Saturday, August 10, 2024

Unlocking the potential of rapeseed: CRISPR edits for hybrid efficiency

GEE I THOUGHT MONSANTO (C) (R) (TD) CANOLA WAS ALREADY GMO



Nanjing Agricultural University The Academy of Science
Phenotypic characterization of flower buds, open flowers, and silique development in WT and four mutants. 

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Phenotypic characterization of flower buds, open flowers, and silique development in WT and four mutants. A The growth and flowering of the WT and four mutants. Blue arrows indicate normally developed flower buds and opening flowers, while white arrows highlight abnormally developed flower buds and flowers. Scale bar = 5 cm. B Flower buds, buds without sepals and petals, and anthers in flower buds before flowering. Scale bar = 0.5 cm; dashed box scale bar = 0.25 cm. C Open flowers without sepals and petals, and anthers in fully opened flowers. Scale bar = 0.5 cm; dashed box scale bar = 0.25 cm. D Siliques at 12 DAP of WT and the four mutants. Scale bar = 2 cm. EF Paraffin sections of transverse anther in flower buds 1–2 days before flowering in WT (E) and DM (L1) (F). Epidermis (ep), endothecium (en), stomium (st), connective (c), vascular bundle (v), and pollen grains (p). Scale bar = 1 mm. G Pollen viability of WT, L1, L2, L3, and L4 assessed after 5 h of room temperature staining with Alexander’s staining solution. Values in the bars represent means of three biological replicates, and error bars indicate standard deviations. Different lowercase letters above the bars indicate statistical significance at P < 0.05 based on Student’s t-test.

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Credit: Horticulture Research



In a transformative advance for agriculture, scientists have utilized CRISPR/Cas9 technology to develop a male-sterile line in rapeseed. This innovation simplifies the hybrid seed production process, overcoming traditional limitations and enhancing the crop's yield and sustainability. By targeting the BnDAD1 gene, the study disrupts the jasmonic acid pathway, essential for pollen development, leading to a controlled and efficient method for creating hybrids that can significantly boost vegetable oil output to meet global demands.

Hybrid production in rapeseed faces several significant challenges, primarily due to the complexities and limitations of current male sterility systems. Traditional methods often involve intricate management processes and are highly sensitive to environmental conditions, resulting in unstable and inefficient hybrid seed production. Due to these issues, there is a pressing need for a more efficient, stable, and environmentally resilient system to improve hybrid production in rapeseed, ensuring higher yields and better adaptability to varying agricultural conditions.

Researchers from Zhejiang University and Jiaxing Academy of Agricultural Sciences, publishing (DOI: 10.1093/hr/uhae139) in Horticulture Research on May 28, 2024, developed a novel approach using CRISPR/Cas9 technology. This method targets the BnDAD1 gene, creating male-sterile lines in rapeseed, thus simplifying hybrid seed production.

The study effectively disrupted the BnDAD1 gene, which plays a crucial role in the jasmonic acid biosynthesis pathway, using CRISPR/Cas9 technology. This disruption resulted in male sterility due to defects in anther dehiscence and pollen maturation in rapeseed. By applying exogenous methyl jasmonate, the researchers were able to restore fertility in the male-sterile lines, enabling the production of F1 hybrid seeds. This new two-line system offers a more straightforward and efficient method for hybrid seed production compared to traditional systems, which often face environmental stability issues. The male sterility induced by the CRISPR/Cas9 method proved to be stable and complete, independent of environmental conditions, making it a robust solution for hybrid rapeseed production. This innovative approach holds significant commercial potential, promising to enhance the efficiency and sustainability of rapeseed cultivation.

Dr. Lixi Jiang, lead researcher from Zhejiang University, stated, "Our findings present a significant advancement in rapeseed hybrid production. The use of CRISPR/Cas9 to induce male sterility simplifies the breeding process and holds great promise for enhancing rapeseed yield and sustainability."

This innovative approach can revolutionize hybrid seed production in rapeseed, providing a more efficient and stable method. The application of this technology can lead to increased yields and sustainability in rapeseed cultivation, addressing the growing global demand for vegetable oil.

