Early Plant Research Articles

Supply of phosphorus and nitrogen affects both growth and development rates in onion

ABSTRACT The hypothesis that soil anion storage capacity (ASC) directly influences the response of onion yield to soil Olsen P status was tested. Onions were grown to maturity in three different soils in the same tunnel house. Each soil received three rates of phosphorus (P) fertiliser 1 month before planting, and at planting soil ASC and Olsen P status was measured. Although bulb yield increased with Olsen P (over the range 15–95 μg g−1), ASC (which varied from 10 to 70%) had no influence on this response. This supports recent findings with young onions grown in small pots, but contradicts previous advice to vegetable growers. The results show that low to moderate soil Olsen P values and low initial availability of N, slow early plant growth and development. Delays in maturity due low P input may allow growth to catch up, at least partially, later in the season. This has implications for the design and execution of field experiments to test P fertilisers for onions and suggests that visible responses to P fertiliser in young onion crops may be misleading.

Effects of Conservation Tillage Method, Phosphorus Level, and Variety on Soil Organic Carbon and Cowpea Performance at Minna in Nigeria’s Southern Guinea Savanna

The study was carried out at the Teaching and Research Farm of the Federal University of Technology Minna, Gidan Kwano Campus in Latitude 9° 41' N, Longitude 6° 31' E, and Altitude 258.5 m above sea level. This study was conducted across 2 seasons within the cropping season of 2017 to determine the effects of tillage method, phosphorus level, and cowpea variety on soil organic carbon and cowpea performance in Minna. The experiment was therefore a 3x3x3 factorial arrangement in a split-plot design with tillage methods (zero, reduced, and manual ridging) and cowpea varieties (IT93K-452-1, IT99K-573-1-1, and IT90K-277-2) forming the main plot while phosphorus levels (0 P kg ha-1, 30 P kg ha-1, and 60 P kg ha-1) formed the sub-plot with 3 replicates. Results obtained revealed that soil organic carbon was not significantly affected by tillage method and phosphorus level alone, regardless of the planting season. Cowpea variety alone significantly affected organic carbon only in the late planting season. Zero tillage, 60 kg P ha-1, and IT93K-452-1 produced the highest soil organic carbon content, respectively. In the early season, N fixed was highest (0.98 g plant-1) when cowpea was fertilized with 60 Kg P ha-1 under zero tillage. The closest to this value (0.92 g plant-1) was recorded in the late season when 60 kg P ha-1 was supplied to cowpea under manual tillage. Regardless of the planting season and varietal difference, cowpea recorded the highest N fixed when fertilized with 60 kg P ha-1. Across varieties, cowpea fixed more N under zero tillage than the other tillage methods, especially in the early season. In the late season, only IT90K-277-2 fixed N (0.49 g plant-1) under zero tillage that was statistically not different from the highest N fixed due to manual tillage of soil under the cultivation of IT93K-452-1 and IT99K-573-1-1 (0.62 g plant-1, respectively). In the early season, IT99K-573-1-1 cultivated under zero tillage produced the highest grain yield (404.11 kg ha-1). Fodder yield followed a different trend compared to grain yield. In the early planting season, cowpea fertilized with 60 kg P ha-1 produced the highest fodder yield, while in the late season, the application of 30 kg P ha-1 produced the highest fodder yield. Regardless of the planting season, grain yield was highest when IT99K-573-1-1 was fertilized with 60 kg P ha-1. Averagely, soil organic carbon content, N fixed, and grain yield values were highest during the late planting than the early planting season. The reverse was, however, the case for fodder yield, seedling emergence, root length, root, and shoot biomass, respectively. For the best performance in cowpea production, farmers are encouraged to plant IT99K-573-1-1 on zero-tilled soil with phosphorus application at the rate of 60 kg ha-1. IT90K-277-2, which is the most genetically stable variety across seasons, will be most ideal in controlling negative climate change and should therefore be considered for further investigations.

