فهرست مطالب

گیاه پزشکی - سال چهل و ششم شماره 4 (زمستان 1402)

فصلنامه گیاه پزشکی
سال چهل و ششم شماره 4 (زمستان 1402)

  • تاریخ انتشار: 1402/12/01
  • تعداد عناوین: 6
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  • حسین میرزایی نجفقلی*، سید مسلم موسویان، صدیقه غنایی، ندا روحانی صفحات 7-23

    استفاده از روش های جایگزین سموم شیمیایی، برای تولید محصولات ارگانیک از اهمیت بالایی در کشاورزی پایدار برخوردار است. یکی از این روش ها استفاده از عوامل زیستی میکروبی علیه بیمارگرهای گیاهی است. در پژوهش حاضر نیز اثر عوامل آنتاگونیستی P. fluorescens و T. harzianum علیه بیماری پژمردگی باکتریایی لوبیا با عامل Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff) در شرایط آزمایشگاه و گلخانه سنجیده شد. بدین منظور بعد از تهیه عوامل میکروبی، ابتدا اثر جلوگیری کننده از رشد باکتری Cff با دو روش کشت متقابل عوامل زیستی و مواد مترشحه آن ها در شرایط آزمایشگاه بررسی شد. سپس اثر این عوامل زیستی روی شدت و روند پیشرفت بیماری ایجادشده توسط Cff و همچنین شاخص های گیاه لوبیا در شرایط گلخانه، طی چهار تکرار و در قالب طرح کاملا تصادفی سنجیده شد. نتایج پژوهش حاضر نشان داد در شرایط آزمایشگاه عوامل آنتاگونیست P. fluorescens و T. harzianum به ترتیب 67/18 و 33/27 درصد و مواد مترشحه آن ها 16 و 67/13 درصد از رشد باکتری Cff جلوگیری کردند. در شرایط گلخانه تیمارهای P. fluorescens و T. harzianum و ترکیب این دو عامل با هم، به ترتیب 62/50 و 32/55 و 25/36 درصد، شدت بیماری را کاهش دادند. همچنین این سه تیمار به ترتیب 40 و 07/34 و 04/57 درصد، علائم بیماری را کاهش دادند. همچنین تیمار ترکیبی دو عامل زیستی بیشترین اثرگذاری را روی کاهش بیماری و افزایش شاخص های گیاه لوبیا نشان داد. لذا عوامل زیستی بکارگرفته شده می توانند به عنوان عوامل مهار زیستی بیماری پژمردگی باکتریایی و افزاینده رشد گیاه لوبیا باهدف کاربردی نمودن آن ها در مطالعات آینده موردتوجه قرار گیرند.

    کلیدواژگان: کنترل زیستی، آنتاگونیست، بیماری زایی، کورتوباکتریوم
  • محسن یزدانیان*، علیرضا رجائی صفحات 25-56

