Genomic analysis provides insights into the westward expansion of domesticated peaches in China

Peach, an economically important model plant of the Rosaceae family, has been domesticated and cultivated in China for approximately5 000 years. The Hexi Corridor, an important corridor connecting east-central China and the Tarim Basin, is the starting point of the Silk Road that links China and the Eurasian region. As a globally distributed fruit tree, the spread of peach was accomplished through historical trade routes in the Hexi Corridor and the Tarim Basin. However, knowledge of peach genetic diversity in these regions remains limited. In this study,we examined the relationships and the spread history of domesticated peaches through sequencing and genomic analysis of 161 peach accessions collected from Northwest China, including 43 from the Hexi Corridor and 104 from the Tarim Basin. The results indicate that peach landraces in the Hexi Corridor and the Tarim Basin are derivatives of peaches from the east and south of China (ESC). Notably, the genetic diversity of accessions from both the Hexi Corridor and the Tarim Basin was lower than that of ESC accessions. Reduction of diversity (ROD) and linkage disequilibrium (LD) analyses detected a genetic bottleneck in peaches from these regions. Additionally, these peaches have undergone varying degrees of selection from natural environment. Moreover, genes responsive to biotic and abiotic stresses were under selection, which could be the result of the climate change of Northwest China after the Last Glacial Maximum (LGM). Our findings provide a better understanding of the genetic basis of peach migration in Northwest China. Furthermore, this study expands the available genomic data for peaches and provides critical information for future peach breeding programs.

Peculiarity of transcriptional and H3K27me3 dynamics during peach bud dormancy

Bud dormancy facilitates the survival of meristems under harsh environmental conditions.To elucidate how molecular responses to chilling accumulation controlling dormancy in peach buds,chromatin immunoprecipitation sequencing to identify the H3K27me3 modifications and RNA sequencing of two peach cultivars with pronounced differences in chilling requirement were carried out,the results showed that genes associated with abscisic acid and gibberellic acid signal pathways play key roles in dormancy regulation.The results demonstrated that peach flower bud differentiation occurred continuously in both cultivars during chilling accumulation,which was correlated with the transcript abundance of key genes involved in phytohormone metabolism and flower bud development under adverse conditions.The more increased strength in high chillingrequirement cultivar along with the chilling accumulation at the genome-wide level.The function of the dormancy-associated MADS-box gene PpDAM6 was identified,which is involved in leaf bud break in peach and flower development in transgenic Nicotiana tabacum(NC89).In addition,PpDAM6 was positively regulated by PpCBF,and the genes of putative dormancy-related and associated with metabolic pathways were proposed.Taken together,these results constituted a theoretical basis for elucidating the regulation of peach bud dormancy transition.

Characteristics of Ambient Air Quality in the Central Urban Area of Western Guizhou in the Past Five Years

Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become one of the main problems that endanger human health and restrict economic development,which has been widely concerned.In this paper,the air quality status and its changing trend were analyzed by using the methods of the comprehensive index of ambient air quality and Spearman s rank correlation coefficient,based on the hourly pollutant concentration data of five national ambient air quality monitoring stations in the central urban area of Liupanshui City,Guizhou Province from January 1,2015 to December 31,2019.The results showed that the concentration of air pollutants in the atmosphere in the past five years showed a downward trend in the central urban area of Liupanshui City.During 2018-2019,the air quality has been up to the standard for two consecutive years,and it was developing to a higher quality direction.The air quality was better in summer half year than in winter half year.In one year,the air quality was the best in June and the worst in February.The air quality was the best at 07:00 and the worst at 21:00 every day.The air quality in the east and the west of the city was better than that in the middle.In most years,the activities,making and burning paper to resemble money as an offering sacrifices to gods or ancestors in Zhongyuan Festival,caused serious pollution.

An Automatic Monitoring and Alarming Method for the Power Supply of Weather Radars

As weather radar stations require headroom environment to operate,they were mostly built on highlands which are usually unattended.The mains supply is relatively poor,and the risk of radar stoppages due to power outage is therefore ever-present.As such,the radar construction program is used to build a complementary security video monitoring system.By collecting monitoring images of the regulated power supply in real-time from power supply auto transfer systems in distribution rooms and radar transceiver rooms,using Spearman’s rank correlation coefficient to analyse pixel variation trends,and supplementing statistical analysis of pixel characteristics difference to eliminate misjudgments resulting from low image contrast in special scenarios,a software can be developed through C#.It has the function of automatically monitoring mains supply and alerting staff on duty to handle the power outage in a timely manner via text message so that any potential risk is neutralised before it can cause damage.This monitoring and auto-alerting approach is generally applicable to unattended rooms with large amounts of electronical equipment.

Air Pollution Characteristics and Cause Analysis of Main Urban Area of Western Guizhou in the Ghost Festival

According to the air quality monitoring and meteorological observation data from 2015 to 2020,the air pollution characteristics and causes were analyzed in the Ghost Festival(on the 15 th of the 7 th lunar month)for the main urban area of Liupanshui City in western Guizhou Province.The results showed that air pollution to different extent occurred in the Ghost Festival every year,reaching the level of heavy pollution in half of the year.The pollution time is generally from 21:00 on the day to 01:00 on the next day.The pollutants mainly come from the smoke dust generated by people burning sacrificial offerings and industrial pollution of iron and steel manufacturing under adverse weather conditions.The primary pollutant is PM 2.5,and the annual variation of pollution shows a downward trend.Precipitation weather is in the majority,which is favorable for reducing the pollution degree;the relationship between wind direction,wind speed and pollution degree is closed;the atmospheric inversion is weak,which has no obvious influence on the change of air pollution;the relative humidity is high,which is conducive to the formation and maintenance of pollution;there is a very significant negative correlation between the degree of air pollution and wind energy,and significantly negative correlation between the degree of air pollution and atmospheric turbulence intensity.Advocating civilized sacrifice and strengthening management is beneficial to reducing the degree of pollution.This paper can be used as a reference for air quality forecasts and taking the appropriate measures to reduce pollution.