Effects of Seed Maturation Temperature on Seed Yield Characteristics and Subsequent Generations of Lupin

Phenology and morphology of white lupin (Lupinus albus L.) varied in plants derived from different seed lots of the same cultivar, presumably because thermosensitive genotypes are affected by thermal environment during early development. This study was conducted to determine whether the maternal thermal environment of developing seeds influenced subsequent plant development. We grew white lupin plants cv. Ultra, at the mainstem first flower stage, in controlled growth chambers at 13 or 28C temperature under a 14‐h photoperiod. At harvest maturity, yield components were quantified. The two resultant seed populations were planted in the greenhouse, and at the mainstem first flower stage, one‐half of each group of plants was placed in growth chambers at 13 or 28°C. This regimen was carried out through three generations. Seed dry weight per plant and weight per seed were greater for plants matured at 13°C than at 28°C. All plants produced from maternal seed that had matured at 28°C developed at a slower rate than those at 13°C. Floral events in these plants lagged behind by as much as 15 d. No differences were observed in mainstem vegetative node number. We concluded that phenotypic variability among seedlots of the same genotype can be caused by thermal environmental conditions occurring as embryos develop. These results show that thermal environment during seed production can affect subsequent crop performance, which can impact cultivar production and consistency among years.