This paper studies the introduction of new varieties of goods in the Chinese manufacturing sector during the period 1998-2000. I first develop a monopolistic competition model with multiproduct firms in which firms are heterogeneous in two dimensions: the fixed cost of introducing varieties into the market and the variable cost of production. Using firm-level data for the Chinese manufacturing ...

BACKGROUND Artificial selection results in phenotypic evolution. Maize (Zea mays L. ssp. mays) was domesticated from its wild progenitor teosinte (Zea mays subspecies parviglumis) through a single domestication event in southern Mexico between 6000 and 9000 years ago. This domestication event resulted in the original maize landrace varieties. The landraces provided the genetic material for mode...

Morpho-physiological response of 7 rice (Oryza sativa L.) varieties viz., Moroberekan, Co39, Azucena, Bala, IR64, Kalinga-III and Nipponbare was assessed under control and 100 mol m NaCl + 5 mol m CaCl2 stress in a flood bench system in greenhouse. Physiological and growth parameters were recorded after 21 or 42 days of salt stress. The statistical analysis revealed significant differences amon...

Knowledge of genetic diversity (GD) and relationships among maize inbred lines is indispensable in a breeding program. Our objectives were to (1) investigate the level of genetic diversity among maize inbred lines and (2) assess their genetic structures by applying simple sequence repeat (SSR) markers. Fifty-six highland and mid-altitude maize inbred lines obtained from CIMMYT programs in Ethio...