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Begomoviruses, viz. squash leaf curl China virus and tomato leaf curl New Delhi virus causative diseases are major concerns of quantitative and qualitative losses in pumpkin ( Cucurbita moschata ) worldwide. Punjab Agricultural University (PAU) in India has identified a resistant source (PVR-1343) against mixed infection (MI-Sq/To) of these begomoviruses. Introgression of resistance in diverse genetic backgrounds requires the identification of quantitative trait loci (QTLs) associated with MI-Sq/To resistance. Phenotyping of 229 F 2:3 progenies derived from the PVR-1343 × P-135 cross revealed digenic recessive inheritance against MI-Sq/To resistance in PVR-1343. To identify the genomic region, resistant and susceptible bulks were subjected to whole-genome resequencing along with their parents. The whole-genome resequence analysis of parents and bulks using QTLseq/QTLseqr approaches identified an overlapping 1.52 Mb region on chromosome 7 ( qMI-Sq/To7.1 ), while chromosomal region spanning 0.87 Mb on chromosome17 ( qMI-Sq/To17.1 ) was additionally identified by QTLseqr. However, the highest peak value on chromosome 7 with three algorithms {G', ∆(SNP-index) and -log 10 ( P value)} highlighted the major contribution of qMI-Sq/To7.1 in MI-Sq/To resistance. Nine polymorphic SNPs identified within the highly significant qMI-Sq/To7.1 region were converted into KASP markers. KASP genotyping of F 2 individuals narrowed down the qMI-Sq/To7.1 interval to 103 kb region flanked by two markers, Cmo3914729 and Cmo4018182, which contained 16 annotated genes and accounted for 59.84% of phenotypic variation. The Cmo4018182 KASP marker accurately predicted disease reaction in 91% of diverse Cucurbita genotypes and showed nonsynonym substitutions in the coding region of putative candidate SYNTAXIN-121 gene. These findings pave the way for marker-assisted breeding and elucidating the underlying mechanism of begomovirus resistance in C. moschata ., Competing Interests: The author(s) declare no conflict of interest.

The hull-less pumpkin ( Cucurbita pepo ) seed does not require de-hulling before use for human consumption, as a result highly preferred by the oil, nut, and baking industries. In hull-less seeds, a single recessive gene is responsible for the absence of outer thick seed coat layers; however, the genomic region and gene(s) controlling the trait are unclear to date. In this study, four crosses attempted to derive F 2 and backcross populations confirmed the single recessive gene inheritance of hull-less seed trait in populations adapted to the sub-tropical climate. The candidate genomic region for hull-less seed trait was identified through the BSA-QTLseq approach using bulks of F 2:3 progenies from a cross of HP111 (hulled) and HLP36 (hull-less). A novel genomic region on chromosome 12 ranging from 1.80 to 3.86 Mb was associated with the hull-less seed trait. The re-sequencing data identified a total of 396 SNPs within this region and eight were successfully converted into polymorphic KASP assays. The genotyping of segregating F 2 ( n = 160) with polymorphic KASP assays resulted in a 40.3 cM partial linkage map and identified Cp_3430407 (10 cM) and Cp_3498687 (16.1 cM) as flanking markers for hull-less locus ( Cphl-1 ). These flanking markers correspond to the 68.28 kb region in the reference genome, and the marker, Cp_3430407 successfully predicted the genotype in 93.33% of the C. pepo hull-less germplasm lines, thus can be used for marker-assisted selection in parents polymorphic for the hull-less seed trait. The Cphl-1 -linked genomic region (2.06 Mb) encompasses a total of 182 genes, including secondary cell wall and lignin biosynthesis-related transcriptional factors viz ., "NAC" ( Cp4.1LG12g04350 ) and "MYB" ( Cp4.1LG12g03120 ). These genes were differentially expressed in the seeds of hulled and hull-less genotypes, and therefore could be the potential candidate genes governing the hull-less seed trait in pumpkin., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kaur, Garcha, Bhatia, Khosa, Sharma, Mittal, Verma and Dhatt.)

A better understanding of how plants adjust their flowering under unfavourable environmental conditions is key to developing climate-resilient crops. Recently, Susila et al. demonstrated that phospholipids controlling the transport of florigen (FLOWERING LOCUS T; FT) act as an additional layer to prevent flowering under unfavourable conditions., (Copyright © 2022 Elsevier Ltd. All rights reserved.)