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References

DOI

10.1093/hr/uhae139

Original Source URL

https://doi.org/10.1093/hr/uhae139

Funding information

This work was sponsored by the STI 2030 – Major Projects (2023ZD04008).

About Horticulture Research

Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2022. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.

 

How farmers and tech teamed up to better test crops






The Alliance of Bioversity International and the International Center for Tropical Agriculture

Citizen Science in Laos 

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The tricot approach enables farmers to test new crop varieties and improve food security in their communities.

 

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Credit: Ammaly Phengvilaysouk / CGIAR initiative on Mixed Farming Systems




For over a decade, farmers across the world have been working hand-in-hand with researchers at the Alliance of Bioversity International and CIAT and their collaborators to develop a better way to test new crop varieties and improve food security in their communities.

Food insecurity is on the rise worldwide, with 345 million people in 82 countries suffering acute food insecurity in 2022; making it more important than even to test and roll-out new crop varieties adapted to changing local conditions and in keeping with local needs and capabilities.  

But it wasn’t always so easy to get farmers and agricultural researchers on the same page: not so long ago, most crop varieties and other technologies were tested in large-scale field plots under generic conditions. This meant there was little attention paid to how weather conditions affected crop yield and there was also little interest or buy-in from farmers. 

Jacob van Etten, Principal Scientist and Director for Digital Inclusion, explains that tricot, (an abbreviation for triadic comparison of technologies) was originally developed to create a more cooperative “citizen science” focus, allowing new crop varieties to be tested directly in farmers’ fields, in the same context where they will hopefully be grown after the study.

“It’s the interaction between people and technology that drives innovation,” he says, “We are still doing methodological research on how we can design trials in a way that farmers can get out of it that they want to get out of it.”

From Citizen Science to Farm Collaborators

Brazilian scientist KauĂȘ de Sousa, a researcher at the Alliance of Bioversity International and CIAT started working with tricot back in 2016, as a data analyst for the first set of data generated in India. 

“Tricot helped to put the farmers’ fields at the center of the agricultural experimentation: unlike previous approaches, farmers’ don’t evaluate or comment in someone else plot, but in their own small plot,” de Sousa says, “This increases collaboration and makes the communication more interesting, not only to farmers and researchers, but to the whole community.” 

2024 study involved hundreds of common bean smallholder farmers from 140 villages in the Trifinio region of El Salvador, Guatemala, and Honduras, evaluated tricot; a group-based participatory variety testing approach and a control approach to evaluate the effectiveness of the different approaches. 

The study’s first author, Martina Occelliexplains that the researchers found that national programs can benefit from the cost-effective, equitable, externally valid, and scalable nature of citizen science on-farm testing approach for the goal of informing breeding programs.

“A citizen science on-farm testing approach should be used for on-farm testing and a group-based agronomy training could be delivered separately, for example to farmers who have gone through one round of citizen science on-farm testing,” she says adding that a hybrid approach would lead to fewer farmers dropping out of the trial and increase data value. 

“It would also benefit farmers through a group-based training approach,” she says.

Watch the video: https://youtu.be/GtoxXBwyrUU 

Emerging benefits from farmer-driven research 

Van Etten explains that tricot is now mature enough to start thinking about how researchers can organize farmer networks in a way that can scale and build up experience and be more famer-focused. 

“We are still doing methodological research on how we can design trials in a way that farmers can get out of it what they want to,” van Etten says, adding that if research is more farmer-driven, they can help guide the technological direction of agronomical research.

“It doesn't mean that it's an adversarial idea, it's about how to put different innovations side by side with farmers.”

Another 2024 paper, “The tricot approach: an agile framework for decentralized on-farm testing supported by citizen science. A retrospective” de Sousa, van Etten and their co-authors explained that there are still key issues to resolve, from how to sustain enthusiasm, skills and financing among the scientific, technical, and farmer communities; to making tricot participants become more representative of the gender and other socio-economic diversity found in farming communities. 

