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To investigate the quantitative and qualitative yields of different rapeseed genotypes under optimal water supply and restricted irrigation regimes, a split plot experiment was arranged in a randomized complete blocks design with three replicates in the 2018–19 and 2019–20 growing seasons. The Main plots included irrigation regimes at three levels of optimal water supply regime, withholding irrigation from the beginning of flowering, and withholding irrigation from the beginning of silique setting. The sub-plots contained 11 Iranian rapeseed genotypes (Dalgan, Zafar, Sarigol, RGS003, Hyola4815, Hyola401, Zabol10, Jerom, Jerry, Julius, and Jacomo). The highest rapeseed seed yield (3463 kg ha⁻¹), oil content (43.09%), and oil yield (1492 kg ha⁻¹) were obtained from the optimal water supply regime. Drought stress (restricted irrigation from silique setting and flowering stages) decreased seed yield (28 and 49%), oil content (4 and 7%), and oil yield (31 and 52%). Fatty acids compositions of rapeseed genotypes differently responded to drought stress conditions. Restricted irrigation regimes enhanced the linolenic acid, erucic acid, and glucosinolate contents, while the palmitic acid, oleic acid, and linoleic acid content were reduced when the rapeseed plants were subjected to drought stress. Overall, our findings suggest that the Sarigol genotype due to acceptable seed and oil yield as well as high-quality oil under three studied irrigation regimes can be recommended for cultivation in arid and semi-arid regions like Iran.

Plant treatments with biocontrol agents to deal with biotic stress are widely reported, but the information regarding detailed action mechanisms of biocontrol and host response is rarely reported. This study investigated a biocontrol bacterial agent, Bacillus cereus, to manage tomato bacterial wilt (BW) disease. The in vitro antibacterial potential of B. cereus was assessed, followed by the ability of B. cereus to colonize tomato roots and induce host resistance. Additionally, we tested the application of B. cereus for managing tomato BW disease. In vitro investigations revealed the volatile mediated antibacterial activity of B. cereus, indicating that B. cereus produces antibacterial volatiles against R. solanacearum. The effectiveness of B. cereus in colonizing tomato roots was evaluated through its transgenic GFP-tagged strains and confirmed through qPCR analysis. It was found that the biocontrol bacterium successfully colonized the host root. The B. cereus concentration reached 9.37 × 107 at 48 h. The tomato plants under bacterial wilt stress, when treated with B. cereus, showed upregulation of genes linked to the plant defense system. The application of B. cereus to soil infested with R. solanacearum and planted with tomato plants reduced the pathogen population in the soil, resulting in a reduction in disease severity and improved plant growth. This study suggests the biocontrol potential of B. cereus to manage bacterial wilt disease.

Fruit processing waste from Annona mucosa Jacq. (Annonaceae) is an interesting source of biomass for development of ecofriendly botanical insecticides. Here, we evaluated the lethal and sublethal effects of the ethanolic extract prepared from seeds of A. mucosa (ESAM; major component = acetogenin bis-tetrahydrofuran rolliniastatin-1) against Chrysodeixis includens (Walker) and Anticarsia gemmatalis Hübner, two major defoliators of soybean crops. In the initial trial, ESAM showed activity comparable or superior to our positive control (Azamax® 1.2 EC, at recommended rate). The larvae of C. includes survived at higher levels than A. gemmatalis when exposed to ESAM. To cause mortality of 50 and 90% of the population of A. gemmatalis, 66.91 and 288.36 mg kg⁻¹ was needed, respectively, whereas, for C. includens, 452.38 and 885.70 mg kg⁻¹ were required, respectively. In addition, 27.23 and 51.01 h were needed to cause 50% of mortality against A. gemmatalis and C. includens, respectively. Under semi-field conditions (greenhouse), the aqueous emulsion of ESAM (pre-commercial formulation) and Azamax® 1.2 EC caused larval mortality above 95% for both pest species exposed to treated soybean plants. These results show that A. mucosa processing waste can be a source of promising botanical insecticides for the management of C. includens and A. gemmatalis, which are the main economically lepidopteran defoliators of soybean crops.

