Postharvest Quality Of Tomatoes Research Articles

Effect of lemongrass and chili pepper oils on the quality of ripe tomato fruits stored under tropical ambient temperature

Postharvest quality of tomato (Solanum lycopersicum L.) fruits treated with lemongrass (Cymbopogon citratus L.) and chili pepper (Capsicum annuum L.) oil was evaluated. Tomato variety Roma fruits of uniform size and weight at the red stage of ripening were overlaid with lemongrass oil only (L1P0), chili pepper oil only (L0P1), or mixtures in a ratio 1:1 (L1P1), and 1:2 (L1P2 and L2P1). Control (L0P0) was not treated with any oil. Treated and untreated fruits were stored at 280±20C and 46%±2 RH for 12 days. Treatments L1P0 and L2P1 oil inhibited postharvest tomato fruit rot for 12 days, whereas L1P2, L0P1, and L1P1 oil and the control showed rot within the range of 86.6% - 100% in 12 days. L1P0 and L2P1 also slowed fruit softening and significantly reduced weight loss, though L1P0 was the most protective. Total soluble solid content of fruit was not affected by both L1P0 and L2P1 throughout storage, but the parameter reduced significantly (p<0.05) in fruits treated with L1P1, L1P2, L0P1 and in control. Reduction in titratable acidity during storage was least in fruits treated with L1P0 followed by L2P1, compared to that in other treatments and the control. This study showed that lemongrass oil applied as surface coating preserved tomato fruit quality in tropical ambient storage conditions for 12 days.

Effect of rabbit urine foliar spray on the yield and post-harvest quality of tomato (Solanum lycopersicum L.)

Of all vegetable crops, tomato occupies the second-largest cultivated land after potato. However, its production is often lamed by insufficient nutrient supply and invasion by insect pests. Unlike inorganic fertilizers and synthetic pesticides commonly used, rabbit urine supplies nutrients to the crops, controls insect pests and has low mammalian toxicity. However, the most suitable rabbit urine foliar spray concentration for tomato production is currently unknown. The experiment was conducted in a randomized complete block design with six treatments and four blocks to evaluate the effect of different concentrations of rabbit urine foliar spray on the yield and post-harvest quality of tomato. The six treatments used include: five concentrations of rabbit urine (100%, 40%, 25%, 18.2% and 0%) and 0.1% Duduthrin 1.75EC. Results indicated that treatment 18.2% rabbit urine registered the highest marketable yield (129.14 t/ha) in trial 1. In trial 2, treatment 25% rabbit urine recorded the highest marketable yield (165.08 t/ha). These two treatments gave the highest marketable yields due to their sufficient nutrient supply, optimal pest control and zero foliage scorching. Unlike fruit firmness and sugar acid ratio, total soluble solids and titratable acidity increased with increase in rabbit urine concentration. Therefore, a rabbit urine foliar spray concentration of 25% optimally improves yield and post-harvest quality of tomato. More research work can be done to determine the effect of spraying intervals of rabbit urine on the yield and post-harvest quality of tomato.

Shelf-life and post-harvest quality of tomato (Lycopesicon esculentum Mill.) varieties to different packaging materials at Mersa, North Wollo, Ethiopia