Coupling field monitoring with crop growth modelling provides detailed insights on yield gaps at field level: A case study on ware potato production in the Netherlands

ContextYield gap analyses are useful to assess and benchmark the productivity of cropping systems. Often such analyses are performed at higher aggregation levels. As a result, these studies lack the detail to explain yield gaps at field level and hence make it difficult to translate findings into precise recommendations to farmers and extensionists. ObjectiveThis study provides a detailed approach for yield gap assessments at field level through coupling frequent field monitoring in farmers’ fields with crop growth modelling. We used ware potato production in the Netherlands as a case to study yield gaps at field level, as average productivity is high whilst yields are still highly variable among fields, and as ware potato is an important cash crop for farmers. MethodsOver two growing seasons, 96 ware potato fields were monitored throughout the growing season on a biweekly basis, taking measurements on soil, crop growth and yield. The crop growth model SWAP-WOFOST was used to simulate potential and water-limited potential yields. Various statistical methods were used to quantify yield gap explaining factors. ResultsThe average yield gap ranged from 20 to 31% depending on the year and soil type. Among fields, the yield gap ranged from 0 to 51%. On clayey soils, the yield gap was attributed mostly to oxygen stress. On sandy soils, the yield gap was determined mostly by drought stress in 2020, a relatively dry year, and by reducing factors (pests, diseases and poor agronomic practices) in 2021, an average year in terms of precipitation. The type of reducing factors differed per field. Furthermore, we found that earlier planting and later harvesting can increase yields, as Yp is radiation-limited. ConclusionsOverall, there is limited scope to narrow the yield gap as current ware potato production is already close to 80% of the potential yield, which is assumed to be approximately the maximum farmers can attain. However, yield and resource use efficiency gains are to be made for individual fields. Furthermore, we conclude that frequent field monitoring coupled with crop growth modelling is a powerful way to assess yield gap variability and to get detailed insight in the yield gap explaining factors at field level. SignificanceThis study showed that coupling frequent field monitoring with crop growth modelling allows to gain detailed insight in yield gap variability among fields. This method provides detailed information about yield gap explaining factors which can be used to improve yield and resource use efficiency at field level.

Constraints militating against the use of adaptation strategies to climate change effects by small-scale rice farmers in Northeastern, Nigeria

This study ascertained the constraints militating against the use of adaptation strategies to climate change effects amongst rice farmers in Northeastern Nigeria. Multi-stage sampling technique was used to select 300 rice farmers. The analytical tools used to analyze the data obtained were descriptive and inferential statistics. The result shows the used and unused adaptation strategies for drought resistant rice variety were 33.0% and 67.0%, heat resistant rice variety were 30.7% and 69.3%, short rice cycle seeds were 2.3% and 97.7%, early maturing rice variety were 32.7% and 67.3%, early planting were 32.0% and 68.0%, late planting were 33.0% and 67.0%, early harvesting were 32.7% and 67.3%, late harvesting were 31.7% and 68.3. The result on constraints militating against the use of adaptation strategies shows that the constraints with higher loading factors were low level of income (λ=0.799), low literacy level (λ=0.727), inadequate knowledge on how to cope with climate change related issues (λ=0.761), poor response to climate related issues (λ=0.782), poor financial support from NGOs (0.648), inadequate agricultural loans (0.655) and high administrative charges on loan (λ=0.555). Other constraints included inadequate extension workers (λ=0.583), inadequate extension contacts (λ=0.550), long bureaucracy in getting formal credit (λ=0.588), lack of reliable sources of information on climate change (λ=0.708), loans not readily available during farming season (λ=0.752), and inadequate financial support from government (0.428). Based on the findings of the study, it is concluded that low users of adaptation strategies were evident in the zone. Therefore, it is recommended that the government should encourage the use of adaptation strategies in the zone.

