Small Organic Farming: The Case of Pepper (Piper Nigrum L.) Value Chain in São Tomé and Príncipe (Published)
Organic agriculture, in addition to supporting environmental sustainability, has been a meaningful way to protect and develop small farming in developing regions. The changes that have occurred within the value chain, such as increases in global standards and the effect of globalisation, have created an increase in both opportunities and risks for smallholders. In the developing countries, mainly on African continent organic agriculture beyond being less researched than in the developed ones, there are constraints related to scale, certification policies, strategies, and the fact that most farmers remain in informal circuits. This paper presents a study of the pepper value chain in São Tomé e Príncipe, which is divided into two categories: certified organic producers, affiliated (Aff) to the Cooperative of Pepper and Vanilla Export (CEPIBA) and non-certified organic pepper, non-affiliated farmers (Naf). The study presents the strategy to promote organic farming through the value chain and a brief comparison among certified and non-certified organic producers. The results showed that Aff perform better than Naf because they have financial stability and apply sustainable practices that are more productive and provide better income, while Naf generally practice subsistence farming with the exception of some medium enterprises.
Effect of Supplementary Cyan Light to Deep Red and Royal Blue Range Wavelength on the Cultivation of TAMARA F1 Pepper (Published)
This research was conducted to investigate effect of supplementary Cyan Light on growth characteristics of pepper. Three different light sources, cyan (500 nm), red (660 nm), royal blue (440 nm), in closed environmental condition are examined. For this purpose, a 3-section shelf was prepared including Tamara F1 type pepper seeds. Temperature, water, pH, electrical conductivity (EC), fertilizer and nutrient contents were controlled at requested value. First section was lighted 18 hours a day with composing 55% deep red, %25 royal blue and 20% cyan lights. Second section was lighted same hours with first section and, and second section was composed the 65% deep red and 35% royal blue lights. Same photosynthetic photon flux density (PPFD) of 360 µmol m-2s-1 was used at first and second section. The third section was lighted with sunlight in order to make a comparison with natural lighting. The experiment continued to the 55 days from seeding to harvest time. The experiment showed that; additional cyan effected on 28% more size (followed with fruit length) and 191% fruit weight. Also, there is no significant effect on plant trunk thickness and fruit number.
In this paper, the antioxidant activities of black and white pepper (Piper nigrum L.) essential oils (BEO and WEO) were evaluated and compared based on radical scavenging activities, reducing power, and DNA oxidative damage protection assays. The results showed that EOS exhibited antioxidant activities, and DNA damage protective effect to various extents. For BEO and WEO, they showed a concentration-dependent antioxidant activity at some concentrations. On the whole, WEO exhibited higher antioxidant activity than BEO. These results suggest that the essential oil of white pepper and black pepper may be a new potential source as a natural antioxidant.