Enhanced Chlorophyll Degradation Triggers the Pod Degreening of “Golden Hook,” a Special Ecotype in Common Bean (Phaseolus vulgaris L.)

Abstract

To reveal genetic factors or pathways involved in the pod degreening, we performed transcriptome and metabolome analyses using a yellow pod cultivar of the common bean “golden hook” ecotype and its green pod mutants yielded via gamma radiation. Transcriptional profiling showed that expression levels of red chlorophyll catabolite reductase ( RCCR , Phvul.008G280300 ) involved in chlorophyll degradation was strongly enhanced at an early stage (2 cm long) in wild type but not in green pod mutants. The expression levels of genes involved in cellulose synthesis was inhibited by the pod degreening. Metabolomic profiling showed that the content of most flavonoid, flavones, and isoflavonoid was decreased during pod development, but the content of afzelechin, taxifolin, dihydrokaempferol, and cyanidin 3- O -rutinoside was remarkably increased in both wild type and green pod mutant. This study revealed that the pod degreening of the golden hook resulting from chlorophyll degradation could trigger changes in cellulose and flavonoids biosynthesis pathway, offering this cultivar a special color appearance and good flavor.

Integrative analyses of morphology, physiology, and transcriptional expression profiling reveal miRNAs involved in culm color in bamboo

“…Similar results were observed in the present study ( Figures 2B , C ). Many studies have shown that flavonoids, carotenoids, and anthocyanins may be involved in plant coloration (Hu et al, 2020 ; Jiang et al, 2020 ; Wei et al, 2021 ). In P. violascens cv.…”

Cell wall break down of pitanga fruit (Eugenia uniflora L.) is associated with pectic solubilisation and softening

“…(2007). As known, the expression of carotenoids in fruits can occur in two ways: through the synthesis of the pigments, concomitant with chlorophyll degradation, or through unmasking, a result of chlorophyll degradation (Chitarra & Chitarra, 2005; Hu et al ., 2020). The loss of greenish coloration, present in fruits at stage 1, suggests chlorophyll degradation.…”

Nitric oxide delays the postharvest nutritional quality decline of “Golden Hook” beans

“…"Golden Hook" beans are a low-fat and low-sodium healthy vegetable with full seeds, bright pod color, and little fiber content and are rich in carbohydrates, mineral elements, protein plant sterols, flavonoids, and other phytochemicals beneficial to health (Tor-Roca et al, 2020). In preliminary research, we found that the variety is prone to color change, turning purple, fading, and decay with a storage period of 3-4 days at 20 • C. The color change is a direct reflection of the senescence stage (Khaliq et al, 2021;Hu et al, 2020).…”

“…In preliminary research, we found that the variety is prone to color change, turning purple, fading, and decay with a storage period of 3–4 days at 20°C. The color change is a direct reflection of the senescence stage (Khaliq et al., 2021; Hu et al., 2020).…”