MATERNAL EFFECTS ON Lithospermum arvense L. SEED DORMANCY II. SOIL NITROGEN SUPPLY

MARÍA DE LAS MERCEDES LONGÁS; GUILLERMO RUBÉN CHANTRE; MARIO RICARDO SABBATINI

Buenos Aires

Congreso; XXII Congreso Latinoamericano de Malezas ALAM y I Congreso Argentino de Malezas ASACIM; 2015

ASACIM-ALAM

Seed dormancy is a crucial adaptative ecological trait of weeds life cycle. Primary dormancy is determined during seed development and maturation on the mother plants being influenced by environmental and management conditions, such as soil nutrients availability. Maternal effects contribute to the ecological adaptation strategy of weeds in agroecosystems which are subjected to continuous human intervention. Lithospermum arvense L. is a weedy annual species of winter cereal crops of the semiarid temperate region Argentina. This work aims to study the effect of soil nitrogen supply as a maternal factor on the level of primary dormancy of the progeny. A nitrogen gradient (0, 75 and 150 Kg N/ha) was applied on mother plants and their progeny was evaluated over a range of temperatures at different after-ripening times. A thermal-time approach based on after-ripening thermal-time accumulation was used to evaluate seed germinability as a function of the applied nitrogen level. A higher mean maximum germination temperature (Tc(50)) was observed at increasing nitrogen levels. It is suggested that primary dormancy level of L. arvense would be influenced by nitrogen fertilization of adult plants affecting the pattern of emergence under field environmental conditions.