Turmeric leaf waste as a bio-based strategy for managing Pratylenchus coffeae in banana: lab-to-field validation with molecular evidence

Effects of soil amendments, foliar sprayings of silicon and selenium and their combinations on the reduction of cadmium accumulation in rice

Nematicidal activity of the leaf powder and extracts of <i>Myrtus communis</i> against the root‐knot nematode <i>Meloidogyne javanica</i>

Oilseed rape (Brassica napus) characteristically has high N uptake efficiency and low N utilization efficiency (NUtE, seed yield/shoot N accumulation). Determining the NUtE phenotype of various genotypes in different growth conditions is a way of finding target traits to improve oilseed rape NUtE. The aim of this study was to compare oilseed rape genotypes grown on contrasting N supply rates in pot and field experiments to investigate the genotypic variations of NUtE and to identify indicators of N efficient genotypes. For 50 oilseed rape genotypes, NUtE, dry matter and N partitioning, morphological characteristics, and the yield components were investigated under high and low N supplies in a greenhouse pot experiment and a field trial. Although the genotype rankings of NUtE were different between the pot experiment and the field trial, some genotypes performed consistently in both two environments. N-responder, N-nonresponder, N-efficient and N-inefficient genotypes were identified from these genotypes with consistent NUtE. The correlations between the pot experiment and the field trial in NUtE were only 0.34 at high N supplies and no significant correlations were found at low N supplies. However, Pearson coefficient correlation (r) and principal component analysis showed NUtE had similar genetic correlations with other traits across the pot and field experiment. Among the yield components, only seeds per silique showed strong and positive correlations with NUtE under varying N supply in both experiments (r = 0.47**; 0.49**; 0.47**; 0.54**). At high and low N supply, NUtE was positively correlated with seed yield (r = 0.45**; 0.53**; 0.39**; 0.87**), nitrogen harvest index (NHI, r = 0.68**; 0.82**; 0.99**; 0.89**), and harvest index (HI, r = 0.79**; 0.83**; 0.90**; 0.78**) and negatively correlated with biomass distribution to stem and leaf (r = −0.34**; −0.45**; −0.37**; 0.62**), all aboveground plant section N concentration (r from −0.30* to −0.80**), N distribution to the vegetative parts (silique husk, stem and leaf) (r from −0.40** to −0.83**). N-efficient (N-responder) genotypes produced more seeds per silique and had significantly higher NHI and HI than did N-inefficient (N-nonresponder) genotypes. In conclusion, across the pot and field experiments, the 50 genotypes had similar underlying traits correlated with NUtE and seeds per silique may be a good indicator of NUtE.

The present study was carried out to analyze the potential of fungi isolated from the rhizosphere of soybean, brinjal, tomato, and potato plants. The density of fungi varied in the pot soil and rhizosphere after Paecilomyces formosus MD12 treatment. The P. formosus MD12 population was 6.3 ± 0.13 × 104 CFU g−1 in the pot planted with brinjal, and the population increased in the rhizosphere (6.72 ± 0.41 × 104 CFU g−1). P. formosus MD12 was cultured in the production medium, and the supernatant was used for egg inhibition studies on a root-knot nematode parasite, Meloidogyne incognita. It was revealed that maximum egg inhibition (94.7 ± 6.2%) was obtained at 100% concentration of extract. The culture supernatant from P. formosus MD12 affected the development of M. incognita juvenile, and the mortality rate was maximum after 96 h (95 ± 6%). Mortality was reduced when treated with 25%, 50%, and 75% supernatant. At 1 × 107 mL−1 of spore suspension, we found reductions of 71.6 ± 3.3% nematode populations in the soil, 60.7 ± 2.2% from the root, and 63.6 ± 2.4% egg mass compared with the control in the pot experiment. The culture supernatant applied at the 10% level showed a maximum mean reduction of the nematode population in roots (72.4 ± 2.2%), soil (77.9 ± 2.5%), and egg masses (73.2 ± 1.5%), respectively. The presence of P. formosus MD12 in a soil environment could antagonize nematode parasites and improve soil amendment. The P. formosus MD12 strain showed good biocontrol ability against the root-knot nematode, M. incognita, under in vitro and green house experimental condition.

