INTRODUCTION

1. NAME: ODONGO MESO HILDAREG NO: A22/0070/2009BSc AGRICULTURE (Crop Protection)SPECIAL PROJECT PROPOSAL PRESENTATION ON: THE EFFECT OF SELECTED HERBICIDES ON WEED SPECIES IN COFFEESUPERVISER: PROFESSOR RATEMO MICHIEKA

2. INTRODUCTION • Coffee is one of the world’s largest traded commodities produced in more than 60 countries, providing a livelihood for some 25,000,000 coffee farming families around the world. • The coffee sub-sector in Kenya is one of the major employers and contributed about 5% of export revenues in 2003.The national area under coffee is estimated at 170,000 hectares. Coffee is grown between altitude 1,400 and 2100 meters above sea level.

3. Problem Statement • A large number of annual and perennial weeds infest coffee plantations. Tropical climates with ample sunshine, heat and moisture mean that weeds thrive and may compete with crops for space, water and nutrients, and shade the crop plants, especially when they are young. (Friesslenben et al…1991) • Weeds significantly reduce yield, make farm operations difficult and could even be toxic to livestock, all these in turn result in economic losses. • Small scale farmers most of the time have capital constraints this translates to inappropriate use of herbicides or continous use of readily available herbicides without appropriate education on application rates, frequency of application and stage of application, All these practices could lead to a shift in weed species in coffee plantations or development of resistance to herbicides.

4. Justification • Historically, coffee has been an important commodity in Kenya because of its contribution to foreign exchange earnings, farm incomes and employment opportunities. Prior to 1988, coffee was Kenya’s leading foreign exchange earner and currently ranks fourth after tourism, tea and horticulture, accounting for 10% of the total export earnings in the year 2000 and 6% in 2001. Over 600,000 smallholders are engaged in coffee production and currently command a 48% share of the market. • Earnings from coffee are important as they increase the purchasing power of small holder farmers thus enhancing their economic status. • The study finds out to what extend weeds affect coffee production, and ways in which production can be increased through efficient weed control.

5. Objectives Overall objective • To find out the effect of long-term use of paraquat and glyphosate on weed populations in coffee Specific objective • To find out the challenges faced on the use of Paraquat and glyphosate in terms of weed shift and weed resistance, the amount farmers use and the frequency of use, time of use in terms of stage of growth on both weeds and the crop is also of importance Null Hypothesis • The long term use of paraquat and glyphosate results in a shift of weed species in coffee Alternative Hypothesis Long term use of paraquat and glyphosate has no effect on weed species in coffee.

6. Weeds as a Constraint in Coffee Production • Weeds are a serious problem in many crops including coffee both in nurseries and established orchards, a large number of perennial and annual weeds infest coffee plantations, • Weeds commonly found in coffee include

8. Common Weed Management Practices in Coffee • Shade • Hand Hoeing and Mechanical Tillage Implements • Slashing • Cover crops • Mulch • Herbicides (glyphosate, Paraquat)

9. Glyphosate • Glyphosate (N-(phosphonomethyl) glycine) is a non-selective broad-spectrum systemic post emergence herbicide that has been used extensively throughout the world over the past three decades. • It inhibits the biosynthesis of aromatic amino acids (phenylalanine, tyrosine and tryptophan) which leads to several metabolic disturbances including inhibition of protein and secondary product biosynthesis

10. Paraquat • paraquat is a quick acting herbicide that destroys green plant tissue by contact action and some translocation, it is rapidly and tightly bound to soil, it is used to control broad-leaved weeds and grasses, being less effective on deep rooted plants such as dandelions.

11. Weed shift and resistance • Shift-Refers to a change in the relative abundance or type of weeds as a result of management practices such as herbicide use, which brings about a change in weed species composition. • Resistance-changes in response to herbicide use and other management decisions. a small number of plants within a species, called a “biotype,” have a distinct genetic makeup that allows them to tolerate a particular herbicide application. Multiple weed biotypes can exist in a single field.

12. Materials and Methods • Data will be collected by means of a questionnaire administered to farmers, a sample of 30-40 farmers will be questioned in Kiambu County which is one of the major coffee producing areas in the country. • Questions to be asked include but are not limited to; • -the length of time in years that the farmer has produced coffee • -general trends in yield of coffee in the farm • -weeds present and prevalent in the farm • -methods of weed control • -herbicides used in weed control • -if there has been observed changes in weed species over time. • Data collected will be analyzed using SPSS package (Version 19).

13. Work Plan

14. Budjet

15. References • Akobundu I.O 1987 Weed science in the Tropics Principles and Practices John Whiley and Sons New York 522 pp • Coffee cocoa and tea K.C. Wilson • Coffee the Plant the Product Rene Coste • Monsanto Agricultural Company, Chesterfield, MO 63198. • Nishimoto, R.K Evaluation of Pre emergence Herbicides for Establishing Coffee • Njoroge, J.M.E, Mwakha, 1983 Observation of the Effects of Weeding and Cover Crops on Coffee Yield and Quality • Tropical Pest management, Volume 21, Issue 1, March 1975 pg 58-63 • Weed Management for Developing Countries R.Labrada, J. C. Casely