    تاکنون جهت کاربرد اسانس های گیاهی به عنوان عواملی بالقوه برای کنترل حشرات، تلاش های زیادی انجام شده است. تمایل به استفاده از ترکیبات گیاهی حشره کش برای کنترل آفات انباری همواره در حال افزایش می-باشد. در این پژوهش، سمیت تنفسی اسانس های هشت گیاه دارویی شامل گندواش (Artemisia annua Linnaeus)، زیره سیاه (Elwendia persica (Boissier) Pimenov & Kljuykov)، آویشن شیرازی (Zataria multiflora Boissier)، شاهسپرم (Tanacetum balsamita Linnaeus)، باریجه (Ferula gummosa Boissier)، مورد (Myrtus communis Linnaeus)، لیمو (Citrus limon (Linnaeus) Osbeck) و مرزنگوش (Origanum majorana Linnaeus) علیه تخم ها، لاروهای سن اول و حشرات کامل شب پره مدیترانه ای آرد (Ephestia kuehniella Zeller) و شب پره هندی (Plodia interpunctella (Hübner)) از طریق انجام آزمایش-های زیست سنجی و تجزیه پروبیت در شرایط آزمایشگاهی مورد بررسی قرار گرفت. ترکیبات شیمیایی اسانس ها نیز با استفاده از روش GC-MS شناسایی شدند. طبق نتایج، در هر دو گونه، اسانس گندواش بیشترین اثر تخم کشی (LC50 به ترتیب 12/58 و 55/51 میکرولیتر بر لیتر هوا) را داشت. مورد علیه شب پره مدیترانه ای آرد و گندواش علیه شب پره هندی بیشترین اثر لاروکشی را نشان دادند (LC50 به ترتیب 19/84 و 84/76 میکرولیتر بر لیتر هوا). اسانس مورد نیز بیشترین اثر کشندگی را علیه حشرات کامل هر دو گونه دارا بود (LC50 به ترتیب 19/54 و 62/45 میکرولیتر بر لیتر هوا). ترتیب کشندگی هشت اسانس علیه حشرات کامل هر دو گونه یکسان بود و حشرات کامل ماده در مقایسه با نرها متحمل تر بودند. همچنین، تخم ها، لاروهای سن اول و حشرات کامل شب پره هندی در مقایسه با شب پره مدیترانه ای آرد اندکی حساس تر بودند. فراوان ترین اجزای اسانس ها شامل گندواش: Camphor، 1,8-Cineole؛ زیره سیاه: α-Terpinolen، Limonene، Propanal, 2-methyl-3-phenyl-؛ آویشن شیرازی: Carvacrol، Terbutaline, tris(trimethylsilyl) ether؛ شاهسپرم: Carvone، (‒)-Thujanone؛ باریجه: β-Thujene، β-pinene؛ مورد: δ-3-Carene، 1,8-Cineole، Carvacrol؛ لیمو: Limonene؛ و مرزنگوش: (‒)-Terpinen-4-ol، γ-Terpinene بودند. اثرات کشندگی گزارش شده اسانس های گیاهی مختلف و نتایج حاضر نشان می دهند که برخی گیاهان مانند گندواش و مورد دارای ترکیباتی هستند که به عنوان جایگزین آفتکش های شیمیایی خطرناک، دارای قابلیت های زیادی می باشند و فرموله کردن آن ها می تواند به عنوان روشی کاربردی جهت جایگزینی حشره کش های شیمیایی مورد توجه قرار گیرد.

    کلیدواژگان: گیاهان دارویی، سمیت تنفسی، شب پره هندی، شب پره مدیترانه ای آرد، غلظت های کشنده
  • امین مقصودی، مهدی داوری*، شلاله مصلحی صفحات 71-89

