exotic or hybrid 2.5** 0.0** 3.6 2.0 2.2

Elite endemic 7.5** 0.0** 6.2 6.7 6.7

All improved or introduced 9.9** 0.0** 9.5 8.7 8.8

Notes: ** indicates statistical significance at the 5 percent level in the difference of means or distributions across elevations within the country. Exotic refers to introduced farmers’ cultivars; elite endemic refers to endemic types selected and enhanced by the National Agricultural Research Organization; and all improved or introduced combines exotic, elite endemic, and hybrid categories.

5 The terms are defined in Chapter 2. “Exposure” means that the area has received introductions of planting material through a formal program or has been directly influenced by a program activity.

the effects of farmer-to-farmer diffusion.

This finding is consistent with the pattern estimated by the KCDP project, in Table 4.3 of Chapter 4. Farmer-based exchange more than offset project-based exchange, even when project efforts were as intensive as those undertaken in Kagera Region. <Table 5.15 near here><Table 5.16 near here>

Use of recommended banana-manage-ment practices was studied only in Uganda (Katungi 2006). Use rates for recommended management practices are much higher than for improved cultivars (Table 5.17).

How-ever, farmers use a wide range of organic fertilizers and sanitation practices to man-age their banana groves. They apply mulch (in the form of grass, crop residues, or household refuse) to control weeds, enable water penetration, and add nutrients to the soil when decomposed. Other organic fertil-izers are applied directly to the soil as or-ganic manure (that is, animal waste and composted household refuse). On average, mulching, animal manure, and soil and water conservation (SWC) bands are more Table 5.14 Number and share of banana mats planted to improved banana cultivars, by users, Uganda

Elevation Exposure

All

Cultivar type Low High Exposed Not exposed

Number of mats

Exotic or hybrid 7.9 0.0 5.4*** 8.3*** 7.9

Elite endemic 9.2 0.0 9.2*** 6.7*** 9.2

All improved 17.0** 0.0** 17.0*** 15.0*** 17.04

Mat share

Exotic or hybrid 0.03** 0.0** 0.1*** 0.02*** 0.03

Elite endemic 0.1* 0.0* 0.2** 0.1** 0.10

All improved 0.13** 0.0** 0.3*** 0.12*** 0.13

Notes: ***, **, and * indicate statistical significance at the 1 percent, 5 percent, and 10 percent levels, respectively, in the difference of means or distributions across elevation and exposure strata within country.

Mean number of mats in improved material is calculated only for those growing the improved material. A mat is a mother plant and all of its plantlets. Exotic refers to introduced farmers’ cultivars; elite endemic refers to endemic types selected and enhanced by the National Agricultural Research Organization; and all improved combines exotic, elite endemic, and hybrid categories.

Table 5.15 Percentage of farmers growing improved banana cultivars, Tanzania

Type of cultivar

Elevation Exposure

All

Low High Exposed Not exposed

Exotic 97.3 100 97.3 100 97.7

Hybrid 21.4*** 5.0*** 18.6 20 18.9

Either exotic or hybrid 97.3 100 97.3 100 97.7

Notes: Differences across strata are tested by cross-tabulation using the chi-square distribution. *** indicates statistical significance at the 1 percent level. Columns do not total because 35 households were found grow-ing both exotics and hybrids on their plots, reducgrow-ing the total number of households growgrow-ing at least one improved cultivar to 132 instead of 174. Exotic refers to introduced farmers’ cultivars.

BANANA-GROWING HOUSEHOLDS AND BANANA CULTIVARS 61

Table 5.16 Number and share of banana mats planted to improved banana cultivars, by users, Tanzania

Elevation Exposure

All

Cultivar type Low High Exposed Not exposed

Number of mats

Exotic 16.4*** 51.9*** 17.4** 40.8** 25.2

Hybrid 5.6*** 22.5*** 6.4 4.9 6.0

Exotic or hybrid 16.4*** 51.9*** 17.4** 40.8** 25.2

Mat share

Exotic 0.40*** 0.14*** 0.30** 0.38** 0.33

Hybrid 0.01** 0.001** 0.01 0.01 0.01

Exotic or hybrid 0.41*** 0.14*** 0.31** 0.39** 0.34

Notes: *** and ** indicate statistical significance at the 1 percent and 5 percent levels, respectively, in the difference of means or distributions across elevation and exposure strata within country. Exotic refers to introduced farmers’ cultivars.

