Morphological and yield responses of Silybum marianum L. to chemical and biological fertilizers in different planting dates

Medicinal crops production is well interested in Iran due to market demand in recent years. Silybum marianum L. is an annual or biennial plant, native to the Mediterranean region, which now could be found in other warm and dry regions. Silybium marianum is used traditionally as a hepatoprotective agent and supportive treatment of liver disorders (Abdolahzareh et al., 2012). Management of planting date and integrated nutrition systems in medicinal plantsIntroduction other in found be could now which, region Mediterranean the to native, plant biennial or annual an is. L marianum treatment supportive and agent hepatoprotective a as traditionally used is marianum Silybium. regions dry and warm constitute main the is silybin which, silymarin, compounds flavonolignan contain fruits Its. disorders liver of have plants medicinal in systems nutrition integrated and date planting of Management). 2012., al et Abdolahzareh( In. period growth the in parameters weather changing through yields crop the affects date Sowing. considered be to and continuous Today. production crop on influence an has, type and rate fertilizers, date planting to addition causing environment and health soil on impacts negative have may fertilizers chemical of application excessive sustainable as considered are fertilizers-Bio). 2017., al et Vashvaei Mohammadpour (problems environmental to was study present the of objective The. fertilizers synthesized the to compared nutrients of sources alternative morphological the on) integrated and biological, chemical (system fertilizing and date sowing of effects the examine .conditions Iran, Birjand under thistle milk the of yield and traits Azad Islamic, branch Birjand of farm research the at out carried was.

research This: complete randomized a on based plot split a as conducted was experiment The. 2018 in, Iran, Birjand, University systems fertilizing 6 and) 5 May and 4 April, 6 March (dates sowing Three. replications three with design blocks (Akadin% 50 + NPK% 50, vermicompost% 50 + NPK% 50, Akadin, vermicompost, NPK, control as fertilizer-non( of yield and traits morphological some of responses the study the In. respectively plots sub and plots main as were cm/mmos 3.2 and 4.7 were EC and pH Soil. loam was study of site the in texture Soil. evaluated were Thistle Milk ,cm 30-0 of depth the at kg/mg 2.75 and 6.11, 8.3 were soil the of content K and, P, Nitrogen. respectively .level% 5 at Test LSD by compared were means and software statistical SAS by analyzed were data All. respectively plant (traits morphological average highest the had) 6 March (date planting first The: discussion and Results m2 per number capitol (components yield seed and) branches of number and diameter capitol, height seed of number, vermicompost% 50 and NPK% 50 treatments the hands other the On). yield seed, weight seed-1000, capitol per 4.318 (lowest the and) ha/kg 7.3327 (highest The. traits studied the of most for superiority statistical had fertilizers of date planting the for declining yield seed that seems It. respectively, date planting third the at application fertilizernon of treatment and date planting first the at vermicompost+ NPK treatments the to related were yield seed) ha/kg This. heating summer with pollination of coincidence the and season growth of shortening the to related was, 5 May m2 per capitol of number the in decrease severe a caused organic using, Normally. capitol per seed of number the and the in activity microorganisms increases; soil the of aspects physical improves fertilizers chemical with fertilizers et Vashvaei Mohammadpour (yield seed eventually and components yield, photosynthesis, availability nutrients, soil positively quantity traits Morphological). 2019. (al et Zarghani by reported been have also results Similar). 2017., al first the for observed were traits these for value highest the Thus. yield seed and components yield to correlated this in marianum Silybum of yield seed of superiority the, result a As. vermicompost+ NPK using under date planting traits that showed analysis regression of results The. expected be to was, treatments other to compared treatment m2 per capitol of number, diameter capitol the into entered were weight seed-1000 and capitol per seed of number, .changes yield seed total of% 57.84 explained which, model regression planting this and dates planting two other the to superior was 6 March of date planting the, general In.

using under region Birjand in. L marianum Silybum of cultivation the for date suitable a as suggested be could date .vermicompost% 50+ NPK% 5 have to be considered. Sowing date affects the crop yields through changing weather parameters in the growth period. In addition to planting date, fertilizers rate and type, has an influence on crop production. Today continuous and excessive application of chemical fertilizers may have negative impacts on soil health and environment causing environmental problems (Mohammadpour Vashvaei et al., 2017). Bio-fertilizers are considered as sustainable alternative sources of nutrients compared to the synthesized fertilizers. The objective of the present study was to examine the effects of sowing date and fertilizing system (chemical, biological and integrated) on the morphological traits and yield of the milk thistle under Birjand, Iran conditions. Materials and Methods This research was carried out at the research farm of Birjand branch, Islamic Azad University, Birjand, Iran, in 2018. The experiment was conducted as a split plot based on a randomized complete blocks design with three replications. Three sowing dates (March 6, April 4 and May 5) and 6 fertilizing systems (non-fertilizer as control, NPK, vermicompost, Akadin, 50% NPK + 50% vermicompost, 50% NPK + 50% Akadin) were as main plots and sub plots respectively. In the study the responses of some morphological traits and yield of Milk Thistle were evaluated. Soil texture in the site of study was loam. Soil pH and EC were 7.4 and 2.3 mmos/cm respectively. Nitrogen, P, and K content of the soil were 3.8, 11.6 and 75.2 mg/kg at the depth of 0-30 cm, respectively. All data were analyzed by SAS statistical software and means were compared by LSD Test at 5% level.

The first planting date (March 6) had the highest average morphological traits (plant height, capitol diameter and number of branches) and seed yield components (capitol number per m2, number of seed per capitol, 1000-seed weight, seed yield). On the other hands the treatments 50% NPK and 50% vermicompost fertilizers had statistical superiority for most of the studied traits. The highest (3327.7 kg/ha) and the lowest (318.4 kg/ha) seed yield were related to the treatments NPK+ vermicompost at the first planting date and treatment of non-fertilizer application at the third planting date, respectively. It seems that seed yield declining for the planting date of May 5, was related to the shortening of growth season and the coincidence of pollination with summer heating. This caused a severe decrease in the number of capitol per m2 and the number of seed per capitol. Normally, using organic fertilizers with chemical fertilizers improves physical aspects of the soil; increases microorganisms activity in the soil, nutrients availability, photosynthesis, yield components and eventually seed yield (Mohammadpour Vashvaei et al., 2017). Similar results also have been reported by Zarghani et al. (2019). Morphological traits quantity positively correlated to yield components and seed yield. Thus the highest value for these traits were observed for the first planting date under using NPK+ vermicompost. As a result, the superiority of seed yield of Silybum marianum in this treatment compared to other treatments, was to be expected. The results of regression analysis showed that traits capitol diameter, number of capitol per m2, number of seed per capitol and 1000-seed weight were entered into the regression model, which explained 84.57% of total seed yield changes. Conclusions In general, the planting date of March 6 was superior to the other two planting dates and this planting date could