Impact of cowpea breeding and storage research in Cameroon - IITA

More documents

Recommendations

Info

Cowpea postharvest and socioeconomic studies not include insecticide or heating treatments, insecticide loss and heating are measured by data on the solar disinfestations (4% after six months). Hermetic storage loss is estimated with data from the triple bagging treatment (4% after six months). Each of these loss estimates assumes that cowpea put into storage has an initial damage level like that of Vya after three months on a danki in pod form (4.3%). Vya is typical of many local cowpea varieties that are not particularly resistant to bruchids in pod form. While it is clear that the actual storage situation is much more complicated than this set of simple categories and loss rates, it is argued that the weighted average loss (52%) is a reasonable estimate. Insecticides and ash are not always used correctly and higher losses may result. In particular, a lower proportion of ash may be used (often because of a lack of an adequate quantity of ash) or the second insecticide treatment after three months may be omitted. Some Cameroonian botanicals may reduce storage losses, even though that has not yet been proven in the laboratory. Thus, ash and insecticide losses may be somewhat higher than estimated and the herbs and “nothing” category losses may be lower, but these offset each other. If the baseline loss parameter (δ) is 52%, the model loss parameter (φ) is 2.09. The loss reduction for solar heating (α) is 1.04 (φ) –1/(1–0.043)). Pod resistance is a characteristic of the newly developed varieties Lori Niébé and CRSP Niébé. This would affect the damage that occurs before the cowpeas are threshed. For the model, on-farm trial data with BR1 and BR2 were used. After three months on a danki these varieties showed only 0.8% damage, compared to the 4.3% with Vya. The 0.8% was then used as the starting damage in the six-month storage estimates. This is done by recalibrating the logistic function used to estimate losses to pass through an initial level of 0.8%, instead of 4.3%. With the 0.8% initial damage, the weighted average loss (δ) is 50% and an alpha parameter (α = 0.10) is 10%. Storage costs Storage costs were estimated based on data provided by Lowenberg-DeBoer (1994). All technologies except ash and triple bagging were assumed to store grain in woven sacks, valued at 250 FCFA for those that can hold 80 kg. Ash is stored in large clay pots called cannari commonly used to hold water in northern Cameroon. New pots are valued at 1500 FCFA and can hold about 50 kg of cowpea when mixed 50/50 with ash. They are assumed to last for five years. Plastic bags are valued at 150 FCFA/bag and are assumed to be used for one season because of the risk that reused bags may have small holes. Insecticide is valued at 175 FCFA/packet with one packet treating 80 kg seed every three months. The solar heater is composed of two sheets of plastic, one clear the other black, valued at 3500 FCFA and given a useful life of two years. The estimate used the high volume estimate outlined by Lowenberg-DeBoer in which 4000 kg seed are treated per year per solar heater. For lack of data, labor is assumed to be the same for all technologies at 100 FCFA/hour. The interest cost on the durable investment is annual, while the interest on variable cost in the model (r) is semiannual. Using the estimates, the initial nominal cost of storage is 6049 FCFA/t or 7117 in 1998 FCFA. The nominal cost for the solar heater is 4166 FCFA/t or 4902 in 1998 FCFA. Thus the storage cost reduction is estimated at 2215 FCFA in 1998 FCFA. 416
Impact of cowpea breeding and storage research in Cameroon Yield of improved varieties Yields of improved varieties Lori Niébé and CRSP Niébé in station trials are documented by Kitch et al. (1998) and Purdue/IRAD (1997). In these on-station trials, Lori Niébé and CRSP Niébé were statistically significantly different from a commonly used variety at the 5% level. In general, improved varieties yield less in farmers’ fields than under the almost ideal conditions of the research station. The on-farm yield was estimated at 80% of the station yield. This results in a simple average yield improvement of 0.02 t/ha or about 2%. These data suggest that the main benefit of the new varieties is the storage pest resistance, not increased yield. Improved yield always comes at some cost, even if that cost is difficult to calculate. Increase in seed cost due to the introduction of these varieties will probably be negligible. These are varieties and once farmers have the variety, they can easily save their own seed or get from friends and relatives. Increased yields remove more nutrients from the soil, but in northern Cameroon, farmers rarely plant cowpea with fertilizer. In the long run, a greater need for fertilizer should be expected from increased yield, but in the variety extension period of 2000–2015 it is unlikely that there will be a major move in that direction. Increased yield requires more labor and even if that is family labor it has an opportunity cost. Abdoulaye (1995) estimates that the harvest rate is about 28 kg/day in Niger. With an eight-hour day and a cost of 100 FCFA/hour, this is an added cost of about 29 FCFA/kg. Opportunity cost of capital Opportunity cost of capital in West Africa can be very high compared to levels in industrialized countries, often rising to over 100% annually for small-scale informal sector enterprises (Vijverberg 1991; Lowenberg-DeBoer et al. 1994). Lowenberg-DeBoer (1994) presents case study evidence that female cowpea street food vendors earn these high returns on their very limited capital. One hypothesis is that opportunity costs of capital are highest for low resource people with very little capital and drop as capital levels increase. The economic logic suggests that very poor people will seek out the higher return activities for their very limited capital. As they acquire more money, they exhaust those high return activities and invest in somewhat lower return larger scale enterprises. As capital levels become large, the opportunity cost approaches the level in the formal sector. Calculations suggest that returns to cowpea storage vary substantially from year to year, but since 1985 they have averaged from 15 to 25% annually depending on exactly how the calculation is done. This suggests that cowpea storage is an activity undertaken by those with relatively large amounts of capital, not the poor, and may explain why a large part of cowpea storage is handled by merchants in Maroua. As a conservative estimate of the opportunity cost of capital, the average real cost of formal sector capital in Cameroon (15% annually) was used for the parameter “r” in equation 1. A sensitivity test was done with the 50% annual cost of capital suggested by Lowenberg-DeBoer et al. (1994). It should be noted that the opportunity cost of capital in the model is defined on a six-month basis, so in the baseline analysis r = 0.15/2 = 0.075. For the NPV calculation, the real cost of long-term capital to the principal donor, the US government, was used. It was estimated as the real interest rate of 4.22% on long-term US government bonds from 1985 to 1998. 417
Page 1 and 2: Impact of cowpea breeding and stora
Page 9: Impact of cowpea breeding and stora
Page 17: Impact of cowpea breeding and stora

Impact of cowpea breeding and storage research in Cameroon - IITA

Create successful ePaper yourself

Delete template?

Save as template?