Tomato Plots Research Articles

Foliar Application of Sakurab (Allium Chinense G. Don) Extract on Tomato (Lycopersicon Esculentun) Production

The demand for tomatoes is constantly high all year round. They are one of the most popular crops among home gardeners and farmers worldwide. Not only are they delicious, but they are also easy to grow and could provide high returns for the space they occupy. However, tomatoes are highly sensitive to several biotic and abiotic stresses. This study aimed to evaluate two varieties of tomatoes and their interaction effects in response to the application of Sakurab leaf extract as organic foliar fertilizer and insect pest repellent. It utilized Split Plot Randomized Complete Block Design (RCBD) replicated three times with 30 plots comprising two main plots: Tomato variety (V1 – Braveheart and V2 – Diamante). Each main plot was divided into five equal sub-plots: Sakurab leaf extract concentration [ F1 – control (no foliar application), F2 – 2% foliar fertilizer (20 ml/ L of water), F3 – 5% foliar fertilizer (50 ml/ L of water), F4 – 10% foliar fertilizer (100 ml/ L of water), and F5 – 15% (150 ml/ L of water) levels of concentrations. In terms of growth parameters, results revealed that the varying levels of Sakurab leaf extract foliar application did not significantly affect the plant height, days to first flowering, days to fruiting, and the days to harvest. However, the marketable fruits per tomato plot, marketable fruits per plant, and the marketable yield of tomato plants per hectare were significantly (P < 0.05) affected by varying levels of Sakurab foliar application. Based on the findings, the Diamante variety applied with a 15% (150 ml/L of water) level of Sakurab leaf extract concentration which produced the most marketable fruits per plot and the yield per ton/ha is recommended. Further experiment using a higher level of concentration of Sakurab leaf extract such as 30%, 60%, and 90% within a controlled environment, including the assessment of pest and disease incidence is proposed.

Remote sensing and machine learning techniques for high throughput phenotyping of late blight-resistant tomato plants in open field trials

ABSTRACT The selection of late blight resistant genotypes of tomato requires many evaluations on the field. The use of machine learning models to assess late blight severity based on images from multispectral cameras onboard of unmanned aerial vehicles (UAVs) can bring efficiency and quickly in evaluations. In this work, we use remote sensing and machine learning techniques to assess late blight resistance of tomato lines grown in open field conditions. Seventy-six tomato lines, including two resistant lines and one susceptible line, were used to quantify late blight severity. Plants were arranged according to a replicated check design in a total of 132 experimental plots. Tomato plants were artificially inoculated with a Phytophthora infestans zoospore suspension. Multispectral images were obtained using an unmanned aerial vehicle. We calculated vegetation indexes (VI) using the images, which were the basis for building the Random Forest models used to predict disease severity. Two methodologies were used to predict late blight severity: Methodology 1, which used only the images from the last day of evaluation, and Methodology 2, which used the images from four days of evaluation. For Methodology 1 and 2, determination coefficients of 0.81 and 0.93 were obtained for the test set, respectively. Methodology 2 was used to predict late blight severity of the 132 field plots. Tomato plots were sorted from lowest to highest predicted severity. Resistant plots were ranked first indicating consistency of prediction. We therefore recommend Methodology 2 as a fast and practical way to predicted late blight severity in breeding populations.

Abundance of Phytoparasitic Root Nematodes Associated with Tomato (Solanum lycopersicum Mill.) in Kalaburagi, Karnataka, India

Tomato (Solanum lycopersicum Mill.) is the most commonly grown prime vegetable crop in India and all around the world. Tomato is cultivated majorly in many states of the nation including Karnataka and plays an important role in the Indian economy. The ripe tomato fruits act as the best source of vitamin A, Vitamin D and also have various antioxidant properties. Tomato crop progressively gets infested by various diseases at different stages from vegetation up to fruiting. The diseases such as bacterial leaf spot, bacterial wilt, leaf curl, fruit canker and Septoria leaf spot are caused by different Bacteria, Viruses and Fungi. Nematodes also result in root-knot, stunting and fusarium wilt diseases which may reduce the crop yield and fruit quality. The present survey was carried out from June 2021 to November 2021 in selected tomato plots of Kalaburagi district to identify different species of root nematodes affecting tomato crop in the selected study area. According to the survey results a total of six species of root nematodes were isolated and identified namely Meloidogyne spp., Globodera Spp., Paratrichodors minor, Helicotylenchus dihystera, Pratylenchus spp. and Rotylenchus buxophilus from selected study plots of Nirgudi, Bhosga, Bhosga Tanda, Gobbur, Sannur, Nadikur and Khanadal. The results suggest that Meloidogyne sps and Paratrichodors minor were most commonly recorded. The highest abundance of these nematodes recrded in Nirgudi region and in Nandikur region population of these root nematodes is least abundant.