Copper and iron isotope fractionation by plant uptake and translocation is a matter of current research. As a way to apply the use of Cu and Fe stable isotopes in the phytoremediation of contaminated sites, the effects of organic amendment and microbial addition in a mine-spoiled soil seeded with Helianthus annuus in pot experiments and field trials were studied. Results show that the addition of a microbial consortium of ten bacterial strains has an influence on Cu and Fe isotope fractionation by the uptake and translocation in pot experiments, with an increase in average of 0.99 ‰ for the δ(65)Cu values from soil to roots. In the field trial, the amendment with the addition of bacteria and mycorrhiza as single and double inoculation enriches the leaves in (65)Cu compared to the soil. As a result of the same trial, the δ(56)Fe values in the leaves are lower than those from the bulk soil, although some differences are seen according to the amendment used. Siderophores, possibly released by the bacterial consortium, can be responsible for this change in the Cu and Fe fractionation. The overall isotopic fractionation trend for Cu and Fe does not vary for pot and field experiments with or without bacteria. However, variations in specific metabolic pathways related to metal-organic complexation and weathering can modify particular isotopic signatures.

The effects of antibiotic contamination on vegetable safety and the ecological risks of soil after returning livestock and poultry manure to the land require sufficient future attention. Tetracycline antibiotics (TCs) are often detected at high concentrations in livestock manure and vegetable production soils. Recently, pot experiments and field investigation methods have often been used to understand the effects of TCs contamination on the vegetable safety and ecological risks of soil, whereas field experiments are employed less frequently. This study investigated the distribution characteristics of TCs in the soil-vegetable system following manure application using a combination of pot and field experiments. The human health risks of the edible parts of Chinese flowing cabbage were assessed using the health risk quotient method based on the acceptable daily intake (ADI-HQ), and the ecological risks of TCs-contaminated soils were evaluated using the risk quotient method associated with the species sensitivity distribution model (SSD-RQ). The results showed that oxytetracycline (OTC) was the major type of TCs in Chinese flowering cabbage based on both the pot and field experiments. The maximum contents (dry weight) of OTC in the aboveground parts of the Chinese flowering cabbage for the pot and field experiments were 29.25 μg·kg-1 and 45.03 μg·kg-1, respectively, whereas those of their underground parts were 87.32 μg·kg-1 and 135.44 μg·kg-1, respectively. Meanwhile, higher contents of TCs were detected in Chinese flowering cabbage collected from the field experiment than those from the pot experiment. OTC was also the major type of TCs in soil from both the pot and field experiments, with their contents up to 604.30 μg·kg-1 and 1013.68 μg·kg-1, respectively. Higher residual contents of three TCs were detected in soils collected from the field experiment than those from the pot experiment. Under the experimental conditions, with the except that OTC in Chinese flowering cabbage from the field experiment would pose medium health risks (HQ>0.1) to children, the contents of three TCs in other treated Chinese flowering cabbage would pose low health risks (HQ ≤ 0.1) to adults and children. In the pot experiments, three TCs present in Chinese flowering cabbage would pose low health risks (HQ ≤ 0.1) to adults and children. Additionally, the TCs in soils with manure application from the pot and field experiments may have posed both moderate or high levels of ecological risks (HQ>0.1 or HQ>1). Therefore, the effects of antibiotic contamination on vegetable safety and their potential ecological risks on soil following manure fertilization need to be given special attention.

