TITLE:
Photoperiod Affects in Vitro Flowering in Wild Peanut Arachis paraguariensis
AUTHORS:
Olubunmi Aina, Kenneth Quesenberry, Maria Gallo
KEYWORDS:
Flower; Tissue Culture; Day-Length; Photoperiod; Peanut; Arachis;In Vitro
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.3 No.5,
May
30,
2012
ABSTRACT: Arachis paraguariensis, a wild peanut species, is a potential experimental system for studying the molecular mechanisms of flowering in the genus Arachis. The present study was carried out to investigate the effect of photoperiod on in vitro reproductive behavior of five genotypes of A. paraguariensis. Day-lengths of 12, 16 and 24 h were tested to monitor in vitro flowering using growth chambers kept at 26?C ± 1?C and 60% ± 5% relative humidity under an illumination of 40 μmol?m–2?s–1. Flowering percentage of plantlets ranged from 35% to 93%, 20% to 75%, and 5% to 53% for 12, 16 and 24 h day-lengths, respectively. Genotype PI 262842 displayed the highest frequency of flowering under all the day-length treatments but in vitro flower bud initiation was delayed. The highest mean flowering percentage of 65% across all the genotypes for plantlets exposed to 12 h photoperiod is indicative that flowering induction actually occurred. The results presented in this paper provide evidence for photoperiodic flowering response as well as the occurrence of short day-length-enhanced flowering in A. paraguariensis.