    با توجه به اهمیت تولید گیاهان زینتی و خسارت نماتد مولد ریشه گرهی و قارچ عامل پوسیدگی ریشه در این گیاهان، مطالعه حاضر با هدف ارزیابی واکنش نه گیاه زینتی به نماتد Meloidogyne javanica و اثر هم افزایی Neocosmospora solani با نماتد بر روی گیاه زینتی فروکاکتوس انجام گرفت. برای این منظور، سوسپانسیون تخم و لارو M. javanica به عنوان مایه تلقیح نماتد روی گیاهان زینتی مورد استفاده قرار گرفت و برخی فاکتورهای رشدی گیاهان و تعداد گره در ریشه مورد بررسی قرار گرفت. هم افزایی دو بیمارگر قارچ و نماتد نیز روی برخی فاکتورهای رشدی فروکاکتوس با دو روش مایه‏زنی همزمان و غیرهمزمان ارزیابی شد. در گیاه میرتلو (پایه آبی) گره قابل ثبتی وجود نداشت. بر اساس مقایسات انجام یافته بین گیاهان مایه‏زنی شده با نماتد، بیشترین تعداد گره در ریشه مربوط به بگونیا و کمترین در اشوریا، فروکاکتوس و آلوئه ببری مشاهده شد. فاکتورهای رشدی مورد بررسی و شکل ظاهری نیز در اغلب گیاهان با آلودگی بالا تحت تاثیر قرار گرفته بود که بیشترین تاثیر در بگونیا مشاهده شد. در ارزیابی هم‏افزایی، نتایج هر دو روش نشان داد که تیمار فروکاکتوس شاهد و تیمار دارای نماتد، بالاترین طول اندام هوایی را داشتند و کمترین طول اندام هوایی نیز متعلق به تیمار مایه زنی شده با نماتد و قارچ بود. همچنین گیاهان شاهد بدون قارچ و نماتد، بالاترین و تیمار مایه زنی شده با نماتد و قارچ، کمترین طول و وزن ریشه را داشتند. به طور کلی، نتایج این پژوهش، قابلیت بالای نماتدهای مولد ریشه گرهی در ایجاد خسارت بر روی گیاهان زینتی را نشان داد. از طرفی، اثرات هم افزایی M. javanica و N. solani در افزایش خسارت روی فروکاکتوس نیز مورد تایید قرار گرفت. نتایج حاصل، ضرورت شناسایی و کنترل این بیمارگرها را در گلخانه‏های تولید گیاهان زینتی مشخص می نماید.

    کلیدواژگان: پوسیدگی ریشه، گیاهان زینتی، نماتد مولد ریشه گرهی، هم افزایی، Ferocactus horridus
  • فرشته قنبری، سالار جمالی*، جمالعلی الفتی، صدیقه موسی نژاد صفحات 91-103

    پژوهش حاضر در شرایط گلخانه، با ارزیابی مقاومت یازده هیبرید خیار (3×2، 4×6، 3×7، 5×3، 2×7، 3×4، 4×2، 2×6، 3×6، 7×6) و یک رقم تجاری نگین به عنوان شاهد نسبت به نماتد ریشه گرهی در قالب طرح کاملا تصادفی با سه تکرار به اجرا در آمد. نماتد روی گوجه فرنگی رقم حساس ارلی اوربانا خالص سازی، تکثیر و با استفاده از خصوصیات ریخت شناسی شناسایی گردید. در هر کیلوگرم خاک، گیاهچه های خیار با 2000 تخم و لارو سن دوم مایه زنی و پس از 10 هفته، شاخص های تولیدمثلی نماتد ارزیابی گردیدند. هیبریدها از نظر شاخص بیماریزایی تفاوت معنی داری با یکدیگر داشتند. با توجه به رتبه بندی تیلور و ساسر، هیبرید 2×6 با شاخص گال چهار، حساس و شاهد نگین، هیبریدهای 3×2، 6×4، 3×7، 5×3، 2×7، 3×4، 4×2، 3×6 و 7×6 با شاخص پنج، بسیار حساس و از نظر شاخص توده تخم، هیبرید های 5×3، 2×6 و 3×4 با شاخص سه، دارای مقاومت نسبی و هیبرید های نگین، 3×2، 6×4، 3×7، 2×7، 4×2، 3×6 و 7×6 با شاخص چهار، حساس بودند. با در نظر گرفتن فاکتور تولید مثل و شاخص گال، تمام هیبریدها حساس ارزیابی شدند. از نظر شاخص مقاومت بین هیبریدها تفاوت معنی داری وجود داشت و طبق شاخص مقاومت در روش کوزنبری و همکاران، هیبریدهای 5×3، 2×6 و 3×4 نسبتا حساس و سایر هیبریدها حساس بودند. وزن تر و خشک اندام هوایی، وزن تر ریشه و حجم ریشه به لحاظ آماری معنی دار شدند. هیبریدهای تولیدی نسبت به هیبرید تجاری نگین، از نظر مقاومت به نماتد برتری داشتند که پس از آزمایش های تکمیلی می توانند به عنوان جایگزین، مورد توجه واقع شوند.