Study of the Population Dynamics of the Leafminer, Tuta Absoluta, Pests of Tomato (Lycopersicum esculentum) in the Municipality of Ouallam in Niger

In Niger, since 2012 a new pest Tuta absoluta has appeared on tomato. Tuta absoluta is subservient not only to tomato but also to other solanaceae (potatoes, peppers etc.). All these crops can be attacked by this pest and production losses can reach 100% of the harvest, if none protective measure is taken. The objective assigned to this study is to improve tomato production in Niger through the integrated management of the tomato miner Tuta absoluta. To do this, the study focused on monitoring the dynamics of the Tuta absoluta population during the wintering period using pheromone traps and also an interview guide addressed to producers. The results showed the effective presence of the tomato leaf miner (Tuta absoluta) on the two sites monitored throughout the rainy season. The results showed that more than half of the tomato plots were attacked by Tuta absoluta and showed attack symptoms. However, the attacked plants regenerated with new organs (leaves and stems) hence the extension of tomato cultivation in Tolkoboye with the use of pheromone traps. The study of the population dynamics of Tuta absoluta shows that the average captures per week oscillate between 53.6 and 1.72 individuals during the capture period on the observation sites while the peak on the control site oscillates between 70.8 and 52 individuals. It therefore emerges from the observations that the catches of butterflies this year are lower than those of last year.

Transcriptional responses to Fusarium oxysporum f. sp. lycopersici (Sacc.) Snyder & Hansen infection in three Colombian tomato cultivars

BackgroundFusarium oxysporum f. sp. lycopersici (Fol) is a compendium of pathogenic and non-pathogenic fungal strains. Pathogenic strains may cause vascular wilt disease and produce considerable losses in commercial tomato plots. To gain insight into the molecular mechanisms mediating resistance to Fol in tomato, the aim of our study was to characterize the transcriptional response of three cultivars (CT1, CT2 and IAC391) to a pathogenic (Fol-pt) and a non-pathogenic (Fo-npt) strain of Fo.ResultsAll cultivars exhibited differentially expressed genes in response to each strain of the fungus at 36 h post-inoculation. For the pathogenic strain, CT1 deployed an apparent active defense response that included upregulation of WRKY transcription factors, an extracellular chitinase, and terpenoid-related genes, among others. In IAC391, differentially expressed genes included upregulated but mostly downregulated genes. Upregulated genes mapped to ethylene regulation, pathogenesis regulation and transcription regulation, while downregulated genes potentially impacted defense responses, lipid transport and metal ion binding. Finally, CT2 exhibited mostly downregulated genes upon Fol-pt infection. This included genes involved in transcription regulation, defense responses, and metal ion binding.ConclusionsResults suggest that CT1 mounts a defense response against Fol-pt. IAC391 exhibits an intermediate phenotype whereby some defense response genes are activated, and others are suppressed. Finally, the transcriptional profile in the CT2 hints towards lower levels of resistance. Fo-npt also induced transcriptional changes in all cultivars, but to a lesser extent. Results of this study will support genetic breeding programs currently underway in the zone.

