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The short-wave and highly energetic ultraviolet‑C (UV-C) radiation has a disinfectant effect on various microorganisms. It is also known that UV‑C radiation can have an effect on stimulating plant defense. In this study, we used the phytopathogen Phoma lingam as a model organism to examine UV‑C at a wavelength of 254 nm application as an alternative to control this pathogen in Brassica napus. The aim of the study was to determine direct effects on the pathogen and indirect effects of stimulating the plant defense. Mycelia of P. lingam were grown in vitro and treated with different doses of UV‑C (0.015–1.57 kJ/m²). Mycelia diameters were then measured 1, 2, and 7 days after UV‑C treatment. In the in planta tests, cotyledons were injured by a needle and inoculated with 10⁶ spore suspension of P. lingam. To determine the direct effects the oilseed rape seedlings were treated with different UV‑C doses (0.2–1.5 kJ/m²) 1, 3, or 7 days after inoculation with P. lingam. To investigate the indirect effects the UV‑C treatments (0.2–1.5 kJ/m²) were applied 1, 3, or 7 days before inoculation with P. lingam. The in vitro experiments showed a significant reduction in mycelia growth on agar plates one and two days after UV‑C treatment. However, the fungal growth recovered; after 7 days no significant differences were detectable. The in planta results showed an effect on disease severity affected by the application time of UV‑C treatment and the applied UV‑C dose. UV‑C application 1 day before inoculation significantly increased the disease severity. Whereas, UV‑C treatment 7 days before inoculation with a UV‑C dose of 0.8 kJ/m² reduced the disease severity by 44%. If the UV‑C application was done after inoculation, the disease severity could be reduced by approximately 68% at a dose of 0.8 kJ/m² 1 day after inoculation. The results of the study show, that UV‑C treatment can stimulate plant defense and damage the pathogen directly.

Finger millet [Eleusine coracana L. (Gaertn.)] holds significant importance as a cereal crop in India due to its superior nutritional profile compared to that of other cereals. Salinity stress poses a substantial challenge to crop growth and yield. Silicon (Si) supplementation has been shown to mitigate both biotic and abiotic stresses in plants. This study investigated the impact of silicon supplementation (ranging from 0 to 25 ppm) on the tolerance of finger millet landraces to salinity stress induced by 200 mM NaCl. The addition of Si enhances seed germination and seedling growth in two finger millet landraces (ST-JA-SM: stress sensitive; ST-JA-WA: stress tolerant). Among the various Si concentrations tested, 10 ppm silicon was effective at alleviating salt stress. Compared with the ST-JA-SM landrace, the ST-JA-WA landrace exhibited greater osmolyte and carotenoid accumulation. Membrane lipid damage is more pronounced in the ST-JA-SM landrace, whereas antioxidative enzyme activities (SOD, CAT, APX, and GPX) are more prominent in the ST-JA-WA landrace. In conclusion, silicon amendment mitigates stress by activating the antioxidant enzyme machinery and reducing membrane damage in finger millet landraces.

Blue bull (Boselaphus tragocamelus), the largest antelope is causing significant crop losses in Punjab, India and farmers are continuously struggling to get rid of this menace. During present study, various mitigation tactics like physical barriers (such as barbed wire fencing, chain-linked fencing, electric fencing, and nylon net), mechanical and visual deterrent (such as bioacoustic and LED bulb, reflective ribbon) and repellents (such as phenyl, neelbo, and repellent based formulation i.e., RBF) were evaluated in different crops against the blue bull. Among physical barriers, chain-linked fencing, electric fencing, and nylon net, each at a height of ≥ 7 feet, had given promising results by providing complete protection for ≥ 2 year with a single application cost. Whereas barbed wire fencing and electric fencing at a height of 4–5 feet were not very effective against these animals, as they easily crossed fencings at lower height. All these physical barriers were not cost effective except in maize crop, which is the most preferred crop by blue bull. Bioacoustic device and reflective ribbon successfully reduced animal visits or percent damage and provided short term relief; however, after some time, animals developed habituation against these methods. Among chemical repellents, RBF significantly reduced the percent crop damage, was cost effective and remained operative for 21–69 days, while phenyl and neelbo exhibited effectiveness for only 7–14 days. Thus, this study suggests that while comprehensive damage prevention by physical barriers might be difficult or unaffordable for farmers, the use of repellent based formulation at vulnerable stages of crops can prevent damage for longer durations. Implementing a diverse set of management devices at the appropriate times can form an economically viable strategy to maintain blue bull damage within acceptable limits.