Tomato (Lycopersicon esculentum Mill.) has a short shelf life at ambient conditions and is a highly perishable crop. Extreme post-harvest losses occur as a result of the wrong packaging materials. However, by employing the right packing materials, tomato varietals can have longer shelf lives. Globally rising fresh tomato demand has forced the development of essential mechanisms, including packaging materials, to improve shelf life. The current study was initiated to evaluate the quality and shelf-life of tomato varieties in response to packaging materials at Mersa, North Wollo, Ethiopia, during 2021 cropping season. Three replications of a completely randomized design were used to test three tomato varieties (Roma VF, Oval red and Woyno) and seven packing materials [closed carton (CC), open carton (OC), closed wooden box (CWB), open wooden box (OWB), perforated polyethylene bag (PPB), non-perforated polyethylene bag (NPPB) and control (C)] at room temperature (20-22°C). According to the findings, there is a significant (P<0.05) interaction effect between packaging materials and varieties on a number of parameters, including physiological weight loss, decay percentage, disease incidence, total soluble solids (TSS), tomato fruit PH, juice color score, overall acceptability, marketability percentage, and shelf life. Non-perforated polyethylene plastic experienced the highest physiological weight losses of 79.88% and 79.63% after 18 days of storage. Roma VF variety showed the greatest weight loss. In addition, PPB showed the lowest decay percentage (20%) and maximum marketability (20%) during the 18th day of storage. At the end of storage, NPPB with Roma VF and Woyno varieties had a substantially (100%) larger decay loss of tomato fruits. NPPB has been linked to the highest disease incidence (20%). Roma VF and Oval red recorded the highest pH tomato fruit’s color and overall acceptability score on PPB. It can, thus, be concluded that packaging of tomato fruits in PPB can extend shelf-life with better-quality of the produce. However, to develop plausible recommendation, the study should be repeated in multi-location with more packaging methods and varieties over seasons.

Effect of Integrated Nutrient Management for Growth, Yield and Post-harvest Quality of Tomato

The cultivated tomato Solanum lycopersicon L., a commercial annual crop that is grown all over the world for local consumption or export purpose. It belongs to the Solanaceae family and has diploid chromosome number (2n= 2X= 24). Application of fertilizers, insecticides and herbicides is crucial for improving productivity per unit area, however excess usage more than that of a recommended dose can lead to issues including environmental contamination (air, water and soil pollution). According to a thorough study, farmers exposed to chemical insecticide spray for a period of 18 months experience impaired vision symptoms like eye stinging or burning (18.42%), dry sore throat (21.05%), blurred vision (23.68%), nose burning (28.9%), shortness of breath and excessive sweating (34.2%), and skin itching or redness (50.0%). The purpose of this brief review article is to explore the function of various organic and inorganic nutrient sources in tomato crop by analysing previous works and studies. Integrated Nutrient Management (INM) is an approach that boosts the agricultural production and safeguards the environment for future generations.

Effect of Ethephon on Ripening and Postharvest Quality of Tomato (Solanum Lycopersicum) During Storage

The experiment was conducted to evaluate the effect of ethephon (2-chloroethyl phosphonic acid) on ripening and postharvest quality of tomato (Solanum lycopersicum). Four concentrations of ethephon viz. 250, 500, 750 and 1000 ppm were applied in the experiment for ripening of tomato under ambient conditions (22±2oC & 80±5% RH) with a control (0 ppm ethephon) in two consecutive years 2012 - 2013. The tomato fruits of ‘Udayan’ variety at breaker stage were harvested from the farmers’. The treated fruits were assessed for ripening percentage and biochemical properties such as total soluble solids (TSS) (%), titratable acidity (%), ascorbic acid content (mg/100g) and total carotenoids (mg/100g). The observations were recorded at 3, 6, 9 and 12 days after storage. The maximum TSS and total carotenoids were found in tomato treated with ethephon concentration @750 - 1000 ppm after 6 days of storage. From the experiment, it was found that ethephon can be applied @750 – 1000 ppm in breaker stage of tomato for uniform ripening within 6 days of storage at ambient temperature. The applied ethephon was estimated as 0.18 - 0.88 ppm at edible stage (6 days of storage), which was lower than the maximum residue limit (MRL) (2 ppm of ethephon) and safe for human consumption.
 Bangladesh J. Agril. Res. 45(3): 303-314, September 2020

Effects of Earthing up and Pruning Systems on Post-Harvest Quality of Tomato (Solanum lycopersicon)