أجريت ثلاث تجارب على الأواني في Agric. الدقة. محطة ، فاك. الزراعة ، جامعة الأزهر. مدينة نصر خلال مواسم 2011/2012 ، 2012/2013 ، كان على كل واحد دراسة تأثير أربع عبوات غير معدنية لكل N و P و K على جودة ثلاثة أصناف من القمح المصري ، مثل سخا 93 ، مصر 1 و بني سويف 6. عبوة النيتروجين 75 كجم نتروجين / فدان (تحكم) ، 75 كجم نيتروجين / فدان + رش السيستين مرتين (كل 150 جزء في المليون) ، 37.5 كجم نيتروجين / فدان + سماد نيتروجين (سيريالين) + رش مرتين سيستين و 37 ، 5 كجم نيتروجين / فدان + سماد أحيائي (بيوجين) + رش مرتين للسيستين. عبوات السماد الفوسفوري هي الفوسفور ، حامض الهيوميك 6٪ ، الفوسفور + حامض الهيوميك 6٪ والسيطرة (بدون الفوسفور). عبوة سماد البوتاسيوم هي البوتاسيوم ، رماد الموز 4٪ ، البوتاسيوم + الموز 4٪ والسيطرة (بدون سماد البوتاسيوم). من ناحية أخرى تم إجراء تجربة حقلية في جلسة 2013/2014 في منطقة الكلاج بمحافظة القليوبية مصر لتأكيد النتيجة التي تم الحصول عليها من تجارب الوعاء. ومع ذلك ، تم تصميم تجارب الأواني في تصميم عشوائي كامل ، وكانت التجربة الميدانية في تصميم القطع المنقسمة. أظهرت النتائج وجود فروق معنوية بين أصناف القمح الثلاثة المختبرة مثل محتوى بروتين الحبوب ومحتوى الغلوتين الرطب والجاف. أعطى بني سويف 6 صفات جودة الحبوب أعلى من صنف سخا 93 و مصر 1 في موسم الكاش تحت تجارب الأصيص والحقلية. اختلفت الخواص التكنولوجية معنويا بين معاملات عبوات الأسمدة النيتروجينية المدروسة خلال مواسم النمو الثلاثة تحت الوعاء أو التجارب الحقلية. في التجربة الثانية كانت هناك فروق معنوية بين معاملات عبوات السماد الفسفوري المختلفة في كلا الموسمين تحت تجربة القدر والتجربة الحقلية. سجلت معاملات P4 و P3 أعلى قيم للخواص التكنولوجية مقارنة بالمعاملة P1 في المواسم الثلاثة في الأواني أو التجارب الحقلية. أظهر تأثير التفاعل بين عبوات (var. X P.) أن الصفات التي تم دراستها كانت معنوية بالتفاعل بين العاملين المدروسين. أخيرًا ، في التجربة الثالثة ، لوحظت فروق معنوية بين عبوات الأسمدة البوتاسية الأربعة المدروسة لجميع الصفات المدروسة تحت التجربة الحقلية والوعائية في كلا الموسمين ، بينما أعطت معاملات K4 أعلى قيم الصفات التكنولوجية. كما احتلت معاملة K3 المرتبة الثانية وأنتجت أعلى قيم للصفات السابقة في كلا الموسمين. وعليه ، فقد أظهرت أصناف القمح الثلاثة مسئولية كبيرة تجاه عبوات الأسمدة المختلفة من النتروجين والفوسفور والبوتاسيوم فيما يتعلق ببعض الخصائص التكنولوجية في التجارب الحقلية والوعائية في ظل هذه الظروف.

The distribution of root and bulb parasitic nematode in garlic crops at various elevation and the effect of abiotic factors on their distribution were investigated. The survey was done at the centers of garlic production area in Central Java, Indonesia. Soil abiotic factors such as temperature, pH, and C-Organic were measured in each location of sampling. Nematodes were analyzed using incubation and white head tray technique modification. Correlation and regression were used to determine the effect of abiotic factors. The results showed that the five locations with different elevations were positive for Ditylenchus dipsaci distribution. These nematodes were found in various elevation with different populations in the range of 8.00-16.67 nematodes per 100 g of soil and 14.34 to 26.67 nematodes per 2 g of bulb. The highest density of the nematode population both in bulb and soil was in Tegal at elevation &lt;1000 m a.s.l. while the lowest nematode population both in soil and root were found in Temanggung at an elevation of 1000-1200 m a.s.l. Abiotic factors, such as temperature has a positive correlation with D.dipsaci nematode populations in bulb and soil, while pH has a negative correlation with nematode populations. C-organic has a positive correlation in abundance of nematode populations in the soil and negative in abundance of nematode populations in bulb.

Effects of intercropping and soil amendment with urea and calcium oxide on the incidence of bacterial wilt of tomato and survival of soil‐borne <i>Pseudomonas solanacearum</i> in Taiwan

