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A 2-year field experiment was conducted in 2012 and 2013 at the research fields of CSIR-Crops Research Institute to determine the best agronomic practices for the field establishment and cultivation of Chia (Salvia hispanica) and determine insect pests and diseases associated with the plant. The study also determined the nutritional composition of the plant under Ghanaian environment. A split-plot field trial with 2 planting methods (direct planting with seed; planting from seedling) as main plot and 3 planting density (10,000 plants/ha; 20,000 plantst/ha; 40,000 plantst/ha) as subplot were used for the agronomic evaluation of the plant. A sweep net was used to sweep diagonally across the field under two separate regimes to collect insects on the crop for the entomological investigations. Major insects collected were coreid bugs, lagria sp., Zonocerus variegatus and Diopsis thoracica. The method used for the pathological investigations were the moist blotter test and culture of pathogens on Potato Dextrose Agar. The results of the study in both years show high biomass and seed yield of chia when the crop was planted directly in the field. Narrow-row spacing of 0.5m x 0.5m consistently produced the highest biomass and seed yield in both years of the study. The results indicated that interaction between planting method and planting density positively influenced most of the growth and yield parameters of Chia plants. Nutritional profile analysis from the Chia seeds shows medium to high proximate and mineral composition. Disease evaluation revealed evidence of Fusarium wilt infection on Salvia hispanica in the field. The study recommends the adoption of direct planting method and narrow-row spacing (0.5m x 0.5m) (SP3) as the best option for the production of Chia plants in Ghana.

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Global pesticides use is increasing with environmental contamination and consumer concerns over food safety reflecting this trend. A random sampling technique using a structured questionnaire was used to select 108 cabbage farmers in Ghana and were personally interviewed. The study found that most farmers had no formal education or were educated only to primary level so had limited capacity to read and understand labels of pesticides. Whilst biopesticides were popular, about 45% of the growers use synthetic insecticides in controlling pests such as diamondback moth, cabbage aphids, cabbage white butterfly, cabbage web worm and whitefly. Forty-four percent of growers do not adhere to use of the recommended rates of insecticides, because they fail to control pests effectively. Growers with formal education were more likely to adhere to the recommended application rates of pesticides. Respondents with training in agriculture, as opposed to formal education, tended not to adhere to recommended application rates. Overall, seventyseven percent of growers did not wear any personal protective gear during chemical application and 39% had experienced at least a symptom of pesticide poisoning. Over 75% of respondents dispose of empty pesticides containers on the farm and 11% harvest their cabbage within one week after application of insecticides. Results suggest significant risks to farmers, consumers and the environment. It is expected that persistent education on the safe use of pesticides will lead to positive change in attitude of farmers.

The presence of large colonies of aphids is associated with a devastating novel necrotic disease of cabbage (Brassica oleracea var. capitata) in Ghana that is thought to be of viral etiology. In this study, we used molecular taxonomic tools to identify the aphid species present on these diseased cabbage plants. This was confirmed using two key features for morphological identification, involving the length of cornicles and shape of cauda for the wingless forms of the aphids. Two species of aphids were identified and their distribution in Ghana indicated. One was the generalist aphid Myzus persicae (Sulzer) (Hemiptera: Aphididae) but the most abundant was the brassica specialist aphid, Lipaphis erysimi pseudobrassicae (Davis) (Hemiptera: Aphididae), which is one of the most destructive pests of brassica crops in some countries in Africa and other parts of the world. L. erysimi has been reported in Benin, Mali, South Africa, India, China, and United States, but this is the first formal report of L. erysimi pseudobrassicae in Ghana. The correct identification of L. erysimi is crucial, suggesting that it has recently become one of the most common species of aphid found on cabbage plants in Ghana.