Organic Amendments Increase Growth, Resistance, and Management of Root-Knot Nematode in Arachis hypogaea L. PDF

Pakistan Journal of Nematology Research Article Organic Amendments Increase the Growth, Resistance and Management of the Root-Knot Nematode, Meloidogyne arenaria in Arachis hypogaea L. Eman Abdelrazik1, Sahar H. Abdel-Baset2*, Abdelghafar M. Abu-Elsaoud3,4 and Shimaa M.A. Mohamed5 Departm...

Pakistan Journal of Nematology Research Article Organic Amendments Increase the Growth, Resistance and Management of the Root-Knot Nematode, Meloidogyne arenaria in Arachis hypogaea L. Eman Abdelrazik1, Sahar H. Abdel-Baset2*, Abdelghafar M. Abu-Elsaoud3,4 and Shimaa M.A. Mohamed5 Department of Botany and Microbiology, Faculty of Science, Suez University, 43511, Suez, Egypt; 2Department of Nematode 1 Diseases Research, Plant Pathology Research Institute, Agriculture Research Center, Giza, Egypt; 3Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, 11623, KSA; 4Department of Botany and Microbiology, Faculty of Science, Suez Canal University, Ismailia, 41522, Egypt; 5Department of Plant Production, Faculty of Environmental, Agricultural Sciences, Arish University, Arish, Egypt. Abstract | One of the greatest barriers to the production of peanut crops is plant-parasitic nematodes, which are the most destructive pathogens that affect peanuts globally. A survey of plant-parasitic nematodes (PPNs) in peanuts was conducted in Ismailia, Egypt. The host suitability of four Egyptian peanut cultivars for Meloidogyne arenaria cultivation under greenhouse conditions was also examined. Additionally, the effects of fulvic acid, compost, and cattle manure, either alone or in combination, as well as the nematicide Fosthiazate 10% G, on peanut growth, biochemical parameters, and the management of M. arenaria were examined. Seven PPN genera were linked to peanut roots according to the results. These genera were Meloidogyne. (88%), Tylenchorhynchus (25%), Helicotylenchus (23%), Rotylenchulus and Xiphinema (4%, each), in descending order. The findings indicated that peanut cvs. Ismailia-1 and Ismailia-2 were susceptible; however, Giza-5 and Giza-6 were highly susceptible to M. arenaria. The growth of peanuts and the formation of nodules were greatly enhanced by organic amendments, either alone or in combination, improving plant tolerance. The organic amendment treatments significantly reduced the number of galls, root egg masses/root and nematode population ( J2s) in the soil, while fosthiazate resulted in the greatest reduction. All the treatments markedly increased the enzymatic antioxidant enzyme activity in peanuts relative to the control, i.e., peroxidase, catalase, phenylalanine ammonia-lyase, chitinase, β-1,3 glucanase, and total phenolic activities. The integration of several techniques, including fulvic acid, compost, and cattle manure, might have a substantial effect on enhancing peanut development, biochemistry, and the ability to resist and control M. arenaria. Received | September 22, 2024; Accepted | October 31, 2024; Published | November 15, 2024 *Correspondence | Sahar H. Abdel-Baset, Department of Nematode Diseases Research, Plant Pathology Research Institute, Agriculture Research Center, Giza, Egypt; Email: [email protected] Citation | Abdelrazik, E., Abdel-Baset, S.H., Abu-Elsaoud, A.M. and Mohamed, S.M.A., 2024. Organic amendments increase the growth, resistance and management of the root-knot nematode, Meloidogyne arenaria in Arachis hypogaea L. Pakistan Journal of Nematology, 42(2): 146-161. DOI | https://dx.doi.org/10.17582/journal.pjn/2024/42.2.246.161 Keywords | Arachis hypogaea, Meloidogyne arenaria, Organic amendments, Peroxidase, Catalase, Chitinase, Growth parameters Copyright: 2024 by the authors. Licensee ResearchersLinks Ltd, England, UK. