Egg Mass Index Research Articles

Evaluation of F1 hybrids against root knot nematode (<i>Meloidogyne incognita</i>) resistance in Brinjal (<i>Solanum melongena</i> L.)

Brinjal is one of the most important commercial solanaceous vegetable crops. Root knot nematodes cause severe yield losses in brinjal both in open and poly house conditions. Host plant resistance is considered to be a viable solution and cost-effective method to manage the root knot nematodes. Ten genotypes along with their nineteen F1 hybrids were screened for resistance to root knot nematode and biochemical basis of resistance was assessed. Two F1 hybrids viz., IIHR-824 x VI046101, IIHR-824 x IIHR-766, parents viz., IIHR-824 and VI046103 were found to be resistance to M. incognita with gall index/ egg mass index of 1. Three F1 hybrids, IIHR-824 x IIHR-356, IIHR-824 x IIHR-835, VI046103 x IIHR-834 showed moderately resistant reaction. The root biochemical compounds analysis indicated that, total phenolic content (67.05 mg/g) and flavonoids (121.32 mg/g) were found higher in the inoculated roots of resistant line i.e. IIHR-824 indicating their role in conferring resistance. The identified F1 hybrids having resistance can be explored for commercial cultivation.

Incidence of Root-Knot Nematode on Misai Kucing (Orthosiphon stamineus) in Peninsular Malaysia: A New Discovery

A survey was conducted over one and half years to estimate the occurrence of root-knot nematode infestation on Ortosiphon stamineus (misai kucing) in selected locations around Peninsular Malaysia. Infestations were monitored in ten misai kucing plantation areas in Pulau Pinang, Perak, Negeri Sembilan, Selangor, Johor, Terengganu, and Kelantan. The survey indicated that misai kucing grown on sandy clay-type soil tends to be more susceptible to heavy root-knot nematode infestation. The highest frequency of disease incidence in which almost all the roots of misaim kucing have a knot-like appearance (100%) was reported from the Batu Kurau area. The other two locations, Ipoh and Pantai Baru, had mild infestations, and these were reported as 16% and 4% incidence. The methodology for access the damage caused by the root-knot nematodes in misai kucing, Meloidogyne gall index and its egg-mass index were calculated and these were found in the range of 1-4. The average egg mass from ten randomly selected stunted misai kucing plants from Batu Kurau was recorded as 599.4, with the highest number of 2274 egg mass per plant. Sampled plants showed the significant presence of Meloidogyne incognita. The root-knot nematodes were morphologically identified based on the perineal patterns of females and the head morphology of both Meloidogyne females and males.

Reaction of Brazilian genotypes of pulses (pea, chickpea and lentil) to the root-knot nematode Meloidogyne enterolobii

Summary The root-knot nematode, Meloidogyne enterolobii, is an important pathogen of numerous crops, including the so-called pulses. Hence, it is necessary to identify genetic resistance, as it is the most efficient, cost-effective, and environmentally sound way to manage nematodes in the field. The objective of this study was to screen a Brazilian germplasm collection of pulse crops (peas, chickpeas, and lentils) comprising accessions from the Embrapa Germplasm Bank and commercial cultivars against M. enterolobii under glasshouse conditions. The experiment was conducted with 23 treatments (genotypes), i.e., 14 pea, six chickpea and one lentil genotype, and two tomato cultivars, ‘Rutgers’ (susceptible) and ‘Nemadoro’ (resistant). Each plant (replication) was inoculated with 5000 eggs and second-stage juveniles (J2) of M. enterolobii and evaluated 65 days after inoculation, considering the following variables: gall index, egg mass index, number of eggs per g of roots, and reproduction factor. The experiments were conducted at two independent time points (summer and autumn/winter). Results showed that all 23 plant genotypes were susceptible to the nematode, with pea genotype ‘Itapuã’ being intolerant to infection. Cultivation of pulse crops has been steadily increasing both in Brazil and worldwide. Our research findings make a valuable contribution to the ongoing efforts to identify genetic resistance to nematode pathogens that can significantly affect the productivity of these crops. By identifying and developing resistant genotypes, pulse crop yields can be safeguarded, and sustainable agricultural practices can be supported.

