Estimating the Global Distribution of Field Size using Crowdsourcing

There is increasing evidence that smallholder farms contribute substantially to food production globally yet spatially explicit data on agricultural field sizes are currently lacking. Automated field size delineation using remote sensing or the estimation of average farm size at subnational level using census data are two approaches that have been used. However, both have limitations, e.g. automatic field size delineation using remote sensing has not yet been implemented at a global scale while the spatial resolution is very coarse when using census data. This paper demonstrates a unique approach to quantifying and mapping agricultural field size globally using crowdsourcing. A campaign was run in June 2017 where participants were asked to visually interpret very high resolution satellite imagery from Google Maps and Bing using the Geo-Wiki application. During the campaign, participants collected field size data for 130K unique locations around the globe. Using this sample, we have produced the most accurate global field size map to date and estimated the percentage of different field sizes, ranging from very small to very large, in agricultural areas at global, continental and national levels. The results show that smallholder farms occupy up to 40% of agricultural areas globally, which means that, potentially, there are many more smallholder farms in comparison with the two different current global estimates of 12% and 24%. The global field size map and the crowdsourced data set are openly available and can be used for integrated assessment modelling, comparative studies of agricultural dynamics across different contexts, for training and validation of remote sensing field size delineation, and potential contributions to the Sustainable Development Goal of Ending hunger, achieve food security and improved nutrition and promote sustainable agriculture

Estimating the Global Distribution of Field Size using Crowdsourcing

There is increasing evidence that smallholder farms contribute substantially to food production globally yet spatially explicit data on agricultural field sizes are currently lacking. Automated field size delineation using remote sensing or the estimation of average farm size at subnational level using census data are two approaches that have been used. However, both have limitations, e.g. automatic field size delineation using remote sensing has not yet been implemented at a global scale while the spatial resolution is very coarse when using census data. This paper demonstrates a unique approach to quantifying and mapping agricultural field size globally using crowdsourcing. A campaign was run in June 2017 where participants were asked to visually interpret very high resolution satellite imagery from Google Maps and Bing using the Geo-Wiki application. During the campaign, participants collected field size data for 130K unique locations around the globe. Using this sample, we have produced the most accurate global field size map to date and estimated the percentage of different field sizes, ranging from very small to very large, in agricultural areas at global, continental and national levels. The results show that smallholder farms occupy up to 40% of agricultural areas globally, which means that, potentially, there are many more smallholder farms in comparison with the two different current global estimates of 12% and 24%. The global field size map and the crowdsourced data set are openly available and can be used for integrated assessment modelling, comparative studies of agricultural dynamics across different contexts, for training and validation of remote sensing field size delineation, and potential contributions to the Sustainable Development Goal of Ending hunger, achieve food security and improved nutrition and promote sustainable agriculture

Screening of black pepper varieties against anthracnose under nursery conditions: Screening black pepper against anthracnose

Pathogen causing anthracnose of black pepper was isolated from symptomatic leaf sample and was identified as Colletotrichum gloeosporioides on the basis of morphological, cultural and molecular characterization. Later, pot culture experiment was conducted in greenhouse (year 2020-21) to determine resistance/susceptibility of seven different black pepper varieties viz., Arakkulamunda, Doddigya, Karimunda, Malligesara, Panniyur-1, Poonjarmunda and Uddagare, against anthracnose in nursery condition. It was observed that no variety was resistant but Karimunda variety was found to be highly tolerant against the disease. Whereas, Poonjarmunda and Panniyur-1 were classified as susceptible and highly susceptible, respectively

Development and characterization of SSR markers for pomegranate (Punica granatum L.) using an enriched library

In the present work, we report the development of 11 microstallite markers (SSR) for Punica granatum. Evaluated on a set of 27 pomegranate accessions sampled in Tunisia, they displayed 25 alleles, with number of alleles per locus ranging between 1 and 4, and an observed heterozygosity from 0.037 and 0.592. This set of SSR markers can be very useful for studies dealing with genetic diversity assessment of germplasm, with cultivars/varieties fingerprinting and pedigree analysis of this economically important fruit species

Crystal Structure, Raman Spectroscopy and Optical Property Study of Mg-Doped SnO₂ Compounds for Optoelectronic Devices

Researchers have been consistently looking for new materials that can be integrated in optoelectronic and spintronic devices. In this research, we investigated the crystalline structure, Raman, and optical characteristics of Mg-doped SnO2 compounds. The solid-state reaction technique was utilized to produce polycrystalline samples of Sn1−xMgxO2 (0 ≤ x ≤ 0.10) for their potential use in optoelectronics devices. It was discovered that all the compounds were synthesized into a tetragonal rutile-type structure of SnO2. The analysis of these samples using Raman spectroscopy provided more evidence, supporting the creation of the tetragonal rutile phase of SnO2 and the successful integration of Mg ions in SnO2. The measurements of the optical properties, such as absorbance and transmittance, carried out with a UV-Vis spectrophotometer demonstrated that the optical band gap widened with the increase in the magnesium doping concentration in SnO2. In addition, it was noticed that increasing the quantity of magnesium doping concentration led to an increase in the transmittance value from 83% to 91%