Growth and yield of chia (Salvia hispanica L.) in the Mediterranean and desert climates of Chile

Chia (Salvia hispanica L.) is a species with seeds that have high essential fatty acid content, which has encouraged increased crop production worldwide. However, the expansion of chia is limited because it is a photoperiod-sensitive plant adapted to areas without cold. The objective of the present study was to determine the effect of different climatic conditions on the growth, grain yield and oil production of chia under irrigation in three geographic areas of Chile: Valle de Azapa (18 degrees 30' S lat) with a coastal desert climate, normal desert climate in Canchones (20 degrees 26' S lat), and Las Cruces (33 degrees 30' S lat) with dry Mediterranean climate with marine influence, and two chia phenotypes: white and dark. Results indicated that desert conditions in the Valle de Azapa (VA) and Canchones (CH) provided better conditions for plant growth; the highest yield (> 2900 kg ha(-1)) and oil production (> 550 L ha(-1)). In Las Cruces (LC), at higher latitude, low temperatures present beginning in April coincided with the reproductive stage, affecting yield which was no more than 129 kg ha(-1); thus this zone is not recommendable for chia cultivation. This study also determined an 11.8 h day length threshold for the beginning of flowering; when plants are exposed to shorter days flower initiation is more precocious, but when day length is not adequate plants only begin to flower when they have accumulated 600-700 degrees C d.