Evaluation of planting patterns and fertilizer treatments on growth and flower and seed yield of mallow (Malva sylvestris L.) as a medicinal plant

Under limited moisture conditions, various row planting arrangements have been utilized to provide additional moisture for plant growth and development. Planting patterns had significant effects on the availability of water in time to better match crop development.Soil fertility is one of the most important factors in agricultural operations. Also, soil fertility greatly contributes to yield differences for the same agronomic practices. It is well-known from numerous fertilizer experiments that mallow yield is strongly dependent on the supply of organic matter and mineral nutrients. Cow manure and municipal waste compost in controlling different types of debris and the reduction in fertilizer consumption in agricultural products and mineral absorption elements improve low consumption by plants. Mallow (Malva sylvestris) (Malvaceae) is a medicinal plant that it was used for its emollient and laxative properties and is a popular medicine. Mallow broadly used for various inflammatory conditions (Wichtl, 2004). Phytochemical studies of this plant revealed the presence of numerous polysaccharides, anthocyanins, coumarins, tannins, flavones, flavonols, anthocyanidins, leucoanthocyanidines, mucilagen and essential oil (Unver et al., 2009). Therefore, the objectives of the current study are to evaluate the effects of planting pattern and fertilizer treatments on growth, flower and seed yield of mallow as a medicinal plant.

A field experiment was conducted as a split-plot based on a complete randomized block design with three replications at Faculty of Agriculture, Ferdowsi University of Mashhad during two growing seasons of 2012-2013 and 2013-2014. Fertilizer sources of cow manure (40 t.ha-1), municipal waste compost (20 t.ha-1), chemical fertilizer and control (without fertilizer), three planting patterns included 70 cm apart single side row, 90 cm apart single side row and two side rows and two harvests were the main, sub and subfactors, respectively. After land preparation, organic fertilizers were added to the soil. Based on nutrient contents in organic fertilizers, N, P and K for chemical fertilizers were determined by 114, 18 and 220 kg.ha-1. P (as triple superphosphate) and K (potassium sulfate) were applied just before sowing. Urea (N fertilizer) was applied as a top dressing in three stages such as sowing, thinning and flowering stages when the crop was irrigated.Plant height, the fresh yield of flower, the dry yield of flower, biological yield, seed yield and mucilage content of mallow were measured. To analyze the variance of the experimental data and drawing of diagrams, MSTAT-C and Excel software was used. All the averages were compared according to Duncan’s multiple range test (p≤0.05).

The results showed that the simple and interaction effects were significant on most studied traits. The highest dry yield of the flower was observed in the interaction of manure+ two side rows (4071.17 kg.ha-1) and the lowest was for control+90 cm apart single row (1095.85 kg.ha-1). The maximum and the minimum dry yield of the flower were observed in manure in the second harvest (4596.06 kg.ha-1) and for control in the first harvest (941.69 kg.ha-1) treatment, respectively. The highest biological yield and seed yield were obtained in two side rows (4731.01 and 813.60 kg.ha-1) and the lowest was for 90 cm apart single row (with 3880.96 and 635.74 kg.ha-1), respectively. Manure affected mucilage percent significantly, (12.06%) and the lowest was for chemical fertilizer (9.32%).

Manure increased nutrient uptake by plants, improving plant hormone-like activity, increase soil water holding capacity, and generally improve the growth and yield of medicinal plant. It can be concluded that two side rows and cow manure could be considered as a suitable treatment for improving quantity and quality yield of this medicinal plant.