Genome-Wide Association Study Identifies the Serine/Threonine Kinase ClSIK1 for Low Nitrogen Tolerance in Watermelon Species.

Plants have evolved multiple complex mechanisms enabling them to adapt to low nitrogen (LN) stress via increased nitrogen use efficiency (NUE) as nitrogen deficiency in soil is a major factor limiting plant growth and development. However, the adaptive process and evolutionary roles of LN tolerance-related genes in plants remain largely unknown. In this study, we resequenced 191 watermelon accessions and examined their phenotypic differences related to LN tolerance.

Promoter variations of ClERF1 gene determines flesh firmness in watermelon.

Background: Flesh firmness is a critical factor that influences fruit storability, shelf-life and consumer's preference as well. However, less is known about the key genetic factors that are associated with flesh firmness in fresh fruits like watermelon.

Results: In this study, through bulk segregant analysis (BSA-seq), we identified a quantitative trait locus (QTL) that influenced variations in flesh firmness among recombinant inbred lines (RIL) developed from cross between the Citrullus mucosospermus accession ZJU152 with hard-flesh and Citrullus lanatus accession ZJU163 with soft-flesh.

A large presence/absence variation in the promotor of the ClLOG gene determines trichome elongation in watermelon.

The ClLOG gene encoding a cytokinin riboside 5'-monophosphate phosphoribohydrolase determines trichome length in watermelon, which is associated with its promoter variations. Trichomes, which are differentiated from epidermal cells, are special accessory structures that cover the above-ground organs of plants and possibly contribute to biotic and abiotic stress resistance. Here, a bulked segregant analysis (BSA) of an F population with significant variations in trichome length was undertaken.

Allelic variations of ClACO gene improve nitrogen uptake via ethylene-mediated root architecture in watermelon.

The ClACO gene encoding 1-aminocyclopropane-1-carboxylate oxidase enabled highly efficient N uptake in watermelon. Nitrogen is one of the most essential nutrient elements that play a pivotal role in regulating plant growth and development for crop productivity. Elucidating the genetic basis of high nitrogen uptake is the key to improve nitrogen use efficiency for sustainable agricultural productivity.

Pan-genome analysis sheds light on structural variation-based dissection of agronomic traits in melon crops.

Sweetness and appearance of fresh fruits are key palatable and preference attributes for consumers and are often controlled by multiple genes. However, fine-mapping the key loci or genes of interest by single genome-based genetic analysis is challenging. Herein, we present the chromosome-level genome assembly of 1 landrace melon accession (Cucumis melo ssp.

Structural variation of GL1 gene determines the trichome formation in Brassica juncea.

A 448 kb region on chromosome B02 was delimited to be associated with trichome trait in Brassica juncea, in which the BjuVB02G54610 gene with a structural variation of 3 kb structure variation (SV) encoding a MYB transcription factor was predicted as the possible candidate gene. Mustards (Brassica juncea) are allopolyploid crops in the worldwide, and trichomes are essential quality attributes that significantly influence its taste and palpability in vegetable-use cultivars. As important accessory tissues from specialized epidermal cells, trichomes also play an important role in mitigating biotic and abiotic stresses.