Horticultural Research Institute

Delivery of biomolecules into plant vascular tissues remains a barrier to managing diseases caused by insect vector-borne pathogens and to modifying phenotypes of established perennial crops. Inspired by the vascularized growth of crown galls induced by Agrobacterium tumefaciens, we repurposed the bacterium’s plant growth regulator (PGR) genes to engineer autonomously dividing, transgene-expressing plant cell structures termed symbionts. A plant transformation vector (pSYM) incorporating the IaaM, IaaH, Ipt and gene5 cassette from A. tumefaciens strain C58 together with a gene of interest on the same transfer DNA was delivered to stems of herbaceous and woody dicots using disarmed A. tumefaciens strain EHA105. Symbiont morphology, vascular differentiation, transgene expression, molecular mobility and protein secretion were evaluated using microscopy, fluorescent reporters, dye tracing, RNA silencing assays and mass spectrometry-based proteomics. pSym inoculation reproducibly generated symbionts across diverse host plant species that were vascularly integrated into their host plants and transgene expression ranging from heterogeneous niches to more uniform patterns. Small molecules moved between symbionts and host vascular tissues, whereas larger proteins exhibited more restricted mobility. Post-transcriptional gene silencing signals moved freely throughout the symbiont and slightly into adjacent stem tissue. Under tested field and greenhouse conditions in potato and tomato, respectively, gall or symbiont formation had no negative impacts on plant growth or tuber and fruit yield. In vitro, symbiont cultures abundantly secreted recombinant protein into surrounding media. Together, these results establish symbionts as a modular, plant bioengineering platform capable of producing and potentially delivering biomolecules without modifying the host plant genome, providing a foundation for vascular-targeted therapeutics and phenotype modulation in crops.

Abstract The genus Crataegus (Rosaceae) exhibits remarkable taxonomic diversity in Iran, with seventeen recognized taxa distributed across contrasting ecological zones. In recent years, hawthorn has gained prominence as a valuable botanical resource, with applications spanning both herbal medicine and functional food development. Historically, various plant organs, particularly fruits, leaves, and flowers, have been employed in traditional remedies targeting cardiovascular disorders, including hypertension, arrhythmias, and other cardiac complications. These therapeutic properties are primarily attributed to the rich array of secondary metabolites characteristic of hawthorn, notably phenolic compounds and anthocyanin pigments, which underlie its antispasmodic and analgesic effects. We investigated the morphological, biochemical, and phytochemical diversity of eight Iranian Crataegus pontica ecotypes collected from geographically distinct regions. Ecotype origin and environmental conditions significantly influenced all measured parameters ( p < 0.05). Substantial variation was observed in fruit morphometrics, with CPE3 (Miyaneh) and CPE5 (Taleqan) producing the largest fruits, while CPE6 (Sanandaj) and CPE7 (Khorramabad) yielded considerably smaller ones. Biochemical profiling revealed marked ecotypic differences in total soluble solids, soluble carbohydrates, vitamin C, carotenoids, and anthocyanins, reflecting the profound influence of environmental conditions on primary and secondary metabolism. High-altitude ecotypes, particularly CPE3, CPE4 (Alamut), and CPE5, consistently exhibited the highest concentrations of total phenolics, total flavonoids, and antioxidant capacity. HPLC-based phenolic profiling identified chlorogenic acid, hyperoside, rutin, quercetin, and kaempferol as predominant compounds, with ecotype-specific accumulation patterns distinguishing high-antioxidant genotypes such as CPE5, CPE6, and CPE1 (Mahabad). Strong positive correlations among total phenolic content, total flavonoid content, and FRAP values confirmed phenolic compounds as primary determinants of antioxidant potential. Multivariate analyses classified the ecotypes into three functional groups: sugar-rich, large-fruited types (CPE3–CPE4); phenolic- and antioxidant-enriched types (CPE5–CPE6); and intermediate types with moderate metabolite profiles (CPE1, CPE2, CPE7, CPE8). Canonical correspondence analysis revealed altitude, precipitation, and temperature as key environmental drivers shaping phytochemical biosynthesis. We conclude that C. pontica exhibits substantial metabolic plasticity in response to environmental variation, with high-altitude ecotypes demonstrating superior phytochemical profiles as promising candidates for breeding programs and nutraceutical development.

Banana cultivation is increasingly challenged by limited land availability, climate variability, and declining resource-use efficiency, necessitating the adoption of precision-based production strategies. This review critically synthesizes recent advances in high-density planting (HDP), precision nutrient and water management, improved planting material, and other hi-tech interventions for enhancing banana productivity and sustainability. Evidence from experimental and multi-location studies indicates that HDP systems with plant densities ranging from 2,500 to 5,000 plants ha⁻¹ can increase yield by 19–79% over conventional planting, depending on cultivar, spacing, and management practices. Precision fertigation under HDP has been reported to reduce fertilizer use by 25–50% while maintaining or improving bunch weight, fruit quality, and economic returns. In addition, optimized planting geometry and resource management improve light interception, water-use efficiency, and overall system resilience. These approaches improve resource-use efficiency by reducing fertilizer and water inputs by approximately 25–50%, while enhancing economic returns through yield gains of 20–70% compared with conventional banana cultivation systems. This review highlights that integrating precision approaches with cultivar-specific recommendations offers a viable pathway for achieving sustainable productivity in banana cultivation, particularly under Indian and South Asian production systems, while also identifying key research gaps for future refinement. Graphical Abstract

