Mechanisms controlling metabolite concentrations of the Calvin Benson Cycle.

Maintaining proper metabolite levels in a complex metabolic network is crucial for maintaining a high flux through the network. In this paper, we discuss major regulatory mechanisms over the Calvin Benson Cycle (CBC) with regard to their roles in conferring homeostasis of metabolite levels in CBC. These include: 1) Redox regulation of enzymes in the CBC on one hand ensures that metabolite levels stay above certain lower bounds under low light while on the other hand increases the flux through the CBC under high light.

Study on Microstructure of Fiber Laser Welding of CoCrCuFeNi High Entropy Alloy.

A CoCrCuFeNi high-entropy alloy was successfully welded in this study using fiber laser welding. The effects of the welding parameters on the microstructure and mechanical properties were studied. Three zones were formed: the fusion zone, partial melting zone, and base metal.

3dCAP-Wheat: An Open-Source Comprehensive Computational Framework Precisely Quantifies Wheat Foliar, Nonfoliar, and Canopy Photosynthesis.

Canopy photosynthesis is the sum of photosynthesis of all above-ground photosynthetic tissues. Quantitative roles of nonfoliar tissues in canopy photosynthesis remain elusive due to methodology limitations. Here, we develop the first canopy photosynthesis model incorporating all above-ground photosynthetic tissues and validate this model on wheat with state-of-the-art gas exchange measurement facilities.

Diurnal and Seasonal Variations of Photosynthetic Energy Conversion Efficiency of Field Grown Wheat.

Improving canopy photosynthetic light use efficiency and energy conversion efficiency (ε ) is a major option to increase crop yield potential. However, so far, the diurnal and seasonal variations of canopy light use efficiency (LUE) and ε are largely unknown due to the lack of an efficient method to estimate ε in a high temporal resolution. Here we quantified the dynamic changes of crop canopy LUE and ε during a day and a growing season with the canopy gas exchange method.

Two major metabolic factors for an efficient NADP-malic enzyme type C4 photosynthesis.

Compared to the large number of studies focused on the factors controlling C3 photosynthesis efficiency, there are relatively fewer studies of the factors controlling photosynthetic efficiency in C4 leaves. Here, we used a dynamic systems model of C4 photosynthesis based on maize (Zea mays) to identify features associated with high photosynthetic efficiency in NADP-malic enzyme (NADP-ME) type C4 photosynthesis. We found that two additional factors related to coordination between C4 shuttle metabolism and C3 metabolism are required for efficient C4 photosynthesis: (1) accumulating a high concentration of phosphoenolpyruvate through maintaining a large PGA concentration in the mesophyll cell chloroplast and (2) maintaining a suitable oxidized status in bundle sheath cell chloroplasts.

Potential metabolic mechanisms for inhibited chloroplast nitrogen assimilation under high CO2.

Improving photosynthesis is considered a major and feasible option to dramatically increase crop yield potential. Increased atmospheric CO2 concentration often stimulates both photosynthesis and crop yield, but decreases protein content in the main C3 cereal crops. This decreased protein content in crops constrains the benefits of elevated CO2 on crop yield and affects their nutritional value for humans.

Increasing the comprehensive economic benefits of farmland with Even-lighting Agrivoltaic Systems.

Agrivoltaic combines crop planting and electricity generation on the same land, it is considered as an opportunity to resolve the competition for land use between food and energy production. In addition to growing crops, farmers can gain electricity with the installation of agrivoltaic systems on their farmland. They can use this clean energy for agricultural production or sell it for extra income.

Morphological and physiological factors contributing to early vigor in the elite rice cultivar 9,311.

Huanghuazhan (HHZ) and 9,311 are two elite rice cultivars in China. They have achieved high yield through quite different mechanisms. One of the major features that gives high yield capacity to 9,311 is its strong early vigor, i.

An in situ approach to characterizing photosynthetic gas exchange of rice panicle.

Background: Photosynthesis of reproductive organs in C cereals is generally regarded as important to crop yield. Whereas, photosynthetic characteristics of reproductive organs are much less understood as compared to leaf photosynthesis, mainly due to methodological limitations. To date, many indirect methods have been developed to study photosynthesis of reproductive organs and its contribution to grain yield, such as organ shading, application of herbicides and photosynthetic measurement of excised organs or tissues, which might be intrusive and cause biases.

A three-dimensional canopy photosynthesis model in rice with a complete description of the canopy architecture, leaf physiology, and mechanical properties.

In current rice breeding programs, morphological parameters such as plant height, leaf length and width, leaf angle, panicle architecture, and tiller number during the grain filling stage are used as major selection targets. However, so far, there is no robust approach to quantitatively define the optimal combinations of parameters that can lead to increased canopy radiation use efficiency (RUE). Here we report the development of a three-dimensional canopy photosynthesis model (3dCAP), which effectively combines three-dimensional canopy architecture, canopy vertical nitrogen distribution, a ray-tracing algorithm, and a leaf photosynthesis model.

Kinetic Modeling of Photorespiration.

Dynamic systems modeling is a method to study systematic properties of a complex system. The basic principles, procedures, and tools available to develop a dynamic systems model of complex metabolic processes are detailed. Here, a photosynthetic carbon metabolism model, which includes the Calvin Benson cycle, photorespiration, and starch and sucrose synthesis pathways, is used as an example to illustrate the whole process of model development.

Rapid stomatal response to fluctuating light: an under-explored mechanism to improve drought tolerance in rice.

Light inside a canopy constantly fluctuates. Under fluctuating light (FL) conditions, stomatal conductance and photosynthetic rate constantly change. In this study, we explored whether this dynamics of stomata movements upon FL influenced the water use efficiency of rice in the field.