THE INFLUENCE OF THE PLANTATION ESTABLISHMENT METHOD ON THE YIELD OF MARSHMALLOW ( ALTHAEA OFFICINALIS L . )

The field experiment with one- and two-year-old marshmallow plants was carried out in Zamośc on brown soil of loess origin in 2002-2004. There were four methods of plantation establishment: 1) direct sowing in the field (control object); 2) direct sowing in the field with cover of polypropylene sheet; 3) by seedlings from a plastic house; 4) by seedlings produced in multi-cell propagation trays. It was found that, in the case of one-year-old plants, all the methods of plantation establishment significantly increased the yield and the number of marshmallow flowers, as compared to the control object, but the best results were obtained when the plants were propagated from seedlings produced in multi-cell trays. Taking into account the two-year-old plants, no significant impact of the plantation establishment method on flower yield was found. On average, total yields of flowers varied from 17.2 dt×ha -1 in the first year of vegetation to 27.8 dt×ha -1 in the case of the two-year-old plants.


INTRODUCTION
Marshmallow Althaea offi cinalis L. is a valuable medicinal plant belonging to the Malvaceae family.The roots of the plant are the most frequently used pharmaceutical raw material, but the fl owers are also significant, particularly in folk medicine.Pale pink, fi ve-petalled fl owers, up to 5 cm in diameter, grow individually or in bunches from the corners of the leaves in the upper part of the stalks.The plant fl owers in July and August, but the fl owering stage often extends until September.A single fl ower ceases to blossom quite early, after 3-4 days.That is why fl owers in blossom occur next to those that have already ceased.For medicinal purposes, fl owers are collected successively as they bloom.Proven medicinal properties are primarily attributed to the mucilage which is present in the fl owers and roots and has antitussive, softening and coating effects (H o j d e n , 1996; K o z ł o w s k i et al. 1989; S t r z e l e c k a and K a m i ń s k i , 2000).Besides the mucilage, the fl owers contain fl avonoids, the most important of which is tiliroside, a compound with a proven anti-infl ammatory effect (G u d e j , 1990).Marshmallow preparations belong to the group of agents used for the treatment of respiratory tract infections, stomatitis, pharyngitis and esophagitis as well as digestive tract disorders and metabolism disorders (B u c h w a l d and S z c z y g l e ws k a , 1999; K o z ł o w s k i , 1995).
In the literature output, research concentrates on yields of roots and there is a lack of information concerning the fl owers.The aim of this study was to determine the effect of the plantation establishment method on fl owering dynamics and fl ower yield in the fi rst and the second year of marshmallow vegetation.

MATERIALS AND METHODS
The results of the study based on a fi eld experiment done in the years 2002-2004 in Zamość on brown soil of loess origin.The soil was characterized by a medium humus and magnesium content, very high phosphorus and potassium content, and it was neutral in reaction.Mineral fertilization was applied in the following doses (kg ha -1 ): 70 N, 25 P, 90 K.The following methods of plantation establishment were compared: 1) direct sowing in the fi eld (control object); 2) direct sowing in the fi eld with cover of polypropylene sheet; 3) planting seedlings obtained in a heated plastic house (tunnel); 4) planting seedlings produced in multi-cell propagation trays (also in a plastic house).The experiment was set in a scheme of random blocks in four replications on plots of 20 m 2 each.Every year the plots were divided into 2 halves, one was used for one-year-old plants, while the other was assigned for two-year-old plants.In order to obtain seedlings (in both objects) seeds were sown in the middle of March, on a peat substrate.In the fi eld seeds were sown in mid-April.Directly after the sowing, the designated plots were covered with polypropylene sheet, which was removed when the plants reached the height of about 15 cm.The seedlings were transplanted to the fi eld at the beginning of May.The same spacing of plants, 50x40 cm, was used in all the objects.
During the vegetation period, observations of fl owering were conducted.As the plants were coming into blossom, the fl owers were colected at 2-3 day intervals (from 10 plants on each plot).The fresh weight of the fl owers was determined and the air dry weight was recorded after 2 weeks of drying (in natural conditions).The yield achieved was calculated per hectare.Furthemore, the number of fl owers produced by one plant was determined.The results were statistically analyzed with Tuckey's method and the smallest signifi cant differences were calculated.