Endomembrane-biased dimerization of ABCG16 and ABCG25 transporters determines their substrate selectivity in ABA-regulated plant growth and stress responses

ATP-binding cassette (ABC) transporters are integral membrane proteins that have evolved diverse functions fulfilled via the transport of various substrates. In Arabidopsis, the G subfamily of ABC proteins is particularly abundant and participates in multiple signaling pathways during plant development and stress responses. In this study, we revealed that two Arabidopsis ABCG transporters, ABCG16 and ABCG25, engage in ABA-mediated stress responses and early plant growth through endomembrane-specific dimerization-coupled transport of ABA and ABA-glucosyl ester (ABA-GE), respectively. We first revealed that ABCG16 contributes to osmotic stress tolerance via ABA signaling. More specifically, ABCG16 induces cellular ABA efflux in both yeast and plant cells. Using FRET analysis, we showed that ABCG16 forms obligatory homodimers for ABA export activity and that the plasma membrane-resident ABCG16 homodimers specifically respond to ABA, undergoing notable conformational changes. Furthermore, we demonstrated that ABCG16 heterodimerizes with ABCG25 at the endoplasmic reticulum (ER) membrane and facilitates the ER entry of ABA-GE in both Arabidopsis and tobacco cells. The specific responsiveness of the ABCG16-ABCG25 heterodimer to ABA-GE and the superior growth of their double mutant support an inhibitory role of these two ABCGs in early seedling establishment via regulation of ABA-GE translocation across the ER membrane. Our endomembrane-specific analysis of the FRET signals derived from the homo- or heterodimerized ABCG complexes allowed us to link endomembrane-biased dimerization to the translocation of distinct substrates by ABCG transporters, providing a prototypic framework for understanding the omnipotence of ABCG transporters in plant development and stress responses.

Distinctive Aspects of Early Open-Field Watermelon Production

This study emphasizes the economic significance of watermelon cultivation in the Republic of Serbia, introducing innovative techniques such as seedling production, grafting, mulching with black polyethylene film and low tunnels. Collectively, these methods contribute to earlier planting, improved crop development, and enhanced fruit quality. Grafting, particularly using Lagenaria siceraria and Cucurbita species, positively impacts yields and flowering. The incorporation of black polyethylene film aids in weed control, reduces herbicide usage, and minimizes labor inputs. Low tunnels, with transparent film covers, modify microclimates, allowing for earlier harvests. These integrated practices offer a sustainable approach to advancing watermelon cultivation techniques, potentially influencing agricultural practices on a global scale by promoting efficiency, yield optimization, and resource conservation.

MiRNAs differentially expressed in vegetative and reproductive organs of Marchantia polymorpha – insights into their expression pattern, gene structures and function

ABSTRACT MicroRNAs regulate gene expression affecting a variety of plant developmental processes. The evolutionary position of Marchantia polymorpha makes it a significant model to understand miRNA-mediated gene regulatory pathways in plants. Previous studies focused on conserved miRNA-target mRNA modules showed their critical role in Marchantia development. Here, we demonstrate that the differential expression of conserved miRNAs among land plants and their targets in selected organs of Marchantia additionally underlines their role in regulating fundamental developmental processes. The main aim of this study was to characterize selected liverwort-specific miRNAs, as there is a limited knowledge on their biogenesis, accumulation, targets, and function in Marchantia. We demonstrate their differential accumulation in vegetative and generative organs. We reveal that all liverwort-specific miRNAs examined are encoded by independent transcriptional units. MpmiR11737a, MpmiR11887 and MpmiR11796, annotated as being encoded within protein-encoding genes, have their own independent transcription start sites. The analysis of selected liverwort-specific miRNAs and their pri-miRNAs often reveal correlation in their levels, suggesting transcriptional regulation. However, MpmiR11796 shows a reverse correlation to its pri-miRNA level, suggesting post-transcriptional regulation. Moreover, we identify novel targets for selected liverwort-specific miRNAs and demonstrate an inverse correlation between their expression and miRNA accumulation. In the case of one miRNA precursor, we provide evidence that it encodes two functional miRNAs with two independent targets. Overall, our research sheds light on liverwort-specific miRNA gene structure, provides new data on their biogenesis and expression regulation. Furthermore, identifying their targets, we hypothesize the potential role of these miRNAs in early land plant development and functioning.

Heat Treatments at Varying Ambient Temperatures and Durations Differentially Affect Plant Defense to Blumeria hordei in a Resistant and a Susceptible Hordeum vulgare Line.

