Evaluation of the Impacts of Fall Sowing Dates on Different Ecotypes of Cumin (Cuminum cyminum, Apiaceae L.) Productivity in Northeast of Iran

Abstract

Locally adapted plants can be considered as an alternative to commercial crops for cultivation in harsh environments within semi-arid regions. Nowadays, exploring these plants industrial benefits has motivated many farmers around the world to extend their cultivation. However, agronomic characters of these forgotten plants are still unknown. The main aim of this study was to evaluate the influence of fall sowing dates on yield and yield components of different Cumin (Cuminum cyminum L., Apiaceae) ecotypes in the semi-arid region of Khorasan Iran. An experiment of two years duration was performed using a split-plot randomized complete block design, employing sowing dates as main-plot factor, and cumin ecotypes as sub-plot factor in three replicates. Three levels of sowing dates included the following: mid October, mid November and mid December. Additonally, sub-plot treatments consisted of four local ecotypes of cumin from different regions of the Khorasan province (Gayen, Torbat, Sabzevar and Khaf). The plants’ survival percentage in field conditions, number of umbels m-2, number of seeds per umbel, thousand seed weight, biological, and seed yield were measured in this experiment. The results showed that all study parameters were influenced by different sowing dates except thousand seed weight. The third sowing date resulted in the highest biological (110 g m-2 and 94 g m-2 in 2006 and 2007) and seed yield (50 g m-2 and 55 g m-2 in 2006 and 2007). There was a significant positive correlation between average minimum temperature and biological yield of cumin across all ecotypes and years. The results showed significant difference in productivity of different ecotypes of cumin from various parts of northeast of Iran. The Gayen and Khaf ecotypes showed the highest plant survival percentage, biological and seed yield across study ecotypes under the third sowing date. In conclusion, delayed fall sowing date and appropriate cumin ecotypes are able to increase yield of this plant in northeast of Iran.