    کلیدواژگان: خیار، شاخص گال، مقاومت، نماتد
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  • A. Rajabpour * Pages 1-6
    The strawberry spider mite, Tetranychus turkestanii (Acari: Tetranychiidae), is an important pest of many ornamental plants planted in urban green landscapes of Ahvaz and other cities of Khuzestan province, southwest Iran. Chemical control of herbivorous pests in urban environments has many limitations and concerns due to the daily and near contact of many citizens with these ecosystems. Therefore, choosing eco-friendly pesticides with appropriate effects plays an important role in developing integrated pest management (IPM) programs for pests. This study evaluated short- and long-term effects of some biorational pesticides, including azadirachtin, etoxazole and abamectin, against the mite under field conditions. The results indicated that all pesticides successfully decreased the spider mites' density compared to the control. Nonetheless, etoxazole demonstrated significantly high short and long-term effectiveness in reducing the mite population compared to the other treatments. The findings can be used to develop the IPM program for T. turkestanii in urban green landscapes.
    Keywords: Etoxazol, abamectin, azadirachtin, spider mite, urban pest
  • H. Mirzaei Najafgholi *, S.M. Moosavian Jadval Ghadam, S. Ghanaei, N. Rouhani Pages 7-23
    Background and Objectives

    Curtobacterium flaccumfaciens pv. flaccumfaciens is the cause of bean bacterial wilt (CFF) and a dangerous pathogen for bean fields. To date, no definitive control has been found for this pathogen. In sustainable agriculture, it is used to control plant pathogens by applying management methods related to preserving the environment and producing organic products. The use of biological agents such as Trichoderma fungi and Pseudomonas bacteria is among these management methods. Minimal research has been done worldwide on biological agents' effects on CFF. Therefore, the present research will investigate the effect of inhibiting the growth and activity of two biological agents , including Pseudomonas fluorescens and Trichoderma harzianum, against CFF in laboratory and greenhouse conditions.

    Materials and Methods

    First, the pathogenicity test of CFF was carried out on the greenhouse's Sadri variety pinto bean plant. Then, the effect of fungal and bacterial biological agents against the pathogenic agent was investigated by two methods of mutual culture and their secreted substances in laboratory conditions. By measuring the diameter of the transparent halo formed around the extract and spot culture of biological agents, the growth inhibition power of these biological agents against CFF was evaluated. In order to investigate the effect of these biological agents against bacterial wilt disease in greenhouse conditions, these biological agents and pathogens were propagated and expanded, and a standard suspension was first prepared from them. These suspensions were inoculated on the host plant using the spraying method. During 21 days, disease symptoms and bean plant indicators have been recorded. Then, the disease severity of progress under the influence of these biological factors was checked using the 0 to 4 scoring system. Also, the plant resistance type to the pathogen was evaluated using the 1-5 scoring system. The data obtained from the laboratory (inhibition percentage) and greenhouse (treatment changes, plant resistance, and plant indices) studies were analyzed in a completely randomized design using SPSS 21 software.

    Results

    In laboratory conditions, P. fluorescens and T. harzianum treatment prevented the growth of pathogenic bacteria CFF by 18.67 and 27.33%, with a diameter of the inhibitory halo of 14 and 20.5 mm, respectively. It was also found that a significant part of the inhibitory effect of P. fluorescens bacteria (about 85.70%) is related to the secreted substances of the bacterial cells. In contrast, in the biological fungus T. harzianum, the effect of the secreted substances was about 50.02%. The effect of biological factors on CFF in greenhouse conditions showed that these biological factors strengthen the defense reaction of bean plants against CFF. So, the sensitive reaction of the plant against CFF bacteria (with a disease severity of 83.13%) was transformed into a semi-resistant reaction by inoculating P. fluorescens and T. harzianum with the diseased plant. Also, the inoculation of the combination of these two biological factors made the plant resistant to pathogenic bacteria. Treatment of P. fluorescens+T. harzianum, by affecting CFF bacteria, was the best treatment in reducing the severity of the disease during 7, 14, and 21 days; the severity of the disease on these days was 21.87, 33.12, and 36.25%, respectively, which showed a significant difference with the disease severity index in infected treatment during these few days at the statistical level of 1%. Treatment of P. fluorescens+T. harzianum, with a disease severity index of 36.25% and a 57.04% reduction in disease severity, showed the most significant effect on the reduction of bean bacterial wilt disease.

