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В данной обзорной статье представлена информация о генах диких видов растений, которые были перенесены в сельскохозяйственные культуры в ходе селекционного процесса за последние 20 лет. За эти годы наблюдалось стабильное увеличение количества новых сортов, содержащих генетический материал диких видов, а также расширился диапазон характеристик тех генов, которые вводятся в культурные сорта. Те сельскохозяйственные культуры (пшеница, томат), чьи дикорастущие сородичи традиционно использовались как источники ценных признаков, по-прежнему остаются приоритетными для переноса новых генов от их диких видов. Несмотря на то, что постоянно улучшаются технологии межвидового скрещивания, вводятся в селекционную практику молекулярные методы, пополняются коллекции в генбанках и все больше публикуется работ с описанием наиболее значимых признаков дикорастущих видов, тем не менее, вклад дикорастущих сородичей культурных растений в усовершенствование новых сортов остается меньше, чем это можно было бы ожидать.

Cacao (Theobroma cacao L.) is indigenous to the Amazon basin, but is generally believed to have been domesticated in Mesoamerica for the production of chocolate beverage. However, cacao's distribution of genetic diversity in South America is also likely to reflect pre-Columbian human influences that were superimposed on natural processes of genetic differentiation. Here we present the results of a spatial analysis of the intra-specific diversity of cacao in Latin America, drawing on a dataset of 939 cacao trees genotypically characterized by means of 96 SSR markers. To assess continental diversity patterns we performed grid-based calculations of allelic richness, Shannon diversity and Nei gene diversity, and distinguished different spatially coherent genetic groups by means of cluster analysis. The highest levels of genetic diversity were observed in the Upper Amazon areas from southern Peru to the Ecuadorian Amazon and the border areas between Colombia, Peru and Brazil. On the assumption that the last glaciation (22,000-13,000 BP) had the greatest pre-human impact on the current distribution and diversity of cacao, we modeled the species' Pleistocene niche suitability and overlaid this with present-day diversity maps. The results suggest that cacao was already widely distributed in the Western Amazon before the onset of glaciation. During glaciations, cacao populations were likely to have been restricted to several refugia where they probably underwent genetic differentiation, resulting in a number of genetic clusters which are representative for, or closest related to, the original wild cacao populations. The analyses also suggested that genetic differentiation and geographical distribution of a number of other clusters seem to have been significantly affected by processes of human management and accompanying genetic bottlenecks. We discuss the implications of these results for future germplasm collection and in situ, on farm and ex situ conservation of cacao.

Recognized as a priority three decades ago, in situ conservation of crop wild relatives has developed theoretical and methodological focus and achieved significant on-the-ground progress in the last 10 years, most notably under the impetus of the plant genetic resources community. Literature and Internet searches and interviews with experts were undertaken as a basis for reviewing the current status and trends of this effort worldwide. Country-by-country summaries on in situ crop wild relatives conservation activities are presented, and recommendations are made for future action. Principal recommendations include ‘flagging’ of appropriate taxa as crop wild relatives in botanical and conservation databases, undertaking gap analyses to locate crop wild relatives hotspots, and enhancing cooperation between the plant genetic resources and plant conservation communities. [ABSTRACT FROM AUTHOR]