Economics of crop protection: with particular emphasis on the productivity of pesticides on cotton and maize in Machakos and Meru Districts of Kenya
Crop losses caused by pests, diseases and weeds is known to be high all over the world especially in the developirg countries. In Kerya, cotton crop is attacked by many pests and the damage is considered serious in most of the growing areas. Maize crop too is attacked mainly by maize stalk borers. The problem in many parts of Kenya is that farmers are reluctant to use pesticides to control these pests. One of the reasons why they are unwilling to use pesticides is that they are not sure of the productivity of pesticides. The objective; of this case study is to estimate production elasticities for various inputs and then estimate the marginal value product ofpesticidss on cotton in Machakos and Meru Districts. Marginal productivity of chemical pesticides for maize in Meru District will also be estimated. Another objective of the study is to find out whether the productivity of pesticides on cotton in Machakos will differ from the productivity of pesticides on cotton in Meru District. The two Districts have different average rainfall. In addition to productivity. the study will try to.find out whether there is a si[nificant difference between the yield per hectare of maize sprayed with pssticides and the yield per hectare of maize sprayed with pesticides in Meru District. Literature review revealed that there is very little hardwork done on the productivity of pesticides in Africa. The study was carriea out at Mbiuni location in Machakos District and Lower Abothuguchi location in Meru District. Secondary data collected by the Ministry of Agriculture were used. A. large sample of farmers was used and these farmers were participating in the Integrated Agricultural Development programme which w es initiated in 1976/77 for development of small scale farmers. The farmers get credit facilities for the inouts supplied to them and pay back after harvest. Supply of inputs and payment of loans is done through local co-operative societies. The data used, covered the long rain season of 1977. Analysis of the data was done using a Cobb Douglas response function and a regression analysis was carried out. Ihe dependent variable for cotton and maize was yield in kilogram. The independent variables used v:ere: (1) land in hectares. (ii) expenditure on p8stiCidos in Kenya shillings. (iii) weeding labour in man-days. (iv) other labour in man-days, (v) quantity of seeds in xix - Kg .• (vi) expenditure on fertilizers in Kenya shillings. Results showed that chemical pesticides had a positive marbinal value product especially on cotton at average farm level. In Machakos District. the rarginal value product of pesticides on cotton was K.Shs 1.05 and in Meru District it was K.Shs 1.53 per one Kenya Shilling. The marginal value product of pesticides on maize in Meru District was K.Shs 3.63 per one Kenya Shilling. More research. however, is needed on the productivity of pesticides on maize.