干旱区生态环境知识资源中心

In the years 1992 to 1994 the quality of amaranth Amaranthus mantegazzianus L., the Elbrus variety, cultivated after winter intercrop triticale Dagro was investigated. Trials were performed in irrigation-free conditions of south Slovakia, experimental station of Slovak University of Agriculture Nitra-Dolna Malanta. The site belongs to warm and moderate arid climatic region with average annual sum of precipitation 561 mm, for the growing season 327 mm. Average gaily air temperature is 9.7 degrees C, for the growing season 16.2 degrees C. Soil of experimental site is learn, in the subsoil horizon clay loam luvisol with medium content of humus and high content of nutrients. Amaranth was seeded after harvest of winter intercrop in the second half of May, only in 1992 at the beginning of June in two row spacings (0.375 and 0.500 m). After full emergence plants were singled to 400 thousand of plants per 1 ha and the stand was heed twice during the growing season. Amaranth produced 3.79 to 8.54 t.ha(-1) of dry matter, higher yields were obtained under row spacing of 375 mm (Tab. Ill). Very low yields in 1993 were connected with delayed emergence (for strong overdrying of soil profile during growth of triticale amaranth started to emerge at the beginning of July), growth and development in conditions of shortening day and with approximately lower average daily temperatures by 4 degrees C during growing season of amaranth compared with the years 1992 and 1994 (Tab. II). The content of main nutrients in different organs of amaranth (Tab. V), the content of nutrients including microelements in the time of harvest at the onset of anthesis (Tab. TV), changes ill qualitative indicators during ontogenesis of amaranth (Tab. VI), withdrawal of nutrients by harvest (Tab. VII) and the effect of row spacing on the content of main nutrients were investigated (Fig. I). On average of experimental years amaranth in I kg of dry matter contained 129.93 g crude protein. 221.30 g fibre, 38.40 g fats, 3.66 g NO3-N, 3.48 g P, 20.03 g Ca, 9.21 g Mg, 35.53 g K and 0.37 g Na. High content of K was compensated by high content of bivalent cations of Ca and Rig, and therefore the values of tetanic ratio were low (Tab. IV). During ontogenesis of amaranth the content of crude pl olein, amino acids and mineral elements was failing, while the fibre content was increasing. The effect of row spacing on the content of main nutrients was not unambiguous (Fig. I). Above-ground biomass of amaranth on average for experimental years withdrew from 1 ha: 140.7 kg N, 23.57 kg P, 135.62 kg Ca, 62.32 kg Mg, 240.50 kg K and 2.49 kg Na. Of the microelements this ranged from 0.2 g (Cd) to 961.5 g (Fe) per 1 ha. It can be said that the quality of above-ground biomass of amaranth is in many indicators comparable with the quality of our most important fodder crop - lucerne.