    Discussion

    In the present study, the use of two biological agents, P. fluorescens and T. harzianum, showed significant controlling effects on CFF in laboratory and greenhouse conditions, and 57.04% reduced the severity of this disease in the bean plant. These two biological factors prevent the growth and spread of plant pathogens by using mechanisms such as the production of secondary metabolites, acidifying the environment, competing for food and space, colonizing and stimulating the plant to produce phytoalexin, proteins related to pathogens, salicylic acid, etc. Therefore, using these two biological agents as safe, effective, and durable biological control agents in sustainable agriculture against bean bacterial wilt disease is recommended.

    Keywords: Biological control, Antagonist, Pathogenicity, Curtobacterium
  • M. Yazdanian *, A. Rajaei Pages 25-56
    Background and Objectives

    To produce high-quality food and minimize risks from chemical applications, employing economically viable alternative methods without chemical-related drawbacks is vital. Plant essential oils (EOs) have garnered attention as potential insect pest control agents. The current study examines the lethal effects of plant EOs on the Mediterranean flour moth (Ephestia kuehniella Zeller) and the Indian meal moth (Plodia interpunctella (Hübner)).

    Materials and Methods

    This study examined the fumigant toxicity of eight Iranian pharmaceutical plant EOs: sweet wormwood (Artemisia annua), black cumin (Elwendia persica), Shirazi thyme (Zataria multiflora), costmary (Tanacetum balsamita), galbanum (Ferula gummosa), myrtle (Myrtus communis), lemon (Citrus × limon) and marjoram (Origanum majorana) against eggs, first instar larvae, and adults of P. interpunctella and E. kuehniella. Insects were maintained under controlled conditions at 27 ± 2 °C, 60 ± 5% R.H., and a photoperiod of 14L:10D. Gas Chromatography-Mass Spectrometry (GC-MS) was employed to identify the compounds present in the tested plant EOs. The lethal concentration (LC) values were estimated using probit analysis based on data obtained from preliminary and main bioassays.

