Screenhouse Experiments Research Articles

Interactive effect of cadmium and lead on shoot dry matter yield and nutrient composition of spinach (Spinach oleracea)

Lead (Pb) and cadmium (Cd) are the most hazardous heavy metal contaminants for the environment. The environmental Cd and Pb concentrations are steadily increasing due to nondestructive nature of both. When present in soil, they are generally taken up by the plant’s roots and distributed to different tissues thereby interfering with the plant growth and development. Under such circumstances their synergistic and antagonistic interactions need to be studied. In the present study, a screenhouse experiment was conducted and interactive effects of Pb (0, 25, 50, 100 and 200 mg/kg) and Cd (0, 10, 25, 50 and 100 mg/kg) were studied on dry matter yield (DMY), macronutrients content, Pb and Cd content in leaves and shoot of 60 days grown spinach crop. It was recorded that the spiking of Pb and Cd, decrease the macronutrients (P, K, S, Mg and S) concentration in spinach shoot, resulted in reduced DMY. Also, higher accumulation of these heavy metals in spinach shoot further responsible for reduction in shoot DMY. It was observed that the DMY decreased by 6.6, 16.4, 23.0 and 31.1% with 25, 50, 100 and 200 mg Pb/kg spiking in Cd spiked soil. Further, the combined application of Pb and Cd increased the Cd concentration by 1.7, 6.2 and 8.6% at 50, 100 and 200 mg Pb/kg soil respectively. Moreover, in equilibrated soil, mean DTPA-Pb and DTPA-Cd increased significantly with increase in their respective levels of spiking.

MANAGEMENT OF ARMYWORM (SPODOPTERA FRUGIPERDA) INFESTATION ON MAIZE PLANT UNDER DIFFERENT PLANTS IN OWERRI, IMO STATE

Fall Armyworm (Spodoptera frugiperda) infestation on maize is a widespread and persistent problem which can be effectively controlled through natural or organic approaches. This study investigated Azadirachta indica and Cymbopogon citratus leaf aqueous extracts to control Spodoptera frugiperdainfestation on maize through laboratory and screen house experiments. Gas chromatography-mass spectrometry (GC-MS) analysis was used to determine A. indica's compounds and abundance. In both contact and feeding bioassays, increasing doses of A. indica and C. citratus extracts resulted in a linear increase in S. frugiperda mortality and antifeedant effects. A. indica and C. citratus extracts at 10% w/v increased S. frugiperda mortality best. Chlorifylos had the greatest mortality rate (98.70%), followed by Azadrachtha indica (70.56%) and Cymbopogon citratus (65.60%), while acetone extract had the lowest mortality rate (2.21%). The highest antifeedant activity was observed in A. indica (76.10%), followed by Cymbopogon citratus (55.63), acetone (7.25%), and water (5.73%). A linear increase in the antifeedant activity was observed as the concentration of the extracts increased. High foliar damage was observed in (untreated, water and water plus 0.1% soap with mean leaf damage scores of 5.48, 5.37, and 4.17, respectively. Chlorpyrifos (1.24%) was the most effective in reducing foliar damage. There was no significant difference in the severity of foliar damage on maize plants that received A. indica (3.40) and C. citratus (3.23) A total of 43 compounds were identified in the A. indica extract. These results show the pesticidal activities of A. indica and C. citratus for the sustainable management of S. frugiperda infestations.

Phenotypic Screening and Marker-Assisted Validation of Sources of Aphis craccivora Koch Resistance in Cowpea (Vigna unguiculata L.).

Aphis craccivora significantly affects cowpea (Vigna unguiculata L.) production, leading to yield reductions. Management strategies encompass physical barriers and biological and chemical methods, which can be costly and detrimental to the environment. Host-plant resistance offers a more sustainable alternative. This study evaluated cowpea genotypes in a screenhouse experiment. Tswana and B261-B were resistant, while B301, B259, and ER7 showed a tolerance phenotype. Tswana exhibited a low aphid population and minimal plant damage, probably due to suppression of reproduction and fecundity. Conversely, IT97K-556-6, SARI-21KTA-6, SARC 1-57-2, B013-F, B339, and Blackeye were susceptible to aphids, as shown by high aphid populations and dense sooty molds. Severe damage to plant vigor may be linked to direct aphid feeding and reduced photosynthesis efficiency. SNP1_0912 and CP 171F/172R markers confirmed aphid resistance in Tswana and ER7 as well as in the IT97k-556-6 and SARI-21KTA-6 controls. The inverse susceptible phenotype in the control group suggests that the markers may not function properly due to negative interactions between quantitative trait loci (QTL) and environmental factors. This could also indicate the presence of different aphid biotypes that severely damage Western African breeding lines. This study offers essential insights for breeding aphid-resistant cowpea varieties. Future efforts will involve sequencing Tswana to identify more resistance sources and create novel markers.

