Climate Smart Agriculture最新文献

Sheath blight (ShB) caused by Rhizoctonia solani Kühn is one of the most serious diseases in rice and is highly susceptible to climate and environmental influences, high humidity climate conditions combined with higher temperatures often lead to more severe occurrences of ShB. The heterotrophic R. solani and rice might compete for sugar at the border of interaction; however, the underlying mechanism remains unclear. In this study, we demonstrated that the expression level of Sugar will eventually be exported transporters (SWEETs) induction was higher in ShB susceptible varieties than in ShB resistant varieties by R. solani inoculation. Inoculation of R. solani revealed that most sweet mutants were less susceptible to ShB than the wild-type. Also, sugar transporters (STPs) gene expression was sensitive to R. solani infection. STPs were localized at the plasma membrane and transported hexose in yeast. Knockdown of STP4 increased the susceptibility of rice to ShB. Interestingly, sequence analysis identified two monosaccharide transporter genes (hereafter named RsMST). RsMSTs transported 2-deoxyglucose, a toxic glucose analog in yeast, suggesting their role as glucose transporter. Spray-induced gene silencing of RsMST1 or RsMST2 dramatically suppressed their expression level and reduced virulence of R. solani. These data suggested that R. solani might induce SWEETs to efflux sugar from the cytosol to apoplast, and STP and RsMSTs compete for sugar at the apoplast for host defense and pathogen virulence. This study provided important insights for ShB-resistant breeding in rice.

Rain-fed potato (Solanum tuberosum) fields in drylands significantly contribute to nitrous oxide (N₂O) emissions, making them an important focus of agricultural greenhouse gas research. Film mulching and ridging are key agricultural methods in potato cultivation. Investigating the impact of these methods on N₂O emissions, nitrifying/denitrifying functional genes, and microbial communities can provide a theoretical basis for soil emission reduction and more sustainable dryland agriculture. We examine the effects of flat tillage with mulching, ridge tillage with mulching, flat tillage without mulching, and ridge tillage without mulching, on potato fields under natural rainfall conditions in Wuchuan County, China. N₂O emission fluxes were monitored using a static (dark) chamber and gas chromatography. Real-time quantitative PCR (q-PCR) was used to quantify abundances of nitrifying and denitrifying bacteria related to N₂O emissions at various potato-growth stages. Illumina high-throughput sequencing was used to investigate microbial community structure by targeting 16S rRNA genes; related soil elements (soil temperatures and moisture) are analyzed. Mulching and ridging indirectly influence N₂O emissions, nitrifying/denitrifying functional gene copy numbers, and microbial community structure by altering soil temperature and moisture. Cumulative N₂O emissions and emission intensity were both consistently higher in ridge tillage with mulching during the potato-growing period. Ammonia-oxidizing archaea are the main microorganisms that control N₂O emissions, with nitrification-coupled denitrification also being an important mechanism contributing to high N₂O emissions during soil dry–wet cycles. Increased soil temperature and moisture elevated N₂O emissions and functional gene copy numbers. The combination of mulching and ridging effectively uses the characteristics of both practices, making Nitrospira the dominant genus, and significantly increases N₂O emissions.

Continuous and accurate monitoring of agricultural landscapes is crucial for understanding crop phenology and responding to climatic and anthropogenic changes. However, the widely used optical satellite remote sensing is limited by revisit cycles and weather conditions, leading to gaps in agricultural monitoring. To address these limitations, we designed and deployed a Near Surface Camera (NSCam) Network across China, and explored its application in agricultural land monitoring and achieving climate-smart agriculture (CSA). By analyzing the image data captured by the NSCam Network, we can accurately assess long-term or abrupt agricultural land changes. According to the preliminary monitoring results, integrating NSCam data with remote sensing imagery greatly enhances the temporal details and accuracy of agricultural monitoring, aiding agricultural managers in making informed decisions. The impacts of abnormal weather conditions and human activities on agricultural land, which are not captured by remote sensing imagery, can be complemented by incorporating our NSCam Network. The successful implementation of this method underscores its potential for broader application in CSA, promoting resilient and sustainable agricultural practices.

Improving smallholder farmers' adaptive capacity to climate change has become a major concern of governments and development agencies. Adaptive capacity determines the inherent ability of a system to cope with vulnerability to climate change. This paper used cross sectional survey data of 737 livestock producing households to assess determinants of adaptive capacity among Arid and Semi-Arid (ASAL) communities in Kenya. Specifically, we focused on the role of entrepreneurship orientation (risk taking, proactiveness and innovativeness) and uptake of climate smart agricultural (CSA) practices in improving adaptive capacity – a dimension which has received limited research attention. Adaptive capacity was measured using a set of indicators representing the five capitals in the Sustainable Livelihood Framework (SLF). The determinants of adaptive capacity were analyzed using fractional and censored regression models. The results revealed mixed influence of entrepreneurship orientation on adaptive capacity. While risk taking and proactiveness were positively associated with a higher adaptive capacity, innovativeness did not have any influence. Similarly, uptake of livestock CSA practices was associated with a higher level of adaptive capacity. Other factors that positively influenced adaptive capacity were age, gender, education level, diversity of income, access to extension services, credit, and collective action. The findings suggest that a strategy to promote entrepreneurial orientation, uptake of CSA, accumulation of human and financial capital would enhance livestock producers’ adaptive capacity.