We report on carrier-induced effects on emission and absorption in forward biased GaAs/AlGaAs V-groove quantum wire (QWR) diodes observed using low-temperature (10 K) photoluminescence (PL), electroluminescence (EL) and PL excitation (PLE) spectroscopy. In the case of simultaneous electron-hole injection we observe a band-gap renormalization (BGR) of at least 5 meV for a carrier density of approximate to 10(6) cm(-1), by comparing high-density EL spectra with low-density PLE spectra. In the case of electron injection of approximate to 10(6) cm(-1) we observe a complete quenching of the PLE absorption edge related to a Burstein-Moss shift of approximate to 35 meV. Hole band-filling is much less effective due to smaller subband spacing and larger density-of-states in the valence band.