The objective of these studies was to investigate possible effects of the environmental factors in achieving high yields and good quality leaves in the grown broad-leaf great plantain.

Field trials were conducted over 1998 and 1999 on the localities, as follows: Pančevo, marsh meadow soil at the altitude of 70 m in the environmental conditions existing in South Banat, i.e. West Serbia, followed by Gorobilje, brown soil at the altitude of 420 m.

Preliminary results of the simultaneously conducted investigation indicated that the highest yield of dry leaf averaging 2560.5 kg/ha was achieved on the locality of Pančevo, with 2145.5 kg/ha great plantain dry leaf recorded on that of Gorobilje.

On a two-year basis, higher yields were achieved in 1999 on both localities.

In both research years, aucubin was found to be higher (1.3%) in the leaf of great plantain produced on the locality of Gorobilje.

Key words: great plantain, dry leaf, yields, environmental conditions, aucubin.

The tendency of medicinal plants natural resources depletion has been rather expressed in Yugoslavia in recent time. On the other hand, the demands for medicinal plants are on steady rise day in day after, which imposes a great need for plantation type of their growth (Stepanović, 1998).

Plantation growth of medicinal plants is being practiced in the areas of differing environmental factors that have a decisive role in achieving high yields and good quality medicinal plants. Great plantain is widely spread almost everywhere in the world and may do well from moderate-warm to cold areas. The family Plantaginaceae consists of three strains with around 250 species, with Plantago strain, consisting of 15 species, as the only one being successful in Yugoslavia.

The subject of our study has been Plantago major L. i.e. broad-leaf great plantain. This species is widely spread in the nature, but aiming at better production quality, its plantation growth has come into use. Young leaves of great plantain have been long used as an outstandingly healthy vegetable in culinary art, particularly in recent years with healthy food expansion in human diet. Great plantain leaves are highly rich in vitamins and mineral matter and phytoncide and its seeds are considered to be exceptionally nutritional. Medicinal value of great plantain is of paramount importance, particularly that of its young fresh leaves which have high antibacterial effects and thus are broadly used in medicine (Jovanović, 1987). Taking great significance of broad-leaf great plantain and its growing demands into account, its high yields and leaf mass good quality are assumed to highly depend upon the environmental factors dominating over its production. Therefore, these were reasons requiring from us to study the possibilities and presumable effects of broad-leaf great plantain cultivation on yield and leaf mass quality in different environmental conditions.

The experiments were carried out over two vegetation seasons of 1998 and in 1999. Field trials were carried out on the experimental plots on two different localities, South Banat (Pančevo) and West Serbia (Gorobilje). After properly prepared soil, planting was performed. Broad-leaf great plantain planting material was produced at the Institute of Medicinal Plants "Dr Josif Pančić" in Pančevo. Planting was done manually by means of dibbles, with vegetation space sized 50x30 cm. Common cultural practices for this crop were applied during growing season.

On the locality of Pančevo, the experiments were set up on the marsh brown soil at the altitude of 70m. Planting of great plantain was done in mid-March in both years. Precipitation amounts over the growing seasons of 1998 and 1999 amounted to 288 mm and 617 mm, respectively, being more abundant in 1999.

On the locality of Gorobilje, the experiments were conducted on the brown type of soil, with plots at the altitude of 420 m. In both years, planting proceeded in the last decade of March. During growing seasons of great plantain, the mean daily air temperatures amounted to 18^oC for both years. Also, lower precipitation amounts (438 mm) were determined during the growing season of 1998 compared to those recorded in 1999 (570 mm).

Biomass - leaf picking was performed at the beginning of July in 1998 (7^th and 8^th July) on both localities. In 1999, picking was also done at the beginning of July (4^th July - Pančevo and 10^th July - Gorobilje).

The harvested leaf mass was dried up in the natural way on a well shaded draft spot. Aucubin was laboratory detected, applying standard methods.

Yield of dry leaves

The results of great plantain dry leaf yield have shown the differences in terms of this trait, both per localities and per years (Tab.1).

The highest great plantain dry leaf yield of 2664 kg/ha was achieved on the locality of Pančevo during growing season of 1999, and the lowest one of 2123 kg/ha on that of Gorobilje in 1998. This can be attributed to more suitable environmental conditions on the locality of Pančevo. In both years, on this locality were achieved higher great plantain dry leaf yields (on average 2560.5 kg/ha) compared to those attained on that of Gorobilje with an average dry leaf yield recorded to be 2154.5 kg/ha.

So obtained data on dry leaf yields on the localities with different altitudes are in agreement with results of Pavlović et al., 1998, who pointed out a high impact of the environmental factors on dry leaves of parsley.

Also, the yield of dill dry leaf was found to highly depend upon the environmental factors dominating over the growing season (Jevđović et al. 1998). On both localities, higher great plantain dry leaf yields were achieved during growing season of 1999 (on average 2425 kg/ha) compared to those achieved in 1998 (on average 2290 kg/ha great plantain dry leaves).

So obtained results on dry leaf yield can be attributed to higher precipitation amounts in 1999 on both localities compared to those evidenced during the growing season of 1998.

Aucubin content

Content of aucubin studied on a two-year basis and per localities expressed in percentages is given in Table 2.

Aucubin content in great plantain dry leaf was not consistent to the yield achieved on the localities under way. The highest aucubin content was established in the leaves of great plantain produced on the locality of Gorobilje, amounting to 1.3% in both years. The lowest aucubin content of 0.9% was established in dry leaves of great plantain produced on the locality of Pančevo in 1999.

Higher content of aucubin (1.3%) was determined in the leaves of great plantain produced under the environmental conditions of Gorobilje in both years. On a two-year basis, no significant differences in aucubin content existed in great plantain leaves (1.1 and 1.2%).

Based upon 2-year study, conducted over the two growing seasons on the two various localities, on the environmental effects on dry leaf yield and quality, the following may be concluded:

The yield of dry great plantain leaves and aucubin content were influenced by the environmental factors.

The highest great plantain dry leaf yield of 2664 kg/ha was achieved over the growing season of 1999 on the locality of Pančevo.

Higher dry leaf yields were attained on both localities over the growing season of 1999, as a consequence of more suitable environmental factors in that year.

The highest aucubin content of 1.3% was determined in the dry leaves of great plantain produced on the locality of Gorobilje in both years, and

On a two-year basis, aucubin content indicated fairly uniform values without variations expressed.

1. Jevđović R., Radanović D. and Živković D. (1998): Chamomille, mustard and dill yield depending on agroecological conditions and agricultural practices, Proceedings of 2^nd Balkan Symposium on Field Crops, vol. 2, 417-420.

2. Jovanović Đ. (1987): Povrće - hrana i lek, In: Voće i povrće - hrana i lijek, NIO Pobeda Titograd, 134-137.

3. Pavlović R., Jevđović R., Bjelić V. and Maletić R. (1998): Mogućnosti proizvodnje peršuna lišćara u brdsko-planinskom području Srbije, Savremena poljoprivreda, vol. 46, vanredni broj, 329-333.

4. Stepanović B. (1998): Proizvodnja lekovitog i aromatičnog bilja, IMPR "Dr Josif Pančić", Belgrade.