Physiological traits, yield, and yield components relationship in winter and spring canola.

BACKGROUND: Understanding the relationship between physiological traits with yield and yield components is an essential step towards developing high-yielding and high-quality canola (Brassica napus L.) cultivars. This study aimed to explore further the relationship between some physiological features, including radiation use efficiency (RUE), and seed yield in canola. RESULTS: Significant differences were found among cultivars regarding maximum leaf area index (LAImax ) and required days to achieve maximum LAI (DLAImax ). All cultivars obtained the minimum LAI required to intercept 90% of the incident radiation, but at different times. Some cultivars like SW102 and Shirali had the same fraction of intercepted photosynthetically active radiation (IPAR) when LAI was maximal, but SW102 had higher IPAR. This indicated that SW102 was more efficient in irradiation capacity and may have a higher photosynthesis rate when exposed to the high irradiation conditions. The average canola RUE in the current study was 3.80 and 3.63 g MJ-1 m-2 in 2014 and 2015, respectively. In general, the crop growth rate was higher in the first year than in the second year due to the fewer cloudy days and more incident radiation. CONCLUSION: Results indicated that duration of growth, crop growth rate, and harvest index were crucial for enhancing biomass and seed yield. Also, a relatively high correlation was found between the RUE and DLAImax . The cultivars that reached their maximum LAI later demonstrated higher RUE, and consequently had higher biological and seed yield. The results obtained could be used to develop an improved canola crop growth model and breeding programs. © 2021 Society of Chemical Industry.

High-density genetic map construction and QTLs identification for plant height in white jute (Corchorus capsularis L.) using specific locus amplified fragment (SLAF) sequencing.

BACKGROUND: Genetic mapping and quantitative trait locus (QTL) detection are powerful methodologies in plant improvement and breeding. White jute (Corchorus capsularis L.) is an important industrial raw material fiber crop because of its elite characteristics. However, construction of a high-density genetic map and identification of QTLs has been limited in white jute due to a lack of sufficient molecular markers. The specific locus amplified fragment sequencing (SLAF-seq) strategy combines locus-specific amplification and high-throughput sequencing to carry out de novo single nuclear polymorphism (SNP) discovery and large-scale genotyping. In this study, SLAF-seq was employed to obtain sufficient markers to construct a high-density genetic map for white jute. Moreover, with the development of abundant markers, genetic dissection of fiber yield traits such as plant height was also possible. Here, we present QTLs associated with plant height that were identified using our newly constructed genetic linkage groups. RESULTS: An F8 population consisting of 100 lines was developed. In total, 69,446 high-quality SLAFs were detected of which 5,074 SLAFs were polymorphic; 913 polymorphic markers were used for the construction of a genetic map. The average coverage for each SLAF marker was 43-fold in the parents, and 9.8-fold in each F8 individual. A linkage map was constructed that contained 913 SLAFs on 11 linkage groups (LGs) covering 1621.4 cM with an average density of 1.61 cM per locus. Among the 11 LGs, LG1 was the largest with 210 markers, a length of 406.34 cM, and an average distance of 1.93 cM between adjacent markers. LG11 was the smallest with only 25 markers, a length of 29.66 cM, and an average distance of 1.19 cM between adjacent markers. 'SNP_only' markers accounted for 85.54% and were the predominant markers on the map. QTL mapping based on the F8 phenotypes detected 11 plant height QTLs including one major effect QTL across two cultivation locations, with each QTL accounting for 4.14-15.63% of the phenotypic variance. CONCLUSIONS: To our knowledge, the linkage map constructed here is the densest one available to date for white jute. This analysis also identified the first QTL in white jute. The results will provide an important platform for gene/QTL mapping, sequence assembly, genome comparisons, and marker-assisted selection breeding for white jute.

Energy, economic, and environmental assessment of coriander seed production using material flow cost accounting and life cycle assessment.

The agricultural sector in the world is facing social expectations to improve energy efficiency and reduce environmental impacts, and at the same producing enough food and fiber for the growing world population. The purpose of the present research is to determine the economic, energy consumption, and environmental impacts in coriander seed production using material flow cost accounting approach along with life cycle assessment. The positive output and negative energy were 25,485 and 6742 MJ ha-1, respectively. Energy efficiency, net energy gain, specific energy, and energy productivity indicators were calculated as 0.6, - 11,944 MJ ha-1, 17.4 MJ kg-1, and 0.06 kg MJ-1, respectively. The average production cost was calculated as 588 $ ha-1 whereas gross income was 1267 $ ha-1. The value of negative products in coriander production was estimated as 239 $ ha-1. Seed shedding at harvest and water loss due to inefficient irrigation system were found to be the major negative products (economic and energy) in the system that can enhance the system productivity upon improvement. The values of benefit costs ratio and economic productivity were 1.74 and 3 kg $-1, respectively. The acidification potential (102.5 kg SO2 eq ha-1), global warming potential (897.3 kg CO2 eq ha-1), photochemical oxidation potential (0.13 kg C2H4 eq ha-1), and eutrophication potential (40.3 kg PO4-3 eq ha-1) indicators were evaluated. The hotspots in point of economic (labor and seed shedding), energy use (nitrogen fertilizer and machinery) and energy loss (seed shedding), and environment (diesel fuel consumption) were determined which can be used to optimize coriander production through decreasing the material and energy consumption in the field. The results showed that MFCA combined with LCA is a powerful tool in identifying hotspots in crop production systems and can be used in developing more sustainable systems as well as in developing sustainability models.