    Results

    The predominant compounds (in term of %) identified in the EOs were as follows: A. annua: Camphor (41.388), 1,8-Cineole (13.431); E. persica: α-Terpinolen (31.622), Limonene (14.524), Propanal, 2-methyl-3-phenyl- (13.180); Z. multiflora: Carvacrol (60.593) and Terbutaline, tris (trimethyl silyl) ether (11.229); T. balsamita: Carvone (42.607), (‒)-Thujanone (17.600); F. gummosa: β-Thujene (34.234), β-pinene (22.371); M. communis: δ-3-Carene (30.549), 1,8-Cineole (19.580), Carvacrol (13.987); C. limon: Limonene (55.131), and O. majorana: (‒)-Terpinen-4-ol (34.138), γ-Terpinene (15.494). EOs exhibited comparable ovicidal activity against the eggs of both species. Notably, A. annua EO displayed the highest efficacy, with LC50 values of 58.12 μl/L air for E. kuehniella and 51.55 μl/L air for P. interpunctella. For E. kuehniella, the EOs of M. communis, Z. multiflora, and F. gummosa followed suit in terms of efficacy, while E. persica, O. majorana, T. balsamita, and C. limon EOs demonstrated the lowest ovicidal activity. Conversely, regarding P. interpunctella, the EOs of M. communis, F. gummosa, Z. multiflora and E. persica exhibited the next highest efficacy, whereas T. balsamita, O. majorana, and C. limon EOs displayed the least ovicidal activity. Eggs of P. interpunctella exhibited slightly greater sensitivity compared to those of E. kuehniella. The EOs of M. communis and A. annua demonstrated the highest efficacy against first instar larvae of both species, with estimated LC50 values of 84.19 and 76.64 μl/L air, respectively. Following closely, EOs of A. annua and F. gummosa exhibited notable effectiveness against first instar larvae of E. kuehniella, while EOs of M. communis and Z. multiflora showed similar efficacy against first instar larvae of P. interpunctella. Conversely, the EOs of C. limon, T. balsamita, O. majorana and E. persica displayed the least larvicidal activity against E. kuehniella larvae, whereas the EOs of O. majorana and E. persica demonstrated the lowest efficacy against P. interpunctella larvae. Consistent with the findings concerning the eggs, the first instar larvae of P. interpunctella demonstrated slightly greater sensitivity compared to those of E. kuehniella. The EOs exhibited similar lethal effects against adults of both species. Notably, M. communis EO exhibited the highest lethality against male and female adults of both species, followed by EOs of A. annua, E. persica and Z. multiflora. Conversely, EOs of C. limon, T. balsamita, F. gummosa and O. majorana displayed the least lethal effect. Interestingly, female adults showed greater tolerance compared to male adults. Moreover, similar to the observations with eggs and first instar larvae, adults of P. interpunctella displayed slightly greater sensitivity than those of E. kuehniella.

    Discussion

    The study findings highlight the significant lethal effects of various plant EOs, indicating promising alternatives to hazardous chemical pesticides. Iran's rich pharmaceutical plant flora contains diverse compounds, including volatile ones like EOs, which can be explored for their medicinal, insecticidal, fungicidal and other properties. The availability of formulations derived from complete plant EOs or their active components (i.e. insecticides, acaricides, fungicides and herbicides) in the market suggests the potential for developing more potent and environmentally friendly biorational pesticides through dedicated research in this field.

    Keywords: Pharmaceutical plants, fumigant toxicity, Plodia interpunctella, Ephestia kuehniella, Lethal concentrations
  • A. M. Jumaah, S. Azimi * Pages 57-69
    During a survey on the biodiversity of plant-parasitic nematodes in the Misan province, southeast Iraq, a population of Psilenchus hilarulus was discovered around the rhizosphere of okra. The study included the analysis of the morphological and morphometric characteristics of the species that were recovered. These characteristics were then compared to those of other populations that have been reported from other locations. The phylogenetic relationships of the Iraqi population of P. hilarulus with representatives of tylenchid taxa were reconstructed using the partial sequences of the small subunit (SSU), D2-D3 expansion segments of large subunit (LSU), and internal transcribed spacer (ITS) regions of ribosomal DNA, based on Bayesian inference. In the phylogenetic trees inferred from SSU and LSU sequences, the sequences of genus Psilenchus formed a clade separate from the representatives of Tylenchidae and Merliniidae. In the SSU tree, the Iraqi population occupied a placement inside a major clade that includes the sequences assigned to P. hilarulus, P. cucrumerus and Psilenchus sp. In LSU tree, new LSU sequences formed a clade with a major clade that includes sequences assigned to P. hilarulus, P. cucrumerus and P. vinciguerrae. The first ITS sequence of the genus, the ITS rDNA of the Iraqi population of P. hilarulus, was utilized to reconstruct and analyze the corresponding phylogenetic tree. This appears to be the initial documentation of P. hilarulus emerging from Iraq.
    Keywords: ITS rDNA, LSU rDNA, Misan province, Phylogeny, SSU rDNA
  • A. Maghsoudi, M. Davari *, Sh. Moslehi Pages 71-89
    Background and Objectives

    Root-knot nematodes (Meloidogyne spp.) are amongst the most important plant-parasitic nematodes. These nematodes, which bind the roots of sensitive plants, are obligate parasites of plants. Numerous pathogens, including nematodes, fungi, bacteria, and viruses, cause damage to ornamental plants. Damage caused by these pathogens includes crown and root rots, cankers, and leaf blotches, among others. Given the importance of ornamental plant production and the detrimental effects inflicted by root-knot nematodes and root rot fungi on these plants, the current investigation aimed to assess the response of nine ornamental plants to the nematode Meloidogyne javanica. Additionally, the study sought to determine whether Neocosmospora solani, in conjunction with the nematode, could induce a synergistic effect on Ferocactus.

