Heilongjiang Academy of Agricultural Machinery Engineering

Siberian kale (Brassica napus subsp. pabularia, AACC, 2n = 38) is a distinct subspecies of B. napus, characterized by its deeply lobed leaves and primarily cultivated as a nutritious leafy vegetable. Here, we present a chromosome-level genome of Beta, a Siberian kale variety, integrating Illumina short reads, PacBio HiFi long reads, and Hi-C data. The final assembly size is 1,078.8 Mb, with a scaffold N50 of 57.5 Mb and a genome BUSCO completeness of 99.7%. 954.0 Mb (88.4%) of sequences were successfully anchored to 19 pseudo-chromosomes. The configuration of Beta genome chromosomes is consistent with the distribution of ten A subgenome and nine C subgenome chromosomes in rapeseed. In total, 98,882 protein-coding genes were predicted ab initio in the Beta genome, with an average gene length of 1,997 bp, and 90,415 (91.44%) genes were functionally annotated. Overall, the high-quality genome provides a valuable resource for bridging current knowledge gaps and offers key genetic insights into deeply lobed leaf formation and improvement of Brassica crops.

Abstract Sugar beet production demands sustainable intensification approaches to enhance both yield and quality. This study examined the effects of foliar nano-ammonium nitrate (NH 4 NO 3 ) applications on five sugar beet cultivars – JAMPOL, BTS 9830, DEL 1135, ASEEL and Raspoly – over two growing seasons in Egypt’s Nile Delta, using a split-plot randomized complete block design. Three nano-NH 4 NO 3 concentrations (0, 50 and 100 ppm) were sprayed twice each season to assess impacts on growth, yield and quality parameters. The results indicated limited influence of treatments on primary yield metrics; taproot yields remained unaffected across all cultivars and seasons. Nonetheless, the 50 ppm treatment preserved optimal sugar quality, with sucrose content reaching 19.4 %, compared to 18 % in the controls. Carotenoid levels increased by 12 % under the 100 ppm treatment, reflecting enhanced nutritional quality. Among cultivars, ASEEL yielded the best results with taproot outputs of 34 t/ha and sugar yields of 6.1 t/ha under optimal conditions, demonstrating significant cultivar-dependent variation. Multivariate analysis revealed distinct response patterns among cultivars and treatments, with three-way interactions (Season × Cultivar × Nanoparticle) affecting several traits. Clustering identified four trait groups and three treatment clusters, highlighting sugar beet’s complex response to nanoparticles. Economic analysis shows limited benefits, with no significant increase in taproot yield, despite a rise in secondary metabolites. While nano-NH 4 NO 3 can modify biochemical parameters, the lack of yield improvements casts doubt on its economic feasibility. Cultivar choice primarily influences sugar beet performance, with environmental conditions also affecting treatment efficacy.

To address the issue that existing seed-guiding devices struggle to meet the high-speed operational requirements of delta-row planters for dense maize planting, a seed-guiding device with air assistance and a guided groove was designed based on the principle of the brachistochrone. The overall structure and working principle of the device are described, and the curved segment of the seed guide tube was optimized using the brachistochrone principle while accounting for frictional effects. Computational fluid dynamics (CFD) simulations were conducted to analyse the flow field characteristics of the seed guide tube at inlet airflow velocities of 63.48, 60.64, 57.73, 54.69, 51.50, and 48.15 m/s. A multi-factor test was performed using chamber pressure and operating speed as test factors, with the qualified index of grain spacing and the coefficient of variation as evaluation metrics. Comparative tests were conducted using a traditional guided-groove seed guide tube and a brachistochrone-based seed guide tube without a guided groove. Results showed that the optimal parameter combination for the newly designed device was a chamber pressure of 3.124 kPa and an operating speed of 12.0 km/h. Under these conditions in the bench test, the qualified index reached 97.04%, and the coefficient of variation was 6.18%, outperforming the other two types of seed-guiding devices. These findings demonstrate that the seed-guiding device based on the brachistochrone principle can significantly improve the seeding quality of delta-row planters for dense maize planting under high-speed operation.