Seasonal diversity of soil microarthropods in two different vegetable plots of Aligarh-India

Soil microarthropods are intimately linked with health and fertility of soil as well as plant productivity. In India, despite their rich faunal diversity, information on soil microarthropods diversity and interactions with variety of edaphic factors is extremely limited. The present study is carried out to observe seasonal diversity of soil microarthropods in two different vegetable plots in Aligarh. The two vegetable plots chosen in this study where predominantly Tomato (Lycopersicom esculentum) and Brinjal (Solanum melongena, family-Solaneceae) have been grown and sapling has been sown in April when plants attained a height of approximately 6″. The samples collected randomly from a depth of 5 cm. @ of four samples per month for a period of 1 year. All microarthropods extracted with the help of Tullgren funnel apparatus. Among soil microarthropods collected, Collembolans have highest average monthly density (15.20 inds./sample) in brinjal plot and greatest abundance (18.7 inds./sample) in tomato plot. A highly significant negative correlation observed between Collembolans population with reference to soil temperature (r = – 0.867, P 0.05). Neutral pH level preferably influences the Collembolans as well as Acarina (mites). Peak population buildup of Collembola and Acarina was found in spring, and winter months, whereas sharp decline in summer months was observed. Therefore, this study clearly establishes the fact that habitat difference as well as edaphic factors play important roles in buildup of soil microarthropods population.

Prevalence and Occurrence of Various Wilt Pathogens Associated with Tomato (Solanum lycopersicum L.) in Togo

In December 2015, wilt symptoms on tomato plants (Solanum lycopersicum L.) were observed on vegetable growing perimeters in Sotouboua district in Togo. The disease, manifested by wilting of the youngest leaves followed by wilting and total desiccation of plants who eventually dy, leading to losses of up to 100%, is similar to bacterial wilt. The aim of this study, was to determine the pathogen responsible for the observed symptoms. For this purpose, phytosanitary surveys were carried out on tomato plots in Sotouboua distric, in 2018. During the surveys, Tomato plants infected by wilt and the plots soil samples, were collected on CECODRI project and farmers’ plots in the district. Soil samples were analyzed for the detection of nematodes while, tomato leaves, stems and roots were directly observed under binocular loupe and after incubation in Petri dishes containing filter paper moistened with distilled water to encourage sporulation of phytopathogenic fungi. Infected tomato stems and roots were analyzed by stem-streaming and DAS-ELISA tests using Agdia inc. Ralstonia solanacearum Patho Screen Kit to detect R. solanacearum. The results of the phytosanitary surveys showed that the wilt prevalence was 100% in Sotouboua district with incidence rates of up to 100%. Analysis of diseased samples, using stem-streaming and DAS-ELISA tests, revealed that 85.11% of diseased plants were infected by R. solanacearum. No nematodes were identified in the roots of the infected plants, but in soil samples only a few nematodes were counted. No fungus was found in the plants with wilt symptoms. It appears, therefore that, the wilt on tomato plants in Sotouboua district was caused by R. solanacearum. This, in our knowledge, is the first report on R. solanacearum infection on tomato in Togo.

Eco-efficiency of tomato from Rwamagana district in Rwanda: From field constraints to statistical significance

On the request of decision-makers, the Life Cycle Assessment (LCA) framework is increasingly applied in agri-food value chains in developing countries under particularly demanding constraints. Based on the cradle-to-farm-gate LCA results of the tomato in Rwamagana district in Rwanda commissioned by the European Union, the main objectives of the paper were to validate statistically the differences in environmental impacts among expert-based types for this crop based on location and season and identify the key-drivers of these impacts. The study was developed thanks to two intensive field visits and a survey of 15 plots. The functional unit was one kg of tomato at farm-gate. Combining several statistical analyses allowed identifying three groups of plots with contrasting input profile and eco-efficiency. For most impact categories, the first group with mainly plots in marshland during wet season had the lowest impacts and the third group with plots in hillside showed the highest impacts. The yield of tomato being significantly different between marshland and hillside plots was an important driver of these results. The second group composed of plots in marshland during the dry season generally showed intermediate impacts due to the withdrawing of water for irrigation. The second group obtained a higher freshwater ecotoxicity due to a more intensive use of toxic insecticides. The factorial analysis for mixed data (FAMD) confirmed the importance of the location and the season for the eco-efficiency of tomato plots and the hierarchical clustering on principle components (HCPC) separated the tomato plots into three clusters. The generalized linear models (GLMs) validated the differences in the environmental impacts per kg of tomato between the clusters. The principal component analysis (PCA) combined to GLM revealed that only the use of water was significantly different between the three groups. Compared to existing datasets, all groups showed high freshwater ecotoxicity impacts due to the use of toxic insecticides and the excessive use of mancozeb. The third group also showed a high freshwater eutrophication in relation to P losses due to erosion and low yield. From a methodological point of view, we demonstrated in this paper that using expert-based typologies combined with adapted statistical analyses constituted a relevant approach under such circumstances.

