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This study investigates the biocontrol efficacy of enzymatic extracts from specific strains of Pseudomonas aeruginosa (strain Dokkala) and Bacillus cereus (strain B613) to assess their impact on various stages of the potato cyst nematode, Globodera pallida eggs, juveniles and cysts. In vitro assays demonstrated that enzymes from strain Dokkala significantly reduced the number of cysts by up to 49%, while achieving 68% mortality in juveniles and 55% in eggs after 10 days of incubation. Similarly, strain B613 exhibited a nematicidal effect of 55% and 44% for chitinase and protease, respectively, on juveniles after the same incubation period. Notably, a synergistic interaction between the enzymes from both strains led to an enhanced nematicidal effect beyond individual applications, surpassing 68% in juveniles. The study underlines the potential of these bacterial enzymes as a sustainable alternative to chemical nematicides, combining for the first time P. aeruginosa and B. cereus against G. pallida, offering a promising strategy for managing potato cyst nematodes in agricultural settings. This approach aligns with the growing need for environmentally friendly pest control methods, contributing valuable insights into the potential of microbial enzymes in integrated pest management.

Spodoptera litura (Lepidoptera: Noctuidae) is an important pest across a wide range of cropping industries. Due to increasing chemical resistance being displayed by this pest, the majority of conventional pesticides are now ineffective in controlling its populations. Therefore, it is essential that new target sites are identified to aid in the development of novel and efficient pest management strategies. To obtain a comprehensive understanding of transcription regulation in S. litura at various developmental stages, we created 33 libraries that comprised three replicates of nine development stages and two genders. The results of differentially expressed transcripts showed a wide difference within S. litura during its developmental process, and some genes were specifically expressed in certain developmental stages. To understand the function of gene expression at different developmental stages, all DEGs were mapped in the GO and KEGG databases. The results showed that the DEGs produced in the comparison between male pupae (MP) and sixth-instar larvae (L6) had the most abundant GO enrichment, followed by comparison of female pupae vs L6 and first-instar larvae (L1) vs eggs (E); L1 vs E had the most abundant enrichment with up-regulation in KEGG database, followed by the fifth instar larvae vs forth-instar larvae (L4); L4 vs third-instar larvae (L3) had the least abundant enrichment in the 10 comparative groups, followed by L3 vs second-instar larvae. This study analyzed the genetic variation within S. litura during its developmental process, to potentially identify an appropriate life stage at which control methods could be deployed to disrupt its development.

Pepper (Capsicum spp.) is widely cultivated throughout the globe due to its diversified use in food (vegetable, spice, paprika, oleoresin) as well as non-food (industrial, pharmaceutical) sectors. Despite its economic value, pepper cultivation faces significant challenges due to bacterial diseases such as bacterial wilt, bacterial spot, bacterial canker, and bacterial soft rot globally. Existing chemical, and biological control strategies have numerous limitations such as the emergence of new resistant strains, negative environmental impact, and lack of user-friendly formulations. Hence, host plant resistance offers a sustainable solution restricting the use of harmful chemicals. Although significant progress has been achieved in the identification and utilization of bacterial wilt and bacterial spot-resistant genotypes, newly emerging threats in pepper like bacterial canker and bacterial soft rot require immediate attention. This article focuses on genetic resources, inheritance patterns, and molecular markers associated with resistance to bacterial diseases in pepper to develop resistant pepper varieties, hybrids, or rootstocks.

In the absence of new herbicides on the market, adding adjuvants into the tank with herbicides is a strategy for increasing efficacy. In our research, we tested whether there are differences in weed control as influenced by the original nicosulfuron formulation and a generic counterpart. In this study, we tested the addition of two commonly used adjuvants: ammonium-sulfate (AMS) and non-ionic surfactant (NIS). In a three-year experiment, based on a percentage of biomass reduction and canopy cover, these results showed no differences in any treatments when comparing the original versus generic nicosulfuron. However, adding an NIS increased efficacy, while adding AMS decreased herbicide activity. The average percentage reduction of biomass in this study was about 80%, implying that using solely nicosulfuron as aceto-lactate synthase inhibiting herbicide is not a good solution in weed control in maize and that other methods for weed control should be considered and integrated, in order to increase weed control efficacy.

