Gamete binning: chromosome-level and haplotype-resolved genome assembly enabled by high-throughput single-cell sequencing of gamete genomes

Generating chromosome-level, haplotype-resolved assemblies of heterozygous genomes remains challenging. To address this, we developed gamete binning, a method based on single-cell sequencing of haploid gametes enabling separation of the whole-genome sequencing reads into haplotype-specific reads sets. After assembling the reads of each haplotype, the contigs are scaffolded to chromosome level using a genetic map derived from the gametes. We assemble the two genomes of a diploid apricot tree based on whole-genome sequencing of 445 individual pollen grains. The two haplotype assemblies (N50: 25.5 and 25.8 Mb) feature a haplotyping precision of greater than 99% and are accurately scaffolded to chromosome-level.

Chromosome-level and haplotype-resolved genome assembly enabled by high-throughput single-cell sequencing of gamete genomes

Generating chromosome-level, haplotype-resolved assemblies of heterozygous genomes remains challenging. To address this, we developed gamete binning, a method based on single-cell sequencing of haploid gametes enabling separation of the whole-genome sequencing reads into haplotype-specific reads sets. After assembling the reads of each haplotype, the contigs are scaffolded to chromosome-level using a genetic map derived from the gametes. As a proof-of-concept, we assembled the two genomes of a diploid apricot tree based on whole-genome sequencing of 445 individual pollen grains. The two haplotype assemblies (N50: 25.5 and 25.8 Mb) featured a haplotyping precision of >99% and were accurately scaffolded to chromosome-level.

Behavioral Responses of Scolytus schevyrewi (Coleoptera: Curculionidae: Scolytinae) to Volatiles From Apricot Tree (Rosales: Rosaceae)

Scolytus schevyrewi Semenov (Coleoptera: Curculionidae: Scolytinae) is native to China and Central Asia. Damage by the adults and larvae weakens local apricot trees (Armeniaca spp.), often causing death to many host trees. In previous studies, freshly cut apricot logs were found to be highly attractive to S. schevyrewi adults. To explore the possibility of trapping and monitoring this bark beetle, we evaluated the effect of the apricot tree volatiles on S. schevyrewi behavior. Volatiles from the apricot logs were collected by headspace sampling and subjected to coupled gas chromatography-electroantennographic detection (GC-EAD) analysis. Behavioral responses to EAD-active compounds were assessed using two-choice Y-tube olfactometers. The results showed that the antennae of females responded to 21 volatile compounds from apricot logs. Seventeen compounds were confirmed with authentic compounds. The Y-olfactometer bioassays showed that at a stimulation dose of 100 µg, four compounds [(1S)-(−)-α-pinene, (±)-limonene, (1S)-(+)-3-carene, and 1-hexanol], and some binary mixtures of the four compounds [(1S)-(−)-α-pinene plus (±)-limonene; (1S)-(−)-α-pinene plus (1S)-(+)-3-carene; (1S)-(−)-α-pinene plus camphene; (1S)-(−)-α-pinene plus (±)-limonene, (1S)-(+)-3-carene, and 1-hexanol] were significantly attractive to both sexes (except (±)-limonene and (1S)-(+)-3-carene for males), suggesting that these compounds may play a role in host tree selection by S. schevyrewi and should be evaluated as lures for population monitoring. In contrast, octanal, nonanal, decanal, linalool and N,N-diethylformamide appeared to repel S. schevyrewi adults in Y-tube at the concentration tested.

Selection of Dried and Table Apricots in Nevsehir and Nigde Regions, Turkey

Apricot, for which Turkey is recognized as a top producer and the leading country in the world, is one of the most produced stone fruits in Turkey. For long time ago, apricot has been grown with the nursery plants obtained from the seeds in Nevsehir and Nigde provinces caused a wide range of germplasm resources in this area (Cappadocia area). Each apricot tree shows different characteristics and could be a variety candidate. With this study, phenological and pomological characters of 91 genotypes were determined and among them 15 of the best promising genotypes were given in this paper. Considering the experimented 15 genotypes, 8 genotypes gave higher Brix value (SSC) (27-31%) than ‘Hacihaliloglu’ variety (25-26%) which was the most common dried apricot variety in Turkey. Regarding the fruit weight, which is an important aspect for both dried and table fruits, high valued genotypes were also determined. The fruit weight of 11 genotypes were higher than 50 g with the values between 51.45 g and 84.02 g. As a result of this study, candidates for dried and table apricot genotypes were identified.

Contribution to the Energy Situation in Tajikistan by Using Residual Apricot Branches after Pruning as an Alternative Fuel

A lack of access to energy in the rural areas of Tajikistan is one of the current problems of the country. Tajikistan’s goal is to reach energy independency, and the main prospects for the country’s energy sector, which relies on energy imports during the long heating periods, are: higher exploitations of hydropower and development of other renewables, mainly biofuels. Tajikistan is a highly agrarian country, where agriculture is the dominant source of income for the majority of the population. Apricot belongs to the primary agricultural commodities; however, the cultivation and management of apricot orchards is associated with the annual accumulation of significant amounts of wood waste (residual branches after pruning), which represent a source of easily available biomass. Thus, the main focus of the present research was to investigate the properties (physical, chemical and mechanical) of densified briquettes and pellets from the residual apricot tree branches through the laboratory measurements by the standard methodologies and to calculate the energy yield and potential of this material for Tajikistan as a similar study has not been conducted yet. The results showed a good quality of apricot-based biofuels characterised by the high calorific value (NCV dry basis of 19.3 MJ kg−1), relatively low ash content (1.7%) and suitable values of the main chemical elements that fulfil the standard requirement on graded wooden biofuels. The total yearly energy yield of residual apricot branches was calculated to be 3245 TJ.