Determination of some pesticide residues in conventional-grown and IPM-grown tomato by using QuEChERS method

The present study was conducted to determine pesticide (emamectin-benzoate, penconazole and imidacloprid) residues over tomatoes by using QuEChERS method. The method was validated by spiking tomato matrix at 0.1, 1.0, and 10.0 MRL levels of the pesticides. Tomatoes were harvested from two conventional and two Integrated Pest Management-grown fields. Laboratory samples were taken from the bulk samples. Analyses of spiked and real-field tomatoes were performed with QuEChERS procedure. Experimental samples were subjected to LC-MS/MS analysis. As indicated in “CAC/GL 40-1993,” representative sample matrix (apple) calibration was used for quantification. The overall recovery was 107.12% with a relative standard deviation of 17.96% (n = 162). Present values were within the specified recovery ranges (60-140%) and repeatability value of (RSD ≤20%) of SANCO. Analysis of field experiment samples showed that both conventional tomato plots had trace levels (less than MRL) of emamectin-benzoate and imidacloprid, whereas there were not any pesticide residues in both IPM tomato plots

Agricultural Practices Influence Salmonella Contamination and Survival in Pre-harvest Tomato Production.

Between 2000 and 2010 the Eastern Shore of Virginia was implicated in four Salmonella outbreaks associated with tomato. Therefore, a multi-year study (2012–2015) was performed to investigate presumptive factors associated with the contamination of Salmonella within tomato fields at Virginia Tech’s Eastern Shore Agricultural Research and Extension Center. Factors including irrigation water sources (pond and well), type of soil amendment: fresh poultry litter (PL), PL ash, and a conventional fertilizer (triple superphosphate – TSP), and production practices: staked with plastic mulch (SP), staked without plastic mulch (SW), and non-staked without plastic mulch (NW), were evaluated by split-plot or complete-block design. All field experiments relied on naturally occurring Salmonella contamination, except one follow up experiment (worst-case scenario) which examined the potential for contamination in tomato fruits when Salmonella was applied through drip irrigation. Samples were collected from pond and well water; PL, PL ash, and TSP; and the rhizosphere, leaves, and fruits of tomato plants. Salmonella was quantified using a most probable number method and contamination ratios were calculated for each treatment. Salmonella serovar was determined by molecular serotyping. Salmonella populations varied significantly by year; however, similar trends were evident each year. Findings showed use of untreated pond water and raw PL amendment increased the likelihood of Salmonella detection in tomato plots. Salmonella Newport and Typhimurium were the most frequently detected serovars in pond water and PL amendment samples, respectively. Interestingly, while these factors increased the likelihood of Salmonella detection in tomato plots (rhizosphere and leaves), all tomato fruits sampled (n = 4800) from these plots were Salmonella negative. Contamination of tomato fruits was extremely low (< 1%) even when tomato plots were artificially inoculated with an attenuated Salmonella Newport strain (104 CFU/mL). Furthermore, Salmonella was not detected in tomato plots irrigated using well water and amended with PL ash or TSP. Production practices also influenced the likelihood of Salmonella detection in tomato plots. Salmonella detection was higher in tomato leaf samples for NW plots, compared to SP and SW plots. This study provides evidence that attention to agricultural inputs and production practices may help reduce the likelihood of Salmonella contamination in tomato fields.

Contrasting olfactory responses of two egg parasitoids to buckwheat floral scent are reflected in field parasitism rates