Sulphur-mediated plant resistance elicits phenolic defense in canola to reduce aphid reproduction and improve crop yield in canola

Rising concerns over chemical insecticides are demanding alternative pest management methods. The present study planned to explore the potential of elemental-ES, bio-sulphur-BS, compost-Cp, and compared to insecticide (Carbosulfan) and untreated controls for sustainable management of canola aphids (Brevicoryne brassicae). Split doses were more useful (screen house experiments) over single dose (in field). BS mixed with Cp provided best results to suppress aphid reproduction. Insecticide effects were instant but not long-lasting. Sulphur mixture also improved crop yield and oil contents; however, plant height was maximum in insecticide. RP-HPLC revealed activation of different phenolic defense chemicals (three flavonoids, five phenolic acids, and six hydroxycinnamic acid) in canola. Phenolic compounds were higher in sulphur-treated plants but their distribution patterns were altered in leaves, shoots, and seeds. The results could be extended to insect pests on other crops. However, further genetic studies are needed to discover the intricate pattern of sulphur resistance.

Influence of Tithonia diversifolia biochar on selected soil physicochemical properties, leaf nutrient concentrations and broccoli growth

A screen house experiment was conducted to evaluate the effects of Tithonia diversifolia biochar on selected soil physicochemical properties. The study included five treatments with Tithonia diversifolia biochar applied at rates of 0, 10, 20, 30, and 40 t ha− 1, arranged in a completely randomised design with three replicates. Surface soil (0–15 cm depth) from the Iwo soil series (sandy loam) was collected from the Teaching and Research Farm of Adekunle Ajasin University, Akungba-Akoko, Ondo State, Nigeria. Each 10 kg soil sample was thoroughly mixed with the respective biochar rate and maintained at field moisture capacity for four weeks in the screen house before sowing broccoli seeds. Soil samples were analyzed for particle size distribution, bulk density, porosity, moisture content, pH, organic carbon, total nitrogen, available phosphorus, exchangeable potassium, calcium, and magnesium. Agronomic parameters measured included broccoli height, number of leaves, leaf area, stem girth, and fresh weight of broccoli biomass. Leaf nutrient concentrations of broccoli were also determined. Data were subjected to analysis of variance, and significant means were separated using Duncan’s multiple range test at p = 0.05. Results indicated that biochar-amended plots significantly improved soil physicochemical properties compared to the control. Biochar application also significantly increased broccoli height, number of leaves, leaf area, stem girth, leaf nutrient concentrations, and fresh weight of broccoli biomass. The application of tithonia biochar at rates of 10, 20, 30, and 40 t ha− 1 increased the fresh weight of broccoli biomass by 13%, 38%, 26%, and 23%, respectively, compared to the control. The application rate of 20 t ha− 1 was found to be the most beneficial, enhancing leaf nutrient concentrations and growth parameters. This study recommends the use of Tithonia diversifolia biochar as a soil amendment to improve soil quality of sandy loam and enhance broccoli productivity and quality.

