Efficacy of Purpureocillium lilacinum AUMC 10149 as biocontrol agent against root-knot nematode Meloidogyne incognita infecting tomato plant

Root-knot nematode Meloidogyne incognita is among the biotic factors which has greatly affected both the yield and the quality of the tomato crop. The egg parasitic nematode, Purpureocillium lilacinum (Pl) is considered as one of the most promising agents in controlling and overcoming this plant pathogen. The nematicidal effect of the native isolate Pl AUMC 10149 on second stage juvenile’s survival and egg hatching of M. incognita at different times of exposure was tested in vitro. The obtained data showed that Pl gave a maximum percentage of J2 mortality (97.6%) and egg hatching inhibition (79.8%) after 72 hours of exposure. The potentiality of Pl as well as Bio-Nematon to control M. incognita infecting tomato was conducted using different times of application in vivo. Nine treatments with five replicates were used for such bioagents compared with the nematicide Oxamyl. Each seedling was inoculated with 1000 J2s of nematode/pot and 10 mL of Pl (1x1010 CFU/mL) or Bio-Nematon spore suspension (1x108 CFU/mL) 10mL/pot. The results indicated that the most effective treatments in reducing nematode population, number of galls and egg masses of M. incognita in plant roots was performed with treatment by Pl pre-planting and post-infection with Pl (Rf 1.9) giving a significant enhancement in plant length (64.9%), fresh weight (72.52%) and shoot dry weight (163.41%) without negatively impacting environment. Therefore, the present study confirmed that using P. lilacinum AUMC 10149 can be used as a practical supplement to environmentally friendly disease management of root-knot nematodes in Egypt.

Life history parameters and predation capacities of Nesidiocoris volucer: a new biological control agent for tomato crop

Whiteflies are one of the major pests of tomato under greenhouses, and their control partly relies on biocontrol strategies. Among those biocontrol agents, parasitoids or predators are widely used. However, the introduction of a biocontrol agent in a new area is not trivial. For that reason, we investigated the use of a tropical native mirid, Nesidiocoris volucer (Hemiptera: Miridae), for the biological control of whiteflies among other insect pests on tomato crops under greenhouses in the subtropical island of La Réunion, France. Nesidiocoris volucer life history traits and plant injury were examined. Nymphs developed and survived between 15 and 30°C and required on average 49.41 days at 15°C and on average 10.50 days at 30°C to develop (nymph survival >94%). At 25°C, each female produced on average 65 eggs. Nesidiocoris volucer was able to feed on several prey species, but performed better on whiteflies than on spider mites or thrips. No N. volucer feeding injury was observed on tomato. Nesidiocoris volucer has also been found in tropical countries of Africa, and we believe that the data presented on this natural enemy could be of great importance for the biocontrol of whiteflies in tropical areas.

Different Organic Fertilisation Systems Modify Tomato Quality: An Opportunity for Circular Fertilisation in Intensive Horticulture

The valorisation of vegetal waste as a source of crop nutrients constitutes a circular strategy to improve the sustainability of intensive horticultural production systems. The main goal of this study was to evaluate the effects of organic amendments derived from vegetal residues on the yield and quality of tomato. The following fertilisation treatments were carried out: fresh vegetal residues (4 kg m−1), compost (3 kg m−1), and vermicompost at two different doses (3 and 9 kg m−1), all derived from previous tomato crop vegetal residues, an organic treatment with goat manure (3 kg m−1), and a control mineral fertigation treatment. The highest yield was obtained with conventional mineral fertigation management, followed by vermicompost treatments at two different doses (3 and 9 kg m−1), with no statistical differences. The organic treatments with fresh crop residues, compost and goat manure resulted in lower yield. Regarding quality parameters, the lycopene content was higher in the mineral fertilisation and vermicompost at 3 kg m−1 treatment, while the other antioxidants measured were more concentrated in tomatoes fertilised with vermicompost treatment at 9 kg m−1 and goat manure. The plant nutrient management with vermicompost is the best circular solution, as it allows to reintegrate the residues generated in previous crop cycles into the soil, obtaining a yield equal to chemical input management and tomatoes with high nutritional quality.