Conservation biological control programs advocate the planting of flower strips alongside crops to improve the survival and effectiveness of parasitoids. Ideally, the provided food plants are highly attractive and benefit the targeted biocontrol agents without promoting pests or intraguild competition. Previous laboratory studies showed that Trissolcus basalis, an egg parasitoid of the stink bug Nezara viridula, is highly attracted to floral odors of buckwheat and that its nectar increases the wasp’s fecundity. In the field, T. basalis competes with the co-occurring parasitoid Ooencyrtus telenomicida for host eggs. Therefore, in the present study, we explored whether O. telenomicida shows similar attraction to buckwheat volatiles. We then carried out a 2-year field experiment to assess whether the laboratory-observed olfactory behaviors of both species are reflected in changed parasitism rates of stink bug eggs. Parasitism by naturally occurring egg parasitoids was measured in tomato plots with and without a margin of flowering buckwheat. Our results showed that, unlike T. basalis, O. telenomicida was repelled by the odor of buckwheat flowers. In both years, T. basalis found more egg batches and parasitized more stinkbug eggs when flower margins were present. Egg parasitism correlated positively with proximity to the buckwheat margin. In accordance with our prediction, egg parasitism by O. telenomicida occurred almost exclusively in the control plots and for a shorter period during the season. We conclude that buckwheat strips can influence intraguild competition and hypothesize that the effect was mediated by floral volatiles.

IMPACT OF INSECTICIDES ON POLLINATOR POPULATIONS: ROLE OF PHYTOSANITARY PERFORMANCE INDICATORS IN TOMATO CROPS

Agrochemicals are considered to be among the major environmental threats to pollinators, including honey bees. At the time of foraging, bees are at risk of exposure to phytosanitary treatment as a result of widespread treatment and their location, often near orchards. In Algeria, the majority of farmers systematically over-treat their orchards in order to have good quality fruits for as long as possible towards the use of an effective product. We evaluated the comparative effects of lambda-cyhalothrin and spinosad insecticide treatments on bees in tomato plots. Fluctuations of bee populations abundance were established during a 16 days period of exposure using yellow-colored plates with water placed every two days inside the experimental units. Bee populations showed very high sensitivity (0 individuals registered) to both insecticides at the homologated dose and even half dose during 10 days following application of the treatments. Depending on the estimated temporal toxicity of the respective products, differences in recovery of bee activity are presented. Consideration of indicators of the intensity of use of plant protection products is discussed.

High genetic stability of potato yellow mosaic Panama virus infecting tomato in Panama

The relevant regions in Panama involved in commercial tomato production, including the Chiriqui, Veraguas, Herrera, Los Santos and Panama Oeste provinces, were surveyed for the distribution and genetic diversity of potato yellow mosaic Panama virus (PYMPV) in the growing seasons of 2011 and 2012. A total of 28 tomato plots were surveyed and 314 individual tomato plants were sampled. DNA was extracted from each plant for a subsequent rolling circle amplification (RCA) analysis, to confirm the presence of begomovirus infections. The samples displaying a positive RCA reaction were subsequently analysed by PCR with a specific primer pair to identify PYMPV. This virus was detected in samples collected in all the above-mentioned provinces. The population structure of PYMPV was assessed by single-strand conformation polymorphism (SSCP) analysis. In total, four distinct SSCP patterns were distinguished. Based on the geographical distribution and the different patterns obtained, 42 viral isolates were selected for cloning and sequencing. Sequences obtained were compared with the ancestral sequence of PYMPV reported in Panama in 1998. These sequences showed very low variability, with two lineages probably originated by a single introduction.

Influence of grafting on growth and yield performance of two tomato cultivars grown in open field in Nigeria

Tomato production is limited in Nigeria by foliar and soil-borne diseases. Most cultivars that command a premium market are susceptible to bacterial wilt disease caused by Ralstonia solanacearum. Tomato growers need researches that support the advantages of market niches afforded by these tomatoes through the development of systems to manage diseases against loss of yields. Bacterial wilt, the major soil-borne disease in the southwestern Nigeria, was effectively managed using susceptible tomato cultivars Beske and UC82-B grafted onto resistant rootstock (cv. Tomachiva). The experiment was laid down in a randomized complete block design. Grafted cv. Beske was not affected by bacterial wilt disease both in early and late planting season, respectively. However, non-grafted cvs Beske and UC82-B experienced various degrees of disease incidence and severity ranging from 36.70% to 50% in cv. Beske, 31.70% to 35% incidence in cv. UC82-B and were significantly higher (P < 0.05) than 0% incidence in cv. Beske and 0–3.30% incidence in cv. UC82-B in both early and late planting seasons, respectively. There was significant increase (P ≤ 0.05) in yield of grafted cv. Beske up to 63.16% and 53.38% in early and late planting seasons, respectively. Grafted cv. UC82-B had 56.14% and 71.76% yield increase in early and late planting seasons, respectively. Consistent numeric and tonnage increase in fruit yield were observed in grafted tomato plots which were significantly higher (P ≤ 0.05) than in non-grafted tomato plots. In conclusion, grafting is an effective management tool for tomato growers in the southwest Nigeria to reduce risk of crop loss resulting from soil-borne diseases and could be a valuable component in an integrated pest management program.