Tomato is a popular and extensively cultivated vegetable among the economically promising commodities in the horticulture sector in Kenya. It provides a wide variety of nutrients with many health-related benefits. This study investigated the effect of integration of pruning and earthing up on postharvest. The experiments were carried out in a split-plot arranged in a randomized complete block design (RCBD) and in CRD for both field and laboratory work respectively. Fruit yield data was taken after each harvest. The results from the analysis of variance for the effect of factors (earthing up and pruning system) and their combined effect showed that there was a significant effect on the average weight loss percentage and total soluble solids in both cultivations. The treatments had a significant effect on the average weight loss percentage, total soluble solids, and fruit firmness in both cultivations. The highest fruit weight loss percentages were recorded from all stem pruning system with no earthing up. The highest fruit firmness (3.41 N mm-1 in cultivation 1 and 3.24 N mm-1 in cultivation 2) was recorded from a single stem pruning system and earthing up to 30 cm. The highest total soluble solids (TSS) percentage 6.09 % was recorded in both cultivations under a single stem pruning system and earthing up to 30 cm. To improve tomato postharvest, farmers are encouraged to consider triple stem pruning system in combination with earthing up to level 30 cm.

Potential of gamma irradiation on postharvest quality of tomato (Solanum lycopersicum L.): a review

Tomato is the most consumed fruit, and an important agricultural product. Losses associated with tomatoes are mainly due to their perishability. Food irradiation using gamma rays is one of the preservation methods which can be used to extend the storage duration while maintaining the sensory quality of tomatoes. This review discussed the potential of gamma irradiation on the postharvest quality aspects of tomatoes through radiation sterilisation. Gamma irradiation has also been proven suitable in delaying the rapid maturity of tomatoes, thus extending their storage life. Doses between 0.5 and 2.5 kGy have been found to maintain the colour, texture, taste, flavour, and overall sensory quality of tomatoes. Gamma irradiation has also been well adopted to control foodborne spoilage and pathogenic microorganisms. Nowadays, many countries allow food irradiation technology as a suitable and cost-effective solution for the problems caused by various types of insects and microorganisms in fresh produce and food products thereof. This review will thus provide updated and in-depth information useful for the producers, manufacturers, and policymakers alike in the adoption of gamma irradiation for tomato preservation.

Effect of different packaging materials on shelf life and postharvest quality of tomato (Lycopersicum esculentum var. Srijana)

Tomatoes, being highly perishable, experience extreme post-harvest losses due to improper packaging materials. Experimentation was done to investigate the effect of different packaging materials on shelf life and quality traits of tomato var. Srijana at the horticulture laboratory of the Institute of Agriculture and Animal Science, Lamjung Campus under a completely randomized design. Seven treatments viz. no packaging (control), unperforated low-density polyethylene (LDPE) bag, perforated (4 holes of 2 mm) LDPE bag, unperforated high-density polyethylene (HDPE) bag, perforated HDPE bag, unperforated non-woven fabric bag, and perforated non-woven fabric bag with 3 replications were used. Tomatoes were evaluated for weight loss, color development, total soluble solids, titratable acidity, pH, and shelf life. Among the treatments, the lowest percentage of weight loss (0.66%) was observed on tomatoes packed in an unperforated HDPE bag, however, it had a higher fungus attack. No packaging group showed rapid shriveling of fruits with the highest percentage of weight loss (14.70%). Although packaging in a non-woven fabric bag was better than control, it showed a higher percentage of weight loss than plastic packaging due to its high permeability to gases and water vapor. The TSS and pH values were found to be higher and TA to be lower in no packaging compared to other packagings. The longest shelf life of tomatoes was observed in perforated LDPE (24 days), followed by HDPE (23 days) whereas the lowest was observed in control (16 days). Overall, the perforated plastic packaging was found best among all treatments with no significant variation among perforated HDPE and perforated LDPE for maintaining qualities of tomatoes and longer shelf life.

Improving postharvest quality of tomato with the application of electric field treatment

Improving postharvest quality of tomato with the application of electric field treatment

Blue LED lighting improves the postharvest quality of tomato (Solanum lycopersicum L. cv. Zahide F1) fruits

Objective: The objective of this study was to investigate the effects of different wavelengths of LED lighting on the postharvest quality of tomatoes (Solanum lycopersicum L. cv. Zahide) during breaker harvest stages..
 Material and Methods: Harvested tomato fruits were placed on 500 g polystyrene foam dishes and wrapped with stretch film. They then were stored in 4±1ºC temperature and 85-90% relative humidity for 42 days under the red (R), blue (B), green (G) and white (W) LED light conditions. The fruits stored in the dark were used as control (C). 
 Results: R and W LED treatments increased hue angle value, yellowness index value, and fruit firmness of tomatoes Blue LED lighting, also decreased electrolyte leakage that indicates delaying senescence. It was also found that blue and red LED lighting delayed fruit decay.
 Conclusion: As a conclusion, it could be satated that the blue LED lighting was found to be more effective than the red, white and green LED light in maintaining the quality of the tomatoes harvested at the breaking stage.