As more researchers and private extension networks start to use tricot around the world, more benefits from involving farmers are emerging. 

July 2024 study from Uganda showed that applying the tricot methodology allowed researchers to factor in not only the crop-specific information, but also the culinary preferences (like taste and cookability) of the farmers. The same researchers also explored the role of gender in crop preferences. 

 

Spectral measurements capable of estimating nutrient content of forest tree leaves



Journal of Remote Sensing



The general health of forests can be estimated by the micro- and macronutrient content of tree leaves to help inform forest management decisions in the light of climate change, species loss and other variables. Traditional methods of assessing nutrient levels in forests are expensive and labor-intensive. Researchers recently analyzed the reflected spectra from tree foliage to accurately estimate the nutrients of leaves, offering a faster, larger-scale method of assessing forest health.

 

Field methods of collecting leaf samples and then measuring foliage nutrient content in the lab are time-consuming. New, faster methods are required to estimate forest health as climate change alters growing conditions. To address this issue, a team of researchers from the University of Massachusetts and the University of Virginia analyzed reflected light (spectra) across a wide range of wavelengths from forest foliage to accurately determine the concentrations of calcium (Ca), magnesium (Mg), potassium (K), phosphorus (P), manganese (Mn), and zinc (Zn) in leaves.

 

The team published the study on June 27 in the Journal of Remote Sensing.

 

Specifically, the researchers measured reflected light at wavelengths from 400 to 2,450 nanometers (nm, 1.0 x 10-9 m) to assess nutrient concentrations. The team was able to identify the best wavelengths to measure each nutrient analyzed through a partial least squares regression (PLSR). PLSR is especially well-suited to manage highly correlated independent variables, like the individual reflectence over a continuous spectrum.

 

“The developed PLSR model predicted plant nutrients with moderate to strong accuracy for macro- and micronutrients in temperate hardwood forests of the Northeastern United States. Spectral measurements combined with wavelength selection and PLSR models can be used to quantify foliar macro- and micronutrients at regional scales and can be further improved by incorporating site geologic materials and tree genera,” said Qian Yu, associate professor in Earth, Geographic, and Climate Sciences at the University of Massachusetts-Amherst and the corresponding author of the research paper.

 

The researchers realized that their ability to accurately use spectra to determine the nutrient level of tree foliage could be significantly improved by considering the soil type in which the trees grew in. Notably, this variable is often overlooked when assessing the nutrient composition of tree leaves. The team measured the foliage nutrients Ca and P of trees in four types of soil: coarse glacial till, glaciofluvial, melt-out till and outwash. By accounting for soil type, researchers improved their PLSR nutrient analysis accuracy from R2 = 0.66 to R2 = 0.87 (an R2, or coefficient of determination, that equals 1.0 indicates that all variation observed is due to differences in the independent variable, or spectral measurements).

 

Different soils had greater and lesser effects on Ca and P. Soil had little effect on Ca concentrations, for example, but tended to affect P to a greater degree. Outwash soil also provided the most accurate predictions for both Ca and P nutrients. Critically, Ca is a limiting nutrient in forests that plays important roles in plant structure, chemical signaling and as an enzyme cofactor that changes enzyme efficiency.

 

The genus of the trees additionally affected the accuracy of foliage nutrient concentration predictions. In fact, analyzing spectral data based on tree genera improved the accuracy of nutrient predictions even better than soil composition. Tree genus improved Ca prediction accuracy from R2 = 0.66 to as high as R2 = 0.91 and R2 = 0.93 for Fagus (Beech) and Quercus (Oak) genera, respectively. The team analyzed spectral data for Acer (Maple) and Betula (Birch) genera as well.

 

The research team suggests that specific tree genera likely influence foliage nutrients because the physiological mechanisms responsible for nutrient acquisition and transport are genetically controlled and unique to each genus. Additionally, some tree genera may require individual nutrients more than other genera that may be more adapted to a particular soil, resulting in differences in nutrient uptake.

