“…The correlations among harvest index, grain yield and biological yield, therefore, have been investigated by many authors using very different agricultural crops. Only some selected publications on these topics shall be mentioned here: THURLING (1974), CAMPBELL and KONDRA (1978), DEGENHART andKoNDRA (1981, 1984), SERNYK and STEFANSSON (1983), JENKINS and LEITCH (1986), GROSSE (1989) with rapeseed; SINGH and STOSKOPF (1971), RosiELLE andFREY (1975 a, 1975 b), TAKIDA and FREY (1976), TAKEDA and FREY (1977), TAKEDA et al (1979), TAKEDA et al (1980), JOHNSON et al (1983) with oat; SINGH and STOSKOPE (1971), SYME (1972), NASS (1973), FISCHER and KERTESZ (1976), DONALD and HAMBLIN (1976), BHATT (1977), AUSTIN et al (1980), BLASL (1982), FEIL (1987), MALIK et al (1988) with wheat; SINGH and STOSKOPF (1971), DONALD and HAMBLIN (1976), RIGGS et al (1981aRIGGS et al ( , 1981b, BLASL (1982) with barley; BLASL (1982), RUSSELL (1985) with maize.…”