Acclimation of photosynthesis to high irradiance in rice: gene expression and interactions with leaf development.
نویسندگان
چکیده
Rice (Oryza sativa L.) has been used to study the long-term responses of photosynthesis to high irradiance focusing on the composition of the photosynthetic apparatus and leaf morphology. Typical sun/shade differences in chloroplast composition are seen in the fifth leaf following growth in high irradiance compared with low irradiance (1000 and 200 micromol m(-2) s(-1), respectively): higher light-saturated rates of photosynthesis (P(max)), higher amounts of Rubisco protein, and a lower chlorophyll a:b ratio. In addition, leaves were thicker under high light compared with low light. However, responses appear more complex when leaf developmental stage is considered. Using a system of transferring plants from low to high light in the laboratory responses that occur before and after full leaf extension have been studied. Acclimation of photosynthesis is limited by leaf age: the transfer to high light, post-leaf extension, is characterized by alterations in chlorophyll a:b but not in Rubisco protein, which may be limited by leaf morphology. Microarray analysis of gene expression was carried out on plants that were transferred to high light post-leaf extension. A down-regulation of light-harvesting genes was seen. No change in the expression level of Rubisco genes was observed. Up-regulation of genes involved in photoprotection was observed. It was also shown that high-light leaf morphology is established prior to formation of the zone of cellular elongation and division. The endogenous and environmental factors which establish the characteristics of high light acclimation may be important for attaining high rates of assimilation in leaves and crop canopies, and the fifth leaf in rice provides a convenient model system for the determination of the mechanisms involved.
منابع مشابه
Study of Biochemical and Molecular Changes of Iranian Rice Cultivars in Interaction with Bacterial Pathogen Xanthomonas oryzae pv. oryzae Causes Leaf Blight Disease
Rice bacterial blight caused by Xanthamonos oryzae pv. oryzae is one of the most destructive bacterial diseases of rice in some areas of rice cultivation in the world, especially in the tropics of Asia. The low efficiency of disease management methods, especially chemical methods, has led to more research on recognizing resistant cultivars and understanding resistance mechanisms through the stu...
متن کاملDifferential adaptation of two varieties of common bean to abiotic stress: II. Acclimation of photosynthesis.
The photosynthetic characteristics of two contrasting varieties of common bean (Phaseolus vulgaris) have been determined. These varieties, Arroz and Orfeo, differ in their productivity under stress conditions, resistance to drought stress, and have distinctly different stomatal behaviour. When grown under conditions of high irradiance and high temperature, both varieties displayed evidence of p...
متن کاملNitrogen can improve the rapid response of photosynthesis to changing irradiance in rice (Oryza sativa L.) plants
To identify the effect of nitrogen (N) nutrition on the dynamic photosynthesis of rice plants, a pot experiment was conducted under two N conditions. The leaf N and chlorophyll levels, as well as steady-state photosynthesis, were significantly increased under high N. After the transition from saturating to low light levels, decreases in the induction state (IS%) of leaf photosynthesis (A) and s...
متن کاملAcclimation of photosynthesis to light and canopy nitrogen distribution: an interpretation.
BACKGROUND AND AIMS Acclimation of photosynthesis to light and its connection with canopy nitrogen (N) distribution are considered. An interpretation of a proportionality between light-saturated photosynthesis and local averaged leaf irradiance is proposed by means of a simple model. MODEL The model assumes (a) local irradiance drives synthesis of photosynthetic protein from metabolic N; (b) ...
متن کاملA cost–benefit analysis of acclimation to low irradiance in tropical rainforest tree seedlings: leaf life span and payback time for leaf deployment
The maintenance in the long run of a positive carbon balance under very low irradiance is a prerequisite for survival of tree seedlings below the canopy or in small gaps in a tropical rainforest. To provide a quantitative basis for this assumption, experiments were carried out to determine whether construction cost (CC) and payback time for leaves and support structures, as well as leaf life sp...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of experimental botany
دوره 56 411 شماره
صفحات -
تاریخ انتشار 2005