Tomato Yield and Quality Response to Water Application Technique and Management

Tomato (Lycopersicon esculentum Mill) is one of the most important and has the highest acreage of any vegetable crop in the world. Such quantitative analysis is based on the assessment of data from sequential collections of plant traits linked to environmental conditions, as well as yield potential under optimal growth conditions. The objective in this study was to evaluate the performance of tomato crop under furrow, basin and hosepipe irrigation techniques in Kabos, Serere District of Eastern Uganda. The materials and methods used in this study included tools like water pump (model DCX2-50D), Tomato variety Rionex, weighting scale, CROPWAT 8.0 software, CANOPEO software among others. Generally, quantitative techniques through several experiment designs were used. Daily and monthly weather variables, in-situ primary datasets of plant height, canopy cover percentages and fruit characteristics, and weight of harvested tomatoes were measured at three growth stages and analyzed using RCBD experiment with six treatments and four replications. Findings showed that overhead treatments had lowest rate of rotten yield compared to basin and furrow but had highest rate of discolored fruits attributed to sunshine and impact of water pressure during irrigation. Rotting of yield was highest in basin treatments. The rotting was attributed to water logging, poor drainage that accelerated fungal infection in the tomatoes. Furrow treatments had better drainage which reduced quantity of nonmarketable yield. There was no significant difference on the weight of tomatoes below 65g. This meant that fruit weight was independent of irrigation method. Treatments under hosepipe irrigation-overhead. Conclusively, water management practices have big impact on the crop yield giving a relationship that yield is directly proportional to water management practices, which however, should be followed by detailed soil and water analysis through such studies. The Safe-Water-for Food (SWFF) target can be reached and eventually reduce on the global hunger syndrome.

The economic of production of vegetable crops grown in northern Omdurman, Khartoum State Sudan

The economic of production of vegetable crops grown in northern Omdurman, Khartoum State Sudan This study was carried out to estimate the profitability in terms of gross margins ol'the main vegetable crops grown in the area. Sampled farmers were randomly selected through a field survey during 2006/2007 agricultural season, and the collected data was subjected to descriptive statistics and gross margin analysis, in addition to the estimation of the benefit cost ratio. The results revealed that the vegetable crops under investigation arc profitable to farmers. Tomato crop scored the highest gross margin, followed by onion and lastly potato crop. Agricultural operation was the highest cost item for onion and tomato crops, while the agricultural inputs recorded the highest item for potato crop

Tomate (Solanum lycopersicum) production and bacterial canker management during COVID-19

<p>The tomato (<em>Solanum lycopersicum</em>) is part of the food basket of Mexicans and is the most consumed vegetable worldwide. Mexico is one of the main producer and exporter countries, the main market to export is the United States of America. The pandemic caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2) seriously affected the economy and consequently the production and distribution of basic foods, including tomatoes. This work summarizes the experiences derived from the production, detection and phytosanitary management of <em>Clavibacter</em> <em>michiganensis</em> subsp. <em>michiganensis</em> during the July–December 2020 season in a tomato crop under macro tunnel located in Copándaro, Michoacán, Mexico. Agriculture, as an essential economic activity in the production of basic foods, must remain active as it is an unconfined productive process, with a low risk of contagion, and it’s a necessary activity for the economic support of agricultural workers.</p>

Evaluation of Natural and Factitious Food Sources for Pronematus ubiquitus on Tomato Plants