This review explores the innovative approaches in the development of next-generation biopesticides, focusing on molecular and microbial strategies for effective control of fungal plant pathogens. As agricultural practices increasingly seek sustainable solutions to combat plant diseases, biopesticides have emerged as a promising alternative to chemical pesticides, offering reduced environmental impact and enhanced safety for non-target organisms. The review begins by outlining the critical role of fungal pathogens in global agriculture, emphasizing the need for novel control methods that can mitigate their detrimental effects on crop yields. Key molecular strategies discussed include the use of genetic engineering to enhance the efficacy of biopesticides, the application of RNA interference (RNAi) techniques to target specific fungal genes, and the development of bioactive compounds derived from natural sources. Additionally, this review highlights the potential of microbial agents, such as beneficial bacteria and fungi, in establishing biocontrol mechanisms that promote plant health and resilience. Through a comprehensive review of recent studies and advancements in the field, this manuscript illustrates how integrating molecular and microbial strategies can lead to the development of effective biopesticides tailored to combat specific fungal threats. The implications of these strategies for sustainable agriculture are discussed, alongside the challenges and future directions for research and implementation. Ultimately, this review aims to provide a thorough understanding of the transformative potential of next-generation biopesticides in the fight against fungal plant pathogens, contributing to the broader goal of sustainable food production.

ABSTRACT A severe leaf blight epidemic caused by Stemphylium vesicarium was observed on cultivated leek ( Allium porrum L.) in a commercial seed production field in Türkiye. The disease occurred in early summer 2025 during the second year of a biennial seed production cycle, where incidence reached 50%–75%. The extended cultivation period characteristic of seed production (12–18 months) likely served as a key epidemiological driver, enabling pathogen overwintering and extensive inoculum accumulation, in contrast to the shorter cropping period of annual vegetable production systems. The pathogen was identified as S. vesicarium based on morphological features and confirmed by maximum likelihood phylogenetic analysis of combined internal transcribed spacer (ITS) and glyceraldehyde‐3‐phosphate dehydrogenase ( gapdh ) gene sequences. Pathogenicity was verified through fulfilment of Koch's postulates using two representative isolates on healthy leek plants. This report constitutes the first confirmed occurrence of S. vesicarium on leek in Türkiye and demonstrates a shift in its epidemiological importance from a minor foliar pathogen in annual systems to the causal agent of a severe epidemic under biennial seed production conditions, highlighting the need for targeted surveillance and management strategies to mitigate disease risk in both seed and commercial leek production.

Anthracnose fruit rot, caused by Colletotrichum coccodes, is a major constraint to tomato (Solanum lycopersicum) production worldwide, leading to significant yield and postharvest losses. Conventional chemical control methods pose challenges such as pathogen resistance, environmental contamination, and high costs; hence, the need to explore eco-friendly alternatives. This study investigated the antagonistic potential of endophytic fungi — Trichoderma sp., Aspergillus flavus, Aspergillus niger, and Rhizopus sp., against C. coccodes disease of tomato under in vitro conditions. Endophytes were isolated from healthy tomato tissues collected from Adamawa and Gombe States, Nigeria, and identified morphologically. Dual culture assays were used to assess antagonistic interactions. Results showed that all endophytic isolates significantly inhibited the growth of C. coccodes (P < 0.05), though inhibition levels varied among species. Trichoderma sp. exhibited the highest antagonistic activity (up to 12.33 mm inhibition zone at day 7), followed by Rhizopus sp. (10.68 mm), A. niger (10.52 mm), and A. flavus (10.25 mm). Mechanisms observed included antibiosis, mycoparasitism, and competition for nutrients and space. The findings demonstrate that these endophytic fungi possess strong biocontrol potential against tomato anthracnose. Trichoderma sp., in particular, could be further developed as a biological control agent within integrated disease management programs. Future studies should focus on field validation and formulation of effective endophytic inoculants for sustainable tomato production.

A field experiment was conducted during 2025 (April–August) at Department of Horticulture, College of Agricultural Technology, Kullapuram to study the effect of foliar application of biostimulants on growth, yield and quality of marigold (Tagetes erecta L.). The petals served as an excellent source of xanthophylls, with lutein accounting for 80–90 % of the total content, underscoring its significance beyond floriculture. The experiment consisted of five treatments viz., Fish Amino Acid at 3%, Panchagavya at 3%, Seaweed Extract at 3%, Vermiwash at 3%, and Control, laid out in a Randomized Block Design with four replications. Among the treatments, foliar application of Fish Amino Acid at 3% markedly enhanced growth parameters such as plant height (63.22 cm), number of branches (24.19) and number of leaves (251.15). It also recorded the highest physiological traits, including chlorophyll (49.34 SPAD) and leaf area (9.07 cm²). Yield attributed were similarly improved, with earliest flowering (34.73 days), maximum flower number (48.84), greatest individual flower weight (20.03 g), highest flower yield plant-1 (978.27 g) and longest vase life (6.57 days). The findings confirmed that foliar application of biostimulants, particularly fish amino acid, was a highly effective method for improving the overall growth, yield, and quality of marigold.