Our previous research showed that a powdery mildew resistant barley line (MvHV07-17) maintains its resistance to Blumeria hordei (Bh) even if plants are exposed to a long-term high temperature of 35°C for 120 h before Bh inoculation, whereas such high temperature pretreatment further increases susceptibility to infection in the susceptible barley line MvHV118-17. In the present study, we extended this approach using short-term high-temperature water treatment (49°C for 30 s) to determine how it affects powdery mildew resistance in these barley lines. We found that this short-term heat shock (HS) impaired plant defense responses, as reflected by development of Bh colonies and visible necrotic spots on leaves of MvHV07-17, which does not develop visible symptoms upon Bh inoculation under optimal growth conditions. In contrast, both HS and long-term heat stress enhanced susceptibility to Bh in MvHV118-17 plants. These results were supported by the measurement of Bh biomass using a qPCR method. Furthermore, microscopic examinations showed that HS elevated the rate of successful Bh penetration events and the spread of cell death in the surrounding mesophyll area and allowed for colony formation and sporulation in resistant barley, whereas early and effective plant defense responses, such as papilla formation and single-cell epidermal hypersensitive response, were significantly reduced. Furthermore, we found that the accumulation of hydrogen peroxide in both resistant and susceptible barley was correlated with susceptibility induced by HS and long-term heat-stress. This study may contribute to a better understanding of plant defense responses to Bh in barley exposed to heat. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Conserved CKI1-mediated signaling is required for female germline specification in Marchantia polymorpha

In land plants, gametes derive from a small number of dedicated haploid cells.1 In angiosperms, one central cell and one egg cell are differentiated in the embryo sac as female gametes for double fertilization, while in non-flowering plants, only one egg cell is generated in the female sexual organ, called the archegonium.2,3 The central cell specification of Arabidopsis thaliana is controlled by the histidine kinase CYTOKININ-INDEPENDENT 1 (CKI1), which is a two-component signaling (TCS) activator sharing downstream regulatory components with the cytokinin signaling pathway.4,5,6,7 Our phylogenetic analysis suggested that CKI1 orthologs broadly exist in land plants. However, the role of CKI1 in non-flowering plants remains unclear. Here, we found that the sole CKI1 ortholog in the liverwort Marchantia polymorpha, MpCKI1, which functions through conserved downstream TCS components, regulates the female germline specification for egg cell development in the archegonium. In M.polymorpha, the archegonium develops three-dimensionally from a single cell accumulating MpBONOBO (MpBNB), a master regulator for germline initiation and differentiation.8 We visualized female germline specification by capturing the distribution pattern of MpBNB in discrete stages of early archegonium development, and found that MpBNB accumulation is restricted to female germline cells. MpCKI1 is required for the proper MpBNB accumulation in the female germline, and is critical for the asymmetric cell divisions that specify the female germline cells. These results suggest that CKI1-mediated TCS originated during early land plant evolution and participates in female germ cell specification in deeply diverged plant lineages.

A subclass II bHLH transcription factor in Marchantia polymorpha gives insight into the ancestral land plant trait of spore formation

Sporopollenin is often said to be one of the toughest biopolymers known to man. The shift in dormancy cell wall deposition from around the diploid zygotes of charophycean algae to sporopollenin around the haploid spores of land plants essentially imparted onto land plants the gift of passive motility, a key acquisition that contributed to their vast and successful colonization across terrestrial habitats.1,2 A putative transcription factor controlling the land plant mode of sporopollenin deposition is the subclass II bHLHs, which are conserved and novel to land plants, with mutants of genes in angiosperms and mosses divulging roles relating to tapetum degeneration and spore development.3,4,5,6,7 We demonstrate that a subclass II bHLH gene, MpbHLH37, regulates sporopollenin biosynthesis and deposition in the model liverwort Marchantia polymorpha. Mpbhlh37 sporophytes show a striking loss of secondary wall deposits of the capsule wall, the elaters, and the spore exine, all while maintaining spore viability, identifying MpbHLH37 as a master regulator of secondary wall deposits of the sporophyte. Localization of MpbHLH37 to the capsule wall and elaters of the sporophyte directly designates these tissue types as a bona fide tapetum in liverworts, giving support to the notion that the presence of a tapetum is an ancestral land plant trait. Finally, as early land plant spore walls exhibit evidence of tapetal deposition,8,9,10,11,12 a tapetal capsule wall could have provided these plants with a developmental mechanism for sporopollenin deposition.