The Quality of Tomato (Solanum Lycopersicum L.) After Pre Storage CaCl2 and Edible Coating Treatment

Tomatoes are a high-value crop all over the world, including Ethiopia. Tomato ripening is highly dependent on ethylene action as a climacteric fruit, making this fruit highly perishable in a short period of time. Pre-storage treatments such as CaCl 2 and edible coatings are essential for preserving fruit quality after harvest and extending shelf life. The purpose of this study was to determine the effect of CaCl 2 and edible coatings on tomato postharvest quality and shelf life. The experiment was set up in the form of a Complete Randomized Design with three replications. The results revealed that both CaCl 2 and edible coatings had a highly significant (p˂0.01) effect on tomato shelf life and quality. Fruits treated with 6% CaCl 2 and coated with aloe Vera gel and beeswax significantly reduced physiological weight loss (PLW), percentage decay, TSS, pH of tomato juice, and ascorbic acid loss during storage, and increased the shelf life of the fruits by 15 days when compared to the control. The combination of treatments (6 percent CaCl 2 with AG and BW coating) resulted in the highest fruit marketability, firmness, and ascorbic acid levels over the storage period. According to the findings of the study, the combination of treatments 6 percent CaCl 2 with aloe Vera gel or bees wax can be recommended for Shanty tomato in terms of shelf life and quality. Keywords: fruit marketability, pre storage, shelf life, tomato, quality DOI: 10.7176/ALST/89-02 Publication date: August 31 st 2021

Perceptions of Smallholder Farmers on Influence of Packaging Postharvest Handling Technology on Quality of Tomatoes in Kisii and Nyamira Counties, Kenya

Reduction of damages, retention of quality of fresh horticultural produce as well as protection against mechanical damages is due to proper packaging. The study aimed at assessing perceptions of smallholder farmers on influence of packaging postharvest handling technologies on quality of tomatoes in the counties of Kisii and Nyamira. The study objective was to assess perceptions of smallholder farmers on influence of postharvest handling methods of packaging on quality of tomatoes in Kisii and Nyamira Counties. The research used descriptive survey research design, multistage sampling technique, purposive sampling to sample counties of Kisii and Nyamira, simple random sampling to sample three sub counties of Kisii Central, Bomachoge Borabu and Borabu Sub Counties. A total of 168 registered smallholder farmers from a target population of 1001 were sampled. Extension officers from Kisii Central, Kenyenya and Borabu were contacted and informed on the purpose of the interview, importance of data in research and the need to respond truthfully to ensure that data collected is reliable. The semi-structured questionnaire was administered to smallholder tomato farmers. Descriptive statistics was analyzed in the form of percentages, means and standard deviation and presented in the form of tables and charts. Inferential statistics was analyzed using Statistical Package for Social Scientists (SPSS) version 20 software. Pearson’s Correlation was used to show the relationships between the variables of dependent and independent with results revealing that methods of packaging had weak positive influence on postharvest quality of tomatoes (r=.286, p<.05). Therefore, necessity to sensitize smallholder farmers on principles of proper packaging of tomato for quality delivery to the market.

Chitosan and Byrsonima crassifolia-based nanostructured coatings: Characterization and effect on tomato preservation during refrigerated storage

Current concerns about the use of synthetic pesticides for preserving horticultural commodities have triggered the search for environmentally friendly packaging. In this regard, this study evaluated the effect of chitosan nanoparticle and chitosan-Byrsonima crassifolia nanoparticle coatings on the postharvest quality of tomato and on the incidence of Pectobacterium carotovorum after 19 days of storage. Thickness and swelling properties as well as the quality and physiological variables, and antimicrobial activity were determined. From the results, confocal laser scanning micrographs showed the interaction between the tomato and the coating containing the rhodamine-labeled chitosan nanoparticles. Changes in chroma and hue angle values as well as for firmness, with an increase in ascorbic acid content and lower CFU (colony-forming units) for the tomatoes coated with chitosan nanoparticles at a concentration of 30% were observed. The weight loss values were less than 13%. There was a decrease in CO2 and ethylene production at the end of the storage period. Chitosan-based nanostructured coating represents an alternative for preserving tomatoes against P. carotovorum.