THE EFFICACY OF Moringa oleifera EXTRACT AS A BIOFUNGICIDE ON THE FUSARIUM WILT OF TOMATO (Solanum lycopersicum)

Fungi cause a lot of ruin of agricultural crops leading to negative impact on economy and health risks to consumers due to the toxin produced by the fungi. Bio-control using plant extracts is an ecofriendly and a promising method engaged in controlling pathogenic fungi. Screenhouse experiment was conducted to study the efficacy of Moringa oleifera as a bio-fungicide for managing Fusarium oxysporium wilt of tomato (Solanum lycopersicum) at the department of Plant Science and Biotechnology, Faculty of Science of Federal University, Oye-Ekiti, Ekiti State. The main objective of the study was to investigate the potential of aqueous M. oleifera extract as bio-control agent in controlling wilt of tomato and to determine the M. oleifera concentration that is most effective against the pathogen under screenhouse condition. The plants were treated for 10 weeks with different concentrations of M. oleifera (25%, 50%, 75%)while water served as the control.The experiment was carried out in a randomized block design (RBD) and designed as PLOT (1, 2, 3 and 4) with four (4) replicates. The investigated growth and yield parameters include shoot height, number of leaves, leaf length and leaf width, number of flowers and number of fruits. Allthe data collected were subjected to Analysis of Variance (ANOVA) and the results revealed that the use of M. oleifera extract was very effective in suppressing F. oxysporium in tomato. The average total yield per time was obtained in tomato plants treated with 75% M. oleifera extract, followed by those treated with 25% and 50% extracts respectively, while the lowest was observed from the control plants.

Evaluation of Groundnut Genotypes for Resistance to Early Leaf Spot Disease and Preharvest Aflatoxin Contamination

Aflatoxin caused by Aspergillus flavus is a major field to storage contaminant in groundnut seed production, whereas defoliation diseases in groundnut caused by Passalora arachidicola and Nothopassalora personata are two of the most yield-limiting biotic stresses. The present study was to identify groundnut genotypes with resistance to leaf spot disease and preharvest aflatoxin contamination. Thirty-three groundnut genotypes originating from crosses between Schubert × 43-09-03-02 and TS32-1 × 60-02-03-02 including three checks: Manipinta, Chinese and ICGV03401 were evaluated in screenhouse and field studies. In the screenhouse experiment, the groundnut genotypes were arranged in a Complete Randomized Design with three replications. The field experiment was laid in a 9 × 4 alpha lattice design with three replications. Results revealed that A. flavus population in the soil increased when the fields were inoculated with the A. flavus isolate. Again, results show that these groundnut genotypes namely, L024, L030, L078B, L086A, L092 and L096, showed resistance to leaf spot disease infection. Also, except for L020B, which respectively showed a B and B aflatoxin of 71.5 and 72.0 ppb under field conditions and 1 2 132.1 and 131.5 ppb in pots, the remaining genotypes did not accumulate any aflatoxin at the preharvest level. In conclusion, the study identified groundnut genotypes L024, L030, L078B, L086A, L092 and L096 to be resistant to early leaf spot disease and preharvest aflatoxin contamination. These genotypes could be tested in the future for their yield and stability under diverse environments and released as varieties.

Understanding the Impact of Zinc and Boron Applications on Growth and Yield Attributes in Potato

Research examines the impact of zinc (Zn) and boron (B) on the growth, and yield of potato plants. The screen house experiment used four treatments: T1 (Control), T2 (Zn 5g/L), T3 (B 2g/L), and T4 (Zn 5g/L + B 2g/L). Growth characteristics were evaluated, such as the emergence percentage, plant vigor, number of stem /meter2, plant height, and stem diameter. In addition, essential yield metrics such as number of tubers, tuber weight (g), dry matter content, and specific gravity were also assessed. The findings indicated that concurrent administration of T4 had a substantial positive impact on the plant's vitality, height, stem thickness, and stem density per square meter compared to the control group. This suggests a cooperative influence of these micronutrients on the growth of plant structures. However, in terms of yield qualities, the use of Zn alone T2 led to the greatest tuber weight, dry matter content, and specific gravity. Showing that Zn plays a crucial role in maximizing tuber growth and quality. The treatment T4 enhanced yield parameters compared to the control, but it did not exceed the effects of either Zn or B individually in T2 and T3. This emphasizes the intricate interaction between these nutrients. However, when it comes to maximizing yield attributes in potato cultivation, using Zn alone may be more successful. The results indicate that customizing the management of micronutrients could optimize the growth and output of potatoes, hence enhancing agricultural productivity. Additional research is advised to investigate the most effective dosages and combinations

Management of Root-Knot Nematode (Meloidogyne spp.) on Kiwifruit Seedlings using Different Plant Extracts, Biocontrol Agents, and Chemical Nematicides

