Сравнение методов

	Participatory Varietal Selection	On-Farm Agrobiodiversity Index
Область	Food Agriculture Studies	Food Agriculture Studies
Семейство	Process / pipeline	Process / pipeline
Год появления	1996	2008
Автор метода	John R. Witcombe and colleagues	Devra Jarvis & colleagues (on-farm crop-variety diversity framework); diversity indices after Magurran
Тип	Participatory experimental pipeline for cultivar identification	Descriptive diversity-index pipeline for cultivated and reared diversity on farms
Основополагающий источник	Witcombe, J. R., Joshi, A., Joshi, K. D., & Sthapit, B. R. (1996). Farmer Participatory Crop Improvement. I. Varietal Selection and Breeding Methods and Their Impact on Biodiversity. Experimental Agriculture, 32(4), 445-460.	Jarvis, D. I., Brown, A. H. D., Cuong, P. H., Collado-Panduro, L., Latournerie-Moreno, L., Gyawali, S., et al. (2008). A global perspective of the richness and evenness of traditional crop-variety diversity maintained by farming communities. Proceedings of the National Academy of Sciences, 105(14), 5326-5331.
Другие названия	PVS, Farmer Participatory Variety Selection, Participatory Variety Selection, Client-Oriented Varietal Selection	On-Farm Crop Diversity Index, Agrobiodiversity Index, Farm Varietal Diversity Index, Cultivated Diversity Index
Связанные	4	4
Сводка	Participatory varietal selection (PVS) is a participatory crop-improvement method in which farmers choose, grow, and evaluate finished or near-finished cultivars on their own fields under their own management, so that the varieties identified are the ones farmers actually prefer and will adopt. Formalized by John Witcombe and colleagues in 1996 as the faster, cheaper sibling of participatory plant breeding, PVS responds to the problem that conventional varietal release — selection on research stations against breeder criteria — often produces varieties that fail in farmers' fields or ignore traits farmers value, leaving the formal seed system with low adoption in marginal, heterogeneous environments. By moving the final stage of selection onto farms and into farmers' hands, PVS rapidly screens existing genetic material for fitness to real growing conditions and real preferences.	The on-farm agrobiodiversity index applies the mathematics of biological diversity — richness, evenness, and combined indices such as Shannon, Simpson and Margalef — to the crops, landraces, varieties and livestock breeds that farmers actually maintain in their fields and herds. Rather than counting wild species in an ecosystem, it quantifies cultivated and reared diversity: how many distinct crop species and varieties a farm grows, how evenly the area or production is spread across them, and how this compares between farms, communities and regions. Devra Jarvis and a large international team showed in 2008 that these measures of richness, evenness and divergence reveal substantial crop-variety diversity still maintained on farms worldwide and provide a sound basis for indicators of on-farm conservation. Built on Magurran's standard diversity formulas, the index turns agrobiodiversity into measurable, comparable numbers for research and policy.