Biology subjects

Pender, G.

Publications and source records attributed to Pender, G..

3 recordsLinked to original sources

bioRxiv2026

The Viability Gambit: An Optimized Sterilisation Protocol for Industrial Hemp ( Cannabis sativa L.) Seeds

Hemp (Cannabis sativa L.) is an increasingly important crop with applications spanning fibre, seed oil and bioactive cannabinoid production, yet the development of reliable tissue culture systems for this species remains a significant challenge. The establishment of axenic seedling cultures is a prerequisite for hypocotyl-based regeneration and future genetic transformation pipelines, but hemp seeds harbour diverse endophytic microbial communities that frequently overwhelm standard surface sterilisation protocols. Here, we present a systematic comparative evaluation of seed sterilisation strategies across seven industrial hemp accessions, examining the effects of sterilisation chemistry, seed provenance and accession identity on both contamination outcome and the subsequent morphogenic competence of hypocotyl explants. Across all treatments and accessions, in-house glasshouse-harvested seeds achieved higher sterility rates than commercially sourced material regardless of protocol applied. This provenance effect, combined with considerable batch-to-batch variation within seed sources, indicates that contamination load is a primary determinant of successful hemp seed sterilisation. Among the sterilisation treatments evaluated, a baseline of 75% ethanol combined with sequential 1% hydrogen peroxide incubation performed consistently well for low-load seed batches, while supplementation with Plant Preservative Mixture (PPMTM) might be necessary to achieve acceptable rates of non-contaminated seedlings from high contamination load batches. Beyond their effect on contamination, sterilisation treatments influenced the morphogenic fate of hypocotyl explants independently of sterility outcomes. Notably, seedling treatment with the Prochloraz-based fungicide Octave promoted shoot and root co-regeneration in the absence of exogenous plant growth regulators in some cases. Hormone-free organogenesis from hypocotyl explants was achievable across multiple hemp accessions, demonstrating that this developmental capacity is broadly distributed within hemp, though its frequency and consistency varied with accession identity and protocol conditions. Together, these findings provide a practical framework for axenic hemp seed culture that can be used as starting point requiring local adaptation based on seed source, batch history and the intended downstream application.

Plant Biology↗

bioRxiv2026

GENE-FAM: An automated pipeline for mining gene families and its application to MADS-box genes in Cannabis sativa

Understanding how gene families evolve can offer great insight into adaptation at the phenotypic and ecological levels. This is particularly true in plants, where transcription factor gene families are often targeted for breeding programs to improve the agronomic traits of economically important crops. While recent advances in next generation sequencing have accelerated the wealth of genomics data, there remains a lack of accessible and reproducible genome mining pipelines tailored for gene family characterisation. Here, we address this gap by developing GENE-FAM, an automated, scalable and open-source pipeline designed to mine and predict gene families based on conserved domains and motifs. To illustrate its application, we apply GENE-FAM to annotate MADS-box transcription factor genes across multiple Cannabis sativa genomes. A comprehensive set of MADS-box genes was identified across three C. sativa cultivars, including both previously annotated and newly predicted genes. Through phylogenetic analyses, we confirm that all type II MADS-box gene subfamilies represented in flowering plants are present in C. sativa. Comparing our annotations with those of Arabidopsis thaliana and Solanum lycopersicum revealed that while most MADS type II families are highly conserved, SEPALLATA-like genes have undergone diversification in C. sativa. Together, these results demonstrate the application of GENE-FAM for genome-wide identification and characterisation of gene families in non-model species, revealing novel insights into MADS-box gene family evolution in C. sativa.

genomics↗

bioRxiv2023

Exploring phenotypic and genetic variability in hemp (Cannabis sativa)

Hemp (Cannabis sativa L.) is a high-value multi-purpose crop with applications ranging from the medicinal use of its secondary metabolites to carbon-sequestering building materials. To fully capitalise on the potential of hemp as a crop for more sustainable agriculture, detailed phenotypic and genotypic characterizations are required in order to inform targeted breeding programmes. Here, we present a detailed morphological and genomic analysis of 10 hemp cultivars. We found high variability in agronomically important traits such as flowering time, plant height, and biomass in most of the hemp cultivars tested. Additionally, genotyping by sequencing demonstrates that genetic differences are pervasive, both between hemp cultivars as well as between individuals of a single cultivar. The significant genetic and phenotypic variability we observe in hemp contrasts with other crops, where cultivars are often phenotypically and genetically relatively uniform. We argue that the variability of hemp is an asset for breeding and increases the potential for further improvement of the crop but is also a challenge for todays highly automated agriculture that relies on phenotypic uniformity. Author summaryHemp (Cannabis sativa L.) stands as one of the earliest domesticated crops. This remarkable plant is a sustainable crop with high carbon sequestration capacity which can be cultivated for soil remediation. Furthermore, hemp oil and fibre are used for many applications ranging from cooking to manufacturing bioplastics, textiles, or building materials of superb characteristics, and its secondary metabolites are sought after because of their medicinal properties. However, in contrast to many modern crops, hemp exhibits extensive variability in key agricultural traits, such as plant height and flowering time. This variability presents a challenge for both farmers and processors. To unravel the fundamentals of hemp diversity we conducted a comprehensive study of phenotypic and genetic characterisation of ten diverse hemp cultivars. We present findings confirming substantial variability not only among individuals of different cultivars but also within the same cultivar. Additionally, we explore heterozygosity in the context of other hemp studies and other crops. Understanding this variability in the context of a single hemp cultivar and across multiple cultivars is paramount for breeding novel, more uniform hemp varieties which will allow us to unlock the full potential of hemp as a crop of the future.

plant biology↗