Effect of planting date and plant density on qualitative characteristics, yield and yield components of guar Cyamopsis tetragonoloba (L.) Taub. in Guilan province

In order to investigation the effect of planting date and plant density on some quantitative and qualitative traits, yield and yield components of Guar in Guilan province, an experiment was conducted in a factorial experiment in a randomized complete block design with three replications in a research station of Rice Research Institute located in Gilpardesar village at Sangar in 2017. Experimental treatments included Planting dates at four levels (12 May, 26 May, 9 June, 23 June) and plant density at three levels (20, 40 and 60 plant.m-2). Results showed to delay in planting date from 26 May to 23 June, protein percentage, galactomannan percentage, plant height, dry weight at flowering stage, Number pods per plant, 100 seed weight, seed yield and biological yield were decreased 42.55%, 45.09%, 25.26%, 62.42%, 62.72%, 13.82%, 77.14% and 58.96%, respectively. The highest of seed yield (6987.25 Kg.ha-1), protein (28.2%) and galactomanan (27.5%) was obtained from 26 May sowing date and plant density of 40 plant.m-2. The above traits also increased with increasing in density from 20 to 40 plant.m-2. But a further increase in density to 60 plant.m-2 resulted in a decrease in these traits. Carbohydrate also increased with delay in planting. The number of seeds per pod and fat percentage was not affected by different planting dates and densities. The results also showed to delay in planting reduced the length of the growing season. The results of the present study indicate that proper planting date and plant density play an important role in yield enhancement and quality characteristics of guar seed and planting date of 26 May and density of 40 plant.m-2, due to longer growing season and appropriate climatic conditions. In addition, pod yield and seed weight, were higher seed yield than other treatments.