Biological control of root-knot nematodes in common beans using putative nematocidal species of Trichoderma indigenous to Pakistan

ABSTRACT The putative nematocidal strains of Trichoderma for controlling root-knot nematodes were isolated from different agricultural fields in Pakistan. The Trichoderma isolates were confirmed using morphological and molecular characterisation. The root-knot nematodes were isolated from infected common bean plants Phaseolus vulgaris and identified as Meloidogyne incognita through phenotypic characteristics. Both in vitro and in vivo assays were performed. The nematocidal activity of the selected Trichoderma spp. was assessed using culture filtrate and spore suspension assays. Parameters including J2 mortality, egg hatching inhibition, root gall index, and egg mass index were calculated. The culture filtrates of T. bevicrassum strain ISO-03 caused significantly higher J2 mortality (71%) and inhibited egg hatching (68%) as compared to the activities of culture filtrates of the other two strains used in this study. The least control activity was observed in case of the culture filtrates of T. viride strain ISO-05 with 21% J2 mortality and 19% egg hatching inhibition. Similarly, the spore suspensions of T. brevicrassum ISO-03 showed the highest mortality of M. incognita juveniles (64% with respect to control) as well as the egg-hatching inhibition rates of 59%. In the in vivo study, the same strain T. bevicrassum ISO-03 significantly reduced the root galling index and egg mass indices as compared to the control. Furthermore, T. bevicrassum ISO-03 significantly promoted plant growth compared to the control. Overall, T. bevicrassum ISO-03 was identified as a potent biocontrol strain against root-knot nematodes in addition to its plant growth-promoting characteristics.

Impact of Cucurbita moschata Resistant Rootstocks on Cucumis sativus Fruit and Meloidogyne incognita Development.

Plant grafting can provide resistance to nematodes. There is a distinct need to determine the role of Meloidogyne incognita-resistant rootstocks on the growth and quality of grafted cucumber plants. Cucumber (Cucumis sativus L.) cultivar Jinchun No. 4 (J) was hole grafted onto the pumpkin (Cucurbita moschata) cultivars Xiuli (X), Banzhen No. 3 (B), and its root to generate JX, JB, and JJ plants. The histopathology and M. incognita development associated with JX, JB, and JJ were analyzed under incubator and high plastic tunnel conditions. Under incubator conditions, M. incognita root galls and egg mass indices associated with the JX and JB resistant rootstocks were significantly (P < 0.05) lower than those associated with JJ susceptible rootstocks. In addition, the number of eggs were 73.3 ± 8.8% and 85.3 ± 7.7% less, respectively. The number of second-stage juveniles (J2s) in JX roots decreased by 57.1 ± 9.2% compared with that in JJ, and the giant cell and J2 development were poor in JX and JB roots. In pot experiments under a high plastic tunnel, plant height, stem diameter, leaf area, and yield of M. incognita-infected JX plants were not significantly different from those of noninoculated control. There was no significant difference in fruit weight, length, firmness, soluble solids, and color among the three grafted plants. The yield per JB plant was increased compared with that of JJ, irrespective of nematode presence. In the M. incognita-infested soil experiment in a high plastic tunnel, the yield per JX and JB plant were significantly higher than JJ (P < 0.05). Thus, the pumpkin rootstock Xiuli and Banzhen No. 3 are promising rootstocks for managing M. incognita without affecting cucumber fruit quality. Grafting provides a good basis for studying the defense mechanism of rootstocks against M. incognita.