RESULTS
The weather conditions during the research determined the course of marshmallow fl owering, especially in the fi rst year of vegetation (Tab.1).Warm and humid weather in May and June in the years 2002 and 2003 was conducive to the development of the plants, and the full fl owering stage was observed in the second half of July (except for the control object).The weather in year 2004 was less favourable.A considerable defi ciency of rainfall in late April and the 1 st half of May impeded the emergence and prolonged the seedling stage of plants, whereas low precipitation in June and July (1st and 2nd decade) delayed the fl owering stage, as compared to the other years.
Flowering of the one-year-old plants depended on the method of plantation establishment.It was found that marshmallow grown from seedlings achieved the blooming stage much earlier than the plants from direct sowing in the fi eld.Covering the plots with polypropylene shortened however the period between seed sowing and the time of full fl owering, on average by 3 days in the years 2002 and 2004 and by 8 days in 2003 (Tab.2).
In the second year of vegetation, fl owering was observed much earlier in comparison to one-year-old plants, and the full fl owering stage occurred at the beginning and mid of July, in 2003 and 2004 respectively.It was found that the plantation establishment method in the particular years did not infl uence the length of the period between the beginning of vegetation in spring and the fl owering stage.Although in 2004 the full fl owering stage was recorded on average 11-12 days later as compared to the previous year, it was caused by the delayed beginning of the spring vegetation of plants.The method of plantation establishment modifi ed the yield of marshmallow fl owers.In the fi rst year of vegetation at the beginning of the fl owering stage, a small yield was obtained, but it was gradually higher over time (Figs 1-3).In the plots where seedlings were planted, the plants produced much more fl owers in this period     The total yields of fresh and air dry mass of fl owers in the fi rst year of vegetation amounted to 86.4 dt ha -1 and 17.2 dt ha -1 , respectively.Statistically signifi cant differences in the yield were among all the experimental objects (Tab.4).Establishing the plantation from seedlings produced in multiplates was the best method in terms of fl ower generation.The plants from this object produced the largest number of fl owers, resulting in the highest yield of fresh and air dry mass of fl owers.Signifi cantly lower values of these traits were achieved when seedlings were produced in a plastic tunnel, whereas direct sowing proved to be the least effective method.
The collection of fl owers in the plantation with two-year-old plants began about two weeks earlier than in the fi rst year of vegetation (Figs 4-5).The greatest number of fl owers was obtained in the second half of July in 2003 and at the beginning of August in 2004.On average, the yields of fresh and air dry matter of fl owers were higher, as compared to one-year-old plants (by 48% and 62%, respectively), but the method of plantation establishment had no signifi cant infl uence on the yield and number of marshmallow fl owers in the second year of vegetation.

DISCUSSION
In the available scientifi c literature there is lack of information concerning the quantity of marshmallow fl ower yield.Flowers are only mentioned as an additional product obtained in the production of roots.Although fl owers and roots show similar medicinal properties, the former are of secondary importance and currently there is small demand for them as raw material.In this experiment, the yield of air dry fl owers of one-year-old plants was much smaller than two-year-old (on average 17.2 dt ha -1 and 27.8 dt ha -1 , respectively).As concerns methods of plantation establishment, signifi cant differences (in terms of seedling propagation) only in the fi rst year of vegetation were recorded.
In Poland, a growing interest in the production of herbal plant seedlings in multi-cell propagation trays has been observed (A n d r u s z c z a k and W i ś n i e ws k i , 2007; S u g i e r , 2004; K o ł o d z i e j and N a jd a , 2007).According to B e r b e ć (2002) as well as Z a o r s k i and K o ł o d z i e j (2000), this system of seedling production could be an important factor of yields and raw material quality increase.Such seedlings have a well-developed root system that ensures a 100% rooting rate after planting in the fi eld as well as a shorter  period of adaptation to the new environment.Research conducted so far has indicated that marshmallow cultivated from seedlings produced in multiplates was characterized by faster growth and development rates and generated higher root weight than plants cultivated from seedlings obtained in a plastic house (A n d r u s z c z a k and W i ś n i e w s k i , 2007).This experiment proves that using multi-cell trays for seedling production exerted a positive effect also on the yield and the number of fl owers in the fi rst year of plant vegetation.
Using the polypropylene sheet (after seed sowing) was found to have a positive infl uence on the fl owering and fl ower yield.According to literature, favourable conditions for the growth and development of plants are ensured by the peculiar microclimate under the polypropylene sheet, particularly higher air and soil temperature and higher humidity as compared to the fi eld with no cover (C ě r n e , 1994; S i w e k , 1999).Covering the plots with polypropylene sheet in the fi rst year of plant vegetation resulted in earlier fl owering (3 to 8 days than in the control object), and a signifi cantly greater number and weight of fl owers.In the second year of vegetation, however, the infl uence of this cultivation method on the traits examined was not observed.

CONCLUSIONS
1. Two-year-old marshmallow plants reached the full fl owering stage sooner and showed a higher yield potential, as compared to plants in the fi rst year of vegetation.2. The compared methods of plantation establishment signifi cantly modifi ed yields and number of fl owers only in the case of one-year-old plants.3.In the fi rst year of vegetation, the best results were achieved when plants were grown from seedlings produced in multi-cell propagation trays.Plants cultivated in this manner produced the highest yield of fresh and air dry matter of fl owers and were characterized by the greatest number of fl owers.4. Using the cover of polypropylene sheet after the seeds were sown accelerated the full fl owering stage and signifi cantly increased the yield of fl owers, as compared to those not covered.
. The above trend in the years 2002 and 2003 was observed until the end of July and the middle of August, respectively, whereas in the last year of research, throughout the entire fl owering stage.When analysing the fl ower yield during the successive collections, it was found that the most intensive fl owering of marshmalow cultivated from direct sowing occured in early August in 2002 and in the second half of this month in the other years.The plants cultivated from seedlings produced the highest yield of fl owers in the second half of July and early August in the years 2002 and 2003, and in the second half of August in the last year of research.

Table 1
Mean decade air temperature and total rainfall in2002-2004.
(data from Zamość Meteorological Station)

Table 2
Numer of days to the date of reaching full blooming stage.

Table 3
Total yield of fresh and air dry mass of fl owers and number of fl owers per plant.