 

Ultimately, the research team is hopeful that their new spectral assessment technique will be successfully applied to other hardwood forests to inform important forest management decisions. “The method introduced in this paper holds promise for large-scale plant nutrient assessment and can decrease the costs of traditional, field-based approaches,” said Wenxiu Teng, Ph.D. candidate in Earth, Geographic, and Climate Sciences at the University of Massachusetts-Amherst and first author of the paper.

 

Other contributors to this research include Justin B. Richardson and Alexandrea M. Rice from the Department of Environmental Sciences at the University of Virginia in Charlottesville and Ivan C. Mischenko from the Department of Earth, Geographic, and Climate Sciences at the University of Massachusetts in Amherst and.

 

This research was supported by the University of Massachusetts Amherst, College of Natural Sciences by Award 1801.

 

High nitrogen input promotes the redistribution of new organic carbon to deeper soil layers




Higher Education Press
Fig 1 

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Fig 1

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Credit: Hualing HU, Liang ZHAO, Wenbing TAN , Guoan WANG, Beidou XI




Exogenous reactive nitrogen input has a profound effect on the carbon cycle of terrestrial ecosystems. Most current research on soil organic carbon (SOC) dynamics in relation to nitrogen input has focused predominantly on the surface soil layers. However, studies limited to the surface layer cannot fully reveal the complete response of SOC to nitrogen input because approximately half of the SOC is stored in deeper soil layers. Given the unique environmental conditions of deep soils, microbial decomposition and stabilization of deep SOC may respond differently compared to surface soils. Moreover, surface-only studies have not addressed whether nitrogen input affects the vertical migration of SOC, thereby influencing the distribution of newly absorbed carbon throughout the entire soil profile. Consequently, conducting whole-profile soil studies is essential for accurately predicting SOC exchange with the atmosphere in response to nitrogen input.

A research team led by Dr. Wenbing Tan from the Chinese Research Academy of Environmental Sciences conducted a long-term field experiment at an agricultural site, collecting soil samples from plots with varying nitrogen fertilizer treatments. By analyzing stable carbon isotopes, the team investigated the contributions of new versus old carbon to SOC and aimed to elucidate the role of soil depth in this context. Additionally, the team integrated physical and chemical soil properties with the vertical distribution of organic carbon and nitrogen to explore the mechanisms of SOC dynamics in response to different rates of nitrogen fertilizer application in deep soils.

The study revealed that SOC increased significantly with nitrogen fertilizer application, with the extent of this increase depending on the amount of nitrogen applied. Compared to low nitrogen fertilizer addition, high nitrogen fertilizer application significantly enhanced SOC sequestration primarily through reduced tillage and the return of crop residues to the field. The study observed notable differences in SOC turnover rates under different nitrogen levels. Under low nitrogen conditions, the SOC turnover time in the 0–20 cm soil layer was approximately 20–40 years, whereas under high nitrogen conditions, the SOC turnover time in the 10–20 cm soil layer extended up to 100 years. High nitrogen fertilizer application mainly increased SOC sequestration by transferring organic matter from the surface to more stable deep soil layers. Due to the high turnover rate of new organic carbon in deep soils under low nitrogen conditions, the carbon sequestration capacity of SOC in deep soils was less compared to that under high nitrogen conditions.

The results support the notion that reduced microbial decomposition rates of SOC under high nitrogen input conditions are a key mechanism for enhancing soil carbon sink functions. More importantly, the research team confirmed that the increased soil carbon sink strength under high nitrogen enrichment conditions is primarily due to enhanced vertical transport of soil organic matter, leading to a greater distribution of new organic carbon in deeper soil layers. This new mechanism offers a significant explanation for the enhancement of soil carbon storage. Future research should further define the exact impact range of this new mechanism under different nitrogen application levels and explore the applicability of these findings across various terrestrial ecosystems.

This study has been published on the Journal of Frontiers of Agricultural Science and Engineering on 2024, Vol. 11, No. 2. DOI: 10.15302/J-FASE-2024565.