The Mediterranean fruit fly, Ceratitis capitata, is a severe pest of orchards around the world and has recently invaded orchards in northern Iran. The soil-dwelling larvae of this pest are amenable to control by entomopathogenic nematodes (EPNs) but have been studied only in tropical orchards. To assess the biocontrol potential of Iranian strains of two EPN species, Heterorhabditis bacteriophora (boj) and Steinernema carpocapsae (z1), for control of C. capitata, we conducted a series of laboratory and a field experiment. the highly virulent nature of S. carpocapsae towards C. capitata larvae was apparent, demonstrating near 80% efficacy at a concentration of 25 infective juveniles (IJs) per cm² in loam soil, surpassing the 40% control exerted by H. bacteriophora. When tested at temperatures of 19, 25, and 30 °C, Steinernema carpocapsae caused the highest mortality at 25 °C (85%) and the lowest at 30 °C (58%), whereas control by H. bacteriophora was not affected by temperature (44–50%). Both EPN strains caused higher mortality in loam and clay loam soils than in sandy loam. Heterorhabditis bacteriophora produced significantly more IJ progeny from infected larvae than S. carpocapsae. Both S. carpocapsae and H. bacteriophora caused only moderate mortality of C. capitata pupae with 38 and 27%, respectively, at a rate of 50 IJs/cm². Under field conditions, both species caused significant mortality when sprayed at a concentration of 25 IJs/cm² on soil and tangerine fruits infested with C. capitata larvae, with 45 and 69% mortality for H. bacteriophora and S. carpocapsae, respectively. Our findings suggest that S. carpocapsae (z1) could be implemented as a biological agent in a C. capitata management program in temperate climate orchards.

Potassium content is an important standard for measuring tobacco quality. However, research on the mechanism of low potassium tolerance in cigar tobacco (Nicotiana tabacum L.), which differs from regular tobacco, did not draw researchers’ attention. This study evaluated the tolerance to low potassium of 23 cigar varieties by investigating 20 phenotypic and physiological indicators. Utilizing principal component analysis, membership function analysis, and cluster analysis, the research comprehensively identifies the tolerance of cigar tobacco varieties to low potassium. The results indicate that the tolerance to low potassium of cigar tobacco is complex and varies among different traits and varieties. The current study identified six crucial indicators for measuring tolerance to low potassium in cigar tobacco leaves, including plant height, maximum leaf area, leaf surface area, total root absorption area, and active root absorption area. Based on the comprehensive evaluation value D of the low potassium tolerance coefficient for these six indicators, the study classified the 23 cigar varieties into four categories: one low potassium-sensitive variety, five low potassium-low tolerance varieties, eleven low potassium-relative tolerant varieties, and six low potassium-tolerant varieties. These research outcomes significantly contribute to the elucidation of tolerance to low potassium in cigar tobacco, facilitating the evaluation, screening, and cultivation of cigar tobacco varieties resilient to low potassium conditions. Additionally, this study lays the foundation for exploring scientific issues such as how plants can effectively utilize potassium, the mechanism of potassium ions in plants, the improvement and development of cigar quality, the enhancement of potassium utilization efficiency, and conservation of limited potassium resources to ensure long-term potassium availability.

The purpose of this study was to determine the agro-morphological, physiological, and transcriptional characteristics of ethyl methane sulfonate (EMS)-mutagenized M₃ alfalfa (Medicago sativa L.) mutants grown for 24 days under water deficit conditions following the first cutting at the blooming bud stage. Drought stress generally reduced all agro-morphological parameters measured. Cutting stress significantly reduced total chlorophyll contents of all genotypes, with the exception of mutant X20. Significant changes occurred in the levels of ascorbate peroxidase (APX), lipid peroxidation (TBARS), glutathione reductase (GR), superoxide dismutase (SOD) and crude protein levels. Drought stress considerably elevated GR levels in irrigated control (C1) and unirrigated control (C2) plants. In contrast to the other genotypes studied, mutant X20’s crude protein level increased significantly after the first cutting under 24 days of water deficit conditions, compared to the level found before cutting. The expression profiles of Medicago truncatula Response to Desiccation 2 (MtRD2) and Medicago sativa proline dehydrogenase (MsProDH) genes differed based on the plant genotype and duration of drought stress. Drought stress increased MsProDH gene expression in X20, X50, and C2 plants by 4.57, 14.8, and 20.65 times, respectively. The findings of the expression study indicated that the MtRD2 gene may play a key role in stress reduction rather than drought stress per se. The results of this study revealed that cutting and drought are two independent stress variables that should be evaluated separately when evaluating genotype response to both irrigated and unirrigated growing environments in alfalfa.