Table 5.17 Percentage of farmers adopting selected banana management practices, Uganda

Practice

Elevation Exposure

All Low High Exposed Not exposed

Natural resource management

Mulching 66.5*** 91.9*** 73.5** 59.4** 75.1

Animal manure 35.6*** 64.6*** 37.8 33.3 45.4

Composting 17.01 15.2 26.5*** 7.3*** 16.4

Soil and water conservation

contour bands 9.8 15.2 16.3*** 3.1*** 11.6

Soil and water conservation

other bands 12.4*** 30.3*** 19.4*** 5.2*** 18.4

Mat management (sanitation practices)

Corm paring 18.9 14.3 33.0*** 6.1*** 17.3

Desuckering 73.5*** 92.9*** 79.4* 67.7* 79.9

Detrashing 95.4** 98.9** 97.9* 92.9* 95.6

Stumping 64.3*** 98.9*** 68.0 60.6 75.9

Splitting/chopping pseudostem 65.3*** 79.6*** 67.0 63.6 75.9

Corm removal 50 80.6 57.0*** 34.3*** 60.2

Weevil trapping 31.6 24.5 37.1 26.3 29.3

Note: ***, **, and * indicate statistical significance at the 1 percent, 5 percent, and 10 percent levels, respectively, in the difference of means or distributions across elevation and exposure strata within country.

frequently used in high-elevation areas (which are also in the southwest) than in low-elevation areas (Cen tral and Eastern regions). Use rates of most sanitation prac-tices (that is, desuckering, detrashing, stumping, and splitting/chopping pseudo-stem) were also significantly higher in high-elevation areas than in lowlands. In gen-eral, there is a significant difference in the management of bananas between the two major producing areas defined by altitude, probably due to differences in the produc-tion potential. Farmers in high-altitude areas have a greater incentive to manage their plants well, partly due to the more commercial nature of production. Rates of mulching, manure application, and water conservation reflect resource availability and, for bands, whether the planting is on slopes. <Table 5.17 near here>

Statistical differences in use of specific management practices are also evident ac-cording to exposure, although not for all practices. Adoption rates for mulching, composting, SWC bands, corm paring, de-trashing, desuckering, and corm removal were higher in exposed areas than in non-exposed areas. The adoption rates of SWC contour bands and stumping in low-altitude areas were observed to be slightly higher among relatively small holders (<2 ha), with no significant differences based on size for

other practices. Higher adoption rates for most of the banana management practices were found near paved roads, suggesting that improved access to markets and infor-mation may increase the diffusion of banana management practices.

Although many farmers report use of soil fertility management practices, the ex-tent of use per grove among the adopters is relatively low (Table 5.18). Significant dif-ferences in the number of mats grown under mulch (grass or crop residues) between the two elevation areas were found. The share of the plantation under all three organic fertilizers was higher in low-altitude areas than in highlands, implying a more binding constraint regarding access to the organic fertilizers for farmers in high-altitude areas, who are also comparatively large-scale ba-nana farmers. There are no meaningful dif-ferences in natural resource management practices by exposure, which suggests that elevation is a more important underlying parameter, because it is related to soil fertil-ity, pest and disease pressures, and the op-portunity cost of labor (Bagamba, 2007). here><Table 5.18 near

The extent of use of sanitation practices (measured by the extent of stumping and pseudostem splitting or chopping) was also significantly higher in high-elevation areas compared to low-elevation areas, and in exposed areas relative to nonexposed areas.

Table 5.18 Share of banana mats managed with recommended practices among users, Uganda

Practice

Elevation Exposure

All

Low High Exposed Not exposed

Natural resource management

Mats under mulch 0.35*** 0.12*** 0.38* 0.29* 0.26

Mats under animal manure 0.30*** 0.12*** 0.33 0.24 0.22

Mats under compost 0.30*** 0.11*** 0.31 0.26 0.25

Mat management

Proportion of stumps removed 0.47*** 0.64*** 0.56*** 0.35*** 0.54

Proportion of pseudostems split or chopped 0.26*** 0.59*** 0.33*** 0.16*** 0.38 Note: *** and * indicate statistical significance at the 1 percent and 10 percent levels, respectively, in the difference of means or distributions across elevation and exposure strata within countries.

BANANA-GROWING HOUSEHOLDS AND BANANA CULTIVARS 63

About 64 percent of the lower pseudostems⁶ are chopped off a few days after harvest, compared to 47 percent in low-elevation areas. Similarly, 59 percent of the upper pseudostems in high-elevation areas are ei-ther split or chopped soon after harvest, whereas only 26 percent of the upper pseu-dostems in the lowlands are managed accordingly.

Banana Planting Material