Crop Design最新文献

Bakanae disease, mainly caused by Fusarium fujikuroi, can lead to yield losses ranging from 10 to 20%. The lack of systematic researches on efficient propagation of pathogenic F. fujikuroi, artificial inoculation technology and the pathogenic conditions presents a critical technological gap that has severely hampered research on rice resistance to bakanae disease. This study first explored the sporulation conditions of F. fujikuroi in mung bean liquid medium, and determined that F. fujikuroi cultured in 40 ​g/L mung bean liquid medium for 2–6 days could efficiently produce pathogenic spores in large quantity. On this basis, we further establish an artificial inoculation system to induce bakanae disease. The main steps and parameters include: Soak rice seeds in a F. fujikuroi spore solution with a concentration of 1 ​× ​10⁶ conidia/mL for 2 days; let imbibed seeds germinate, and choose germinating seeds with buds of a grain length and cultivate them on half strength MS medium (1/2 MS, pH 5.8–6.8) for about a week. The characteristic bakanae symptoms of excessively elongated seedlings could thus be induced. Furthermore, we found that the bakanae disease symptoms became more profound when a small amount of PDA (0.5%) was added to 1/2 MS medium. Hence our study established a technical system for the artificial induction of bakanae disease involving the use of mung bean medium for rapid propagation of F. fujikuroi spores, seed inoculation and cultivation of seedlings in 1/2 MS medium added with 0.5% PDA. This system will enable quick assessment of bakanae disease resistance and thus will be useful for rice breeding.

To feed 10 billion people in 30 years from now will heavily depend on new higher yield, yet safe, biotech crop varieties, which are developed using biotechnologies, particularly genetic transformation and genome editing. A clean transgenic plant (CTP) contains only the defined transgene, whilst a clean edited plant (CEP) is transgene-free. Currently, it is difficult and time-consuming to identify and locate transgenes within plant genomes due to the complex nature of transfer DNA (T-DNA) or plasmid backbone integration, which has led to a major obstacle in mass scale production of clean transgenic/edited plants (CTREPs). Here we have built a web-based portal, CTREP-finder, for fast detection, characterization and visualization of foreign DNA fragments in plants, based on next-generation whole genome sequencing data. We invented a novel bioinformatics strategy to handle three scenarios of transgene integration and successfully identified CTREPs by testing 132 samples. Furthermore, we compared the CTREP-finder with three public programs, FED, transgeneR and TDNAscan, and it showed that the CTREP-finder outperforms those programs particularly on the localization of transgene integration. The use of CTREP-finder needs little requirement for bioinformatics expertise. Therefore, it is a user-friendly web-based portal that could be used by plant breeders and regulatory agencies for the rapid selection/detection of CTREPs for crop breeding and production.

Nanotechnology is an important driver leading to the revolution in the fields of agriculture. Here, we presented insights into the application of carbon nanomaterials (single- and multi-walled carbon nanotubes and graphene) in biomolecule delivery for crop breeding. We also reviewed the application of graphene to biosensors and the utilization efficiency of water, fertilizers and insecticides in agriculture to better manage environmental stresses. Finally, potential molecular interaction mechanisms between graphene and plant roots were discussed. It can be expected that carbon nanomaterials will hold strong promise in developing a more efficient agricultural production system.

Allotetraploid Gossypium hirsutum and G. barbadense are two major cultivated cotton species that have different fiber traits. Research into the molecular basis of those differences is limited by a lack of accurate, complete transcript profiles. Here we adopted joint PacBio Iso-seq and RNA-seq to investigate genome-wide transcript profiles and uncover differences in the expression between G. hirsutum acc. TM-1 and G. barbadense cv. Hai7124. We obtained 178,867 full-length transcripts covering 60.0% of gene loci in the TM-1 reference annotation, including 7846 transcription factors and 3122 lncRNAs. Moreover, we identified 304 and 610 high-confidence (HC) species-specific transcripts in TM-1 and Hai7124, respectively, along with 4156 and 4381 tissue-specific transcripts. Our results update the reference genome annotation and also provide potential resources for studying the molecular mechanisms of fiber development. We are thus able to promote improvements in cotton fiber quality.

Climate changes threaten global sustainable food supply by reducing crop yield. Estimates of future crop production under climate change have rarely considered the capacity of genetic improvement in breeding high-yielding and stress-tolerant crop varieties. We believe that technological advancements and developing climate-resilient crop varieties may offset the adverse effects of climate change. In this study, we examined the historical record of barley breeding and yield, and the trends of climate changes over the past 70 years in Australia. We related the selection of fast development varieties to yield improvement, and revealed the genetic connections of fast development and yield potential through genome-wide association studies. Historical records show that Australia's barley yield has experienced a steady growth despite that the seasonal production window has been shortened due to increased risk of frost damage at flowering stage and terminal heat during maturity since the 1970s. The increase in yield is largely the result of higher yield capacity of the more recently developed varieties that develop faster to counteract the impact of increased terminal heat. We also show that the changing temperature may soon reach a critical point that dramatically changes the barley flowering behaviour to impact yield by pushing its growth beyond the seasonal production window to face increasing frost damage. For the first time, we provide evidence that the effects of climate change on crop production might be less severe than what is currently believed because the advancement of technologies and development of climate-resilient crop varieties may mitigate the adverse effect of climate change to some extent. The greater use of genetic techniques in crop breeding will play a vital role in sustainable global food production in the era of climate change.