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/4.0/). December 2024 | Volume 42 | Issue 2 | Page 146  Pakistan Journal of Nematology Introduction nematodes and enhancing plant growth (Edussuriya et al., 2023; Hal et al., 2023). According to Abdel- G roundnut, or peanut (Arachis hypogaea L.), belongs to the family Fabaceae and is grown in more than 82 nations globally. Owing to the high nutritional Monaim et al. (2018) an organic amendment promotes plant health by having positive effects on soil nutrition, soil physics, and soil biology, which value of oils, proteins, calories, and vitamins, it is a lower the nematode population. Numerous studies crop of commercial significance that produces oil are working on organic amendments against root- seeds. Seeds are an essential source of nourishment for knot nematodes, such as animal manures, composts, humans and include approximately 25–30% protein, agricultural wastes, crop residues, and plant derivatives 45–50% oil, 20% carbohydrate, and 5% fiber and slag (Peiris et al., 2020). Very high application rates (50 (Ahmad and Rahim, 2007). Furthermore, peanut –100%) of compost in pots decreased the number cake and green leaves are used as organic manure of juveniles ( J2s) in the soil and roots as well as the and animal feed (Shah et al., 2012). Peanut is one of number of galls of root-knot nematodes, (Mostafa et the most widely consumed and exported oil crops in al., 2022). Egypt. According to FAOSTAT (2022) estimates, the cultivated area in Egypt is approximately 170,000 According to Stirling (2017), the use of amendments feddans, and the total productivity is 293 thousand with high phenolic contents could increase plant tons of peanut pods. resistance to nematodes and hence reduce nematode population levels. Amendments can increase nutrient One of the greatest barriers to the production of peanut and water availability, which benefits plant health crops is plant-parasitic nematodes, which are among and yield, regardless of their effects on nematodes the most destructive infections affecting peanuts (Al-Hendy et al., 2021). Compost and manure worldwide. Numerous types of pathogenic root-knot amendments increased yields by an average of 27% nematodes significantly reduce peanut yields every in field research involving potatoes but did not year (Starr et al., 2002). The root-knot nematode decrease the number of plant-parasitic nematodes Meloidogyne arenaria is the most prevalent species (Kimpinski et al., 2003). These examples of enhanced affecting peanuts globally (Ballén-Taborda et al., plant tolerance from amendments appear to meet 2019). In heavily infested crops, M. arenaria infection the scenario of high efficiency for host production resulted in significant yield reductions. The amount but inefficiency for nematode control, which was of peanut yield loss caused by worm pathogens varies articulated by Melakeberhan (2006) concerning host according to the environment, nematode population productivity. The overproduction of reactive oxygen density, and plant cultivar. It varies from 20 to 90% in species (ROS), such as superoxide anions (O2-) and Egypt (Mokbel, 2014). hydrogen peroxide (H2O2), in response to pathogen attack is a primary and prompt response in plants. Nematicides are detrimental to the beneficial flora This leads to a hypersensitive response, which is and fauna in the soil, even though they are typically typified by cell death at the infection site. Systemic advised for managing nematodes. Furthermore, the acquired resistance (SAR), which ensures long-lasting application of nematicides has an impact on the systemic immunity against both the main pathogen environment (Khan et al., 2019). Thus, alternative that triggers the response and subsequent infection by methods for controlling RKNs, Meloidogyne spp., are other pathogens, typically develops in the challenged urgently needed. plant after a hypersensitive response (Grant and Lamb, 2006). In plant tissues, the synchronization of Abd-Elgawad (2024) highlighted that stakeholders ROS formation and scavenging is crucial because an are seeking more sustainable and efficient