Reaction of soybean cultivars to two races of Meloidogyne enterolobii and their aggressiveness under plastic house conditions

Summary Limited information is available regarding the susceptibility or resistance of soybean cultivars to Meloidogyne enterolobii. Recently, a new race of this species was detected in Brazil parasitising cotton and soybean. This nematode has the potential to pose a problem in both of these crops, since it is pathogenic and virulent to several economically important plants that have resistance genes to other Meloidogyne species. The aim of this study was to assess the responses of EMBRAPA’s main soybean cultivars with confirmed resistance to M. incognita and M. javanica to the two races of M. enterolobii detected in Brazil. Additionally, this study aimed to characterise the aggressiveness of these nematode races. The experiments were conducted in a plastic house, in a factorial scheme with 16 soybean cultivars × two M. enterolobii races (guava and cotton), totalling 32 treatments × eight replications, and evaluated with two replications over time. Soybean sowing took place in pots containing 1.7 l of a mixture of soil, sand and Bioplant® substrate (1:1:1), previously autoclaved. Each soybean plant was inoculated with 5000 eggs of M. enterolobii. After 75 days for the first experiment, and 90 days for the second, the following variables were evaluated: gall index (GI), egg mass index (EMI), total number of eggs per g root (NEGR) and the reproduction factor (RF). Both races of M. enterolobii showed reproductive ability in all soybean genotypes (with or without known genetic resistance), albeit with moderate to low values in comparison to their reproduction on tomato plants. The race from cotton was considered statistically more aggressive than the guava population on soybean cultivars. Only ‘BRS 7180 IPRO’ was moderately resistant to both races in both experiments. In view of the importance and prospects for expansion of the soybean crop, the findings of this study contribute to a better understanding of the resistance and aggressiveness exhibited by the two races of M. enterolobii, Moreover, the study highlights the significant challenge that lies ahead in developing breeding programmes to select soybean genotypes with multiple resistance to Meloidogyne spp.

Assessment of digestible amino acid requirement in White leghorn Layers based on production performance at low protein levels in diet

To understand the optimal requirement of d.lysine and threonine in White Leghorn (WL) layers (25-44 weeks), two independent experiments were executed. For the d. lysine study, birds (N=528) were categorized into eleven dietary groups (11×6×8) and were fed with two different protein levels (13.36 and 15.78%) each containing five concentrations of d. Lys. To optimize d. Thr, layers (N=390) were allotted to thirteen groups (13×5×6) in these diets were formulated by fixing the lysine concentrations at 0.65 and 0.60% with 13.36 and 15.78% protein levels respectively. Threonine was supplemented in both diets at graded levels of lysine. Basal diets with 0.70% lysine and 17% protein; threonine at 66% lysine served as corresponding controls. Egg production response to supplemental d. Lys was quadratic. Net feed efficiency and egg mass indices response were in both linear and quadratic. Supplementation of diets with Thr, the response of egg production was linear whereas, it was both linear and quadratic for economic parameters. In conclusion, supplementation of d. Lys at 0.65 and 0.60%; 69 and 72% d. Thr as % of d. Lys at low and high protein diets is optimal for better egg production with economic efficiency in WL layers in the tropics.

Control of Fusarium oxysporum f. sp. radicis lycopersici Jarvis &amp; Shoemaker (Ascomycota: Hypocreales) and Meloidogyne incognita (Kofoid &amp; White, 1919) Chitwood, 1949 (Nemata: Meloidogynidae) with Aspergillus niger Tiegh. (Ascomycota: Eurotiales) culture filtrate on tomato