    Material and Methods

    The response of nine ornamental plants to the root-knot nematode was examined in the present study. Upon isolation from the crowns and roots of different cacti varieties grown in greenhouses containing ornamental plants in Ardabil province, the rot fungus was determined to be Neocosmospora solani. The M. javanica population was cultivated in the Plant Pathology Laboratory of Azarbaijan Shahid Madani University. A suspension of M. javanica eggs and larvae was utilized to inoculate ornamental plants with nematodes. To assess the plants' response to the nematode, several plant growth factors and the quantity of knots on the roots were examined. The present study also assessed the synergistic impacts of two nematode and fungal pathogens on specific growth factors of Ferocactus. Both simultaneous and non-simultaneous inoculation techniques were utilized.

    Results

    Among the plants with knots on the roots, except for tiger Aloe, in the rest of the investigated plants, there were significant differences among the treatments. Based on the comparisons between plants inoculated with nematodes, the highest number of knots was observed on the roots of Begonia plants and the lowest in Echeveria, Ferocactus and Tiger aloe. Notably, Tradescantia spathace was excluded from the analyses as a result of significant nematode damage and subsequent plant mortality. Based on the absence of any damage observed on the shoots and roots of the control plants of this species, it can be categorized as one of the Meloidogyne-sensitive plants. The growth factors examined in plants were similarly impacted in the majority of the plants that sustained significant damage, with begonia plants exhibiting the most pronounced effect. We observed the presence of diminutive, pallid flowers as well as a reduction in the mass of the roots and aerial components in the spotted begonia. Notwithstanding a minor aberration in the morphology of certain roots and aerial organs, no knots of significance were detected in Myrtillocactus. There were no discernible differences in plant growth factors between the control and inoculated plants; therefore, this particular plant can be deemed the most resistant to Meloidogyne among all the plants that were examined. Given that this plant is frequently utilized as a basal component in grafted cacti, this result may prove to be extremely beneficial. In relation to the synergistic assays conducted on the Ferocactus plant, the outcomes of both approaches demonstrated statistically significant differences among the treatments as determined by variance analysis for all the characteristics under investigation, namely shoot length, shoot weight, root length, and root weight. The treatments were inoculated with nematodes, and the control group exhibited the greatest shoot length. These treatments exhibited the shortest shoot lengths when inoculated with nematodes and fungi. The treatments containing nematode and fungus resulted in the shortest root length and weight, while the control plants devoid of nematode and fungus exhibited the greatest root length and weight.

    Discussion

    Overall, the findings of the current study demonstrated that root-knot nematodes have a significant capacity to inflict damage upon the ornamental plants under investigation. However, it was also confirmed that M. javanica and N. solani have synergistic effects on Ferocactus plant damage. The results validate the importance of promptly detecting and managing these organisms within greenhouse environments where ornamental plants are cultivated. Therefore, before the beginning of the infection and with the early detection of these diseases, it is possible to prevent the spread and damage caused by the root-knot nematode and root rot fungus in ornamental plants by using integrated management.