alternatives excess of ROS can lead to irreversible cellular damage with minimal impact on the environment and human (Halliwell, 2006). Numerous enzymes have been health to address rising food demand, the challenges linked to plants developing induced resistance to plant of climate change, and the harmful use of toxic diseases (Ojaghian et al., 2014). These enzymes include nematicides. One alternative method of managing peroxidases, catalases, phenylalanine ammonia-lyases, nematodes is to introduce soil organic amendments chitinases, and β-1,3-glucanases. β-1,3-glucanase to the soil. Animal manures and biochar are examples and chitinase can breakdown pathogen cell walls of organic amendments for the control of root-knot and eggshells of nematodes, releasing chemicals that December 2024 | Volume 42 | Issue 2 | Page 147  Pakistan Journal of Nematology function as elicitors in the early phases of phytoalexin were identified on the basis of the morphology of and phenolic compound resistance induction (Silva adult and larval forms (Golden, 1971). Adult females et al., 2004). According to Kurabachew and Wydra of root-knot nematodes (Meloidogyne spp.) were (2014), peroxidase is generally essential for the growth removed from the infected roots whenever they were and development of plants and is closely linked to found, and the perennial pattern of these females was defense mechanisms against infections. Additionally, removed and prepared for examination as described phenolic chemicals play a major role in helping plants by Hunt and Handoo (2009). Meloidogyne species withstand a wide range of pests and illnesses. Higher were identified on the basis of the morphological baseline and/or induced levels of phenolic compounds features of the perennial pattern (Hunt and Handoo, have been found to correlate with nematode resistance 2009). across a wide range of plant‒nematode combinations (Dhakshinamoorthy et al., 2014). This study aimed Nematode communities were analyzed on the basis to determine the frequency and occurrence of of frequency of occurrence (FO %) and population plant-parasitic nematodes associated with peanuts density (PD) (Norton, 1979), where frequency of in fields in the Ismailia governorate. In addition occurrence (FO %) = number of samples containing to, (1) Determine the frequency and occurrence of a genus/total number of collected samples × 100. plant-parasitic nematodes associated with peanut in Population density (PD) = Total number of individuals Ismailia governorate. (2) Screening different local of a genus/number of samples containing this genus. Egyptian peanut cultivars (Giza 5, Giza 6, Ismailia 1, and Ismailia 2) against the root-knot nematode M. Greenhouse experiments arenaria under greenhouse conditions. (3) Examine Screening test: Greenhouse experiments were carried the ability of certain organic amendments to increase out at Ismailia Agricultural Research Station, Egypt, plant resistance and control nematode infection in to assess the response of the growth of four peanut susceptible cultivar. (4) Investigate some growth and cultivars to the root-knot nematode Meloidogyne biochemical parameters in treated and untreated arenaria during the summer season of 2022. plants. Tested cultivars: The reactions of four peanut cultivars Materials and Methods (Giza 5, Giza 6, Ismailia 1, and Ismailia 2) to M. arenaria were evaluated under greenhouse conditions. Survey study The cultivar seeds were obtained from the Field Crop During the August 2021-August 2022 season, 80 Research Institute, Agricultural Research Centre, rhizosphere soil samples were collected from four Ministry of Agriculture, Giza, Egypt. The seeds were different peanut localities (Abu Suwer, Ismailia, surface sterilized before being sown into 25 cm- Kasaseen and Tell El-Kebir) in Ismailia governorate, diameter pots filled with steam-sterilized sandy clay northeastern Egypt. Samples were collected at the soil at a 1:4 ratio. One week after