Finger millet (Eleusine coracana (L.) Gaertn) is an important crop for food security because of its tolerance to drought, which is expected to be exacerbated by global climate changes. Nevertheless, it is often classified as an orphan/underutilized crop because of the paucity of scientific attention. Among several small millets, finger millet is considered as an excellent source of essential nutrient elements, such as iron and zinc; hence, it has potential as an alternate coarse cereal. However, high-quality genome sequence data of finger millet are currently not available. One of the major problems encountered in the genome assembly of this species was its polyploidy, which hampers genome assembly compared with a diploid genome. To overcome this problem, we sequenced its genome using diverse technologies with sufficient coverage and assembled it via a novel multiple hybrid assembly workflow that combines next-generation with single-molecule sequencing, followed by whole-genome optical mapping using the Bionano Irys® system. The total number of scaffolds was 1,897 with an N50 length >2.6 Mb and detection of 96% of the universal single-copy orthologs. The majority of the homeologs were assembled separately. This indicates that the proposed workflow is applicable to the assembly of other allotetraploid genomes.

Factors associated with variation in harvest index and approaches to improve harvest index (HI) and productivity in sunflower are discussed in this article. In recent years, higher productivity in sunflower has been achieved mainly through increased crop growth rates. Besides, an improvement in harvest index also has contributed for improved productivity to a certain extent. In our study we observed that medium duration types (100 to 110 days) had high HI compared with early or long-duration varieties and we also attempted to understand the ways and means to improve HI in sunflower types with varied duration. Genotypes which had low partitioning of dry matter to stem plus thalamus had high HI. Genotypes which accumulated high biomass during post flowering stages of development also showed high HI and seed yield. In a few genotypes remobilization of photosynthates from vegetative plant parts to the seed resulted in high HI and seed yield. Among the sink characters, the number of seed per head, test weight and seed density (weight/volume) also contributed to achieving high HI values. Identification and selection of genotypes based on these criteria will increase the production further. Since large amount of biomass is still locked up in the vegetative plant parts, any practice to manipulate the mobilization of photosynthates from vegetative parts to head also improves HI and thus seed yield. In our experiment, we observed that foliar application of boron nutrient and application of growth regulators to the head improved the translocation of photosynthates to the head and thus increased the HI and seed yield.

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