Bakanae disease is widespread in rice cultivation areas globally, presenting a significant challenge to basmati rice farming in India. Chemical seed and seedling treatment methods are commonly employed for managing bakanae disease, however, very less information is available on spray treatments. Our study aimed to assess the effectiveness of various fungicidal spray in field conditions for managing bakanae disease and their impact on basmati rice yield and related characteristics. Seven fungicides, along with a pathogen-inoculated control, were evaluated as foliar treatments during the Kharif season of the year 2021 and 2022. A combined analysis of data from two years showed that T₁ (Carbendazim 50% WP) had the lowest disease incidence at 44.68%, demonstrating a significantly high percentage disease inhibition of 44.08%. Following closely was T₄ (Tebuconazole 50% + Trifloxystrobin 25% WG) with a disease incidence of 50.00% and a corresponding percentage disease inhibition of 37.37%, while, maximum disease incidence of 79.84% was recorded in control treatment (T₈) followed by T₅ (Copper oxychloride 50% WP). Further, significantly high grain yield was obtained in Carbendazim 50% WP treatments (219.37 g/m²) followed by Tebuconazole 50% + Trifloxystrobin 25% WG (212.00 g/m²). Additionally, a quantitative polymerase chain reaction assay on harvested grains with Fusarium fujikuroi specific marker revealed least pathogen colonization in harvested seeds of Carbendazim 50% WP treatment (T₁), with a Ct value of 33.763 (copy no. 4.88E + 10), followed by Tebuconazole 50% + Trifloxystrobin 25% WG (Ct value 33.752, copy no. 4.94E + 10), conversely, Copper oxychloride (T₅) demonstrated the least effectiveness with highest pathogen load (copy no. 9.44E + 13). Based on our findings, we recommend the use of Carbendazim 50% WP or Tebuconazole 50% + Trifloxystrobin 25% WG for the management of bakanae disease as foliar spray (2 sprays) treatments (First spray after 15 days of transplanting; second spray at maximum tillering stage (around 25–30 days post I^st spray)) showing low AUDPC and high yield compared to inoculated control. Further, fungicidal spray reduced the infected seed percentage and carried less inoculum in next season. Therefore, these investigations will be valuable for management of bakanae disease after symptom appearance in field conditions. Findings could be further helpful in developing and validating an integrated approach to manage bakanae disease effectively in near future.

Soybean is a crucial crop in the modern world. Light plays a significant role in the growth and development of crops, as well as the prevailing environmental conditions during the growth period. This study aimed to investigate how fungal symbiosis affects the growth, biochemical properties, and grain yield (GY) of soybeans under various light intensities. The experiment was designed as split-plot based on randomized complete block design with three replications in the research farm of Sari Agricultural Sciences and Natural Resources University (SANRU) in 2022. The main factor consisted of five light intensities (20, 40, 50, 70, and 100% of natural light), and the sub-factor involved four levels of fungal inoculation (control, inoculation with Bjerkandera adusta (ST1) or Chaetomium globosum (SE2) fungi, and co-inoculation of ST1 + SE2). According to the results, as the light intensity decreased from 70 to 20%, the grain yield GY also decreased. The highest GY was observed at the 70% light intensity level with the symbiosis of two fungi, resulting in a significant increase of 50.4% compared to the control level. It seems that fungal symbiosis partially compensated for the light-imposed reduction. Furthermore, when the average intensity for light declined from 100 to 70%, the harvest index (HI) initially increased by 0.7% and then decreased. By comparison, the activity of catalase (CAT) and glutathione peroxidase (GPX) enzymes increased with higher shade intensity. However, fungal symbiosis at different light levels decreased the activity of these enzymes. In conclusion, the use of symbiotic fungi, particularly the combination of the two fungi, is recommended to increase soybean yield, especially in areas with lower light intensity.

In addition to competition, phytotoxic plant metabolites contribute to the weed-suppressing properties of cover crops, which could be the basis for the development of novel bioherbicides. We investigated the impact of five Cannabis sativa L. -derived neutral phytocannabinoids and an aqueous C. sativa tissue extract (HE) at six concentrations on the germination rate (GR) and seedling root length (RL) of Zea mays L., two monocotyledonous and two dicotyledonous weed species in laboratory Petri dish bioassays. Additionally, the effect of pre-emergence applications of HE, cannabidiol (CBD), and cannabidivarin (CBDV) formulations on GR and shoot dry matter (SDM) were examined in greenhouse pot studies. The effects of phytocannabinoids and HE were analyzed in dose-response curves. For the highest rates, the effects on GR, RL and SDM were calculated by ANOVA and HSD test (p < 0.05). HE exhibited the greatest suppression on GR and RL for all plant species in the Petri dish bioassay, with R_{GR, RL} exceeding −90%. Phytocannabinoids reduced mainly RL of all plants and decreased the GR of most weed species. Effects varied among plants and phytocannabinoids, with CBDV and CBD showing similar high inhibitory effects on RL as HE in the Petri dish bioassay. All pre-emergence applications resulted in a positive R_GR across all studied plants and in a positive R_SDM in Z. mays and Echinochloa crus-galli (L.) P. Beauv, whereas in the other weed species the R_SDM was negative. In conclusion, phytocannabinoids play a major role in weed suppression of HEs. CBDV and CBD are the most promising candidates for bioherbicide development especially against annual dicotyledonous weed species.