Root-knot nematodes (RKN), (Meloidogyne spp.), are the major biotic factor responsible for the limiting production of Kiwifruit in Nepal including Kiwifruit orchard of Warm Temperate Horticulture Center, Nepal. Hence, there is a pressing demand for nematicides that are both easily accessible and cost-effective while being environmentally friendly. A screenhouse experiment was conducted in the Summer of 2023 with an objective to evaluate the effects of different plant extracts, bio-control agents, and chemical nematicides against RKN on Kiwifruit seedlings. The experiment was set up in a Completely Randomized Design with three replications and eight treatments which include the extracts of Allium sativum and Lantana camara, Trichoderma viride, Pseudomonas fluorescens, Cartap hydrochloride, Fosthiazate, Inoculated control and Uninoculated control. The results revealed that Trichoderma viride proved to be the most effective in reducing the nematode population, displaying a low root gall index of 3.11, a minimal reproductive factor of 0.24, and a high percentage of nematode control at 91.71%. It was also found to be efficient in promoting the growth parameters of Kiwifruit seedlings. Additionally, regression analysis exhibited a significantly positive interaction between root gall index and reproductive factor, while indicating a negative interaction between reproductive factor and growth parameters. Therefore, T. viride (@ 20 gm per 2000 cm3 of soil) should be soil drenched before the seedlings are transplanted into the main field for effective and sustainable management of RKN. Nevertheless, further research is needed to determine the efficacy of T. viride in infested roots of Kiwifruit trees in field condition of Kiwifruit orchard.

Evaluation of elite rice lines for resistance to Kenya blast fungus (Magnapothe Oryzae)

Blast resistance tends to often break down, these necessitate search-resistant genes. The screen house experiment was conducted in 2019 and 2020. A total of 56 rice genotypes, (Elite lines, monogenic lines, and local), were screened against ten Kenya isolates of Mangnaporthe oryzae. The establishment was by direct seeding of previously sprouted seeds. A completely Randomized Design (CRD) with two replicates was adopted. Inoculation was done 21 days after planting. Plants were maintained in the moist chamber (26–28 0C) for 48 hrs, then moved into an incubation chamber (25 ◦C ± 2). Disease assessment commenced 48 hours after inoculation until 21 days to full infection. Disease evaluations were performed according to the Standard Evaluation System of IRRI. Polymerase Chain Reactions (PCR) were carried out, blast resistant loci were identified using varied genetic markers that co-segregate with specific resistant loci Analysis was implemented in R version 3.3.2 (R Core Team, 2016). BLUPs were computed, in a mixed model to estimate the random effect of the genotypes. The data was subjected to analysis of variance and means separated by Tukey’s test at P < 0.05. Cluster analyses were performed in JMP software version 11.2 for Windows. Seven genotypes (IR12A311, IR10M210, IR74, 1R02A127, IR09A130, R66 and IR10N230) were more susceptible, IR13N152 and IR14F711 were more resistant to all Isolates. The monogenic lines IRBLsh-B and IRBLkh-K3 which carry blast-resistant genes, were susceptible to at least seven Kenya isolates. The local checks (Basmati 370, BAS 270 (pi9), BW196, and BAS370 (pi9) were highly susceptible. The genotype IR12F711 was consistently resistant to all Kenya Isolates.

Identification and biocontrol potential of entomopathogenic nematodes, Steinernema siamkayai occurring in western Thailand against the common cutworm, Spodoptera litura Fabricius (Lepidoptera: Noctuidae) under laboratory and screenhouse conditions