Growth, yield and postharvest quality of tomato (Solanum lycopersicum Mill.) as influenced by different rates of nitrogen fertilizer

There is no available information on optimal nitrogen (N) fertiliser rates to maximise tomato production in the Philippines hence excessive N application is a problem. This research was conducted to determine the optimum rate of N to enhance production of different tomato cultivars. The experiment was a randomized complete block factorial design evaluating a range of N rates (72.8, 122.8, 172.8, 222.8, 272.8 and 322.8 kg N ha-1) in combination with two cultivars ('Harabas Rescuer 746' and 'AVTO1173') and replicated four times. On the 2nd crop, an N rate of 222.8 kg ha-1 produced the highest total plant dry matter yield (176 g plant-1), the largest and heaviest fruits (mean 49.6 g) and the lowest weight loss. The highest fruit yields were also recorded at an N rate of 222.8 kg ha-1 for the first (14.4 t ha-1) and second (28.1 t ha-1) crops. 'AVTO1173' had the earliest flowering, a 47% higher dry matter value and produced the largest diameter fruit (5.33 cm in first crop and 4.9 cm in the second crop). 'AVTO1173' was less susceptible to diseases compared with 'Harabas Rescuer 746' and had less shrivelling in the 1st cropping cycle. It is recommended that nitrogen fertilization at 222.8 kg N ha-1 should be used for producing high yields and good tomato fruit quality. © 2021 International Society for Horticultural Science. All rights reserved.

Improvement in storage quality of postharvest tomato fruits by nitroxyl liposomes treatment

Nitroxyl (HNO) has attracted much attention due to its unique biological activity. To investigate the preservation effect of HNO on fruits, a nitroxyl liposome based on 1-nitrosocyclohexyl acetate was prepared and characterized by infrared spectroscopy and transmission electron microscopy. The optimal preparation conditions were explored, and then HNO liposomes were prepared under the optimal conditions to study the effect of HNO liposomes on postharvest quality of tomatoes. The tomato fruits were treated with different concentrations (0, 5, 10, 15 and 20 μmol L-1) of HNO liposomes and stored at room temperature. The results indicated that treatment with HNO liposomes can more effectively delay the browning and slow down the decrease in lightness of tomatoes. Additionally, HNO liposomes can reduce the activity of PPO and POD, inhibit the increase of MDA and total phenol content. These results suggest that treatment with HNO liposomes can effectively preserve the quality of tomatoes.

Effect of pre-harvest calcium silicate on post-harvest quality of tomatoes

The present work evaluated the influence of calcium silicate on the polygalacturonase enzyme activity, respiration, ethylene, and the physicochemical characteristics on the post-harvest quality of two tomato hybrids. The experimental design was of randomized blocks, with four repetitions in protected cultivation environment. The treatments were distributed in a 2 x 5 factorial scheme, corresponding to the hybrids (Ivety and Natalia) and five doses of calcium silicate (0, 150, 300, 450 and 600 kg ha-1), which were applied on the same day as the pots were filled. Evaluations were carried out on the fruits, namely: ethylene production, fruit respiration, firmness, number of loculus, polygalacturonase activity, total carotenoids, lycopene, phenolic compounds, soluble solids content, pH, titratable acidity and ascorbic acid content. The application of calcium silicate provided the reduction of ethylene production and fruit respiration. Natalia hybrid showed low polygalacturonase activity, this difference being due to genetic variabilityThe increase of calcium silicate doses provided the reduction of polygalacturonase enzyme concentration due to its constitution in the cell wall. The concentrations of lycopene, phenolic compounds, soluble solids, pH, titratable acidity and ascorbic acid in the fruits increased in response to the increasing doses of calcium silicate for 'Ivety'. Hybrids present distinct behaviors on the influence of the fertilization of tomatoes with calcium silicate, which can increase the post-harvest conservation and improve the physical-chemical characteristics of tomato fruits.