germination, one early vegetative growth, blooming, and premature seedling per pot was thinned. Each seedling (two- stages. The samples were placed in plastic bags, weeks old) was inoculated with approximately 3000 tagged, and brought to our laboratory, where they newly hatched juveniles ( J2s) of M. arenaria obtained were kept in a refrigerator at 5 degrees Celsius until from pure cultures maintained and propagated on processing. Nematode extraction and identification tomato cv. 888. Each inoculated cultivar was replicated were performed. four times. Treatments in which no nematodes were added serve as controls (check plants). The plants were The soil samples were well mixed, and a 250 g watered and fertilized with water-soluble N-P-K subsample from each sample was extracted for (20-20-20) as needed. A randomized complete nematode extraction via the sieving and decanting block design was used to arrange the treatments. The procedure described by Christie and Perry (1951). experiment was terminated 90 days after inoculation, Root samples with disease symptoms were chopped and plant growth and nematode assessment data were into small pieces and incubated for 2‒3 days at room collected. temperature in Petri dishes with distilled water to extract any migratory endoparasitic nematodes The shoot, root fresh and dry weights (g), shoot, root (Young, 1954). Nematode genera and/or species lengths (cm), pod weights (g), number of pods per December 2024 | Volume 42 | Issue 2 | Page 148  Pakistan Journal of Nematology plant, and number of nodules per root system were approximately 3000 newly hatched juveniles ( J2s) of recorded. M. arenaria. Each treatments replicated four times.The experiment was terminated 90 days after inoculation, Nematode assessment: Plants of each cultivar and plant growth and nematode assessment data were were uprooted, and the roots were washed with a collected as described previously. gentle stream of water. The nematode galls were subsequently rated on a 1-9 scale of the gall index Biochemical determinations (GI), gall size (GS), and percent gall area (GA) The enzyme extract was prepared according to according to (Sharma et al., 1994). The damage index Urbanek et al. (1991) to estimate peroxidase and (DI) is calculated by dividing the sum of the GI, GS, catalase activity in fresh leaves. The catalase (CAT, and GA by 3 (Sharma et al., 1994). On the basis of EC 1.11.1.6) and peroxidase (POD, EC 1.11.1.7) DI, the host susceptibility (designation of resistance) activities were estimated according to Urbanek et al. of each plant cultivar is determined according to the (1991). The unit of CAT activity was defined as the following scheme: plants with DI = 1 are designated amount of enzyme that decomposes 1 mM H2O2 highly resistant; DI= 2 to 3, resistant; DI= 4 to 5, per mg-1 protein.min. POD activity was expressed as moderately resistant; DI = 6 to 7, susceptible; DI = the change in absorbance every 0.5 min at 425 nm 8 to 9, highly susceptible (Sharma et al., 1994). The using a spectrophotometer. Phenylalanine ammonia- number of egg masses/root systems as well as the lyase (PAL, EC 4.3.1.1) activity was determined number of second-stage juveniles in each pot were spectrophotometrically at an absorbance of 290 nm recorded (Goodey, 1963). (Sadasivam and Manickam, 1996). Chitinase (EC 3.2.1.14) and β-1,3-glucanase (EC 3.2.1.39) activities Organic soil amendment treatments were determined according to the methods of Wirth Three organic soil amendments (cattle manure, and Wolf, (1992). The total phenolic content (mg g-1 compost, and fulvic acid) were obtained as pure FW) was estimated via a modified Folin–Ciocalteu sterilized dry powders from the local market, and a method (Horwitz et al., 1970). chemical analysis was performed (Table 1). All the materials were applied alone or in combination for Statistical analysis efficacy in managing M. arenaria on peanuts. All the All the statistical analyses were carried out via