AbstractThe common cutworm, Spodoptera litura, is a serious insect pest of many vegetables and crops worldwide. Entomopathogenic nematodes (EPN) have been utilized as biological control agents for controlling various insect pests, including the larvae of S. litura. Many indigenous EPN have been recognized to be more effective in specific field applications. Among the 160 soil samples collected in undisturbed areas of western Thailand, three samples tested positive for EPN. Three indigenous EPN were identified as Steinernema siamkayai namely, EPNKU63, EPNKU70 and EPNKU85, based on ITS and D2/D3 expansion region analysis of the 28s rRNA genes. Additionally, genetic analysis of the symbiotic bacteria using recA rRNA sequences confirmed their identity as Xenorhabdus stockiae namely, PEPNKU63, PEPNKU70 and PEPNKU85. To evaluate their initial biocontrol potential against the 6th instar larvae of Galleria mellonella, virulence assays were conducted. The application of 100 infective juveniles (IJs)/insects resulted in the mortality of 80–100% of G. mellonella larvae after 72 h. When symbiotic bacteria were applied at 1 × 106 cells/insect, they exhibited 63–93% mortality against G. mellonella larvae after 120 h. In further laboratory tests, three S. siamkayai isolates achieved 100% mortality of 3rd instar Spodoptera litura larvae within 72 h, with LC50 values ranging from 29 to 30 IJs/insect. In screenhouse experiments, it was revealed that all S. siamkayai isolates displayed substantial virulence, ranging from 62% to 74%, against 3rd instar S. litura larvae within 72 h. This study demonstrates the biocontrol potential of S. siamkayai in controlling S. litura larvae.

Effect of drought at different reproductive stages on yield and yield components of some cowpea (<i>Vigna unguiculata l. Walp</i>) varieties in Lapai, Niger State, Nigeria

Drought is one of the most unfavorable abiotic factors that can affect the growth and yield of cowpea. Drought at different reproductive stages can interfere with the morphological processes of plants. Therefore this research aim to determine the effect of drought at different reproductive stages on yield and yield components of some cowpea varieties. A screen house experiment was conducted at the Botanical Garden of Biological Science Department, Ibrahim Badamasi Babangida, University during the 2022 cropping season The three cowpea varieties used were; FUAMPEA 1, FUAMPEA 2 and ITK89KD-288 which were planted and subjected to water stress at three different reproductive stages which included; early flowering stage, early pod set stage, early seed filling stage and a well-watered treatment to serve as control. The treatments were arranged in a Complete Randomized Design (CRD) in three replications. Cowpea yield attributes evaluated were; number of pods per plant, pod length, pod weight per pot, number of seeds per pod, 100 seed weight, total grain yield per pot and estimated grain yield per hectare. Results revealed that variety was highly significant (p≤0.01) for pod length, total grain yield per pot and estimated grain yield per hectare. On the other hand, drought was significant (p≤0.05) for pod weight per pot. Variety however was not significant for number of pods per plant, number of seeds per pod and 100 seed weight. Drought showed a highly significant effect (p≤0.01) on number of pods per plant, pod length, pod weight per pot, number of seeds per pod, 100 seed weight, total grain yield per pot and estimated grain yield per hectare. Water stress at early seed filling stage significantly reduced total grain yield per plot and total grain yield per hectare. Drought at different reproductive stages affects the morphological and physiological processes of cowpea as a crop. This is an indication that water is very crucial during the growth and yield of cowpea.

Nutrients Uptake and Fruit Yield of Tomato (Lycopersicon Esculentum Mill.) Produced Using Home Sorted and Municipal Organic Materials as Nutrient Sources.

Tomato (Lycopersicon esculentum Mill.) is one of the most popular crops with a unique role in human diets especially in Nigeria. Nutritional quality of fruit is a reflection of uptake by the plant. The study investigated the uptake of Nitrogen, Phosphorus, Potassium, Calcium and Magnesium uptake by tomato with incorporation of home and municipal sorted solid waste. Screenhouse experiment was carried out at the College of Plant Science and Crop Production, while field experiment was conducted at the Directorate of University Farms, Federal University of Agriculture (Latitudes 7°13ʹN and 7°20ʹN and Longitudes 3°20ʹE and 3°28ʹE) during the early and late seasons of 2019. Roma VF and Ibadan-local varieties as test crop. The screenhouse experiment was factorial in Completely Randomized Design. The treatments were: composted municipal solid waste; composted home sorted waste; pyrolyzed municipal solid waste and pyrolyzed home sorted waste at the rate of 0, 5, 10 and 20 tha-1 each. The field experiment was set up in a randomized complete block design with incorporation of waste treatments at 10 t ha-1, all in three replicates. The treatments mentioned above for screenhouse were also used for field experiment. Data collected were subjected to Analysis of Variance and the means were separated using Duncan’s Multiple Range Test (p<0.05). The study was carried out in the wet and dry seasons. Nutrients (N, P, K, Ca and Mg) uptakes by plants were determined after laboratory analysis using nutrient concentration x dry matter (kg ha-1). Treatments had significant effects on the fruit yield of tomato. Composted home sorted waste at 5 t ha-1 resulted in highest uptake of nitrogen (5.32 mg kg-1), phosphorus (2.87 mg kg-1), potassium (26.10 mg kg-1) and magnesium (9.74 mg kg-1) in screenhouse compared with control and other treatments. Pyrolyzed wastes enhanced the fruit yield and nutrient uptake by plant relative to composted wastes in both seasons on the field. Pyrolyzed home sorted waste (PHSW) enhanced nitrogen uptake at early (186 kg ha-1) and late (108 kg ha-1) seasons. Pyrolyzed wastes (PHSW and PMSW) increased phosphorus uptake of 573 kg ha-1 and 507 kg ha-1 respectively in the early season while the highest phosphorus uptake of 339.6 kg ha-1 was observed with PHSW in the late season. Pyrolyzed municipal solid waste (PMSW) increased potassium uptake in both early (22.21 kg ha-1) and late (12.55 kg ha-1) seasons compared to control and other treatments applied. It was concluded that composted and pyrolyzed home sorted wastes improved the fruit yield and nutrient uptake in organic tomato production, and thus recommended for optimal production of tomato.