Effect of UV-C Hormesis in Regulating Anthracnose Disease and Postharvest Quality of Tomato

Purpose : Anthracnose disease caused by Colletotrichum coccodes is a significant postharvest disease in tomatoes. Although there are negative impacts of fungicides usage on fresh produce, at present, it is the most common method of eliminating diseases. UV-C hormesis was used in this study as a trending non-chemical postharvest treatment.Research Method : Tomato varieties ‘Thilina’ and ‘Roma’ were used to check the efficacy of UV-C treatments. Five different UV-C dosages (0, 1, 2, 3, 4, 5 kJ/m2) were applied to pure cultures of C. coccodes (254 nm at a distance of 15 cm). The selected dosages (3.0 and 4.0 kJ/m2) were tested on the effect of anthracnose disease development in vivo and the change in postharvest quality parameters (weight loss, firmness, shelf life, antioxidant and total phenolic content). Antifungal activity of the peel was investigated using Cladosporium bioassay. Findings : Weight loss of treated ‘Thilina’ variety has significantly increased (P < 0.05). The antioxidant activity and the total phenolic content of both treated varieties have increased. The firmness has significantly retained in treated ‘Thilina’ variety. Further, the shelf life has significantly extended in both treated varieties by approx. 2 folds compared to the non-treated control. All tested tomato samples indicated the presence of antifungal compounds in their peels. Therefore, to suppress anthracnose disease 4.0 kJ/m2, and 3.0 and 4.0 kJ/m2 are the most suitable UV-C dosage for ‘Thilina’ and ‘Roma’ respectively.Research Limitations : This research is based on the available tomato cultivars in the market.Originality / Value : This is a non-chemical treatment which could be utilized by farmers in future, to control postharvest anthracnose in tomatoes.Purpose : Anthracnose disease caused by Colletotrichum coccodes is a significant postharvest disease in tomatoes. Although there are negative impacts of fungicides usage on fresh produce, at present, it is the most common method of eliminating diseases. UV-C hormesis was used in this study as a trending non-chemical postharvest treatment.Research Method : Tomato varieties ‘Thilina’ and ‘Roma’ were used to check the efficacy of UV-C treatments. Five different UV-C dosages (0, 1, 2, 3, 4, 5 kJ/m2) were applied to pure cultures of C. coccodes (254 nm at a distance of 15 cm). The selected dosages (3.0 and 4.0 kJ/m2) were tested on the effect of anthracnose disease development in vivo and the change in postharvest quality parameters (weight loss, firmness, shelf life, antioxidant and total phenolic content). Antifungal activity of the peel was investigated using Cladosporium bioassay. Findings : Weight loss of treated ‘Thilina’ variety has significantly increased (P < 0.05). The antioxidant activity and the total phenolic content of both treated varieties have increased. The firmness has significantly retained in treated ‘Thilina’ variety. Further, the shelf life has significantly extended in both treated varieties by approx. 2 folds compared to the non-treated control. All tested tomato samples indicated the presence of antifungal compounds in their peels. Therefore, to suppress anthracnose disease 4.0 kJ/m2, and 3.0 and 4.0 kJ/m2 are the most suitable UV-C dosage for ‘Thilina’ and ‘Roma’ respectively.Research Limitations : This research is based on the available tomato cultivars in the market.Originality / Value : This is a non-chemical treatment which could be utilized by farmers in future, to control postharvest anthracnose in tomatoes.