Influence of different population densities of Bambara groundnut intercrop and weeding frequency on maize (<i>Zea mays</i> L.) performance

Effective weed management is essential for enhanced productivity of maize. A two-year field experiment was carried out at the Department of Crop Science Demonstration Farm, University of Calabar, Calabar, Nigeria (4.5-5.20 N, 8.0-8.30 E), in the 2019 and 2020 early planting seasons, to evaluate the influence of three population densities of Bambara groundnut [166,666 plants per hectare(B1), 100,000 plants per hectare (B2), 71,428 plants per hectare (B3)] and four hand weeding frequencies [weedy check (WC), one hand weeding (1HW), two hand weedings (2HW) and a weed free check (WFC)] on the performance of maize. The experiment consisted of three replications fitted into a Randomized Complete Block Design (RCBD). Data gathered on maize vegetative and yield characteristics were analysed using analysis of variance (ANOVA) procedures for RCBD (GenStat® statistical package, version 8.1). Significantly different means were compared at 5 % probability level using the Duncan’s New Multiple Range Test (DNMRT). From the results, maize growth and yield performance were significantly (P<0.05) affected by Bambara groundnut populations and the frequency of weeding. Leaving weeds unchecked all through the cultivation season hampered the vegetative and yield performance of maize, resulting in 47.54 % reduction in maize grain yield, compared with the weeded plots. Conclusively, intercropping maize with Bambara groundnut at 71,428 plants per hectare integrated with two hand weedings at 4 and 8 weeks after sowing (WAS), which optimized maize grain yield (3.87 t/ha on the two-year average) is recommended for farmers in the Calabar humid area and its environs.

Revealing the transitory and local effect of zebularine on development and on proteome dynamics of Salix purpurea.

DNA methylation plays major roles in the epigenetic regulation of gene expression, transposon and transcriptional silencing, and DNA repair, with implications in developmental processes and phenotypic plasticity. Relevantly for woody species, DNA methylation constitutes a regulative layer in cell wall dynamics associated with xylogenesis. The use of methyltransferase and/or demethylase inhibitors has been proven informative to shed light on the methylome dynamics behind the regulation of these processes. The present work employs the cytidine analog zebularine to inhibit DNA methyltransferases and induce DNA hypomethylation in Salix purpurea plantlets grown in vitro and in soil. An integrative approach was adopted to highlight the effects of zebularine on proteomic dynamics, revealing age-specific (3 weeks of in vitro culture and 1 month of growth in soil) and tissue-specific (stem and root) effects. After 3 weeks of recovery from zebularine treatment, a decrease of 5-mC levels was observed in different genomic contexts in the roots of explants that were exposed to zebularine, whereas a functionally heterogeneous subset of protein entries was differentially accumulated in stem samples, including entries related to cell wall biosynthesis, tissue morphogenesis, and hormonal regulation. Significant proteomic remodeling was revealed in the development from in vitro to in-soil culture, but no significant changes in 5-mC levels were observed. The identification of tissue-specific proteomic hallmarks in combination with hypomethylating agents provides new insights into the role of DNA methylation and proteome in early plant development in willow species. Proteomic data are available via ProteomeXchange with identifier PXD045653. WGBS data are available under BioProject accession PRJNA889596.