Formulation of Nano-fertilizer and Phytochemical Screening of orange peel were utilized to enhance the growth of Vigna radiata

Nanotechnology has developed into one of the most valued fields of sciences in the current century owing to the introduction of revolutionary changes in several disciplines of sciences. A key product of nanotechnology, i.e., nanoparticles (NPs) are abundantly used in modern research due to their novel applications. Orange peel contains vital nutrients that can be recycled into valuable material used for different purposes. In this study, we synthesized nano fertilizer from orange peel and tested its potential for promoting the growth of Vigna radiata and reducing the population of root rot pathogens. Nano-fertilizer extract was subjected to physical and chemical analyses for characterization. Transmission electron microscopy indicated spherical nanoparticles with sizes ranging between 18.22nm and 61.05nm. While the X-Ray diffraction analysis the peaks were observed at 2ɵ value of 19.830, 20.550, 21.240, 24.440, 27.330 and 29.770 which represented the similarity with urea slandered peak. The Synthesized nano-fertilizers contained phenols, steroids, triterpenes and xanthoproteins. In a screen house experiment, the nano fertilizer extract was administered to the seeds of Vigna radiata. The research demonstrated that increasing the dose of orange peel extract enhanced germination percentage by positively influencing plant growth characteristics. Meanwhile, a high concentration of orange peel amendment successfully reduced the colonization and infection percentage of root rotting pathogens when compared to the positive and negative controls.

Potential of Calabash (Lagenaria siceraria) and Sweet Potato (Solanum tuberosum) for the Remediation of Dichlorodiphenyltrichloroethane-Contaminated Soils in Tanzania

A study was conducted to test the potential of calabash, sweet potato, pumpkin, simsim and finger millet to phytoaccumulate dichlorodiphenyltrichloroethane (DDT) and its metabolites from NHC Morogoro- and PPO Tengeru-contaminated sites. Parallel field and screenhouse-potted soil experiments were performed to assess the efficacy with which the test plants phytoaccumulate DDT from the soil. In the screenhouse experiment, treatments were laid out following a split-plot arrangement in a completely randomized design (CRD), with the main plots comprising two DDT concentration levels–low (417 mg kg−1) or high (2308 mg kg−1)—and the plant species Cucurbita pepo, Lagenaria siceraria, Ipomoea batatus, Sesamum indicum and Eleusine coracana were considered as subplots. A field experiment with the same crop species as the treatments was laid out in a randomized complete block design, and both experiments were performed in triplicate. In addition to determining the concentration of persistent organic pesticides in the soil profile, parameters such as the total DDT uptake by plants, shoot weight and shoot height were monitored in both potted soil and open field experiments. Overall, calabash and sweet potato exhibited the highest (4.63 mg kg−1) and second highest (3.45 mg kg−1) DDT concentrations from the high residual DDT potted soil experiment. A similar trend was observed when the two plants were grown in low DDT soil. Sweet potato recorded the highest shoot height and weight in the potted soil experiments, indicating that increasing amounts of DDT had a minimal effect on the plant’s growth. Although sweet potato outperformed calabash in the amounts of DDT concentration in the shoots under open field experiments, the uptake of DDT by calabash was the second highest. Calabash—a wild non-edible plant in Tanzania—presents a potential phytoremediation alternative to edible and much studied pumpkin.

