White Traits Research Articles

Bcwf regulates the white petal color in pak choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis]

Flower color is important in determining the ornamental value of Brassica species. However, our knowledge about the regulation of flower color in pak choi [Brassica campestris (syn. Brassica rapa) ssp. chinensis] is limited. In this study, we investigated the molecular mechanism underlying white flower traits in pak choi by analyzing a genetic population with white and yellow flowers. Our genetic analysis revealed that the white trait is controlled by a single recessive gene called Bcwf. Through BSA-Seq and fine mapping, we identified a candidate gene, BraC02g039450.1, which is similar to Arabidopsis AtPES2 involved in carotenoid ester synthesis. Sequence analysis showed some mutations in the promoter region of Bcwf in white flowers. Tobacco transient assay confirmed that these mutations reduce the promoter's activity, leading to downregulation of Bcwf expression in white flowers. Furthermore, the silencing of Bcwf in pak choi resulted in lighter petal color and reduced carotenoid content. These findings provide new insights into the molecular regulation of white flower traits in pak choi and highlight the importance of Bcwf in petal coloring and carotenoid accumulation.

Evidence forPPC1,a Determinant of the Pilei-Pellis Color ofAgaricus bisporusFruitbodies

In the present study, we investigated the genetic basis of mushroom cap color. In first generation hybrids between a brown isolate and the white commercial hybrid U 1, the white trait was recessive. Color was determined using color meter technology in second generation hybrids obtained by crossing the homokaryotic progeny of a first generation hybrid with a homokaryon from U 1. Statistical analysis revealed a bimodal distribution describing two classes of white and not-white hybrids. We postulate that a recessive allele at a single locus (PPC1) encodes the white pilei-pellis color. Joint segregation analyses indicated thatPPC1was linked to theADH(alcohol dehydrogenase) locus. Through the analysis of the heterokaryotic progeny of the first generation hybrid, a recombination model is proposed in whichPPC1is located between the centromere and theADHlocus.

A White-Eye Mutant of Protophormia terraenovae (Diptera: Calliphoridae): Mode of Inheritance and Photoperiodic Response

A spontaneous mutant, white , with the phenotype of white compound eyes was isolated from a laboratory culture of Protophormia terraenovae (Robineau-Desvoidy) that originated from Obihiro, Japan. Standard genetic crosses showed that the white trait is controlled by an autosomal recessive. The photoperiodic response for the induction of adult diapause was examined at different temperatures and light intensities. The wild-type P. terraenovae showed a long-day photoperiodic response under all conditions examined. When the light intensity of the photophase was 500 or 20,000 lux at 25°C, white adults reproduced directly without diapause both under long-day and short-day conditions. Under 500 lux at 20°C or under 0.5 lux at 25°C, however, the white strain showed a long-day photoperiodic response.