Effect of Humic Acid Spraying and Different Levels of Spend Mushroom Compost (SMC) on Morphological Characteristics and Yield of Castor Bean (Ricinus communis L.)

In recent years, healthy and sustainable production of agricultural products, especially medicinal plants, has received more attention. This research was done in order to evaluate the effect of humic acid spraying and different levels of spend mushroom compost (SMC) on growth and yield of castor bean (Ricinus communis L.).

In this research a split plots experiment based on RCBD design with three replications was conducted in 2015-2016 growing seasons, in University of Gonabad, Iran. The main plots included Humic acid (application and non-application) and the sub plots contained different levels of spend mushroom compost (0, 20, 40, 60, 80 and 100 t.ha-1).

The results showed that effect of humic acid spraying, different levels of SMC and their interaction effects was significant on the most of studied traits. Effect of all different levels of SMC on seed yield in conditions of humic acid spraying was exacerbated, so that seed yield in simultaneous application of humic acid and 20, 40, 60, 80 and 100 t.ha-1 levels of SMC, 40, 46, 37, 19 and 17% was more than sole application of this fertilizer, respectively. The highest and lowest height of lowest and highest panicle from ground level, obtained in treatment of simultaneous application of humic acid and 80t.ha-1 SMC and treatment of non application of humic acid and non application of SMC, respectively.

According to the results of this research, it seems application of ecological inputs such as humic acid and optimum amounts of SMC while improve growth and yield of castor medicinal plant, as an ecofriendly approach for development of sustainable agriculture and ecosystem health can be considered.