Seedlings Of Cv Research Articles

Adaptation reactions of common wheat (Triticum aestivum L.) and emmer (T. dicoccum Schrank ex Schübl.) seedlings under osmotic stress and treatment with metal nanoparticles

Aim. To study the adaptive reactions of common wheat (Triticum aestivum L.) and emmer (T. dicoccum Schrank ex Schübl.) seedlings using the parameters of oxidative homeostasis under polyethylene glycol (PEG)-induced osmotic stress and metal (Fe, Cu, Mn, Zn) mixture nanoparticles treatment. Methods. Biochemical assays: spectrophotometric measurements of the activity of antioxidant enzymes (SOD, CAT), the content of proline and products of lipid peroxidation; mathematical statistics. Results. The state of oxidative homeostasis of common wheat (cv. Favorytka, cv. Trypilska) and emmer (cv. Holikovska) seedlings under PEG-induced osmotic stress conditions was investigated and analyzed. The development of lipid peroxidation processes under stress conditions was observed only in the cv. Trypilska seedlings. It was established that proline content in common wheat seedlings of both cultivars under stress had signifi cant (10 : 1) predominance in roots, while in roots and shoots of emmer seedlings proline content increased equally. SOD activity in the leaves of the studied cultivars under stress conditions was not changed. At the same time, an increase of SOD activity by 30 % under osmotic stress was shown in the roots of common wheat of cv. Favorytka, while it decreased by 25 % in the roots of cv. Trypilska. It was established that CAT activity in the roots of both cultivars of common wheat decreased by 25 and 38 %, respectively, whereas in emmer of cv. Holikovska this parameter increased by 35 % under osmotic stress. Presowing treatment using a colloidal solution of a mixture of biogenic metal nanoparticles contributed to the induction of SOD activity in the roots of cv. Favorytka, CAT activity in the leaves of cv. Trypilska, and CAT activity in the roots and leaves of cv. Holikovska compared to non-treated plants. It should be noted that the treatment of plants with metal nanoparticles promoted the restoration of CAT activity in the roots under osmotic stress conditions to the level of the control plants in both wheat varieties. Conclusions. It was established that osmotic stress provoked the development of oxidative processes and inhibition of the activities of antioxidant enzymes, in particular, SOD and CAT, in the seedling roots of common wheat cultivars. It was shown that emmer wheat seedlings of cv. Holikovska can maintain redox homeostasis and avoid oxidative damage under osmotic stress conditions. It was found that the seedlings of common wheat and emmer demonstrated different strategies of osmotic regulation under osmotic stress, which is confi rmed, in particular, at the level of proline accumulation. It was shown that the application of colloidal solutions of metal nanoparticles induced an antioxidant protection system and reduced the oxidative processes, which are inevitable effects of drought. The obtained results indicate that common wheat cultivars are more susceptible to drought compared to emmer wheat of cv. Holikovska.

Growth of seedlings in banana plant cv. Prata Catarina micropropagated in organic substrates

In commercial bananas there is an increasing increase for seedlings of high genetic quality and free of pathogens; thus, the use of micropropagation has been increasingly encouraged for the production of seedlings. However, the success of establishing these seedlings in the environment depends on several factors, in which, the substrate has a relevant role. The objective of this study was to evaluate the growth of micropropagated banana seedlings under the influence of different formulations of substrates based on soil, bovine manure and vegetable ash for organic production system. The experiment was carried out on a certified rural property under an organic production system in the municipality of Palmácia (CE). The experimental design used was completely randomized, with four replications. The substrates were used in a ratio of 2:1, always two parts of soil for one of substrate, which was used: soil (ravine soil), organic compost (bovine manure + vegetal remains), bovine manure and vegetable ash (from sugar cane mill). The test was conducted in full sun and without the aid of irrigation, as the experiment coincided with the rainy season in the region. At 68 days after planting (DAP), growth analyzes were carried out: plant height, diameter of the pseudostem, number of leaves, length of roots, fresh and dry mass of aerial part and roots. The best substrates for the growth of micropropagated banana seedlings cv. Prata Catarina were mixtures of soil + organic compost and soil + manure.

Effect of spraying with Tecamin Algae and NPK fertilizer on the growth of pomegranate (Punica granatum L.) seedlings cv. California wonderful

This study was carried out in the lath house of the Department of Horticulture and Landscape at the Faculty of Agriculture, University of Kufa for the period from 1st March to 1st December, 2015. The experiment was conducted on six months old pomegranate seedlings (Wonderful cultivar) in order to study the effect of spraying with Tecamin Algae with four concentrations (1, 2, 3 and 4) ml.l−1 and NPK fertilizer at 100, 200, 300 and 400 kg.ha−1. The treatments were examined separately and overlapping. The results showed that spraying the seedlings with the treatments and their interactions caused a significant increase in seedling length and its diameter, number of leaves, leaf area, fresh and dry weight of vegetative shoot, and total chlorophyll of leaves. The treatment of interference between the marine algae extract (4 ml.l−1) and NPK fertilizer (400 kg.ha−1) was superior by obtaining the highest values of all traits compared with control treatment. It can be concluded from this study that a balanced fertilization management that combines the use of chemical, organic or bio-fertilizers must be developed and evaluated with different plants and under different cultivation system.