The role of zinc fertilization and its interaction with nitrogen and phosphorus starter fertilization on early maize development and grain yield

The early planting of maize in temperate growing areas leads to yield and quality benefits, although a low soil temperature can affect the early nutrient uptake and delay plant development. Not only can the nitrogen (N) and phosphorus (P) uptake be limited, but that of zinc (Zn) can also be affected. Moreover, the application of N and P at early growth stages can result in an enhancement of maize growth. Two field experiment were carried out in North Italy during the 2012–14 period to: i) evaluate the most effective Zn application strategy by comparing seed, soil and foliar applications with an untreated control; ii) investigate the role of a Zn seed treatment on the early development and yield of maize grown in three different types of soils. The effect of Zn application was compared, in both experiments, to starter NP fertilization in bands at planting, according to a full factorial design. Zn fertilization significantly enhanced the early vigor and yield of the maize, although the effects were less pronounced than those of the NP fertilizer. Among the Zn fertilization strategies, maize growth was quicker for the seed and soil applications than for the foliar application or the untreated control. The former application significantly increased the plant height at stem elongation (+32%), shortened the planting-flowering period by 1 day, and increased the grain yield by 4%. Overall, the application of NP starter fertilizer shortened the planting-flowering period by 4.5 days and increased the yield by 10%, compared to the unfertilized control. In the second experiment, higher plant vigor indices were detected in all the soils for the NP starter fertilization (+22–27%) and for the Zn seed treatment (+3–9%) than in the controls. The NP starter fertilization reduced the grain moisture at harvest by 2.3% and increased grain yield by 14%, while the Zn treatment significantly increased the kernel weight but did not affect the grain yield or the moisture content. The interaction between the NP fertilization and the Zn treatment was never significant. Thus, the positive effect of Zn on the early vigor was an additional benefit to that produced by the starter NP fertilization. The study demonstrated that a Zn application at planting, with both a seed dressing and a soil treatment, significantly enhanced the early growth of different maize hybrids, in different growing seasons and soils, although the use of a NP starter fertilization led to more consistent agronomic benefits. Furthermore, the combination of NP and Zn starter fertilization resulted in a further advantage for all the considered production situations.

Mycorrhizal association and its relation with pteridophytes.

Mycorrhizal association is one of the earliest and diversely distributed symbiotic associations on the Earth. This association helped early terrestrial plants to colonize the land by improved supply of nutrients like phosphate, nitrogen and zinc. It also helped plants to tolerate unfavorable soil conditions with increased water retention capacity, resistance to drought and pathogens. In return, fungi benefitted with carbon as their food source from the plants. More than 80% of terrestrial plants including pteridophytes, gymnosperms and angiosperms are reported to form arbuscular mycorrhizal (AM) association. Plants with root systems appeared on land during the Devonian period and many of them like pteridophytes still exist today. Various molecular and fossil studies confirm that the plants belonging to Ordovician-Devonian are associated with fungi, which are very similar to genus Glomus. AM association is very common in pteridophytes and the growth of its sporophyte and gametophyte is directly affected in the presence of AM association. Pteridophytes as early land plants with root systems have a very significant place in the plant kingdom. They have evolved and adapted to fill various habitats and facilitated early terrestrialization of other land plants by providing suitable niche with the help of AM fungi. In spite of pteridophytes being a very important plant group in the land system, very few reports are available on fungal-pteridophyte association. The present review is an effort to gather information about AM association in pteridophytes that might help in unraveling the evolution and significance of plant and fungi association.

Retreating coastal forest supports saltmarsh invertebrates

AbstractAs sea‐level rise converts coastal forest to salt marsh, marsh arthropods may migrate inland; however, the resulting changes in arthropod communities, including the stage of forest retreat that first supports saltmarsh species, remain unknown. Furthermore, the ghost forest that forms in the wake of rapid forest retreat offers an unknown quality of habitat to marsh arthropods. In a migrating marsh in Virginia, USA, ground‐dwelling arthropod communities were assessed across the forest‐to‐marsh gradient, and functional use of ghost forest and high marsh habitats was evaluated to determine whether marsh arthropods utilized expanded marsh in the same way as existing marsh. Diet and body condition were compared for two marsh species found in both high marsh and ghost forest (the detritivore amphipod, Orchestia grillus, and the hunting spider, Pardosa littoralis). Community composition differed among zones along the gradient, driven largely by retreating forest taxa (e.g., Collembola), marsh taxa migrating into the forest (e.g., O. grillus), and unique taxa (e.g., Hydrophilinae beetles) at the ecotone. The low forest was the most inland zone to accommodate the saltmarsh species O. grillus, suggesting that inland migration of certain saltmarsh arthropods may co‐occur with early saltmarsh plant migration and precede complete tree canopy die‐off. Functionally, O. grillus occupied a larger trophic niche in the ghost forest than the high marsh, likely by consuming both marsh and terrestrial material. Despite this, both observed marsh species primarily consumed from the marsh grass food web in both habitats, and no lasting differences in body condition were observed. For the species and functional traits assessed, the ghost forest and high marsh did not show major differences at this site. Forest retreat and marsh migration may thus provide an important opportunity for generalist saltmarsh arthropods to maintain their habitat extent in the face of marsh loss due to sea‐level rise.