Cotton leaf curl disease (CLCuD) caused by Begomoviruses is a significant constraint to cotton production in Pakistan. Breeding for resistance is a key strategy to manage the disease. However, developing varieties with stable resistance and good fiber quality poses a challenge. Therefore, the study aimed to evaluate 71 cotton genotypes, including 67 accessions from Pakistan, three from Turkey and one from India, for resistance to CLCuD and yield traits at two locations (Faisalabad and Vehari) in Punjab. The association between traits was analyzed. A field trial was conducted using a randomized complete block design with three replications. Genotypes were evaluated for CLCuD severity, yield, and fiber traits. Correlation and factor analyses were done. The results showed significant variation among genotypes for CLCuD resistance and other characteristics. Some genotypes like FH-490 and FH-444 showed high yield, fiber length and strength, and tolerance to CLCuD. These could be directly used as parent lines in breeding programs. Furthermore, the factor analyses showed that at CRS, Faisalabad 3 PCs have eigenvalue > 1 with a contribution of 69.86%. However, at CRS, Vehari, these three components contributed 66.98% of the total variation in the cotton genotypes assessed for CLCuD, yield and fibre-related traits. Screening criteria were based on virus tolerance and performance of genotypes concerning superior boll number, sympodial branches and boll weight, and plant height. The study identified promising cotton lines with CLCuD tolerance and production traits. Character associations provide insights for breeding programs to develop cultivars with integrated disease resistance and superior fiber quality.

Grape is one of the most important fruit crop in the world. It is used for eating raw as well as for wine making in different countries of the world. In countries where consumer prefer seedless grape, there is more trend for growing table grapes. Seedless grapes are highly susceptible to fungal disease, so experiment was designed to screen different grape genotypes for anthracnose. Screening of different grape genotypes was done by artificial inoculation method as well as by using molecular markers. For phenotypic screening, inoculum was prepared form already infected leaves, and spore concentrations of 10⁵ spores/ml was applied on healthy leaves of different grape genotypes. Four days after inoculation disease symptoms were observed and disease intensity was measured by using disease scoring scale. Genotype Daakh is highly resistant to Anthracnose. Genotypes NARC Black, White vine, Himroid and King’s Ruby are considered as moderately resistant while genotypes Sugra One, Like Mount, and Vitro Black considered showed Susceptibility to anthracnose. Molecular screening was done by using SCAR makers linked to anthracnose. Screened disease resistant genotypes can be used for introgression of resistant gene into susceptible cultivars for development of cultivars with stronger resistance against anthracnose.

Among the various diseases occurring in the pecan tree crop, anthracnose, caused by species of the genus Colletotrichum, stands out. Biocontrol using Trichoderma presents as a promising measure to be used in disease control because it has a broad spectrum of action on phytopathogens, enables the activation of the defense system, and the promotion of plant growth, contributes to environmental sustainability and food security. This study aimed to investigate the in vitro antagonistic action of Trichoderma species on Colletotrichum, the etiological agent of anthracnose in pecan. The dual-culture assay and the inhibition test by volatile metabolites were performed with five species of Trichoderma (T. harzianum, T. koningiopsis, T. asperellum, T. tomentosum, and T. virens). Mycelial growth was evaluated daily until the seventh day. In the dual-culture assay, all species showed antagonist potential, inhibiting the mycelial growth of the pathogens from the third day onward. Trichoderma virens and T. tomentosum showed greater antagonist potential and stood out in the volatile metabolites.

The root-knot nematode (RKN) Meloidogyne javanica is one of the most economically important plant pathogens. Due to the high toxicity of chemical nematicides, the use of nematophagous fungi represents a promising alternative in nematode management. These biological agents offer a more sustainable and environmentally friendly approach to controlling plant parasitic nematodes (PPNs). The present study aimed to isolate and evaluate the nematicidal activity of three nematophagous fungi, viz., Paraconiothyrium cyclothyrioides, Aspergillus oryzae, and Lecanicillium psalliotae, against M. javanica under laboratory and greenhouse conditions. Three densities (1 × 10⁶, 1 × 10⁷, and 1 × 10⁸ spores/ml) of each fungus were used. In vitro, the results revealed that all the tested isolates were effective at inhibiting egg hatching and mortality in second juveniles (J2s). However, the mortality of J2s and hatching inhibition of eggs were proportional to the fungal concentration and duration of the exposure period. Among the isolates, A. oryzae at a concentration of 1 × 10⁸ spores/ml had the highest percentage of egg-hatching inhibition (95.5%) after 72 h of incubation. The highest juvenile mortality (100%) was recorded for P. cyclothyrioides at 1 × 10⁸ spores/ml after 72 h. The in vivo results showed that all the tested isolates significantly reduced the number of galls, egg masses, and eggs in tomato roots and J2s in soil. In general, the greatest reductions in the galling index (40%) and number of egg masses per root (88.8%) were recorded for P. cyclothyrioides at 1 × 10⁸ spores/ml, while the greatest reductions in the numbers of eggs (96.7) and J2s (98.1) were recorded for A. oryzae at 1 × 10⁸ spores/ml. Moreover, the treatment of soil with P. cyclothyrioides, A. oryzae, L. psalliotae, and NemGuard granules resulted in significant increases in root and shoot length; in contrast, a decrease in root fresh weight was observed. Therefore, these data suggest that the three isolates, viz., P. cyclothyrioides, A. oryzae, and L. psalliotae, are essential elements for integrated M. javanica control in tomato crops.