The effectiveness of Calciphos (500�C calcined calcium-aluminium C-grade rock phosphate from Christmas Island), Queensland rock phosphate (low carbonate substituted apatite, from Duchess deposit, Northern Queensland [QRP]), and granular North Carolina rock phosphate (highly carbonate substituted apatite from U.S.A. [NCRP]) were compared with the effectiveness of monocalcium phosphate (MCP) fertilisers in pot and field experiments. Three different lateritic soils from south-western Australia and different plant species were used. In the pot experiment, the effectiveness of the fertilisers was measured relative to freshly applied MCP for 5 successive crops. Subterranean clover, oats, triticale and barley were grown for about 1 month before harvesting. In the field experiment, the same plants were grown, and the effectiveness of the fertilisers was measured relative to freshly applied triple superphosphate for 3 successive years. On a dry matter yield basis, the effects of freshly applied rock phosphate dressings measured in the pot experiment were in a similar range to those measured in the field experiment for the same soil types, and the same plant species, indicating that pot trials can substitute for field trials for the evaluation of the initial effectiveness of fertilisers. However, the residual effectiveness values for both MCP and the RPs were generally much lower for the pot experiment, indicating that pot experiments cannot replace long-term field experiments for the reliable measurement of residual effectiveness of fertilisers. For the pot experiment, the relative effectiveness values of freshly applied NCRP and Calciphos for all soils were 0.2-0.3 and 0.1-0.2 respectively. The corresponding values for the field experiment were 0.1-0.3 for NCRP and 0.1 for Calciphos. For the pot experiment, the relative effectiveness of freshly applied QRP on all soils ranged from 0.03 to 0.1, compared with from 0.1 to 0.3 for the field experiment. The relative effectiveness of all fertilisers declined markedly with successive crops (i.e. crops 2-5) in the pot experiment, whereas in the field experiment the relative effectiveness of QRP and NCRP showed no systematic change for the 3-years of the experiment. For the pot experiment the relative effectiveness of residual MCP decreased to about 0.3, 0.2 and 0.1, compared with 0.5, 0.2 and 0.5 for the field experiment for West Dale, South Bodallin and Gibson soils, respectively. For the pot experiment and for all soils the residual relative effectiveness of NCRP and Calciphos was about 0.01- 0.04, compared with 0.003-0.02 for QRP. For the field experiment the corresponding values were 0.05-0.2 for NCRP and Calciphos and 0.01-0.1 for QRP. For both the pot and the field experiments the relationship between yield and phosphorus content was sometimes dependent on fertiliser type.

The study explored the use of low cost soil amendments in reducing lead and cadmium uptake in tobacco. High levels of these metals in tobacco are of concern because of their toxicity and cumulative nature in tobacco consumers. Tobacco was planted in soils amended with cow manure and hydroxyapatite (HA), and non-amended sandy-loamy soil containing 60.57±3.74 μg/g lead and 33.95±0.49 μg/g cadmium in field and pot experiments. Tobacco leaves harvested after 75 days were dried, acid digested and their metal contents determined using atomic absorption spectroscopy (AAS). Cow manure reduced cadmium uptake by 67.20% and 71.75% in field and pot experiments while 1.5% HA reduced lead uptake by 39.69% in field experiments. Pot experiments had higher metals uptake than field experiments while fertilizer treatments recorded highest uptake. However, the levels were within WHO/FAO limits, indicating that amending medially polluted soils with cow manure and HA results in safe harvests of tobacco.

Heavy metal contaminated food crops are one of the major public health concerns these days. The present study evaluates the Cd uptake in some promising wheat varieties subjected to soils amended with different types of organic fertilizers/matter. For this purpose, both pot and field experiments were conducted at the same time in Sargodha, Pakistan. Cadmium uptake in soil and different wheat plant parts were higher in the pot experiment than that in the field experiment. In both experiments, Cd ranged from 0.075 to 0.030 mg/kg in soil, 0.64 to 1.01 mg/kg in root, 0.63 to1.00 mg/kg in shoot and 0.65 to 1.01 mg/kg in grains. Among all soil amendments, farm-yard manure was found to be very effective in mitigating the uptake of Cd in wheat plants. Of all wheat varieties, Gold-16 and Ihsan-16 showed maximum Cd uptake, whereas the minimum Cd uptake was displayed by cv. DHharabi-11. In both experiments, all different indices showed values lower than 1 except the bio-concentration factor. Overall, Cd absorption observed in the present soil-wheat system was lower than the standard Cd absorption values. This study recommends that farmers may use organic soil amendments in this area to increase the fertility of soil. But regular examination practices must be carried out in this area, to limit the exposure to Cd hazards of public being provided Cd contaminated grains.

