CORM SIZE AND INCUBATION EFFECTS ON TIME TO FLOWERING AND THREADS YIELD AND QUALITY IN SAFFRON PRODUCTION IN ARGENTINA

Saffron flowering is greatly concentrated in time. In San Carlos, Mendoza, Argentina (33°44'S), 75% of flowers emerge at 7 times within a lapse of 20 days; in just 2 of these days, 50% of anthesis occurs. Due to this fact, the work intensity on the crop is extremely variable and the availability of manual labor is always challenging. The previous works of Molina et al. (2004) on saffron flowering physiology allow extending and arranging the flowering period at regular intervals, by means of incubating corms under controlled temperature conditions. The aim of this work was to verify possibilities of extending and modifying the flowering time of saffron in Argentina, evaluating the effect on flowers and saffron production of corm size and the duration of incubation under summer-like conditions (23-27°C), and comparing results from controlled environments with field crop data as well. Two categories of corm size (S3 and S4, 2.5-3.4 cm and 3.5-4.4 cm of equatorial diameter respectively), in six periods of incubation (between 59 and 101 days), were tested. Saffron quality was assessed following ISO standards. Saffron production under controlled environment was superior in yield as well as in quality to that obtained in the field. Corm size categories proven resulted of high agronomic usefulness, permitting the discrimination of production levels according to corm biomass. S4 corms were three times more productive than S3. There was a linear positive relationship between days of incubation and harvest time, allowing to forecast the flowering period and to improve the programmed use of farm facilities. Under these conditions, an earlier flowering up to 29 days was possible in relation to the field crop.