the tested materials were incorporated uniformly 7 days computer software Statistical Package for Social before being planting into the top of the soil pots. Science SPSS (IBM-SPSS ver. 29.0) (Knapp, 2017). Seeds of the peanut cultivar Giza 6 were sown with Data were checked for normality using Shapiro- three seeds per pot and thinned to one at one week Wilk and Kolmogorov Smirnov, to check whether after planting. There were eight treatments in four data parametric or nonparametric, Accordingly, replicates arranged in a randomized complete block parametric data analysis were applied. The difference design. The treatments included the following: (1) between infected and control plants for were checked cattle manure applied at 2 tons/ feddan; (2) compost statistically. In addition, the difference between tested applied at 2tons/ feddan; (3) fulvic acid applied cultivars was also checked using one way ANOVA. at 50kg/ feddan; (4) cattle manure + compost; (5) The data are presented as the means and standard cattle manure + fulvic acid; (6) compost + fulvic deviations, followed by the least significant difference acid; (7) fosthiazate (Nemathorin®) 10% G applied (LSD) test and Duncan’s multiple range test (DMRT) at 12.5k/ feddan; and (8) control (nematode only). at the 0.05 level. Each seedling (two-weeks old) was inoculated with Table 1: Chemical analysis of the cattle manure and compost used in the experiments. Value Organic pH* E.C Organic Total C/N Total phos- Total matter (%) (dS m -1) ** carbon% nitrogen (%) ratio*** phorus (%) potassium (%) Cattle manure 29.00 7.30 4.12 19.00 0.97 19.6:1 0.61 0.58 Compost 25.20 7.10 4. 20 18.90 0.91 20.7:1 0.39 0.44 * pH = (Negative logarthim hydrogen ion). **Electrical Conductivity, (ds m ) (decisiemens per meter) *** C/N ratio = total carbon (%)/total -1 nitrogen (%) (dimensionless). December 2024 | Volume 42 | Issue 2 | Page 149  Pakistan Journal of Nematology Results and Discussion presented the greatest value, followed by Giza 5. Survey study Table 2: Population density (PD) and frequency of The data presented in Figure 1 and Table 2 indicate occurrence (FO%) of plant-parasitic nematode genera the presence of seven phytoparasitic nematode genera associated with peanuts in Ismailia Governorate during in the soil samples of the surveyed peanut fields of the 2021-2022 growing seasons. the Ismailia governorates. Most of the surveyed Nematode genera Population Frequency of peanut fields had populations of more than 420 density (PD)1 occurrence (FO%)2 Meloidogyne spp., which is the main pest of this crop Helicotylenchus 80 23 per 250 g of soil. The percentage of occurrence in Longidorus 40 5 the surveyed samples was 88%. The identification of Meloidogyne 420 88 Meloidogyne spp. indicated that M. arenaria (60%) Pratylenchus 40 5 was the dominant species in all the peanut root Rotylenchulus 40 4 samples collected from the samples, followed by M. Tylenchorhynchus 220 25 Xiphinema 20 4 javanica (40%). The second most widely distributed 1 Population density (PD) = number of nematodes per 250 g of soil genus was the stunt nematode Tylenchorhynchus spp., for a genus and/or species/number of samples containing this genus with a population density of 220 per 250 g of soil and/or species. 2Frequency of occurrence (FO %) = (number of samples and a frequency of occurrence of 25%. The third most containing a genus and/or species/total samples collected) × 100. common genus in the surveyed samples was spiral nematodes Helicotylenchus spp., with an occurrence of 23% and a population density of 80 per 250 g of soil. (A) Density (B) Frequency Xiphinema e e Tylenchorhynchus b b Rotylenchulus d d Pratylenchus de de Meloidogyne a a Longidorus d d Helicotylenchus c c 0 100 200 300 400 500 0 20 40 60 80 100 Figure 1: (A) Population density and (B) frequency of occurrence (%) of plant-parasitic nematode genera associated with peanuts in Ismailia Governorate during the 2021-2022 growing seasons. Bars followed