Communal vegetable production is a key activity in Zimbabwe, contributing significantly towards food security and rural development. A study carried out in Chinamhora District determined factors influencing tomato market channel choices. Primary data were collected through formal interviews and questionnaires included household and production characteristics, markets information and social capital. Interviews with buyers provided information on prices and farmer-market relations. The logistic model was used to analyse determinants of market choices. The study revealed that informal markets are more accessible than formal markets and produce price was the major determinant of market channel choice. Thus, informal markets offer great prospects for the development of communal farmers. The study recommended that farmers should develop effective mechanisms for collaboration and linkages and invest in market intelligence for them to improve their livelihoods.

The research was carried out at Chaminuka Training Centre in Mt Darwin district of Zimbabwe. Maize producers in the rural areas are challenged by storage pests particularly the Sitophilus zeamais. Affordable and readily available protectants are needed. A common weed, Tagetes minuta, was assessed for its potential to control Sitophilus zeamais. This provides a sustainable and degradable pesticide to the poor farmers. Maize grain samples arranged in a complete randomized design (CRD) were infected with 32 weevils each. The research was run for 8 weeks with the objectives to determine the efficacy of varying forms of Tagetes minuta on Sitophilus zeamais and to establish the effect of Tagetes minuta on maize grain weight loss. Weevil counts were taken on fortnight bases to establish mortalities. Grain weight loss was assessed using the Thousand Grain Method (T G M). There were variations on treatments with varied forms. The ground Tagetes minuta had the highest effect on both weight loss and weevil mortality compared to un-ground Tagetes minuta (p = 0.001). It was concluded that the ground Tagetes minuta works through a wider spectrum by causing physical and physiological effects on the weevil resulting in mortalities.

Cotton is an important cash crop and a means of survival for Zimbabwe's smallholder farmers who are located in the semi-arid areas. However, it is plagued by a wide variety of pests. The cotton industry in Zimbabwe came up with sustainable pest management strategies which include within the season rotation of bollworm pesticides, a closed season and acaricide rotation scheme. The land reform programme brought new players in the cotton industry and it was critical to determine their knowledge on the pest management strategies. A survey was conducted to determine farmer knowledge, practice and perception on the resistance management strategy. Responses indicated that both communal and new farmers based their spray on egg counts. Communal farmers knew when to use pyrethroids compared to new farmers. Farmers observed the acaricide rotation scheme although they use some non acaricide pesticides. More than half of the new farmers could not say which acaricides were in the acaricide scheme. The majority of the farmers reported that they adhered to the closed season although field observation revealed otherwise. A significantly higher number of new farmers knew when to slash cotton compared to communal farmers. Knowledge of acaricides was not common among farmers. Use of pyrethroids was not limited to 1 February onwards as stipulated in the cotton pest resistance management strategy. The results suggest the need for training among the cotton farmers especially the new farmers or refresher courses among the communal farmers.

The influence of conservation agriculture (CA) on weed ecology has been a concern to many researchers across the world and is the focus of this study in southern Africa. An experiment to look at the impacts of various tillage systems with different levels of crop residue on maize (Zea mays L.) was established in 2004/2005 season. The experiment was carried out at the International Crop Research Institute for the Semi-Arid Tropics (ICRISAT), Matopos Research Station, Zimbabwe. Three main tillage systems were compared, ripping tillage (RT), planting basins (PB) and conventional tillage (CT), with three different crop residue levels: 0, 4 and 8 tons ha 71 . In 2007 soil samples were collected in the inter-row and in-row positions prior to tillage at 0-50 mm, 50-100 mm and 100-200 mm depths. The objective was to determine the effect of the treatment factors on weed seed bank species after three cropping cycles using the germination method. Nine major weed species were identified, with all the weeds unaffected by either tillage or mulching level. Eleusine indica, Corchorus tridens and Setaria species were the dominant weed species across all treatments. Setaria spp. was the dominant weed in the inter-row position of ripped plots. Although there was no significant individual treatment effect, there were significant (p 5 0.05) interactions, with CT having reduced seed banks of Setaria spp. and E. indica compared to RT and PB. Percentage increases point to E. indica and Setaria spp. increasing under PB and RT compared to CT. C. tridens was significantly higher in PB compared to RT and CT in the 0-50 mm depth in the in-row position. This study probably coincided with the transition period in the weed bank succession process and needs to be repeated at a later date in the rotation. The majority of the weed species were not affected by any of the treatment combinations, a response attributed to plasticity of weeds to the tillage and residue level selection pressure.

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