    Keywords: Ferocactus horridus, Ornamental Plants, Root Rot, Root-knot Nematode, Synergism
  • F. Ghanbari, S. Jamali *, J. Olfati, S. Mousanejad Pages 91-103
    Background and Objectives

    Cucumber (Cucumis sativus L.) holds significant agricultural importance in Iran, occupying extensive cultivation areas. Greenhouse conditions favor the proliferation of numerous pests and diseases affecting cucumber growth. Root-knot nematodes inflict yearly damage on cucumber farmers and producers, particularly in tropical and subtropical regions. Cucumbers are susceptible to various plant-parasitic nematodes, with Meloidogyne species, notably root-knot nematodes, posing significant threats. Controlling the nematode is challenging due to its wide host range, short life cycle, high reproductive rate, and parasitism. While chemical control remains prevalent for nematode population management, growing public concern over the environmental and human health impacts of nematicides is driving efforts to restrict their usage. Employing resistant varieties either independently or in conjunction with other strategies is increasingly recognized as a highly effective means of nematode control. Resistant plants prevent the need for long-term rotations and are highly suitable for sustainable agriculture. Consequently, the development of new cucumber varieties and hybrids and the assessment of their resistance can be applied in integrated nematode management. Hence, this research aims to evaluate the resistance of cucumber hybrids to root-knot nematodes (M. incognita) under greenhouse conditions.

    Materials and Methods

    Soil and root sampling was undertaken from cucumber cultivation sites in Guilan province. Egg masses were then introduced to the root systems of tomato seedlings, specifically the Early Urbana variety, at the two to four true leaf stage. Subsequently, these seedlings were nurtured for 45 to 60 days under greenhouse conditions. Identification involved the analysis of perineal patterns alongside morphological and morphometric traits of second-stage juveniles. Staining of female nematodes in root tissue was accomplished using the Hartman and Sasser method. Multiple consecutive inoculation cycles were executed on susceptible tomato plants to cultivate a substantial and uncontaminated nematode population. Seed germination took place in Petri dishes, with transfer to individual pots containing a mix of perlite and coco peat in equal measures after 48 hours. These pots were then randomly distributed within the greenhouse, with subsequent maintenance performed as required. The experiment followed a completely randomized design with three replications. Ten weeks post-inoculation, nematode-related parameters, such as the count of galls and egg masses using the Taylor and Sasser method, alongside the number of second-stage juveniles in the soil using the Barker method, were assessed. Subsequently, statistical analysis was carried out utilizing SAS 9.0 software following data normalization. Mean comparisons were conducted using the Tukey test.

    Results

    The results showed significant differences in some traits of the hybrids treated with nematodes. Variance analysis revealed no significant differences in specific indicators, including gall count, egg sacs, eggs, second-stage juveniles in the soil, reproduction factor, as well as fresh and dry shoot and root weights across the assessed hybrids. However, significant differences were observed among the growth indices of plants, particularly in fresh and dry shoot weight, fresh root weight, and root volume. The mean weight of the aerial parts in the control was 103.66 g. Hybrid 5×3 exhibited the highest reduction, with a weight of 63.33 g, reflecting a 38.9% decrease compared to the control. Conversely, hybrid 7×6 showed the least disparity, with a weight of 100 g and only a 3.53% reduction. Notably, significant differences were evident in gall index, egg mass index, resistance index, root dry weight, and root length. According to the Taylor and Sasser ranking for determining gall and egg masses indices, hybrid 2×6 exhibited sensitivity, while the remaining hybrids were classified as very sensitive. Regarding the egg masses index, hybrids 5×3, 2×6, and 3×4 displayed relative resistance, whereas the other hybrids were categorized as sensitive. Evaluation based on the reproduction factor and gall index indicated that all hybrids were classified as sensitive.

    Discussion

    The study concluded that none of the hybrids exhibited significant resistance indices. However, hybrid 2×6 demonstrated statistical significance in gall index, egg masses, and resistance, while hybrid 2×7 displayed superiority over the control variety in terms of larval count, egg count, and dry shoot weight. Consequently, pending further complementary experiments, these hybrids may be regarded as promising replacement candidates.

    Keywords: Cucumber, Gall index, resistance, Nematode