To solve the problem of query restriction in supply‐chain financial blockchain system, this paper proposes a privacy budget management and noise reusing method in multichain blockchain environment based on Hyperledger multichannel technology and community clustering algorithm. A historical record book is established to manage the privacy budget according to historical query types, and a differential privacy protection algorithm based on noise reusing is used to generate and reusing noise. In the experiments, we tested the privacy budget loss, data utility and system performance based on the business data‐set from chemical supply chain. The experimental results show that the blockchain system with multichain structure based on community clustering algorithm reduces the system data storage space and decreases request processing time effectively. The privacy budget loss of the proposed method is about 1/3 of that of the pure Gaussian mechanism method. After 100 queries, the total amount of noise is about 8% less than that of pure Gaussian mechanism. Besides that, the noise reusing algorithm reduces the loss of the privacy budget and breaks through the query limitation caused by privacy budget wasting.

No abstract

Cucumis melo L. var. agrestis Naud. belong to the genus Cucumis in the Gourd family, it is rich in oil. It can extract high quality edible oil and provide raw materials for medicine and food industry. The chloroplast genome of Cucumis melo L. was sequenced for the first time. The results showed that the chloroplast genome of Cucumis melo L. was similar to that of common melon. This study can provide a theoretical reference for breeding.Keywords Cucumis melo L. var. agrestis Naud.; Chloroplast genome; Sequencing Field Muskmelon (Cucumis melo L. var. agrestis Naud.) belongs to the Cucumis of the family Cucurbitaceae, wild weeds. A number of scholars believe that the Field Muskmelon is the wild ancestor of Chinese oriental thin skin melon (Ma, 2020a). Seeds contain a lot of fat, which can be extracted from oil and eaten. Fruit rich in medicinal ingredients such as cucurbitacin, is a potential new type of wild plant (Ma, 2020b). At present, chloroplast genome sequencing fragments can be accurately assembled, but it's still difficult to assemble a larger complete genome, nuclear genome assembly is more difficult (Anton et al., 2012). Field Muskmelon is one of the most important cash crops in the world, Chloroplast genome sequencing has been successful, Field Muskmelon chloroplast genome contains 133 genes. The total GC content of the genome was 36.9% (Zhu et al., 2016). Genetic diversity of local muskmelon varieties in vietnam using chloroplast genome analysis (Phan et al., 2010). Genomic sequence polymorphisms were used to infer diversity and genetic differentiation of cultivated melon (Katsunori et al., 2013). And elaborated the melon chloroplast genome complete sequence and its systematic significance (Hong et al., 2020). So far, the study of chloroplast genome of Field Muskmelon has not been reported. In order to understand the composition of chloroplast genome and the relationship between genes and botanical traits, to provide theoretical and technical basis for breeding genetic improvement, The experiment material, Illumina high -throughput sequencing, The chloroplast genome sequencing of Field Muskmelon was completed.

No abstract

Objective] in order to understand the difference of volatile components in fruit of hybrid between wild melon and cultivated muskmelon, to provide technical reference for breeding. [Methods] the volatile components of wild cucumis melo L., Qingmapo and Huangmapo were analyzed by HPLC and GC-MS. [Results] the volatile compounds were identified in the fruits of these three cultivars, including 46 wild species, 92 species of Qingequao, and 79 species of Huangequao. The main volatile components are esters, olefins, alcohols, alkanes and amides. And the three varieties of volatile matter are different. Squalene, a volatile substance in wild cucumis melo, is not found in the progeny varieties.[Conclusion] the total amount of volatile substances in Qingmapo vesicle was the most, and that in Huangmapo vesicle was the least. The wild muskmelon fruit is rich in squalene and limonene, which is a kind of wild muskmelon breeding resource with high botanical value.