Publications by authors named "Jimei Han"

The effect of crop domestication on photosynthetic productivity has been well-studied, but at present, none examines its impacts on leaf anatomy and, consequently, light use efficiency in cotton. We investigated leaf and vein anatomy traits, light use efficiency (LUE) and gas exchange in 26 wild and 30 domesticated genotypes of cotton grown under field conditions. The results showed that domestication resulted in a higher photosynthetic rate, higher stomatal conductance, and lower lamina mass per area.

View Article and Find Full Text PDF

Although our observing capabilities of solar-induced chlorophyll fluorescence (SIF) have been growing rapidly, the quality and consistency of SIF datasets are still in an active stage of research and development. As a result, there are considerable inconsistencies among diverse SIF datasets at all scales and the widespread applications of them have led to contradictory findings. The present review is the second of the two companion reviews, and data oriented.

View Article and Find Full Text PDF

Solar-induced chlorophyll fluorescence (SIF) is a remotely sensed optical signal emitted during the light reactions of photosynthesis. The past two decades have witnessed an explosion in availability of SIF data at increasingly higher spatial and temporal resolutions, sparking applications in diverse research sectors (e.g.

View Article and Find Full Text PDF

A photochemical model of photosynthetic electron transport (PET) is needed to integrate photophysics, photochemistry, and biochemistry to determine redox conditions of electron carriers and enzymes for plant stress assessment and mechanistically link sun-induced chlorophyll fluorescence to carbon assimilation for remotely sensing photosynthesis. Towards this goal, we derived photochemical equations governing the states and redox reactions of complexes and electron carriers along the PET chain. These equations allow the redox conditions of the mobile plastoquinone pool and the cytochrome b f complex (Cyt) to be inferred with typical fluorometry.

View Article and Find Full Text PDF

In higher plants, photosystems II and I are found in grana stacks and unstacked stroma lamellae, respectively. To connect them, electron carriers negotiate tortuous multi-media paths and are subject to macromolecular blocking. Why does evolution select an apparently unnecessary, inefficient bipartition? Here we systematically explain this perplexing phenomenon.

View Article and Find Full Text PDF

Solar-induced Chl fluorescence (SIF) offers the potential to curb large uncertainties in the estimation of photosynthesis across biomes and climates, and at different spatiotemporal scales. However, it remains unclear how SIF should be used to mechanistically estimate photosynthesis. In this study, we built a quantitative framework for the estimation of photosynthesis, based on a mechanistic light reaction model with the Chla fluorescence of Photosystem II (SIF ) as an input (MLR-SIF).

View Article and Find Full Text PDF

Solar-induced chlorophyll fluorescence (SIF) has been used to infer photosynthetic capacity parameters (e.g., the maximum carboxylation rate V , and the maximum electron transport rate J ).

View Article and Find Full Text PDF
Article Synopsis
  • The induction and relaxation processes of photochemistry and non-photochemical quenching (NPQ) in plants take time and are affected by changing environmental conditions, which leads to complex interactions during photosynthesis.
  • In experiments with poplar and cotton at different temperatures and light levels, it was found that photosystem II's reaction center (qL) increases gradually with light intensity, while NPQ responds quickly but stabilizes, showing distinct temperature effects on these processes.
  • The study highlights that during light fluctuations, the slow ramp-up of qL is a more significant limitation on photosynthesis than the slow down of NPQ, suggesting that understanding these dynamics can help enhance photosynthetic efficiency in variable environments.
View Article and Find Full Text PDF

Mesophyll conductance (gm) is a crucial leaf trait contributing to the photosynthetic rate (AN). Plant domestication typically leads to an enhancement of AN that is often associated with profound anatomical modifications, but it is unclear which of these structural alterations influence gm. We analyzed the implication of domestication on leaf anatomy and its effect on gm in 26 wild and 31 domesticated cotton genotypes (Gossypium sp.

View Article and Find Full Text PDF

In the natural state, the concentration of carbon dioxide in the atmosphere is about 300 μmol mol. Plants need a suitable balance of CO to achieve optimal growth. The optimum CO content corresponding to a high photosynthesis rate is between 0.

View Article and Find Full Text PDF

Recent progress in observing sun-induced Chl fluorescence (SIF) provides an unprecedented opportunity to advance photosynthesis research in natural environments. However, we still lack an analytical framework to guide SIF studies and integration with the well-developed active fluorescence approaches. Here, we derive a set of coupled fundamental equations to describe the dynamics of SIF and its relationship with C and C photosynthesis.

View Article and Find Full Text PDF

Mesophyll conductance (g ) is one of the major determinants of photosynthetic rate, for which it has an impact on crop yield. However, the regulatory mechanisms behind the decline in g of cotton (Gossypium. spp) by drought are unclear.

View Article and Find Full Text PDF

Mesophyll conductance (gm) has been shown to affect photosynthetic capacity and thus the estimates of terrestrial carbon balance. While there have been some attempts to model gm at the leaf and larger scales, the potential contribution of gm to the photosynthesis of non-leaf green organs has not been studied. Here, we investigated the influence of gm on photosynthesis of cotton bracts and how it in turn is influenced by anatomical structures, by comparing leaf palisade and spongy mesophyll with bract tissue.

View Article and Find Full Text PDF

To clarify the influence of water deficit on the functionality of the photosynthetic apparatus of cotton plants, leaf gas exchange, chlorophyll a fluorescence, and P700 redox state were examined in field-grown cotton Gossypium hirsutum L. cv. Xinluzao 45.

View Article and Find Full Text PDF

Drought slows net photosynthetic rate (AN) but increases water use efficiency (WUE). Farmers give an artificial drought pretreatment to some crops in the early growth stage and find that yield increases accompanying with the improvement of WUE. We conducted well-watered, non-drought, mild drought and moderate drought pretreatments of potted cotton cultivars.

View Article and Find Full Text PDF