Gamma irradiation of eggplant seeds influences plant growth, yield and nutritional profile in M1 generation

The study examines agromorphological traits and nutrient compositions in three genotypes of eggplants (Solanum melongena ‘African Beauty F1’ and ‘Melina F1’ and S. aethiopicum ‘Kotobi’) grown from seeds irradiated by gamma rays (γ-ray) with 100 Gy. Experiments were carried out in the screenhouse and experimental field of Crop Science Department, University of Calabar, Nigeria. Completely randomised design with four replications and randomised complete block design with three replications was used in the screenhouse and field experiments respectively. Eggplant × γ-ray effect reduced (p ≤ 0.05) seedling emergence, plant height and number of leaves in the nursery at 2 and 4 weeks after sowing. In the field, these traits were consistently lower for irradiated Melina F1 and Kotobi (p > 0.05) at ten weeks after transplanting. Irradiated African Beauty F1 had the highest (p ≤ 0.05) upper canopy leaf area (429.54 cm2), higher (p > 0.05) plant height and stem width; lower (p > 0.05) number of branches and leaves. Un-irradiated and irradiated Kotobi had the highest (p ≤ 0.05) fruit load, lower (p ≤ 0.05) fruit volume, weight and yields over four harvest intervals. Carbohydrate and energy contents of Kotobi fruits grown from 100 Gy gamma-ray irradiated seeds were concurrently improved (p ≤ 0.05). Gamma ray irradiation had both positive and negative influences on the agromorphological traits, mineral composition and nutrient profile of eggplants. However, 100 Gy dose of irradiation had a negative effect on fruit characteristics in general. From the results of this study, inconsistent variations in the agromorphological traits of the irradiated eggplants of the three varieties were reported. Therefore, the goal of mutation breeding in eggplant should not undermine the importance of the eggplant genotype as well as the actual radiation dose.

Virulence and Molecular Detection of Cassava Mosaic and Brown Streak Virus Genes on Elite Mutant Cassava Lines

Unavailability of germplasm with Cassava Brown Streak Disease (CBSD) and Cassava Mosaic Disease (CMD) tolerance genes remains the main bottleneck towards management of the two diseases in tropic and sub-tropic regions in Africa. We assessed the pathogenicity of two viruses and established the presence of genes linked to CBSD and CMD among some elite cassava lines using field techniques and PCR methods. The screen-house experiment was arranged in split plot in completely randomized block design replicated thrice. Severity data was done on a scale of 1 - 5 at an interval of 14 days post inoculation. Symptomatic fresh leaves were used in the extraction of genomic deoxyribonucleic acid and amplification done using markers linked to African cassava mosaic virus (ACMV), separated bands scored as present (+) or absent (-) and visualized under UV trans-illuminator. Virulence and pathogenicity results showed higher tolerance to CBSD and CMD under single inoculation. In contrast, dual inoculation synergistically increased severity expression leading defoliation at early stages of growth. DNA amplification found no CBSD and CMD alleles in CAS1. However, some traces of the alleles were amplified on CAS2, CAS3, KME3 and KME4. Mutant cassava lines exhibited low severity compared to parental lines which were genetically different in terms of viral genes detected by the ACMV linked markers.

Effect of flamboyant flower (Delonix regia) powder on root knot nematodes (Meloidogyne incognita) infestation on tomato plant (Solanum lycopersicum) in Yola, Adamawa State

