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Rice is an important global crop and represents a vital source of calories for many food insecure regions. Efforts to improve this crop by improving yield, nutritional content, stress tolerance, or resilience to climate change are certain to include biotechnological approaches, which rely on the expression of transgenes in planta. The throughput and cost of currently available transgenic expression systems is frequently incompatible with modern, high‐throughput molecular cloning methods. Here, we present a protocol for isolating high yields of green rice protoplasts and for PEG‐mediated transformation of isolated protoplasts. Factors affecting transformation efficiency were investigated, and the resulting protocol is fast, cheap, robust, high‐throughput, and does not require specialist equipment. When coupled to a high‐throughput modular cloning system such as Golden Gate, this transient expression system provides a valuable resource to help break the "design‐build‐test" bottleneck by permitting the rapid screening of large numbers of transgenic expression cassettes prior to stable plant transformation. We used this system to rapidly assess the expression level, subcellular localisation, and protein aggregation pattern of nine single‐gene expression cassettes, which represent the essential component parts of the β‐cyanobacterial carboxysome. We provide a protocol for the transient expression of transgenes in rice protoplasts. The method is simple, inexpensive, confers a high efficiency of transformation, and is high‐throughput, thus permitting its use in combination with high‐throughput cloning methods. We demonstrate its utility in assessing the localisation of various cyanobacterial proteins. [ABSTRACT FROM AUTHOR]

Abstract Crop production is expected to increase by more than 50% to meet the demand of population growth in China in 2050 (FAO, 2017). Crop production in North China largely depends on irrigation, which is mainly from groundwater in Northwest China. Over-extraction of groundwater is decreasing groundwater levels, and threatening the fragile ecological systems of arid regions. How groundwater levels will change in order to meet the irrigation water requirement in Northwest China has not been extensively investigated to evaluate sustainability of agriculture and the cost to maintain groundwater levels. Here, we examine the dynamic relations between groundwater levels and the amount of irrigation water, by employing the Variable Infiltration Capacity model and an irrigation scheme, for the last three decades in Heihe River basin of China. The results show that on the average about 1.86 m decline of groundwater is attributable to the irrigation water consumption for the farmland area in Heihe River over the past three decades. In the scenario of ceasing irrigation activities, the groundwater level will be prevented to further decline about 3.06 ± 0.4 m under the future climate scenarios till 2050, but at the cost of crop production valued 64.2 ± 8.4 billion CNY. Effective water-saving measures and strategies are expected to adopt to maintain both groundwater levels and agricultural productivity for the coming decades. Highlights • The production sustainability on irrigation water in the Heihe Oasis are assessed. • The groundwater level (GWL) declines attributed to crop production are examined. • The cost we need to pay for ceasing GWL declines in farmland region is quantified. [ABSTRACT FROM AUTHOR]

Abstract: In order to identify genotypes of durum wheat expressing improved yield and determining whether selection for individual plant efficiency in producing grains would improve plant and crop yield, we firstly compared the performance of segregating mutants and control cultivars and then selected divergent lines for number of grains per unit stem length, representing extreme source-sink balances further characterising the offspring lines. Research included three field experiments with individual segregating plants within the semi-arid region of the Ebro Valley during the 2006/07, 07/08 and 08/09 growing seasons; a fourth experiment with segregating plants conducted under controlled conditions at Rothamsted in 2008/09 and finally a conventional field plot experiment with the most promising lines derived from the selection. In the initial characterization of the selected mutants, there was a clear response to the selection made in M2, and differences in plant yield were due to differences in grains per plant and biomass. There was a clear response to selection for sink-strength in improving the number of grains exhibited by the offspring lines through the generations (M2–M5) and the overall differences between the two divergent groups were consistently clear throughout the whole process. Response to selection was similarly expressed in field and in controlled conditions, implying high broad sense heritability of grains per plant (when there were no consistent differences in height and then it reflects grains per unit stem length). The best selections outyielded plants of the controls, without reducing the protein concentration of the grains. It seems clear that increasing the efficiency of conversion of growth during stem elongation into grains may be a relevant trait to further raise yield and that the trait used in the present study as a proxy of such efficiency (the number of grains per unit stem length) seemed appropriate as a selection criteria in early generations as it expressed similarly in isolated plants and in crop stands. [Copyright &y& Elsevier]

Depending on how the future will unfold, today's progress in biotechnology research has greater or lesser potential to be the basis of subsequent innovation. Tracking progress against indicators for different future scenarios will help to focus, emphasize, or de-emphasize discovery research in a timely manner and to maximize the chance for successful innovation. In this paper, we show how learning scenarios with a 2050 time horizon help to recognize the implications of political and societal developments on the innovation potential of ongoing biotechnological research. We also propose a model to further increase open innovation between academia and the biotechnology value chain to help fundamental research explore discovery fields that have a greater chance to be valuable for applied research. Identifying most relevant social, economic, and technological trends can help us understand in which direction future worlds could develop. Extrapolating long-term impact of current developments on the way we live may open avenues of biotechnology discovery research that would provide the starting basis for research and innovation addressing future needs. Maximizing innovation output in biotechnology requires a continuous cross-stakeholder interaction to timely share know–how obtained from discovery research in formats tailored to stakeholder use requirements [ABSTRACT FROM AUTHOR]

