Unravelling the palaeobiogeographical history of the living fossil genus Rehderodendron (Styracaceae) with fossil and extant pollen and fruit data.

BACKGROUND: The relict genus Rehderodendron (Styracaceae), the species of which are restricted to mostly warm temperate to tropical climate in East Asia today, is known from fossil fruits and pollen in Europe during warmer periods from the lower Eocene to Pliocene. To infer which extant species are most closely related to the fossils, new data of pollen and fruit morphologiesy of six extant species, and additional new data of fossil pollen and previously described fossil fruits of Rehderodendron, are compared. RESULTS: Both fossil pollen and fruits resemble a morphological mixture of the extant species R. indochinense, R. kwantungense, R. macrocarpum, and R. microcarpum, thus implying that these extant taxa and the fossil European taxa represent an old Eurasian lineage, whereas the pollen and fruit morphology of the extant R. kweichowense and R. truongsonense differ considerably from the fossils and other extant species investigated, and are considered to have evolved independently. CONCLUSIONS: The palaeobiogeographical history of Rehderodendron reveals that its fossil members of the European lineage were most prominent during climatic optima such as the Palaeocene-Eocene Thermal Maximum (PETM), Early Eocene Climate Optimum (EECO) and Middle Miocene Thermal Maximum (MMTM). However, when during the Pliocene the climate changed to colder and less humid conditions, the genus went extinct in Europe but migrated eastwards, most likely in two dispersal events along the Tethys Sea prior to extinction. One of the former most westerly stepping stones is suggested by the refugial occurrence of R. microcarpum in the southeastern Himalaya, whereas R. macrocarpum and R. kwangtungense, the taxa distributed more to the east, might have migrated eastwards already before the Miocene.

How Could Agronomic Biofortification of Rice Be an Alternative Strategy with Higher Cost-Effectiveness for Human Iron and Zinc Deficiency in China?

BACKGROUND: Iron and zinc deficiencies affect human health globally, especially in developing countries. Agronomic biofortification, as a strategy for alleviating these issues, has been focused on small-scale field studies, and not widely applied while lacking of cost-effectiveness analysis (CEA). OBJECTIVE: We conducted the CEA of agronomic biofortification, expressed as USD per disability-adjusted life years (DALYs) saved, to recommend a cost-effectiveness strategy that can be widely applied. METHODS: The DALYs were applied to quantify the health burden due to Fe and/or Zn deficiency and health cost of agronomic biofortification via a single, dual, or triple foliar spray of Fe, Zn, and/or pesticide in 4 (northeast, central China, southeast, and southwest) major Chinese rice-based regions. RESULTS: The current health burden by Fe or Zn malnutrition was 0.45 to 1.45 or 0.14 to 0.84 million DALYs for these 4 regions. Compared to traditional rice diets, the daily Fe and/or Zn intake from Fe and/or Zn-biofortified rice increased, and the health burden of Fe and/or Zn deficiency decreased by 28% and 48%, respectively. The cost of saving 1 DALYs ranged from US$376 to US$4989, US$194 to US$2730, and US$37.6 to US$530.1 for the single, dual, and triple foliar Fe, Zn, and/or pesticide application, respectively, due to a substantial decrease in labor costs by the latter 2 applications. CONCLUSIONS: Agronomic biofortification of rice with the triple foliar spray of Fe, Zn, and pesticide is a rapidly effective and cost-effectiveness pathway to alleviate Fe and Zn deficiency for rice-based dietary populations.