Transcriptome-based analysis of candidate gene markers associated with resistance mechanism to Phytophthora melonis that causes root and crown rot in pumpkin.

Root and crown rot incited by an oomycete, Phytophthora melonis, causes significant yield losses in commercial pumpkin (Cucurbita pepo) production worldwide. Currently, resistant cultivars and knowledge of molecular mechanism of C. pepo against P. melonis are scarce. Here, we analysed the quantitative gene expression changes of 10 candidate gene markers (bHLH87, ERF014, HSF, MYB, PR-1, WRKY21, CPI, POD, PSK, SGT) in pumpkin roots and leaves at three time points (h post-inoculation, hpi) following inoculation with P. melonis in two resistant (Ghelyani and Tanbal), and two susceptible (Marmari and Khoreshti) varieties of pumpkin. Gene expression using quantitative real time PCR along a time course revealed the strongest transcriptomic response at 48 and 72hpi in resistant genotypes, 1.1-2.7-fold in roots and leaves, respectively, with a high significant correlation (r=0.857**-0.974**). We also found that CPI, PSK, SGT1 and POD act as a dual regulator that similarly modulate immunity not only against P. melonis, but also against other diseases such as early blight (Alternaria cucumerina), powdery mildew (Podosphaera xanthii), downy mildews (Pseudoperonospora cubensis), and pathogenic plant nematodes (Meloidogyne javanica). Furthermore, significantly higher activities of the ROS scavenging defence enzymes, catalase (1.6-fold increase) and peroxidase (6-fold increase) were observed in the roots of resistant cultivars at different hpi compared with non-inoculated controls. In addition, the biomass growth parameters including leaf and root length, stem and root diameter, root fresh weight and volume were significantly different among studied genotypes. Cumulatively, the transcriptome data provide novel insights into the response of pumpkins for improving pumpkin breeding to P. melonis.

Longitudinal genome-wide association study reveals early QTL that predict biomass accumulation under cold stress in sorghum.

Sorghum bicolor is a promising cellulosic feedstock crop for bioenergy due to its high biomass yields. However, early growth phases of sorghum are sensitive to cold stress, limiting its planting in temperate environments. Cold adaptability is crucial for cultivating bioenergy and grain sorghum at higher latitudes and elevations, or for extending the growing season. Identifying genes and alleles that enhance biomass accumulation under early cold stress can lead to improved sorghum varieties through breeding or genetic engineering. We conducted image-based phenotyping on 369 accessions from the sorghum Bioenergy Association Panel (BAP) in a controlled environment with early cold treatment. The BAP includes diverse accessions with dense genotyping and varied racial, geographical, and phenotypic backgrounds. Daily, non-destructive imaging allowed temporal analysis of growth-related traits and water use efficiency (WUE). A genome-wide association study (GWAS) was performed to identify genomic intervals and genes associated with cold stress response. The GWAS identified transient quantitative trait loci (QTL) strongly associated with growth-related traits, enabling an exploration of the genetic basis of cold stress response at different developmental stages. This analysis of daily growth traits, rather than endpoint traits, revealed early transient QTL predictive of final phenotypes. The study identified both known and novel candidate genes associated with growth-related traits and temporal responses to cold stress. The identified QTL and candidate genes contribute to understanding the genetic mechanisms underlying sorghum's response to cold stress. These findings can inform breeding and genetic engineering strategies to develop sorghum varieties with improved biomass yields and resilience to cold, facilitating earlier planting, extended growing seasons, and cultivation at higher latitudes and elevations.