Drought and heat are recognized as the foremost abiotic stresses influencing plant growth and yield. In response to stressful conditions, plants undergo various physiological and biochemical modifications to enhance their resilience. Among these modifications, root exudates, comprising a diverse range of organic compounds, significantly impact plant resilience to drought and heat stresses. The soil microbiome plays a crucial role in mitigating drought and heat stress by enhancing plant resilience through various mechanisms, including nutrient acquisition, hormone production, and stress signal modulation. Its interaction with root exudates further amplifies these effects, as root exudates serve as key mediators in shaping microbial communities and promoting beneficial interactions. This review enunciates the crucial role of root exudates in conferring drought and heat stress tolerance, offering novel insights into the mechanisms, root structural changes, and physiological and biochemical adaptations. The role of microorganisms and their interaction with root exudates are explored to unveil the intricate network of interactions orchestrated by root exudates in stress adaptation, mitigation and resilience. In addition, this review examines the various physiological, abiotic, and biotic factors that impact the composition and dynamics of root exudates. Deciphering the complex interactions among these elements is essential to understanding the intricacies of plant stress responses. Furthermore, root exudate extraction techniques are briefed. Overall, this review aims to better understand and drive future research focused on integrating the role of root exudates, soil microbiome for improving adaptation, mitigation and resilience of crops to abiotic stresses such as drought and heat.

Salicylic acid (SA) and melatonin (MT) are recognized as growth regulators and antioxidants in fruits and vegetables. This study examined the impact of foliar SA (0, 1.5, and 2.5 mM) and MT (0 μM as control, 100 μM foliar application, and 100 μM irrigation) on Botrytis cinerea in bell pepper (Capsicum annuum Cv. California Wonder). Treatments were administered pre-fungal infection (2-leaf stage), with one pre-flowering and two post fruit-set applications. Inoculation occurred at flowering, 3 days post-flowering, and 6 days post-flowering. Both SA and MT significantly affected plant growth, leaf and fruit drop, and enzymatic activities in Botrytis-infected plants. 100 μM MT foliar application increased chlorophyll b content, while 100 μM MT irrigation raised phenylalanine ammonia-lyase (PAL) enzyme activity compared to control. SA elevated H₂O₂ levels, PAL and polyphenol oxidase enzyme activities, total dry matter, plant weight, fruit firmness, and plant height in infected pepper plants compared to control. The 1.5 mM SA concentration notably enhanced plant height, fruit firmness, weight, PAL, and superoxide dismutase enzyme activities. This study underscores the potent synergy of SA and MT in bolstering bell pepper resilience against B. cinerea.

Puccinia striiformis f.sp. tritici, also known as yellow rust, is one of the most destructive fungal pathogens in wheat-growing areas. Controlling this disease requires various techniques, such as chemical applications or developing resistant genotypes. The selection process of the lines is one of the most important steps in wheat breeding programs. Slow-rusting parameters are good indicators of resistance to rust and are useful in the selection of the genotypes with rust resistance. In this study, 787 durum and bread wheat genotypes were evaluated in the seedling stage and adult plant trials in the field during three growing seasons. They were evaluated through two slow rusting components: final rust severity (FRS), area under the disease progress curve (AUDPC).. Based on the seedling stage reactions, 575 genotypes were sown in the field to assess their adult plant reactions in 2021. Of these genotypes, 5.39% (31 genotype) were found to be very resistant, resistant, or moderately resistant. Thirty onegenotypes were screened under field conditions during the 2022 and 2023 growing seasons for verification. Fifteen genotypes (48.38%) have shown a high slow yellow rusting rate in both seasons. Results from this study will help breeders in developing yellow rust-resistant genotypes.

Weed control in perennial crops is especially difficult in the first phases of crop establishment. Hydromulch is a pasty blend that hardens after application and has so far been used specifically for weed control for experimental purposes only. In this work we tested blends based on recycled paper, gypsum and lignocellulosic materials (wheat straw, rice husk and used mushroom substrate) applied in three different locations of Spain under peach, vine, almond and artichoke plantations compared with an untreated control, manual weeding and herbicide (only in artichoke). The most frequent weed species were annual and perennial forbs. Lower weed soil cover compared to the untreated control was still relevant between 333 and 456 days after mulching (DAM), depending on the trial. In the artichoke trial the weed control effect was similar to that obtained with herbicides until the end of the assessments. Annual forbs were satisfactorily controlled with hydromulches (highest for Lamium amplexicaule with an efficacy of 88% based on soil cover); mean efficacy of perennials such as Cyperus rotundus and Convolvulus arvensis was lower ranging between 30 and 74% efficacy depending on the trial. Multivariate analysis showed an increase in wind-dispersed species such as Conyza sp. and Lactuca serriola over time. The capacity of the mulches to reduce weed soil cover for around one year can be useful in crops where weed control is crucial during that time, such as in plant nurseries and new plantations. Future research could focus improving the durability of the mulches to extend this period.