Leaves of rye seedlings (Secale cereale L.) grown in the presence of four chlorosis-inducing herbicides under a low light intensity of 10 lux formed chlorophyll. When segments of such dim-light-grown leaves were exposed to 30,000 lux at either 0 degrees C or 30 degrees C, treatments with aminotriazole or haloxidine (group 1) showed no or only minor changes of their chlorophyll contents. In trea...

In a previous paper (l), studies were made of chlorophyll degradation products frequently to be found in leaf extracts. The solation of spectroscopically pure chlorophylls a and b was then considered (2). The logical outcome of these studies is the application of the data to the determination of chlorophyll in extracts. It is complicated by the suggestion that chlorophyll as known to Willstatte...

In a previous paper (l), studies were made of chlorophyll degradation products frequently to be found in leaf extracts. The solation of spectroscopically pure chlorophylls a and b was then considered (2). The logical outcome of these studies is the application of the data to the determination of chlorophyll in extracts. It is complicated by the suggestion that chlorophyll as known to Willstatte...

During natural or dark-induced senescence, chlorophyll degradation causes leaf yellowing. Recent evidence indicates that chlorophyll catabolic enzymes (CCEs) interact with the photosynthetic apparatus; for example, five CCEs (NYC1, NOL, PPH, PAO and RCCR) interact with LHCII. STAY-GREEN (SGR) and CCEs interact with one another in senescing chloroplasts; this interaction may allow metabolic chan...

Senescence is a highly organized and well-regulated process. As much as 75% of total cellular nitrogen may be located in mesophyll chloroplasts of C(3)-plants. Proteolysis of chloroplast proteins begins in an early phase of senescence and the liberated amino acids can be exported to growing parts of the plant (e.g. maturing fruits). Rubisco and other stromal enzymes can be degraded in isolated ...

Parasitic organisms exemplify morphological and genomic reduction. Some heterotrophic, parasitic plants harbor drastically reduced and degraded plastid genomes resulting from relaxed selective pressure on photosynthetic function. However, few studies have addressed the initial stages of plastome degradation in groups containing both photosynthetic and nonphotosynthetic species. Corallorhiza is ...

Loss of green color in leaves results from chlorophyll (Chl) degradation in chloroplasts, but little is known about how Chl catabolism is regulated throughout leaf development. Using the staygreen (sgr) mutant in rice (Oryza sativa), which maintains greenness during leaf senescence, we identified Sgr, a senescence-associated gene encoding a novel chloroplast protein. Transgenic rice overexpress...

In a previous paper (l), studies were made of chlorophyll degradation products frequently to be found in leaf extracts. The solation of spectroscopically pure chlorophylls a and b was then considered (2). The logical outcome of these studies is the application of the data to the determination of chlorophyll in extracts. It is complicated by the suggestion that chlorophyll as known to Willstatte...