Weeds, nitrogen and yield: measuring the effectiveness of an organic cover cropped vegetable no-till system

AbstractOrganic vegetable growers rely heavily on mechanical methods such as tillage and other forms of labor-intensive soil cultivation for weed management despite the negative effects to soil health associated with intensive soil disturbance. The use of cover crops and no-till (NT) vegetable production represents an alternative approach to weed control that can enhance rather than degrade soil health; however, there are challenges inherent with this practice and previous results in vegetable production have been mixed. Field experiments were conducted over 2 yr at the Clemson Student Organic Farm to examine the effects of tillage [NT versus conventional tillage (CT)] on weed development and management in organic tomato and summer squash production under different nitrogen (N) fertility regimes, and to assess soil N dynamics in both systems. Squash yields were similar between tillage treatments in both years. NT tomato yields were 43% greater than CT yields in 2014, whereas CT tomato yields were 46% greater than NT yields in 2015. Squash and tomato yields per unit of management labor (time) were significantly greater in NT compared with CT treatments for both years. There were no statistical differences in squash and tomato yields between N fertilization treatments in either year. Pre- and post-season soil N results were mixed. Pre-season soil N levels were significantly higher in NT tomato plots in 2014 but similar between tillage treatments in tomato plots in 2015 and in squash plots both years. Post-season soil N levels in tomato plots were similar between tillage treatments both years. Post-season soil N levels were significantly higher in NT squash plots in 2014 and in CT squash plots in 2015. Roller-crimped NT mulches provided adequate early-season weed suppression in both years and saved considerable weed management and seedbed preparation labor. Overall, the results demonstrated that organic NT is a viable method for reduced tillage summer vegetable production in the southeastern Piedmont region.

Biology of Prodiplosis longifila Gagné and population fluctuation in tomato crops sprayed with insecticides

Se llevaron a cabo estudios de laboratorio para determinar parámetros de historia de vida del mosquito de las agallas Prodiplosis longifila, una plaga clave del tomate. Huevos de P. longifila colectados en cultivos de tomate eclosionaron, en promedio, en 1,2 días y el tiempo de desarrollo (larva I hasta adulto) fue alrededor de 14 días a condiciones ambientales. La proporción de sexos (macho: hembra) de P. longifila fue de 1:1.03. La longevidad promedia del macho y de la hembra (1,1 días ambas) se incrementaron después de consumir azúcar. Ensayos de campo para determinar la fluctuación poblacional de P. longifila se desarrollaron en tres lotes comerciales de tomate en Colombia bajo aspersiones de insecticidas tipo calendario. Los números promedio de larvas en todos los lotes fueron mayores durante las dos últimas semanas que durante las dos primeras semanas de muestreo. El número de larvas aumentó aún bajo la aspersión de insecticidas. El número de larvas aumentó después de la floración, sugiriendo que los adultos fueron atraídos a las flores de tomate y probablemente las utilizaron como fuente de azúcar. La infestación (%) estuvo correlacionada positivamente con el número promedio de larvas/brote foliar, sugiriendo el potencial de este método indirecto para monitorear larvas de P. longifila en tomate. La aspersión de insecticidas en cultivos de tomate para controlar P. longifila en un esquema basado en el calendario no redujo la densidad de larvas.

Uniformity trials size for estimating cherry tomato plot size

The aim of this study was to determine how the size of the uniformity trial influences the estimation of cherry tomato plot size. The size of plot required to evaluate the mean length of fruit per plant, mean fruit width per plant, mean fruit weight per plant, number of bunches per plant, number of fruits per bunch, number of fruits per plant and total weight of fruits per plant was estimated in uniformity trials in two greenhouses: large (250 m²) and small (200 m²). In each greenhouse and row, and for each variable, 3000 plot size estimates were obtained by resampling and used to determine of 97.5 and 2.5% percentiles. Each row needs to be treated as a specific uniformity trial because of significant row variability. It is recommended that uniformity trials are carried out on 35 plants in the large greenhouse and 23 plants in the small greenhouse in order to estimate cherry tomato production variables at a confidence interval of 30% of the mean.