Plant-parasitic nematodes (PPNs) cause serious damage to agricultural production worldwide. Currently, because of a lack of effective and environmental-friendly chemical nematicides, the use of microbial nematicides has been proposed as an eco-friendly management strategy to control PPNs. A nematicidal bacterium GC-7 was originally isolated from the rice rhizosphere, and was identified as Pseudomonas rhodesiae. Treatment with the fermentation supernatant of GC-7 in vitro showed a highly lethal effect on second-stage juveniles of Meloidogyne graminicola, with the mortality rate increasing to 95.82% at 24 h and egg hatching significantly inhibited, with a hatch inhibition rate of 60.65% at 96 h. The bacterium significantly reduced the level of damage caused by M. graminicola infestations to rice (Oryza sativa) in greenhouse and field experiments. Under greenhouse conditions, the GC-7 culture efficiently reduced the gall index and nematode population in rice roots and soils, as well as inhibited nematode development compared to the control. Under field conditions, application of the GC-7 consistently showed a high biocontrol efficacy against M. graminicola (with a control efficiency of 58.85%) and promoted plant growth. In addition, the inoculation of GC-7 in M. graminicola-infested rice plant fields significantly suppressed final nematode populations in soil under natural conditions. Furthermore, activities of plant defense-related enzymes, peroxidase, polyphenol oxidase, and phenylalanine ammonia-lyase were remarkably increased in plant roots treated with GC-7 compared with roots that were challenge to M. graminicola. Moreover, quantitative real-time PCR analysis showed that GC-7 significantly enhanced the expression of defense genes (PR1a, WRKY45, JaMYB, AOS2, ERF1, and ACS1) related to salicylic acid, jasmonic acid, and ethylene signaling pathways in rice roots after inoculation with GC-7 at different levels. The results indicated that GC-7 could be an effective biological component in the integrated management of M. graminicola infecting rice.

The scarab beetle, Temnorhynchus baal (Reiche & Saulcy) (Coleoptera: Scarabaeidae), becomes a key pest of strawberry, especially after increasing its cultivated area and economic importance in Egypt. Few entomopathogenic nematode (EPN) species/strains were tested against this pest, where only a foreign species had good effect comparable to the native populations tested previously. Thirty-eight indigenous Heterorhabditis indica populations were tested against the most damaging, third instar larvae of H. baal in two soil types, where strawberry cultivation prevails. The corrected mortality induced by indigenous H. indica population in T. baal larvae was (99.52 and 98.57%) for 15 populations in the sandy soil and 23 in loamy sand soil, respectively. Overall average of infective juveniles (IJs) per T. baal larva was about (41,000). The average of emerged nematode-IJs from the infected grubs for the 15 EPN populations in sandy soil, (46,960 IJs/grub), was significantly (P < 0.001) higher than that (36,502 IJs/grub) of 23 EPN populations in loamy sand soil. The insignificant difference was detected in the reproductive capacity among nematode populations in T. baal larvae in sandy or loamy sand soil. A highly significant difference was found among total IJ numbers collected 10, 18, 26, and 30 days post-inoculation in sandy or loamy sand soil. The persistence of the H. indica populations in the soil varied greatly. Obtained results suggest further use of at least ten populations of such indigenous nematodes under field conditions.

Pot and field experiments were conducted to evaluate bioavailability of Cu in contaminated paddy soil (PS) and phytoremediation potential by Elsholtzia splendens as affected by soil amendments. The results from pot experiment showed that organic manure (M) applied to the PS not only remarkably raised the H2O exchangeable Cu, which were mainly due to the increased exchangeable and organic fractions of Cu in the PS by M, but also stimulated plant growth and Cu accumulation in E. splendens. At M application rate of 5.0%, shoot Cu concentration in the plant increased by four times grown on the PS, so as to the elevated shoot Cu accumulation by three times as compared to the control. In the field trial, soil amendments by M and furnace slag (F), and soil preparations like soil capping (S) and soil discing (D) were performed in the PS. Soil capping and discing considerably declined total Cu in the PS. Application of M solely or together with F enhanced plant growth and increased H2O exchangeable Cu levels in the soil. The increased extractability of Cu in the rhizosphere of E. splendens was noted, which may have mainly attributed to the rhizospheric acidification and chelation by dissolved organic matter (DOM), thus resulting in elevating Cu uptake and accumulation by E. splendens. Amendments with organic manure plus furnace slag (MF) to the PS caused the highest exactable Cu with saturated H2O in the rhizospheric soil of E. splendens after they were grown for 170 days in the PS, thus achieving 1.74 kg Cu ha− 1 removal from the contaminated soil by the whole plant of E. splendens at one season, which is higher than those of the other soil treatments. The results indicated that application of organic manure at a proper rate could enhance Cu bioavailability and increase effectiveness of Cu phytoextraction from the contaminated soil by the metal-tolerant and accumulating plant species (E. splendens).