Plant Parasitic Nematodes (PPN) are regarded as one of the major challenges of sustainable tomato production in the world. Their control which involves the use of synthetic chemicals is being restricted because of their toxicity coupled with the environmental risk associated with their use. To this effect this study was carried out to evaluate the effect of flamboyant flower powder on M. incognita inoculated on tomato plants as an alternative control strategy of PPN. Screen house experiment (potted experiment) was conducted at the landscape garden of Modibbo Adama University Yola to evaluate the efficacy of plant powder for the control of root- knot nematode in tomato plant. The experimental design used was the Completely Randomized Design (CRD) with five treatments replicated three times. D. regia powders were incorporated at different levels into the bucket each containing 4kg of sterilized soil. The plant powder was incorporated at the rate of 40g, 30g, 20g and 10g (T1, T2, and T3) respectively and T4 with no level of powder 0g. D. regia powder and 40g gave the best effect on M. incognita in the potted experiments as higher plant height, number of leaves; fresh shoot weight, galling index and least final nematode of both soil and roots were recorded. Therefore, from these findings, D. regia at 40g exhibited nematicidal effect on M. incognita in tomato plant followed by 30g, 20g, and 10g respectively. The nematicidal characteristics exhibited by this plant material (flamboyant flower) might be due to some phytochemical constituents present in the plant material. The control plant has least plant height, number of leaves, fresh shoot weight, plant fruit and higher fresh root weight as well as galling index and highest final root and soil nematode population.

Growth, Yield Attributes and Metabolite Components of Thickhead (Ebolo) (Crassocephalum crepidioides Benth.) as Affected by Soil Amendment

A screenhouse experiment was conducted to determine the growth, yield attributes and bioactive components of thickhead (ebolo) as affected by soil amendments. Treatments were soil type (fertile soil and degraded land respectively amended with NPK @300kg/ha (F1), NPK@150kg/ha (F2), Poultry Manure@10t/ha (F3), Poultry Manure @5t/ha (F4), NPK @ 150kg/ha + Poultry Manure @5000t/ha, (F5), NPK @ 75kg/ha + Poultry Manure @ 2500t/ha (F6) and unamended control. Data were collected on soil properties, growth and biomass yields of thickhead and chemical, proximate and bioactive components of leaves. Results showed that soil type and amendment significantly affected growth, yield and bioactive components of thickhead. Growth of thickhead improved significantly for soil collected under fallow vegetation (S1) while application of NPK and poultry manure combination at 0.375g + 12.5g per plant significantly enhanced most of the measured variables of thickhead. Fertilizer amendment of soils enhanced leaf sodium, potassium, calcium and magnesium contents, poultry manure amendment improved moisture content and crude protein, while NPK increased significantly leaf ash and fat contents. Post-cropping chemical analysis of treated soils showed increases in pH, organic carbon, nitrogen, organic matter, available P, K, Na, Ca, and Mg of fertilizer-amended soils compare with the unamended. Thickhead (ebolo) can be grown both on fertile and degraded soils, soil amendment using NPK-poultry manure combinations enhanced the growth, yield and nutrition of thickhead and is recommended for its production.

Comparative Evaluation of Fe-Impregnated Filter Paper and Some Conventional Phosphorus Extractants for Assessing Phosphorus Availability in Some Amended Soils of Southwest Nigeria

ABSTRACT Iron-impregnated filter paper (Fe-Pi) was evaluated as phosphorus (P) extractant in four soils of Ogun state, southwest Nigeria in a screenhouse experiment. The experiments lasted for 8 weeks. Soil P contents were extracted at 0, 4, and 8 weeks after the incorporation of amendments (cattle manure, poultry manure, and wood ash) using Fe-Pi, Bray-1, Bray-2, Mehlich-1, Hunter, and Olsen extractant. Agronomic variables were taken fortnightly from grown maize plants and later harvested at 8 weeks, residual effects of the treatments were also evaluated. Maize dry matter weight (DMW) and P uptake were also measured. Results indicated that a linear relationship existed among the extractants with significant coefficient at p ≤ .001. Fe-Pi established a strong relationship with the conventional extractants in the following order: Bray-1 (R 2 = 0.99) > Bray-2 (R 2 = 0.98) > Hunter (R 2 = 0.96) > Mehlich-1 (R 2 = 0.86) > Olsen (R2 = 0.82). Fe-Pi had a significant relationship with P uptake and DMW. Phosphorus uptakes under the animal manure amendments were statistically higher than uptake in control and woodash amended soils. Therefore, the study concluded that Fe-Pi was a good predictor of plant available P and had significant relationship with Bray-1, thus it could be considered for the estimation of soil available P in soils of southwest Nigeria.