Pronematus ubiquitus (McGregor) is a small iolinid mite that is capable of establishing on tomato plants. Once established, this mite has been shown to control both tomato russet mite, Aculops lycopersici (Tryon) (Acari: Eriophyidae), and tomato powdery mildew (Oidium neolycopersici L. Kiss). In the present study, we explored the effects of a number of alternative food sources on the oviposition rate in the laboratory. First, we assessed the reproduction on food sources that P. ubiquitus can encounter on a tomato crop: tomato pollen and powdery mildew, along with tomato leaf and Typha angustifolia L. In a second laboratory experiment, we evaluated the oviposition rate on two prey mites: the astigmatid Carpoglyphus lactis L. (Acari: Carpoglyphidae) and the tarsonemid Tarsonemus fusarii Cooreman (Acari: Tarsonemidae). Powdery mildew and C. lactis did not support reproduction, whereas tomato pollen and T. fusarii did promote egg laying. However, T. angustifolia pollen resulted in a higher oviposition in both experiments. In a greenhouse trial on individual caged tomato plants, we evaluated the impact of pollen supplementation frequency on the establishment of P. ubiquitus. Here, a pollen addition frequency of every other week was required to allow populations of P. ubiquitus to establish.

SE-CapsNet: Automated evaluation of plant disease severity based on feature extraction through Squeeze and Excitation (SE) networks and Capsule networks

Diseases in plants harm the quantity of the overall food production as well as the quality of the yield. Early detection, diagnosis and treatment can greatly reduce losses, both economic and ecological. Intuitively, reduction in the use of agrochemicals due to timely detection of the disease, would greatly help in mitigating the environmental impact. In this paper, the authors have proposed an improved feature computation approach based on Squeeze and Excitation (SE) Networks, before processing by the original Capsule networks (CapsNet) for classification, for estimating the disease severity in plants. Two SE networks, one based on AlexNet and another on ResNet have been combined with Capsule networks. Leaf images for the devastating Late Blight disease occurring in the Tomato crop have been utilized from the PlantVillage dataset. The images, divided into four severity stages i.e. healthy, early, middle and end, are downscaled, enhanced and given as input to the SE networks. The feature maps generated from the two networks are separately given as input to the Capsule Network for classification and their performances are compared with the original CapsNet, on two image sizes 32X32 and 64X64. SE-Alex-CapsNet achieves the highest accuracy of 92.1% and SE-Res CapsNet achieves the highest accuracy of 93.75% with 64X64 image size, as compared to CapsNet that results in 85.53% accuracy. The classification accuracies of six state-of-the-art CNN models namely AlexNet, SqueezeNet, ResNet50, VGG16, VGG19 and Inception V3 are also presented for comparison purposes. Accuracy as well as precision, recall, F1-score, validation loss etc. measures have been recorded and compared. The findings have been validated by implementing the proposed approaches with another dataset, achieving similar resultant accuracy measures. The implementation was also accomplished with datasets after noise addition in six different variations, to verify the robustness of the proposed model. Based on the performances, the proposed techniques can be exploited for disease severity assessment in other crops as well and can be extended to other areas of applications such as plant species classification, weed identification etc. In addition to improved performance, with reduced image size, the proposed methodology can be utilized to create a mobile application requiring low processing capabilities, to be installed on reasonably priced smartphones for practical usage by farmers.

Use of Vermicompost in the Control of Rhizoctonia sp: Impact on Tomato (Solanum lycopersicum L) Production

The area planted for vegetable production is increasing in Côte d'Ivoire while crop yields are decreasing due to low soil fertility, poor application of mineral fertilizers and poor plant development due to pest pressure. The trial carried out at the experimental site of the University Jean Lorougnon Guédé of Daloa, Central-Western Côte d'Ivoire, aims at evaluating the potential of vermicompost to reduce the attacks of the Rhizoctonia sp fungus on the tomato crop and increase its production. The trial was carried out using the Fischer randomized block design where four treatments were repeated four times. Four substrates, composed of mixtures of soils and doses of vermicompost (0, 20, 40 and 60 t/ha), inoculated with the fungus, were used for the cultivation of tomato in pots. Agronomic and phytosanitary parameters were evaluated on tomato plants at the end of the trial. The results showed that the production increased with the addition of vermicompost and this, the higher the dose of vermicompost added. The health of tomato plants was also improved by the reduction of Rhizoctonia sp attacks, especially with the 60t/ha dose, for which the disease severity and incidence indices were the lowest, 15% and 14%, respectively, against 41% and 38% obtained with the control. Vermicompost could be used to control fungal diseases of tomato and improve its production.