by different values are significantly different according to the DMRT. Figure 2: Shoot length, root length, shoot fresh weight, Susceptibility of the tested cultivars to M. arenaria root fresh weight, shoot dry weight and root dry weight Based on the damage index (DI) displayed in Table 3, of different peanut cultivars (Giza 5, Giza 6, Ismailia the susceptibility/resistance of four different peanut 1 and Ismailia 2) infected with Meloidogyne arenaria. cultivars to the root-knot nematode M. arenaria was Bars with different letters are significantly different categorized. According to the data, the cultivars were according to the DMRT. divided into two groups: susceptible (Ismailia 1 and Ismailia 2) and highly susceptible (Giza 6 and Giza The growth and yield parameters of the peanut 5). The cultivar Giza 6 has a damage index (DI) of cultivars (Giza-5, Giza-6, Ismailia-1 and Ismailia-2) 8.90, whereas the cultivar Giza 5 has a DI of 8.00. were severely negatively impacted by the root-knot The number of second-stage juveniles ( J2s) in 250 g of nematode M. arenaria (Figures 2 and 3). Nematode soil and the egg mass index (EI) varied significantly, infection caused significant reductions in the fresh as revealed by one-way ANOVA (p≤0.05), between shoot weights, fresh root weights, dry shoot weights, the peanut cultivars. In general, Ismailia 2 presented dry root weights, shoot and root lengths, as well as the lowest egg mass/root and EI, whereas Giza 6 the weight and number of pods and the number of December 2024 | Volume 42 | Issue 2 | Page 150  Pakistan Journal of Nematology nodules/plant for all cultivars. When the infected peanut cultivars were compared with the control plants, notable significant differences in plant growth and yield parameters were detected, as revealed by one- way ANOVA (p≤0.05). The shoot length, shoot fresh weight, shoot dry weight, root fresh weight and root dry weight of Giza 6 decreased the most among all the examined cultivars with nematode infection. The percentages of the reduction in shoot length, shoot fresh weight (SFW), shoot dry weight (SDW), shoot fresh weight (RFW), and root dry weight (RDW) were 29.0, 25.0, 58.0, 62.0, and 63.0%, respectively. Furthermore, the greatest decreases in pod weight and the number of pods and nodules per plant also Figure 3: Number of pods per plant, pod weight and resulted in 49.0%, 32.0%, and 56.0% decreases in Giza number of nodules per plant of different peanut cultivars 6, respectively. According to the results in Figures 2 (Giza 5, Giza 6, Ismailia 1 and Ismailia 2) infected with and 3, the cultivar Giza 6 was the most damaged, Meloidogyne arenaria. Bars with different letters are whereas the cultivar least affected was cv. Ismailia 2. significantly different according to the DMRT. Table 3: Susceptibility of peanut cultivars to root-knot nematode, Meloidogyne arenaria infection. Cultivars No. of Gall index Gall size Gall area Damage Host susceptibili- No. of No. of egg Egg mass galls/root (GI) (GS) (GA) index (DI) ty/ Resistance J2s/250 g soil masses/root index (EI) Giza 5 132.50b 9.00a 7.50b 7.50b 8.00b HS 290.00b 29.00b 5.20b Giza 6 233.00a 9.00a 8.70a 9.00a 8.90a HS 460.00a 50.00a 6.20a Ismailia 1 93.20c 8.00b 7.00bc 7.50b 7.40b S 210.00c 27.70b 5.20b Ismailia 2 85.00c 8.00b 6.00c 6.50b 6.80c S 170.00d 19.50c 4.20c LSD 0.05 14.72 1.23 1.31 34.40 4.62 p value 0.000* 0.003* 0.012* 0.000* 0.000* f-ratio 202.23 8.10 5.67 131.93 73.85 The data are the average of 4 replicates. Different letters indicate significant differences among treatments within the same column according to Duncan’s multiple range test (P ≤ 0.05). GI and EI indices, 1 = no galls, 2 = 1-5 galls, 3 = 6-10 galls, 4 = 11-20 galls, 5 = 21-30 galls, 6 = 31-50 galls, 7 = 51-70 galls, 8 = 71-100 galls, and 9 = > 100 galls. HS (highly susceptible host), and S (susceptible host). Table 4: Efficacy of organic soil amendments on root-galling, egg mass and final nematode population of Meloidogyne