 

Early mammals lived longer



University of Bonn researchers are studying the lifespan and growth patterns of early mammals



University of Bonn

Life reconstruction of two coexisting species from the Late Jurassic period in Portugal, showing aspects of their life history 

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On the left is a parent of the early mammal Dryolestes which raises a brood after reaching sexual maturity at age four. On the right is a Haldanodon, a member of the family of mammal-like docodonts, before fully reaching the mammalian evolutionary level; the creature's lifespan was eleven to fourteen years.

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Credit: © Image: James Brown/©Pam Gill.





What distinguishes the growth and development patterns of early mammals of the Jurassic period? This is the question jointly investigated by researchers of Queen Mary University of London and the University of Bonn. Paleontologists have been able to gauge the lifespan and growth rates of these ancient animals, and even when they reached sexual maturity, by studying growth rings in fossilized tooth roots. The study has now been published in the journal Science Advances. Don´t publish before 8 pm CET on Wednesday, August 7!

“Never before have we been able to reconstruct the growth patterns of these early mammals in such detail,” says lead author Dr. Elis Newham, a postdoc at Queen Mary University of London who during the study was an Alexander von Humboldt Research Fellow at the University of Bonn, up to March 31, 2024.

For the study, the team analyzed fossilized tooth roots of mammal species from the Early to Late Jurassic periods (200-150 million years ago) found at three separate sites. The finds made in Wales are of some of the oldest known mammalian precursors from the Early Jurassic period, while the fossils found in Oxfordshire, UK are of a very broad array of coexisting early mammals. The fossils from the third site in Portugal date from the Late Jurassic.

Fossil tooth roots X-rayed

The research team studied the fossils using a technique called synchrotron X-ray tomography in which electrons are accelerated to near light speed (unlike regular X-ray imaging). The technique affords several advantages, starting with the fact that the fossils no longer have to be prepared, i.e. cut up into slices, so they can be analyzed whole. Furthermore, images obtained via synchrotron X-ray tomography are of higher quality than images from conventional X-ray microtomography.

Researchers were able to image tiny growth rings in fossilized root cement—the bone tissue that attaches the teeth to the jaw. “The rings are similar to those in trees, but on a microscopic level,” explains Professor Thomas Martin of the Vertebrates – Mammals working group at the University of Bonn Institute of Organismic Biology, who is a senior author of the study. “Counting the rings and analyzing their thickness and texture enabled us to reconstruct the growth patterns and lifespans of these extinct animals.”

The researchers determined that the first signs of the growth patterns characteristic of modern mammals, such as a puberty growth spurt, started emerging roughly 150 million years ago. Early mammals grew much more slowly but lived substantially longer than today’s small mammals, with lifespans of eight to fourteen years instead of just one or two as in modern mice, for example. However, it took early mammals years to reach sexual maturity, again in contrast to their modern descendants which reach sexual maturity in just a few months.

“Our findings suggest that the distinctive life history patterns of mammals, characterized by high metabolic rates and extended parental care phases for example, have evolved over millions of years,” Dr. Elis Newham explains, “The Jurassic period appears to have been a crucial time for this shift.”

Sponsorship

In addition to Queens University of London and the University of Bonn, the study partners included the University of Helsinki, the Geological Survey of Finland, the Natural History Museum (UK), the University of Hull (UK), the European Synchrotron Radiation Facility (France), the University of Southampton (UK), the College of Osteopathic Medicine (USA), the University of Bristol (UK), and the University of Edinburgh (UK).

The study was made possible by funding under the European Community Seventh Framework Programme, Engineering and Physical Sciences Research Council studentships, an Alexander von Humboldt Research Fellowship for Dr. Elis Newham, the Paul Scherrer Institute, the Academy of Finland, Gingko Investments LTD and Versus Arthritis Grant 23115.

Fossil jaw of an early mammal with complete tooth row, prepared for scanning in the synchrotron.

Credit

Photo: Elis Newham

 

Rising nighttime temperatures disrupt plant metabolism: a review calls for adaptive strategies



Maximum Academic Press
Fig.1 

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High night temperature interrupts carbon balance between photosynthesis and respiration, causing a carbon deficit in plants. The upward arrows indicate increase or promotion, and downward arrows indicate decrease or inhibition.