Effect of harvesting stages and postharvest treatments on shelf life and quality of tomato (Lycoper-sicon esculentum Mill. var. Pearson) stored under ZECC condition

Tomato (Lycopersicon esculentum Mill) is one of the important commercial high value crops of Afghanistan. Among the different local varieties grown in Afghanistan, the “Pearson” variety is most popular because of its good commercial value due to its uniform globe shape and medium to large size. The study is conducted to understand the effects of different harvesting stages and postharvest treatments on the shelf life and postharvest quality of tomatoes (Pearson variety) stored under the Pusa Zero Energy Cool Chamber (ZECC) at the research farm of Agriculture Faculty, Kabul University. This is the first time that ZECC is introduced in Afghanistan for enhancing fruit shelf life. The standard dimension ZECC was built with 165 x 115 x 67.6 cm dimensions. After harvesting tomatoes at different maturity stages (Turning, Pink, and Light red color stages), fruits were precooled, graded, and treated with different concentrations of CaCl2 and mint leaf extract solutions. Thereafter, the tomatoes were placed in plastic baskets and stored in the Zero Energy Cool Chamber. During storage period, Total Soluble Solids (TSS, 0brix), pH, firmness (gr cm-2), shelf life, pericarp thickness (mm), fruit volume (cc), and fruit density were recorded. Two factorial CRD design was considered with harvesting stages as the first factor and postharvest treatments as the second factor. The data revealed that the shelf life of tomatoes was extended up to 29 days under T2 (turning color fruits treated with 6% CaCl2) and followed by T8 (turning color fruits treated with 6% CaCl2 + 6% mint ...

Postharvest quality of tomato as affected by nitrogen and sulfur interaction

Nitrogen (N) and sulfur (S) are nutrients that, in addition to influencing plant growth and production, interfere with processes related to postharvest fruit quality. In the present study, N x S interaction was evaluated in the postharvest quality of tomato (Solanum lycopersicum L.). The experiment was conducted in a greenhouse using 5 dm3 capacity vessels containing a 0-20 cm layer of a dystropherric Red Latosol. A 5 x 3 factorial design was used, with combinations of five doses of N (0, 100, 200, 300 and 400 mg dm-3) and three doses of S (0, 60 and 120 mg dm-3) distributed in a completely randomized design, with four repetitions. After harvest, the attributes of fruit quality were evaluated: firmness, pH, soluble solids (SS), titratable acidity (AT), soluble solids ratio and titratable acidity (SS / AT), vitamin C, lycopene and beta-carotene. An increase in firmness was observed, as well as the content of soluble solids, titratable acidity and the SS / AT ratio of the fruits as a result of the interaction N x S. However, this interaction favoured the reduction of the contents of vitamin C, lycopene and beta-carotene, and the quality characteristics of tomato fruit in relation to the recommended values. Only the increasing doses of N favoured a higher pH in the tomato fruits.

Agronomic yield and quality of industrial tomatoes under NPK doses

ABSTRACT High doses of nitrogen, phosphorus and potassium in irrigated systems may lead to an increase in the productivity of industrial tomatoes, but may also alter the final quality of the fruits. The objective of this was to evaluate the agronomic yield and post-harvest quality of industrial tomatoes, under NPK doses for climatic conditions of Northern Minas Gerais state, Brazil. The study was conducted in the city of Jaíba, MG, Brazil, in randomized block design with four repetitions in a 3 x 3 factorial scheme, consisting of three doses of N (90, 135 and 180 kg ha-1), of P (270, 405 and 540 kg ha-1) and of K (225, 337 and 450 kg ha-1), corresponding to 50, 75 and 100% of the fertilization recommendation; and three tomato hybrids: BRS Sena, Heinz 9553 and BHN 0574. The following variables were evaluated: number of bunches, number and weight of fruits, productivity and fertilizer efficiency index; besides the physico-chemical characteristics: firmness, soluble solids concentration, pH and pulp industrial yield. The hybrid Heinz 9553 showed higher weight, number of fruits, productivity and industrial yield at doses of 75 and 100% of NPK recommendation. The fertilizer doses did not interfere on the soluble solids, pH and fruit firmness of the three hybrids. The hybrid BRS Sena was not influenced by the increase of NPK and there was lower weight, number of fruits, productivity and fertilization efficiency. The hybrid BHN and Heinz hybrids can be indicated for cultivation at doses of 100 and 75% of NPK recommendation, because they promote higher agronomic yield and do not alter the post-harvest quality of the tomatoes.