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311.
Information and communication technologies (ICTs) have been shown to be useful in agricultural knowledge systems to improve communication linkages among research, extension services, and farmers. The end result would be new information and technologies being made available to those who need it the most in larger numbers and in a timelier manner. While the role of ICTs in stimulating technological, organizational, institutional, and policy innovations in developing countries has been recognized, in many Caribbean States where ICTs are becoming readily available, the development and use of ICT in agricultural research and innovation systems remain underexploited, despite the fact that the agricultural sector in these developing nations accounts for a significant amount of the total employed labor force. This article traces key developments in ICT use in the agricultural sector in the Caribbean region, while highlighting the challenges as well as the potential of this technology. Several initiatives in the region are described and suggestions made for the development of innovative, appropriate, and efficient information and communication systems.  相似文献   
312.
From 2014 through 2016, on-farm experiments were carried out in three provinces surrounding Bujumbura town in Burundi to improve the low potato (Solanum tuberosum) yields, which currently stand at about 6 t ha?1. It was hypothesised that in rain-fed conditions, improved varieties, healthier seed tubers, pre-sprouting in light, proper fertilisation and protection from late blight attack would improve yield and quality, such as tuber weight, tuber size and lower brown rot incidence. The treatments in the on-farm trials at five farms in each of three sites (15 replicates) were applied in two seasons, giving 30 replicates in 580 plots. The following treatments were compared with growers’ current practices: introduction of two new varieties, use of early generation seed from a rapid multiplication scheme, earlier harvesting of a seed crop, seed storage in a diffused light store, and research-based timing and dose rate of fertilisers and fungicides. Marginal rates of return on investments were calculated at farm level and current and tested alternative technologies were compared. Costs and benefits of applying such techniques were calculated. An improved variety contributed up to 20% yield increase and healthier seed 80%. Early harvesting reduced yield by 30% and reduced incidence of brown rot in the current season, but increased it (from 21 to 39%) in the following season when tubers were replanted. Diffused light storage, alternating contact and systemic fungicide application, and application of chemical fertilisers resulted in 30, 50 and 60% yield increases, respectively. It was shown that it is possible to double yields and economic returns (marginal rates of return) under the growing conditions in Burundi when growers plant healthy pre-sprouted seed of a new variety and apply chemical fertilisers and fungicides.  相似文献   
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