The effects of Aspergillus niger Tiegh. (Ascomycota: Eurotiales) culture filtrate on Meloidogyne incognita (Kofoid &amp;amp; White, 1919) Chitwood, 1949 (N) and Fusarium oxysporum f. sp. radicis lycopersici Jarvis &amp;amp; Shoemaker (Ascomycota: Hypocreales) (FORL) were investigated under controlled conditions on tomato between April and August 2022 in the Isparta province. The study consisted of 8 treatments; 1: N, 2: FORL, 3: N+A. niger, 4: FORL+A. niger, 5: N+FORL, 6: N+FORL+A. niger, 7: N+FORL+nematicide, 8: N+FORL+fungicide. In inoculation, 1000 M. incognita second juvenile larvae/1ml and 3X106 spore/ml FORL were used for each seedling according to treatment. Two days after inoculation, 10 ml of undiluted A. niger culture filtrate was applied to each potting soil. After 60 days, 0-9 gall and egg mass index, and 0-4 disease severity scale were evaluated. While the suppressive effect of A. niger culture filtrate on the gall and egg mass of M. incognita was found over 55%, disease severity was found to be over 25%. The highest suppressive effect on gall and egg mass was determined in N+FORL+nematicide, followed by N+FORL+A. niger. The disease severity of N+FORL+A. niger, N+FORL+nematicide, and N+FORL+fungicide has been determined to be lower than N+FORL and FORL.

Domateste Kök Ur Nematodu Mücadelesinde Kitosanın Toprak ve Yaprak Uygulamaları

In this research, the effect of soil, foliar and simultaneous soil+foliar applications of chitosan on gall and egg mass of root-knot nematode Meloidogyne incognita was investigated in tomato plants under controlled conditions (24±1°C, 60±5% RH). Fluopyram (0.16 ml/L) was used as positive control while only nematode-treated plants were considered as negative control. The study was set up in a randomized plot design with 5 replications for each application. The liquid suspension of chitosan diluted at 1% was used. In soil application, 5 ml was applied to each pot by using a graduated cylinder while in foliar application, the liquid suspension at 1% was applied using a portable hand sprayer until the solution was finished. The study was evaluated according to the 1-9 gall and egg mass index 60 days after inoculation of nematodes. The lowest gall (2.8) and egg mass (2.4) indexes were detected in the simultaneous soil+foliar application and took place in the same statistical group with the positive control nematicide. It was determined that the nematicidal effect of chitosan has increased in the case of combined soil and foliar applications. These results support the fact that chitosan applications are successful in the control of root-knot nematode.

Impact of maize particle size on egg production and egg quality of White Leghorns in early stage of production

The aim of the present study was to determine the effect of the maize particle size on the performance of layers. Five maize-soybean based diets were formulated with maize particle size of 4.0, 6.0, 8.0, 10.0 and 12.0 mm sieve size with five treatments (T1: 4.0 mm mash diet; T2: 6.0 mm mash diet; T3: 8.0 mm mash diet; T4: 10.0 mm mash diet; T5: 12.0 mm mash diet) fed from 20 to 28 weeks of age. Each treatment was replicated three times, with 10 birds in each replicate. The results showed no significant difference in average daily feed intake, live weight, hen day egg production percentage, egg mass and egg indices except for haugh unit, which was highest for the 4 mm screen size and lowest for the 12 mm screen size in layers from 20 to 28 weeks of age. FCR (g/g egg mass) was highest for T3 as compared to the average of other treatments not affected by either of the feeds. In conclusion, the size of the screen used to mill the grain had no impact on hen production within the range of the study. Furthermore, the decision to grind grains more coarsely than is already customary would be favourable for the environment and the economy because it would reduce the amount of energy, labour, and time utilised in feed mills.

Control of Meloidogyne javanica in cowpea with silicon application

Cowpea (Vigna unguiculata (L) Walp) can suffer significant losses due to the attack of Meloidogyne javanica. The most effective control is through nematicides, however, it is an expensive treatment, so alternative measures have been sought. Therefore, the objective was to evaluate the effect of silicon on the control of M. javanica in cowpea plants. The experiment was carried out in a greenhouse, in a completely randomized design, in a 5 × 2 + 1 factorial scheme, being: five doses of Si (0, 60, 120, 180, and 240 mg dm-3), two soluble sources of Si (Quimifol Silício® and sodium silicate P.A.), plus an additional treatment consisting of tomato cultivation in soil without the addition of Si and with nematodes, with four replications. Sixty days after inoculation in the plants, the root systems were collected and evaluated: volume, length and fresh mass of roots, gall index, egg mass index, reproduction factor, reproduction index, and reduction of reproductive factor of M. javanica. The sources of silicon at different doses had a positive effect on root variables. They were also able to reduce the parasitism variables of M. javanica in cowpea plants.