Insecticidal Effects on the Spatial Progression of Tomato Yellow Leaf Curl Virus and Movement of Its Whitefly Vector in Tomato.

Commercial management of whitefly-transmitted Tomato yellow leaf curl virus (TYLCV) typically relies on insecticide control of whitefly vectors as a first line of defense. We quantified this effect in crop tunnel studies, with validation in a tomato field setting. Tomato yellow leaf curl virus-infected and Bemisia tabaci (Gennadius)-infested source plants were planted at the beginning of tunneled rows to serve as inoculum source, so that movement of whiteflies and TYLCV symptoms could be tracked down the length of the tunnel over time. Tunnel study results showed that proximity to the source plant was a more important factor than insecticide treatments. Insecticide-treated tomato transplants did tend to suppress whitefly incidence and slowed TYLCV movement in comparison with the untreated check; however, tomato plants planted closer to the source plant had higher incidence of whiteflies and TYLCV infection, regardless of treatment. In a large tomato plot study with a controlled inoculum source, insecticide treatments significantly reduced the spread of TYLCV. When uninhibited by insecticide treatment, 80% of the TYLCV spread was restricted to <15 m from the source plant (<11 m in the validation study), with insecticide treatment generally reducing the distance and magnitude of this spread.

Assessment of a New Approach for Systematic Subsurface Drip Irrigation Management

This paper aimed to assess the reliability of a new approach that provides systematic irrigation management based on fixed water suction in the vadose zone. Trials were carried out in the experimental farm of IRA Gabès on subsurface drip irrigated (SDI) tomato plot. The SDI system was designed so that the soil water content is to be maintained within prescribed interval ascertaining the best plant growth. Irrigation management was systematically monitored by water suction evolution in the vadose zone. Recorded results showed that all-over irrigation season lateral pressure head ranged within 93.3 ± 20.0; 119.95 ± 53.35 and 106.6 ± 40.0 mb, respectively, at the upstream, middle, and downstream. The correspondent lateral pressure head distribution uniformity ranged within 97.1% and 99.6%. Soil water content varied within 0.2175 ± 0.0165; 0.206 ± 0.0195 and 0.284 ± 0.100 beneath the inlet, the behalf, and the lateral end tip. The correspondent soil water distribution uniformity was higher than 80.7% all-over irrigation season. Based on the recorded results, the proposed approach could be a helpful tool for accurate SDI systems design and best water supplies management. Nevertheless, further trials are needed to assess the approach reliability in different cropping conditions.

Impact of Distance from the Forest Edge on The Wild Bee Diversity on the Northern Slope of Mount Slamet

&lt;p&gt;In agricultural landscape in northern slope of Mount Slamet, diversity of wild bee species as pollinator depend on forested habitats. This study aimed to assess the effects of distance from the forest edge on the diversity of wild bees on strawberry and tomato crops. This study was conducted from July 2014 to October 2014. The experimental fields contained tomato and strawberry with a total area of 4 ha (2 ha each) and divided into five plots based on distance from the forest edge (0, 50, 100, 150, and 200 m). Wild bee was catched with kite netting in 7.00 -9.00 in ten consecutive days. Wild bee diversity differed according to distance from the forest edge, the highest value was at 0 m for strawberry plots (H’ = 2.008, E = 0.72 and Chao1= 16) and for tomato plots, the highest diversity was at 50 m from the forest edge (H’ = 2.298, E = 0.95 and Chao1= 11) and the lowest was at 200 m in both plots. Wild bee species richness and abundance decreased with distance, resulting in the minimum diversity and abundance of wild bee at 200 m from forest edge in both crops.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;&lt;p&gt;&lt;strong&gt;How to Cite&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Widhiono, I., &amp;amp; Sudiana, E. (2016). Impact of Distance from the Forest Edge on The Wild Bee Diversity on the Northern Slope of Mount Slamet. &lt;em&gt;Biosaintifika: Journal of Biology &amp;amp; Biology Education&lt;/em&gt;, 8(2), 148-154.&lt;/p&gt;