TY JOUR TI BARLEY PHOTOSYNTHESIS AND YIELD INDICATORS USING COMPLEX FERTILIZERS AND GROWTH STIMULANTS KW spring barley KW yield KW photosynthetic potential KW growth stimulators JO Bulletin Samara State Agricultural Academy AU Vasin, V.G. AU Burunov, A.N. AU Mikhalkin, N.G. PY 2021 IS 6 PB Samara State Agricultural Academy