Ajuste de níveis de inóculo para avaliação da resistência de genótipos de cenoura a Meloidogyne incognita

ABSTRACT One of the main phytopathogens that cause enormous economic losses in several agricultural species, including carrots, are the root-knot nematodes belonging to the genus Meloidogyne. Thus, in order to identify the best population level for inoculum of the root-knot nematode (Meloidogyne incognita) for maximum expression of symptoms of this nematode attack on carrots, an experiment was carried out to evaluate the carrot cultivar Brasília (CBR) and the population Pop-750 (CRO). The experiment was carried out in a greenhouse at Embrapa Vegetable, Brasília-DF, in 5 L pots, with six replications, in a 4x2 factorial scheme in a completely randomized design, in the dosages of 0, 1, 5 and 10 thousand eggs and occasional juveniles of 2nd stage (E+J2R). ‘Rutgers’ susceptible tomato cultivar was used as control to verify inoculum efficiency. Inoculation was carried out 30 days after sowing and evaluation 60 days after inoculation. Gall index (GI), egg mass index (EMI), number of eggs plus occasional second stage juveniles per gram of root (E+J2R) and reproduction factor (RF) were performed. There were differences between genotypes and between inoculum levels for all variables evaluated. For CRO, inoculum levels of M. incognita from 1,000 E+J2 the plants already manifested symptoms and changes in all evaluated variables, with ideal levels around 5 to 7 thousand E+J2R, above 7 thousand E+J2R nematode multiplication to express symptoms decreased. For CBR the response variables E+J2 at root and RF inoculum levels close to 5 thousand E+J2R also present the best results, but when the characterization is based on the evaluation of GI and EMI, suitable inoculum levels would be close to 9 and 12 thousand E+J2R.

Evaluation of summer and winter cover crops for variations in host suitability for Meloidogyne incognita, M. arenaria and M. javanica

Summary Root-knot nematode (RKN) is an important pathogen on vegetables; therefore, planting a non- or poor host cover crop following a susceptible vegetable crop is a promising management option. This study builds upon previous studies and evaluates the variations in host status of cover crop candidates for reducing the reproduction of RKN populations (Meloidogyne incognita, M. arenaria and M. javanica) in Georgia, USA, to shed light on previous inconsistencies regarding the host status of cover crops and effectiveness in the field. Two glasshouse trials tested the host status of 14 plant species and 18 cultivars plus susceptible tomato ‘Rutgers’. Sixty days after inoculation, roots were evaluated for galling (GI) and egg mass index (EI). Gall formation was not a reliable indication of RKN reproduction for many cover crops, which had higher EI than GI. Based on GI, all cover crops were either non-hosts, ranging from non-hosts to poor hosts or poor hosts to all three RKN species, except blue lupine and hairy vetch, which were susceptible to all three RKN species and had a GI and EI equal to the susceptible tomato control. Based on EI, only bahiagrass, bermudagrass, marigold, millet and velvetbean were either non-hosts or ranged from non-hosts to poor hosts. Eleven cover crops varied in host status to the three RKN species screened, ranging from either non-host to poor hosts or poor hosts to susceptible, which could explain inconsistencies in glasshouse and field trials.