Presowing Mechanical Seed Treatment Influencing the Emergence and Primary Seedling Vigor of Jujube (Ziziphus mauritiana Lam.)

Rootstock preparation from seed is the prerequisite for fruit crop multiplication through grafting or budding, and hard seed coat in jujube has been the proven question for uniform seed germination and subsequent seedling growth. Therefore, the study aimed at successful and rapid production of uniform and healthy jujube rootstocks through applying mechanical seed priming at the presowing stage. The experiment was set in a randomized complete block design where scrapped seeds, cracked seeds, seed kernels, and intact seeds (control) were sown in polybags keeping five replications. The emergence and initial seedling growth were evaluated to sort out the best pretreatment methods for successful stock seedling production in jujube. Seed cracking resulted in the highest germination (69.00%) compared to other pretreatments and also showed better performance in respect of earliness of emergence (10.40 days (d) for the first emergence and 20.40 d for final emergence). Regarding the early plant vigor, significantly maximum seedling height (23.73 cm) and fresh (3.91 g) and dry weight (1.17 g) of seedling and the second‐best leaf number (14.24 seedling−1) were also noted in seed cracking. Although seed kernel had the fastest emergence in 7.20 d, and statistically similar seedling vigor with that of cracked seed but it possessed very low germination percentage (27.00%) compared to the best treatment. Meanwhile, seed priming by scrapping exhibited statistically inferior germination rate (32%) as of intact seed (21%), and below par seedling growth compared to cracked seed. So, seed pretreatment by cracking can be suggested for commercial stock plant regeneration in hard seed‐coated plant species.

Biostimulants in agriculture: innovations in seed treatment and coating technologies

Biostimulants have emerged as a promising tool in modern agriculture to enhance crop productivity and resilience. This review provides a comprehensive overview of the current state of knowledge on the use of biostimulants in seed treatment and coating technologies. The physiological and biochemical mechanisms of action of various biostimulants, including seaweed extracts, humic substances, protein hydrolysates and microbial inoculants, on seed germination and early plant growth are discussed. Different methods of applying biostimulants to seeds, including priming and soaking, are examined, highlighting their advantages and limitations. The review also explores the effects of biostimulant seed treatments on plant growth, development under optimal conditions and stress tolerance under suboptimal conditions. Future perspectives and recommendations for the development and use of biostimulant seed treatments in agriculture are provided, emphasising the need for standardised testing protocols, context-specific approaches, and integration with other sustainable practices.

A Stochastic Frontier Analysis of Maize Production Efficiency and Its Climate-Smart Agricultural Practice Determinants in Southeast, Nigeria

Efficient maize production and resource allocation are crucial for agricultural sustainability, particularly in climate-vulnerable areas like Southeast Nigeria. This study employs stochastic frontier analysis (SFA) to investigate the efficiency of maize production and the determinants of allocative efficiency under climate-smart agricultural practices (CSAPs). The study includes 375 maize farmers selected randomly for the research sample. The analysis begins with estimating the efficiency parameter of maize production, revealing a relatively low Sigma-square value (0.029) and a moderate Gamma value (0.786). The study found a positive association between various inputs such as landholding, seed quality, and organic manure application. The mean TE and AE are 0.894 and 0.747 respectively. Allocative efficiency analysis reveals that while water management practices significantly affect technical efficiency positively, they unexpectedly lead to lower AE. Access to information and adoption of early planting positively influence allocative efficiency. Further examination of socioeconomic determinants indicates the role of extension services (3.07)*** in enhancing AE, while cooperative membership negatively impacts it, possibly due to information asymmetry. These findings emphasize the need for tailored interventions to optimize resource allocation strategies and enhance agricultural productivity and sustainability in Southeast Nigeria, particularly amidst the challenges posed by climate change. Comprehending the complex dynamics of resource allocation and efficiency in agriculture is crucial for crafting efficient policies and interventions aimed at improving productivity and resilience amidst changing climate conditions.