Introduction and Economical Value of Some Species of the Malvaceae Family in the Republic of Moldova

Abstract

Abstract The family Malvaceae includes about 243 genera and at least 4 225 species of herbs, shrubs and trees. They are widely varied and include several important crops, which are mainly used as sources of fibre, food and beverages, medicines, timber. The species of the family Malvaceae: annual, Malva crispa and Malva meluca, native to East Asia, and perennial, Sida hermaphrodita, from North America, grown in monoculture in the experimental land of the Botanical Garden (Institute), served as subjects of the research, and the traditional crop Medicago sativa was used as control. The importance of the studied species of the family Malvaceae consists in their very rapid emergence and fast growth. The analysis of the chemical composition suggested that the dry matter of the studied species, at the 1st mowing contained 15.67-21.67 % raw protein, 2.15-4.46 % raw fats, 8.35-11.53 % minerals and 34.74-40.66 % nitrogen free extract, Medicago sativa - 17.03 %, 2.30 %, 33.31 %, 8.01 % and 39.41 % respectively, making them good candidates for use as livestock feed and for biomethane production. The nutritive value of 100 kg fresh mass of the studied Malvaceae species was 14.9-16.6 nutritive units and 153-173 MJ metabolizable energy, a nutritive unit contained 154.2-191.0 g digestible protein with high concentrations of limiting amino acids, the control - 21 nutritive units, 228 MJ and 164.3 g digestible protein, respectively. The calculated capacity of biomethane production of the studied Malvaceae species can reach 231-267 l/kg organic matter, Medicago sativa - 248 l/kg organic matter. The theoretical ethanol yield from structural carbohydrates of the dry biomass of stalks averaged 437-527 L/t in Malvaceae species, as compared to 485 L/t in corn. The best results were achieved by Sida hermaphrodita, due to its high amount of structural carbohydrates. These species may serve as feed for livestock, but also as multi-purpose feedstock for biorefinery in Moldova.