Modulation of the laying performance and biochemical blood parameters of Japanese quails upon dietary Clanis bilineata larvae

AbstractThis study was performed to evaluate the effects of dietary Clanis bilineata larvae (CBL) on laying performance and biochemical blood parameters of Japanese quails. CBL was used to replace 10% corn meal of the basic diet to formulate the treatment feed, while the basic diet without CBL served as control feed. CBL treatment increased egg production, egg weight, egg mass, feed consumption, yolk ratio, shell ratio and egg shape index and serum total protein, albumin, globulin, high‐density lipoprotein cholesterol, low‐density lipoprotein cholesterol, IgG and IgG and decreased feed conversion ratio and albumin ratio of eggs and serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, triglycerides and total cholesterol. The results indicated that CBL could improve laying performance and health status of Japanese quails.

Interactive effect of Meloidogyne incognita and fly ash on the growth, physiology, and antioxidant properties of carrot (Daucus carota L.).

Alternative methods are needed to replace chemical nematicides because they have the potential to damage beneficial soil microbial diversity. Therefore, the present work was done to elucidate the soil ameliorative, plant-growth-promoting, and nematicidal properties of fly ash. A random block-designed pot experiment was conducted during the period, December 2018-February 2019. Seeds of carrot (Daucus carota L.) were sown under natural conditions in clay pots containing a growth medium comprising of field soil amended with different levels of fly ash. Plants were inoculated with Meloidogyne incognita that were molecularly characterized using 18S and D2/D3 fragments of 28S rDNA and morphologically through perineal pattern arrangement. The results revealed that fly ash application improved the soil's important physicochemical characteristics. The inoculation of M. incognita significantly reduced the plant growth, yield, and pigment content of carrot compared to the untreated uninoculated plants. Carrot grown in 15% fly ash (85:15 w/w field soil:fly ash) growth substrate had significantly (P ≤ 0.05) improved plant growth, yield, and pigment content as compared to the untreated inoculated plants. Moreover, the proline content and the activity of superoxide dismutase (SOD) and catalase (CAT) were enhanced by applying 15% fly ash. Fly ash amendment to the soil not only improved plant growth and yield but also reduced the gall index and egg mass index per root system of the carrot as well. Our results, therefore, suggest that 15% fly ash can be used in a sustainable way to improve the growth, yield, and resistance of carrot against the infection of M. incognita.

Identification and resistant characterization of legume sources against Meloidogyne incognita

Root-knot nematodes (RKNs; Meloidogyne spp.) are becoming a serious problem in legume production. This study identified Vigna genotypes exhibiting resistance to M. incognita (RKN) and characterized the modes of the resistance to M. incognita. In total, 279 accessions from 21 Vigna species were screened for resistance based on a galling index (GI) and an egg mass index (EI). Seven accessions were highly resistant to RKN with GI≤25, namely JP74716 (V. mungo var. mungo; cultivated black gram), JP107881 (V. nepalensis), JP229392 (V. radiata var. sublobata; wild mungbean), AusTRCF118141 (V. unguiculata subsp. unguiculata; cultivated cowpea), AusTRCF306385 (V. unguiculata subsp. unguiculata), AusTRCF322090 (V. vexillata var. vexillata; wild zombi pea) and JP235929 (V. vexillata var. vexillata). JP229392 and AusTRCF322090 were the most resistant accessions having EI values of 18.74 and 1.88, respectively. Continuous culture of M. incognita on both JP229392 and AusTRCF322090 resulted in a weakness in pathogenic ability for this RKN. The resistance in JP229392 and AusTRCF322090 to RKN appeared to be antibiosis that was associated with reduced nematode penetration, retardation of nematode development and impeding giant cell formation. The Vigna germplasm resistance to RKN identified in this study could be utilized as gene sources for the development of RKN-resistant Vigna cultivars.

Characterization of lettuce genotypes for resistance to root-knot nematodes (Meloidogyne spp.)