arenaria on peanut plants under greenhouse conditions. Treatment No. of galls/ root Red. % No. of egg masses/ Red. % No. of J2s/250 g soil Red. % system root system Control (Nematode only) 198.00a - 53.00a - 456.00a - Cattle manure 36.30 de 81.60 20.00 cd 62.00 113.00 d 75.00 Compost 45.60 c 76.90 25.30 b 52.00 130.00 d 71.40 Fulvic acid 55.00 b 72.00 26.00 b 51.00 193.00 b 57.60 Cattle manure + compost 32.00e 83.80 15.00e 71.60 86.00e 81.00 Cattle manure + fulvic acid 40.60 cd 79.00 19.00 de 64.00 133.00 d 71.00 Compost + fulvic acid 53.00 b 73.00 24.30 bc 54.00 166.00 c 63.00 Fosthiazate 10G 20.00 f 90.00 9.00 f 83.00 40.00f 91.00 LSD 0.05 6.00 4.40 24.40 One way ANOVA p value 0.000* 0.000* 0.000* f-ratio 803.93 75.97 241.14 The data are the average of 4 replicates. Different letters indicate significant differences among treatments within the same column according to Duncan’s multiple range test (p≤ 0.05). Red.%= percentage of reduction =(Cp-Ip/Cp)Х 100. December 2024 | Volume 42 | Issue 2 | Page 151  Pakistan Journal of Nematology Efficacy of organic amendments for the management of significantly greater in the treatment groups than in M. arenaria the control group, which presented the lowest values. The data presented in Table 4 revealed that all the The combination treatment (cattle manure + compost) treatments significantly reduced the number of galls, and fosthiazate 10G resulted in the greatest increase egg masses/roots and final nematode population in shoot fresh weight (41.3 and 43.6 g, respectively), ( J2s) in soil to different degrees. The final nematode followed by the cattle manure treatment (38 g). population in 250 g of soil and several galls and egg masses/roots are presented in Table 4. The nematicide fosthiazate 10G achieved the greatest reduction in the number of galls (90.0%), number of egg masses (83%), and final nematode population (91.0%). However, the combination of cattle manure with compost induced a reduction in the number of galls (83.8%), the number of egg masses (71.6%), and the final nematode population ( J2s) (81.0%). Moreover, a lesser effect was observed with fulvic acid, which caused a reduction in the previous criterion values of 72.0, 51.0, and 57.6% respectively (Figure 4). Figure 5: Plant growth parameters of peanuts infected with Meloidogyne arenaria in different treatment groups, including cattle manure, compost, fulvic acid, cattle manure + compost, cattle manure + fulvic acid, compost+ fulvic acid, control (nematode only) and nematicide (fosthiazate 10G) treatments. Bars with different letters are significantly different according to DMRT. The root fresh weight (g/plant) was greater in all the Figure 4: Numbers of galls, egg masses/root system, and groups than in the control group, which presented the final nematode populations ( J2s) in different organic lowest values. Compared with the control treatment amendment treatment groups in peanuts infected with (8.0 g), the treatments with cattle manure + compost Meloidogyne arenaria. Bars with different letters are and fosthiazate 10G significantly increased the fresh significantly different according to DMRT. weight of the roots (14.0 g) (Figure 5). Effects of organic amendments on several peanut growth The average pod weight (g) per plant (Figure 5) parameters significantly differed between the treatment groups. The shoot fresh weight (g/plant) of the plants in the Pod weights were greater in all the groups than in treatment groups was significantly different among the control group. The maximum pod weight was the cattle manure, compost, fulvic acid, (cattle manure recorded in the fosthiazate 10G treatment (20 g), + compost), (cattle manure + fulvic acid), (compost + followed by the combined treatment (cattle manure fulvic acid), control (nematode only) and nematicide + compost) (19.3 g), with a nonsignificant difference (fosthiazate 10G) groups, as revealed by one-way compared with the control treatment (7.6 g). ANOVA (p