Anthocyanins are protective pigments that accumulate in plant organs such as fruits and leaves, and are nutritionally valuable components of the human diet. The MYB10 transcription factor (TF) plays an important role in regulating anthocyanin biosynthesis in Malus crabapple leaves. However, little is known about how the promoter regulates McMYB10 expression and influences the substantial variation in leaf anthocyanin accumulation and coloration that is observed in different crabapple cultivars. In this study, we analyzed leaf coloration, anthocyanin levels, and the expression levels of McMYB10 in the leaves of 15 crabapple cultivars with three leaf colors at various development stages, and showed that the expression of McMYB10 correlates positively with anthocyanin accumulation. We also examined the relationship between the number of R6 and R1 elements in the McMYB10 promoters of the different cultivars and the pigmentation of the new buds of spring-red cultivars, as well as the methylation level of the McMYB10 promoters at different development stages in three representative crabapple cultivars. The ratio of R6/R1 minisatellites in the promoters correlated with the color and anthocyanin accumulation in new crabapple buds, and we concluded that the differences in promoter structure and methylation level of the McMYB10 promoters coordinately affect the leaf color of crabapple cultivars.
Ji Tian, Ke-ting Li, Shi-ya Zhang, Jie Zhang, Ting-ting Song, Yong-jun Zhu, and Yun-cong Yao
Jiayi Ji, Zhenglin Li, Ji Tian, Jie Zhang, Yanfen Lu, Xiaoxiao Qin, Jianjun Li, Liqiang Liu, Zhe Gao, Yujing Hu, and Yuncong Yao
Danielle D. Treadwell, George J. Hochmuth, Robert C. Hochmuth, Eric H. Simonne, Lei L. Davis, Wanda L. Laughlin, Yuncong Li, Teresa Olczyk, Richard K. Sprenkel, and Lance S. Osborne
Consumer demand for fresh market organic produce combined with the increasing market share of ready-to-eat products indicates the potential for expansion of an organic culinary herb market. Barriers to organic herb greenhouse production are high as a result of lack of available technical information and the low number of producers experienced in this area. There is a critical need for information and technologies to improve the management of organic soil and fertilizer amendments to optimize crop yields and quality, manage production costs, and minimize the risk from groundwater nitrogen (N) contamination. Because of limited information specific to organic culinary herb production, literature on organic vegetable transplants and conventional basil (Ocimum basilicum) production was also considered in this review. Managing N for organic crops is problematic as a result of the challenge of synchronizing mineralization from organic fertilizer sources with crop N demand. A combination of materials, including locally formulated composts, supplemented with standardized commercially formulated fertilizer products is one method to ensure crops have access to mineral N throughout their development. In experimental greenhouse systems, local raw materials are frequently used as media amendments to satisfy partial or complete crop fertility requirements. This makes comparisons among experiments difficult as a result of the wide variety of raw materials used and the frequent interactions of fertilizer source and planting media on nutrient availability. Nitrogen mineralization rates are also influenced by additional factors such as the environmental conditions in the greenhouse and physical and chemical properties of the media and fertilizer. Despite the variability within and among experimental trials, yields and quality of organically grown crops are frequently similar to, and occasionally better than, conventionally grown crops.