The study aimed to investigate the impact of Glycine Betaine (GB), Salicylic Acid (SA), and Ascorbic Acid (AsA) on the yield and quality of cotton plants during the 2021 and 2022 growing seasons at Harran University’s experimental fields in Şanlıurfa, Turkey. The research employed a split-plot design with three replications. Main plots were assigned for chemical applications (GB, SA, and AsA), while subplots were designated for different irrigation levels (IW₁: Kp;1.00, IW₂: Kp;0.75, and IW₃: Kp;0.50). The study revealed that crop evapotranspiration varied between 400 to 728 mm in 2021 and 489 to 841 mm in 2022. The application of GB, SA, and AsA increased irrigation water productivity, especially under drought stress (DS) conditions, indicating the potential to enhance water productivity in cotton plants. DS resulted in significant reductions in various parameters such as plant height, shoot fresh weight, shoot dry weight, SPAD values, boll number, boll weight, cotton yield, ginning outturn, and 100-seed weight. However, the application of GB, SA, and AsA led to statistically significant (P ≤ 0.05) increases in these parameters under DS. Contrary to this, the application of GB, SA, and AsA did not have a statistically significant effect on ginning outturn and 100-seed weight under DS. GB, SA, and AsA applications demonstrated effectiveness in enhancing drought tolerance in cotton. These applications can help reduce yield losses in cotton production under drought conditions. Importantly, by conserving water and preventing yield losses, they offer valuable support to the textile industry.

The impact of climate change has led to growing global concern about the interaction of temperature and xenobiotics in agricultural toxicological studies. Thus, lethal, sublethal and transgenerational effects of six insecticide formulations used in the management of the stink bug complex in soybean crops were evaluated firstly on different life stages of the parasitoid Telenomus podisi Ashmead at three levels of temperature. Telenomus podisi adults in F₀ generation, when exposed to insecticides including acephate, spinosad and thiamethoxam + lambda-cyhalothrin, showed accumulated mortality of 100% at 15, 25 and 30 °C. On the other hand, methoxyfenozide + spinetoram caused average mortalities of 88.75% at 15 °C, 38.75% at 25 and 30 °C. The mortality caused by chlorfenapyr was increased by 70% with increasing temperature. Surviving adults in lethal toxicity bioassay did not show differences in egg parasitism of F₀ generation and emergence of F₁ generation at 15, 25 and 30 °C; however, the insecticide formulation based on methoxyfenozide + spinetoram showed the lowest level of parasitism and emergence. Our results demonstrated significant changes in the sex ratio as the temperature increased, but no differences were observed when compared with the insecticides tested. A significant interaction between insecticides and temperatures was discovered by contaminating the host’s parasitized eggs, corresponding to the pupal stage of T. podisi. Generally, the highest emergence reduction values were found at 30 °C. Our results highlighted the temperature-dependent impact of synthetic insecticides on parasitoids, which should be considered in toxicological risk assessments, under integrated pest management and climate change scenarios.

The health and selectivity of green cane to herbicides applied in the field can be attributed to various factors, including the harvest season, soil texture, sugarcane straw on the soil surface, the selection of the correct herbicide molecule, and the appropriate timing of application. Our study aims to evaluate sugarcane development across multiple experimental sites in relation to herbicide management. We consider different amounts of sugarcane straw (0, 5, 10, and 15 Mg ha⁻¹) in conjunction with the beginning, middle, and end of the harvest season, across varied edaphoclimatic conditions. Five experimental sites were chosen for evaluation over two years. The primary treatments involved straw amounts placed on the soil surface: 0, 5, 10, and 15 Mg ha⁻¹. Secondary treatments included herbicide application and no herbicide application. Parameters measured were phytotoxicity percentage and sugarcane yield. Our findings indicate that higher amounts of sugarcane straw (10 or 15 Mg ha⁻¹) on the soil surface, especially in sandy soils and areas harvested early in the season, result in a higher incidence of phytointoxication compared to scenarios involving clayey soils or other harvest periods. However, phytointoxication injuries did not reduce sugarcane yield, demonstrating selectivity and health for sugarcane in the green cane under our evaluated conditions.