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Credit: The authors




A research team has reviewed the detrimental effects of high nighttime temperatures (HNT) on temperate plant species, highlighting disruptions in physiological and metabolic processes such as carbohydrate, amino acid, and hormone metabolism. HNT accelerates leaf senescence, disrupts cellular membranes, and increases respiration rates, leading to the loss of carbon and carbon deficits within plant tissues. This review emphasizes the need for further research to uncover the key metabolic pathways and molecular mechanisms involved in plant adaptation to HNT, aiming to inform genetic modifications, breeding strategies, and improved management practices to enhance plant resilience.

Global warming, particularly the faster rise in nighttime temperatures compared to daytime temperatures, adversely affects plant growth and development. Current research shows that elevated HNT hinder plant productivity, with significant yield losses observed in crops like rice and wheat. However, the mechanisms behind these inhibitory effects, particularly regarding physiological and metabolic processes, are not well understood.

A study (DOI: 10.48130/grares-0024-0013) published in Grass Research on 04 July 2024, highlights the need to investigate how HNT affects carbon, amino acid, and hormone metabolism to develop strategies for mitigating its adverse impacts on plant productivity.

Researchers review the current state of research, revealing that high HNT disrupts critical physiological processes, including photosynthesis and respiration, which control carbon balance and availability. HNT accelerates leaf senescence, reduces chlorophyll content, and damages chloroplasts, leading to a significant decline in photosynthetic efficiency. Enhanced respiration rates at night consume more carbohydrates, exacerbating carbon deficits and reducing overall plant productivity. Additionally, HNT impacts amino acid metabolism, causing a variable response among different amino acids, and increases the production of reactive oxygen species (ROS), leading to oxidative damage of Rubisco. Hormone metabolism is also affected by HNT, with a decrease in growth-promoting hormones like cytokinins and auxins, and an increase in stress-related hormones such as abscisic acid (ABA) and salicylic acid (SA). This review highlights the urgent need for further investigation into how plants adapt to HNT, aiming to develop genetic modifications, breeding strategies, and improved management practices to enhance plant resilience and productivity in the face of rising nighttime temperatures.

According to the study's lead researcher, Bingru Huang, “The mechanisms of how plants can adapt to this stress remain largely unknown, particularly the key metabolic pathways and molecular factors or networks. Further research addressing these unknown aspects is critically important for improving plant resilience against warmer nights, particularly through genetic modification and breeding efforts, as well as management practices.”

In summary, nighttime temperatures are rising faster than daytime temperatures, adversely affecting temperate plant species by disrupting photosynthesis, accelerating leaf senescence, and increasing respiration rates, leading to carbon deficits. HNT also alters amino acid and hormone metabolism, with stress-related hormones increasing and growth-promoting hormones decreasing. Understanding the precise metabolic pathways and molecular mechanisms of plant adaptation to HNT is crucial. Future research should focus on developing genetic modifications, breeding strategies, and management practices to enhance plant resilience to warmer nights.

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References

DOI

10.48130/grares-0024-0013

Original Source URL

https://doi.org/10.48130/grares-0024-0013

Funding information

This work was supported by the Rutgers Center for Turfgrass Science.

About Grass Research

Grass Research (e-ISSN 2769-1675) is an open access, online-only journal focused on mechanistic aspects of biology of grasses with broad international and disciplinary interests. Research papers and review articles published in Grass Research represent significant advances in the mechanistic understanding of the genetic, genomic, molecular, cellular, biochemical, and physiological processes and pathways involved in plant growth and development, as well as interactions with the environment and other organisms, and cultural management practices. Original research and review articles will also cover the development and application of new emerging methodologies and technologies in plant biology, such as gene editing, "Omics", non-invasive imaging, remote sensing, and artificial intelligence and machine learning technologies. Grass Research also publishes editorials and perspectives for expressing opinions on a specific issue or novel insights about existing research on a particular topic.