ABSTRACT Genetic resistance is the most suitable mechanism to control root-knot nematodes in lettuce. However, information about the resistance levels of currently used lettuce cultivars is scarce in the literature. Thus, the objective of this research was to characterize lettuce cultivars for resistance to root-knot nematodes Meloidogyne incognita (Mi) and M. javanica (Mj), aiming the identification of resistance sources for breeding, and to transfer information to the productive sector. We evaluated 97 lettuce genotypes in tree trials. In the first one (preliminary assessment), 92 lettuce genotypes were inoculated simultaneously with M. incognita race 1 and M. javanica species, 17 days after sowing. The gall index (GI) was evaluated 41 days after inoculation. In the second trial nine genotypes, selected from the first trial, were evaluated; and in the third trial, two new cultivars from Embrapa were evaluated. In the last two trials, the nematode species were inoculated separately, and the egg mass index (EMI), number of eggs per gram of roots (NEGR) and reproduction factor (RF) were also evaluated. In both trials, the lettuce cultivars Salinas 88 and Grand Rapids were used as resistant controls, as well as cultivar Irene as the susceptible control. The data were submitted to analysis of variance and treatments means grouping by Scott-Knott´s test. The crisp leaf cultivars presented a higher degree of resistance to the root-knot nematodes compared to the smooth leaf type cultivars. Cultivars Vera and Amanda present resistance to M. incognita, and Vanda to M. javanica. ‘Salinas 88’ present resistance mainly to M. javanica; while cultivar Mônica and the Embrapa cultivars BRS Leila and BRS Mediterrânea are resistant to both nematode species.

Improved Resistance to Root-knot Nematode Species in an Advanced Inbred Line of Specialty Pepper (Capsicum annuum)

Bell and chili peppers are important vegetable and spice commodities worldwide. Significant yield reductions have been attributed to damage caused by root-knot nematodes (RKNs; Meloidogyne spp.). This study addresses the need for developing pepper varieties that have high resistance to RKN, which is now of increasing importance due to restrictions on the use of fumigant nematicides. Our goal is to provide a nonchemical alternative to sustain commercial pepper production in Florida, which is a major producer of peppers in the United States. We evaluated ‘UFRJ107(6)A3’, an advanced inbred line developed from a cross between Capsicum annuum L. ‘Jalapeno’ and ‘Round of Hungary’, for resistance against the nematode in comparison with the parental and three other Capsicum cultivars, namely, C. annuum ‘Charleston Belle’, ‘California Wonder’, and C. chinense Jacq. ‘Datil’ in two separate growth chamber experiments. Based on egg mass indices and reproduction factors, ‘UFRJ107(6)A3’ was significantly more resistant to M. incognita compared with the other five cultivars. When tested with five RKN species, ‘UFRJ107(6)A3’ showed comparably high levels of resistance to M. arenaria and M. floridensis as ‘California Wonder’ based on the nematode reproduction factor. In ‘UFRJ107(6)A3’, however, there were no detectable M. arenaria egg masses, and M. incognita reproduction was minimal compared with that of ‘California Wonder’; both cultivars supported the reproduction of M. enterolobii and M. javanica, although the reproduction factors of M. enterolobii were ≈10-fold higher than M. javanica. To characterize the mechanism of high resistance to M. incognita in ‘UFRJ107(6)A3’, we examined the extent to which infective second-stage juveniles (J2s) were able to penetrate its roots in comparison with the susceptible ‘California Wonder’ and ‘Datil’ in two independent experiments; we conducted RKN root penetration assays with a single plant in a pot and two plants in a single-pot choice test using ‘Datil’ and ‘California Wonder’, respectively, as susceptible standards. In both assays, M. incognita J2s were absent in the roots of ‘UFRJ107(6)A3’ 7 days after inoculation but were present in the susceptible cultivars, indicating that resistance has an effect at the root invasion stage. In growth chamber experiments, at constant temperatures of 28 and 30 °C, ‘UFRJ107(6)A3’ exhibited M. incognita resistance superior to its parents and to the standard resistant bell pepper ‘Charleston Belle’, thus offering the potential to enhance specialty pepper production and for use as a nematode-resistant rootstock for commercial bell peppers.

