Features of productivity formation of different maturity terms perennial cereal grasses between mowings depending on the fertilizing system

Abstract

Purpose. To establish productivity indicators and terms of mowing perennial grasses of different maturity terms depending on fertilizer, Methods. Field, laboratory, mathematical and statistical. Results. The research results of productivity indicators of different maturity terms perennial grasses depending on the fertilization system between the mowings and the peculiarities of the growth of dry biomass during formation of the first mowing on the sod-podzolic soil of the Carpathian region, conducted during 2011-2013, are presented. Conclusions. Productivity of various types of perennial grasses on nitrogen-free backgrounds in the 1st mowing varied between 1.22-1.67 t/ha of dry mass, in the 2nd – 1.06-1.40, and in the 3rd – in in the range of 0.79-1.01 t/ha of dry mass. The most productive in the 1st mowing were Bromus inermis and Phleum pretense L., in the 2nd – Dactylis glomerata, Festuca orientals (Hack.), and Lolium perenne. The most uniform distribution of the dry mass yield in the mowings with the smallest coefficient of variation (6-12%) was characteristic of the Dactylis glomerata, and the least uniform with the largest coefficient (29-35%) – of the Phleum pretense L. Nitrogen had the greatest effect on the productivity of cereal grass stands. With the application of P60K60, productivity increased by 3-23% compared to the variant without fertilizers, and with the application of N90P60K60 – by 1.8-1.9 times. The highest indicators of daily increase in dry mass (75-206 kg/ha), leaf surface area (30.3-43.1 thousand m2/ha) and net productivity of photosynthesis (1.16-4.78 g/m2 per day) in the 1st mowing fell on the period of tuberization-the beginning of the earing of cereal grasses. The growth of productivity of dry biomass, leaf surface area and net productivity of photosynthesis occurs before the flowering phase of grasses.