Quinoa (Chenopodium quinoa Willd) is highly resistant to a wide range of environmental stresses, including drought and salinity stresses. To evaluate the effect of bio-fertilizer and drought stress on the quantitative and qualitative traits of quinoa, an experiment was conducted on Research Farm, Shahed University in 2018. The main factors included irrigation interval 7, 10, 13, 16 days and the soil application of growth-promoting microorganisms (0, 0.1, 0.2, and 0.3% concentrations during the growth period) arranged in the sub-factor. The results showed that by increasing irrigation interval period, grain yield, 1000-grain weight and chlorophyll content decreased. The highest plant height (155.7 cm), leaves area (1543.6 cm²/plant), 1000-grain weight (2.69 g), chlorophyll a content (19.7 mg g⁻¹ FW), and seed potassium content (2.03%) were observed in 0.2% bio-fertilizer application under 13-day irrigation treatment. Application of 0.3% concentration bio-fertilizer under 13 and 16-day irrigation treatments was caused the highest grain yield (2.51 and 2.47 ton ha⁻¹) which had 14.34 and 12.95% increase compared to the control treatment. The highest percentage of accumulation of nutrients in the seed, including potassium, calcium and magnesium, was observed in the treatments of 0.3% biofertilizer with irrigation at intervals of 13 and 16 days. The results suggest that drought stress adversely affects quinoa quantitative and qualitative traits, and biofertilizer can improve quinoa plant tolerance todrought stress.

Sesame is a valuable oil plant due to its high-quality and stable oil. However, drought is a crucial factor that reduces agricultural productivity worldwide, having a destructive effect on different stages of sesame growth, causing a decrease in yield and yield components in sesame genotypes. Therefore, a study was conducted to investigate the effects of water stress and melatonin foliar spraying on sesame oil’s antioxidant properties and fatty acid compounds (Mina cultivar) during the years 2022–23. The study was done in a split plot based on a randomized complete block design with three replications. Drought stress in the form of irrigation interruption at different stages of plant development was implemented, with four control levels of full irrigation, interruption of irrigation at the stage of vegetative growth, reproductive growth, and vegetative + reproductive growth in the main plots. Melatonin foliar was done at three levels of 0, 0.5, and 1 mM in the sub-plots. During the physiological ripening stage, the seeds were harvested, and their oil was extracted. A gas chromatography device, equipped with a mass spectrometer, was used to determine the fatty acid profile of the oil. The results showed that drought stress significantly (P < 0.01) affected the amount of oleic acid, total unsaturated fatty acids, total fatty acids, and other components. The most abundant unsaturated fatty acids were oleic and linoleic acids. Drought stress caused a significant decrease in grain yield and oil percentage. In both conditions of irrigation interruption (vegetative and flowering stages), the total percentage of saturated and unsaturated fatty acids showed a significant decrease.

An increasing human population will lead to a higher demand for food, posing significant global challenges. To achieve sustainable agriculture, utilizing microorganisms is a promising alternative to chemical fertilizers and pesticides, minimizing risks to both the environment and the food chain. The utilization of Trichoderma fungus is considered one of the most effective eco friendly practices and has garnered significant attention due to its opportunistic nature and co mopolitan distribution. Notably, Trichoderma spp. in agroecosystems not only exhibit efficacy against phytopathogens and pests as biocontrol agents but also serve as valuable and convenient models in agricultural studies and environmental evaluations. Although these fungi are renowned for their numerous beneficial effects, they carry a potential risk of contamination to different species of mushrooms. In conclusion, this review sheds light on the multifaceted role of Trichoderma in both plant health and environmental contexts. This study provides a comprehensive overview of its mechanism of action and pathways, metabolite production, and checklists for biocontrol, formulation, and bioremediation. The current limited understanding of the effects of Trichoderma spp. in agroecosystems emphasizes the necessity for comprehensive studies to uncover its functions and roles. Conducting extensive research on the interactions of Trichoderma within diverse agricultural ecosystems will clarify its contributions to various aspects, including plant growth and well-being, nutrient cycling, soil fertility, disease suppression, microbial communities, overall sustainability, and potentially other ecosystem services.