Improving photosynthesis is a major target for increasing crop yields and ensuring food security. Phenotyping of photosynthesis in the field is critical to understand the limits to crop performance in agricultural settings. Yet, detailed phenotyping of photosynthetic traits is relatively scarce in field-grown wheat, with previous studies focusing on narrow germplasm selections. Flag leaf photosynthetic traits, crop development, and yield traits were compared in 64 field-grown wheat cultivars in the UK. Pre-anthesis and post-anthesis photosynthetic traits correlated significantly and positively with grain yield and harvest index (HI). These traits included net CO2 assimilation measured at ambient CO2 concentrations and a range of photosynthetic photon flux densities, and traits associated with the light response of photosynthesis. In most cultivars, photosynthesis decreased post-anthesis compared with pre-anthesis, and this was associated with decreased Rubisco activity and abundance. Heritability of photosynthetic traits suggests that phenotypic variation can be used to inform breeding programmes. Specific cultivars were identified with traits relevant to breeding for increased crop yields in the UK: pre-anthesis photosynthesis, post-anthesis photosynthesis, light response of photosynthesis, and Rubisco amounts. The results indicate that flag leaf longevity and operating photosynthetic activity in the canopy can be further exploited to maximize grain filling in UK bread wheat. [ABSTRACT FROM AUTHOR]

Photosynthesis in C3 plants is limited by features of the carbon-fixing enzyme Rubisco, which exhibits a low turnover rate and can react with O2 instead of CO2, leading to photorespiration. In cyanobacteria, bacterial microcompartments, known as carboxysomes, improve the efficiency of photosynthesis by concentrating CO2 near the enzyme Rubisco. Cyanobacterial Rubisco enzymes are faster than those of C3 plants, though they have lower specificity toward CO2 than the land plant enzyme. Replacement of land plant Rubisco by faster bacterial variants with lower CO2 specificity will improve photosynthesis only if a microcompartment capable of concentrating CO2 can also be installed into the chloroplast. We review current information about cyanobacterial microcompartments and carbon-concentrating mechanisms, plant transformation strategies, replacement of Rubisco in a model C3 plant with cyanobacterial Rubisco and progress toward synthesizing a carboxysome in chloroplasts. [ABSTRACT FROM AUTHOR]

Abstract: Plants produce various compounds in response to water deficit. Here, the presence and identification of a drought-inducible non-protein amino acid in the leaves of two C4 grasses is first reported. The soluble amino acids extracted from the leaves of three different species were measured by high-performance liquid chromatography of derivatives formed with o-phthaldialdehyde and β-mercaptoethanol. One amino acid that increased in amount with drought stress had a retention time not corresponding to any common amino acid. Its identity was determined by metabolite profiling, using 1H NMR and GC–MS. This unusual amino acid was present in the dehydrated leaves of Cynodon dactylon (L.) Pers. and Zoysia japonica Steudel, but was absent from Paspalum dilatatum Poir. Its identity as 2-amino-5-hydroxypentanoic acid (5-hydroxynorvaline, 5-HNV) was confirmed by synthesis and co-chromatography of synthetic and naturally occurring compounds. The amount of 5-HNV in leaves of the more drought tolerant C4 grasses, C. dactylon and Z. japonica, increased with increasing water deficit; therefore, any benefits from this unusual non-protein amino acid for drought resistance should be further explored. [Copyright &y& Elsevier]

The specificity factor of Rubisco is a measure of the relative capacities of the enzyme to catalyse carboxylation and oxygenation of ribulose 1,5-bisphosphate and hence to control the relative rates of photosynthetic carbon assimilation and photorespiration. Specificity factors of purified Rubisco from 24 species of C3 plants found in diverse habitats with a wide range of environmental growth limitations by both water availability and temperature in the Balearic Islands were measured at 25 °C. The results suggest that specificity factors are more dependent on environmental pressure than on phylogenetic factors. Irrespective of phylogenetic relationships, higher specificity factors were found in species characteristically growing in dryer environments and in species that are hemideciduous or evergreen. Effects of temperature on specificity factor of the purified enzyme from 14 species were consistent with the concept that higher specificity factors were associated with an increase in the activation energy for oxygenation compared to carboxylation of the 2,3-enediolate of RuBP to the respective transition state intermediates. The results are discussed in terms of selection pressures leading to the differences in specificity factors and the value of the observations for identifying useful genetic manipulation to change Rubisco polypeptide subunits. [ABSTRACT FROM AUTHOR]

Analyzes the biosynthesis of 2-carboxyarabinitol 1-phosphate through reduce expression of chloroplastic fructose 1,6-bisphosphate phosphatase and radiotracer studies. Assimilation of carbon dioxide during photosynthesis; Structural similarity between branch-chain sugar phosphate; Accumulation of hamamelose in plants.

Examines the trypsin cleavage by purified ribulose 1,5-biphosphate carboxylase/oxygenase (Rubisco). Effects on the loss of carboxylase activity by carboxypeptidase; Susceptibility of Rubisco to protease; Quantification of catalytic sites capable of binding.

Describes the genetic transformation of elite wheat varieties Cadenza and Canon through particle bombardment. Research on wheat genetic transformation; Role of high embryogenic capacities on the high regeneration frequencies of both wheat varieties; Correlation between transformation frequency and the age of wheat donor plants; Age of plants when most of the available embryos are of suitable size.