Effects of plant dendity on flower and essential oil yield and some important agronomic indices in Borage (Borago officinalis L.)

In order to evaluate the effects of plant dendity on flower and essential oil yield and some important agronomic indices in Borage (Borago officinalis L.) under climatic condition of Guilan province, this experiment was performed based on randomized complete block design with three replications, at Shalman research station of agricultural and natural resource research center of Guilan province, Iran, in 2013. Plant dencities includings of 20, 40, 60, 80 100 plant per m2 comprised the experimental factors. The results showed that effect of plant densities were significant for flower yield, essential oil, seed and oil yield. The greatest flower yield (based on dry meight) and essential oil content of Borago officinalis, were obtained from 40 plants per m2 density. But, the lowest essential oil content was observed at 100 plants per m2 density. In addition, the results showed that the greatest seed oil content and oil yield of Borago officinalis obtained from 40 plants per m2 density. In general, measured traits of Borago officinalis decreased due to enhancement of plant density per unit area. Thus, the density of 40 plants per m2 could be recommendable in order to increase borage productions under Guilan province and similar climatic conditions.