Performance and cost-benefit analysis of Isa Brown layers on different management systems

BackgroundFew literatures exist on the performance and cost implication of birds reared on different management system. The cost benefit analysis of rearing Isa Brown layers on three different management systems was evaluated in a 9 (9)-week feeding trial. One hundred and forty-four (144) points of lay (19 weeks old) Isa-Brown chickens were procured from a reputable farm in Osun state. The birds were placed on three (3) treatments (battery cage, deep litter, and free range) of three (3) replicates and sixteen (16) birds per replicate in a completely randomized design. Birds reared on conventional cages were arranged into three birds per cage unit. Birds on deep litter were kept on wood shavings, in which perches, laying nests, feeders, and drinkers were provided. Hens on free range management system were kept in a large area of land camped using planks and hexagonal wire mesh which was partitioned into various replicates. Sheds were provided for the birds to protect them from harsh weather conditions, and perches, laying nests, feeders, and drinkers were also provided. The birds on all the treatments (battery cage, deep litter and free range) were given the same diet, and the study period lasted for sixty-five days. The weight gain per bird, percentage weight gain, hen day production (HDP), egg mass index, and feed conversion ratio were determined. At the end of the experiment, these records were used to evaluate economic indices.ResultsThe result showed that only the feed intake and total feed intake were significantly (p < 0.05) influenced by management systems in all the parameters measured for performance. The daily feed intake, total feed intake total cost of feed consumed, quantity of egg produced per bird, revenue generated from eggs, production cost, net benefit, cost-benefit ratio, and percentage cost of production were significantly (p < 0.05) influenced by management systems. Birds kept on deep litter system recorded the highest (48.87) number of eggs produced. The cost of construction was recorded to be highest in battery cage system while construction of free range facilities was at the minimum. Revenue generated from egg sold was highest (₦1384.56) in deep litter system while free range recorded the least significant (p < 0.05) (₦1301.44) value. Total cost of producing table eggs was significantly (p < 0.05) highest (₦2251.54) in battery cage, while free range had the least (₦2074.88) cost of production. Free range birds recorded the highest (₦326.56) net benefit, while the least (₦195.24) net benefit was obtained in battery cage.ConclusionIt was therefore concluded that free range management system resulted into better profit margin and could however be adopted by small scale farmers in rural areas willing to practice backyard poultry farming.

Resistance sources to root-knot nematode Meloidogyne enterolobii in Solanum species

The objective of this work was to prospect sources of resistance to root-knot nematode Meloidogyne enterolobii in Solanum species with potential to be used as rootstocks for cultivated Solanaceae. Nine accessions of Solanum sessiliflorum, 27 accessions of S. lycocarpum, 21 accessions of S. acanthodes, 22 accessions of S. scinericum and 26 accessions of S. scuticum for resistance to M. enterolobii. Rutgers and Nemadoro tomatoes were used as susceptible and resistant controls, respectively. The experiment was conducted in a greenhouse at Embrapa Vegetables, Brasília-DF, Brazil, in a completely randomized design with six replications. The experimental unit was a represented by a single plant grown in a plastic pot containing 3 L of substrate. 4000 eggs and eventual juveniles of second stage M. enterolobii were inoculated per pot. At 119 days after inoculation, gall index (Gi), egg mass index (EMI), number of eggs per root gram (NE) and reproduction factor (Fr) were evaluated. Data were subjected to analysis of variance and grouping of treatments by Scott-Knott. It was verified that S. acanthodes and S. Lycocarpum are species with high resistance to M. enterolobii, with accessions being classified identified as immune. S. scuticum also has great potential, as several resistant accessions were identified, although some accessions were quite susceptible; whereas for S. subinerme only 4 resistant accessions were identified, although all others presented a reproduction factor much lower than tomato cv. Nemadoro as control; and all evaluated S. sessiliflorum accessions were susceptible.