[前沿资讯] Bacillus velezensis 5113 Induced Metabolic and Molecular Reprogramming during Abiotic Stress Tolerance in Wheat 进入全文
[学术文献] Pre-harvest measures against Fusarium spp. infection and related mycotoxins implemented by Dutch wheat farmers 进入全文
Fusarium spp. are one of the most widespread mycotoxin-producing fungi in small-grain cereals like wheat. Their rate of infection and production of mycotoxins is mainly influenced by weather and pre-harvest agronomic measures. Consequently, farmers' prevention and control of mycotoxins are imperative since it is difficult to remove mycotoxins further down the cereal supply chain. This study aimed to (i) identify which pre-harvest preventive and control measures Dutch wheat farmers currently apply against Fusarium spp. infection and mycotoxin contamination and to (ii) examine which farm and farmer characteristics explain the implementation of these measures. Field data on pre-harvest measures, like the selection of resistant varieties, fungicide use, and crop rotation, along with farm and farmer characteristics were collected from Dutch wheat farmers via an online questionnaire. Probit models were applied to examine farm and farmer characteristics that explain the implementation of pre-harvest measures. Results showed that most farmers applied six or more different measures against Fusarium spp. infection and mycotoxin contamination in wheat and that the use of pre-harvest measures is related to at least one other measure. However, results indicated that about 44% of farmers could become more effective if they implemented a benchmark approach consisting of a combination of fungicide use during flowering, selection of a Fusarium resistant wheat variety, and plowing or crop rotation. Five out of the ten evaluated farm and farmer characteristics significantly (p < 0.05) explained the implementation of at least one of the eight pre-harvest control measures. These five farm and farmer characteristics include wheat as main income crop, the use of a decision support system, the education level of the farmer, the farmer's knowledge about mycotoxins, and the farmer's level of risk aversion. Insight into relevant characteristics can be used by farmer cooperatives, processing industries and government agencies to improve the overall mycotoxin management of wheat farmers.
[学术文献] Overexpression of a WRKY Transcription Factor TaWRKY2 Enhances Drought Stress Tolerance in Transgenic Wheat 进入全文
Drought is a major environmental stress that severely restricts plant growth and crop productivity. A previous study showed that TaWRKY2 from wheat (Triticum aestivum) plays an important role in drought stress tolerance. In the present study, we isolated the promoter of TaWRKY2 and identified multiple regulatory cis-elements in the promoter region. The activity of the TaWRKY2 promoter was induced by drought, salt, heat, and abscisic acid (ABA). We also generated TaWRKY2-overexpressing transgenic wheat, and found that the transgenic seedlings exhibited significantly enhanced tolerance to drought stress, as evidenced by a higher survival rate and lower water loss rate of detached leaves compared with wild type (WT) plants. In addition, the transgenic lines had higher contents of free proline, soluble sugar, and chlorophyll. During a prolonged period of drought stress before the heading stage, the growth of WT plants was inhibited, whereas the TaWRKY2-overexpressing lines progressed to the heading stage. The increased grain yield of the transgenic wheat lines reflected the cumulative effects of longer panicle length, more kernels per spike, and greater aboveground biomass. Our findings show that TaWRKY2 can enhance drought tolerance and increase grain yield in wheat, thus providing a promising candidate target for improving the drought tolerance of wheat cultivars through genetic engineering.
[学术文献] Cold Tolerance of Photosynthetic Electron Transport System Is Enhanced in Wheat Plants Grown Under Elevated CO2 进入全文
The effects of CO2 elevation on sensitivity of photosynthetic electron transport system of wheat in relation to low temperature stress are unclear. The performance of photosynthetic electron transport system and antioxidant system in chloroplasts was investigated in a temperature sensitive wheat cultivar Lianmai6 grown under the combination of low temperature (2 days at 2/−1°C in the day/night) and CO2 elevation (800 μmol l−1). It was found that CO2 elevation increased the efficiency of photosynthetic electron transport in wheat exposed to low temperature stress, which was related to the enhanced maximum quantum yield for electron transport beyond QA and the increased quantum yield for reduction of end electron acceptors at the PSI acceptor side in plants under elevated CO2. Also, under low temperature, the activities of ATPases, ascorbate peroxidase, and catalase in chloroplasts were enhanced in wheat under elevated CO2. It suggested that the cold tolerance of photosynthetic electron transport system is enhanced by CO2 elevation.