Evaluation of saffron (Crocus sativus L.) production in Italy : effects of the age of saffron fields and plant density.

In order to establish profitable saffron (Crocus sativus L.) crops in the Mediterranean countries, information on cultural management factors such as the lifespan and the optimal plant density is needed. Two experiments were conducted, one for four consecutive years 2003-2006 (Experiment 1) and another in 2004 (Experiment 2) at the experimental station of ARSIAL located in Alvito (Frosinone), central Italy, to investigate the effect of the age of saffron fields (one, two, three or four years) and the influence of plant density (three low density (P1 76, P2 91 and P3 93 corms m -2 ), three medium density (P4 111, P5 114 and P6 119 corms m-2) and three high density (P7 139, P8 143 and P9 179 corms m-2)) on the productivity of saffron under open-field conditions. The saffron grew, flowered and produced successfully when the two-year crop cycle was adopted, whereas in the three-year treatment the spice yield was lower and declined drastically after four years. Yields of saffron recorded in the current experiment were 7.2, 15.2, 11.3 and 3.3 kg ha -1 for the one-, two-, three- and four-year cycle treatments, respectively. The number of flowers per square metre observed in the two- and three-year treatments (avg. 370) was significantly higher by 112% and 174% in comparison with the number of flowers recorded in the annual and four-year treatments, respectively. The highest dry spice was observed in the two medium (P4 and P6) and the three high density treatments (P7, P8 and P9), followed by the P5 treatment, while the lowest dry spice was recorded in the low density treatments (P1, P2 and especially P3). The number of flowers per square metre observed in the high density treatments (avg. 218) was significantly higher by 10% and 28% in comparison with the number of flowers recorded in the medium and low density, respectively. Unless corms can be purchased at markedly lower prices, farmers are recommended to plant corms at medium density due to the similar spice yield and the highest daughter corms produced in comparison with high density treatments. The results show that in a Mediterranean environment appropriate crop techniques (e.g. lifespan and plant density) can improve the quantitative characteristics of saffron.