Performance of agricultural substrates in the production of lettuce seedlings (Lactuca sativa L.)

The production of seedlings for transplanting is one of the most important stage to successful lettuce cultivation. Among the techniques practiced to obtain seedlings of vegetables, stands out using agricultural substrates associated with the cultivation trays. The experimental setup design was in completely randomized with 5 treatments and 6 repetitions.The experiment was carried out in a greenhouse, where were evaluated five commercial substrates (TropstratoHT®, Vivatto Slim Plus®, Tecnomax® , Holambra HS® and Bianchi Power) for the development of lettuce seedlings cv. Lucy Brown. Analyzes were performed to quantify the physical and chemical characteristics of the substrate. It was evaluated Fresh mass of shoots and roots, total fresh mass, dry mass of shoots and roots, total dry mass, stalk diameter, leaf area and leaf number. The results showed that among evaluated substrates, Bianchi Power ® showed be more efficient to seedling lettuce production by influence on the growth and development

Control of late blight in organic farming with low copper dosages or natural products as alternatives to copper

The aim of this paper is to explore appropriate alternative products to copper for the control of late blight disease in organic farming. In fact, due to its persistence and toxicity, copper appears incompatible with organic farming’s objectives of environmentally friendly farming. The effect of plant extracts, inorganic products, microorganisms and chitosan were investigated in vitro and in a greenhouse pot trial. The in vitro tests consisted of evaluating both the development of oomycete colonies on an agar medium supplemented with the tested products at various concentrations and the inhibiting effect of products on sporangial germination. The greenhouse trial was carried out on 5-week-old tomato seedlings cv. Cuore di Bue di Albenga. Tomato seedlings were transplanted into pots containing pasteurized soil and were then treated with the investigated products. After 24 h, they were inoculated with a sporangial suspension of Phytophthora infestans. The disease severity for each pot was estimated. The results showed a remarkable inhibitory effect on hyphae growth and sporangia germination of the tested products. Under greenhouse experiments, all treatments significantly reduced late blight in comparison with water control plants. The best results were obtained with the formulation containing copper at low doses and leaf licorice extract. In conclusion, the results of this study show that it is possible to reduce the dependency on copper in crop protection by using low copper dosages or natural products.

Foliar application of betaine improves water-deficit stress tolerance in barley (Hordeum vulgare L.)

A hydroponic experiment was carried out to study the alleviating effects of exogenous betaine on drought stress in barley seedlings (Hordeum vulgare L.) cv. ZJU9. Results showed that foliar applications of 500 µM betaine ameliorated drought-induced reductions in plant height, root length and root dry weight and improved chlorophyll contents and photosynthesis parameters, compared with seedlings given a drought alone treatment. In addition, exogenous betaine significantly increased root and leaf SOD, POD, APX and root CAT activities (cf. 15.5%/19.8%, 13.5%/7.9%, 10.0%/31.9%, 10.45%/11.3% higher than drought alone treatment), markedly reduced Na+ concentrations and elevated the K+/Na+ ratio in both shoots and roots by 39.0, 38.7, 50.7 and 42.6%. Also, betaine ameliorated drought-induced damage to leaf and root ultrastructure, effectively improving the stability and integrity of the nuclear membrane of root meristem cells and increased cell viability in roots tips. The results suggest that betaine alleviates drought-induced oxidative damage in plants via stimulating antioxidative enzyme activities and K uptake, and helps to maintain stability and integrity of the sub-cellular structure under drought stress.

Evaluation of copper alternative products to control grape downy mildew in organic farming

The aim of this work was to investigate the efficacy of copper alternative products of natural origin against Plasmopara viticola to reduce or replace the use of copper in organic farming. The identification of new active and sustainable substances is in fact of priority importance because of the environmental impact of copper. The activity of the products was investigated in laboratory and greenhouse conditions. The laboratory tests included the evaluation of the effect of products on mycelial growth, using artificially inoculated leaf disks, and on sporangial germination. The greenhouse experiments were carried out on grape seedlings cv. Malvasia di Candia treated with products and inoculated, after 24 h, with sporangial suspension of P. viticola. The results both of laboratory and greenhouse tests showed inhibitory activity performed by several botanicals (licorice leaf extract, Yucca schidigera extract), by ALD1901 product, a derivative from Saccharomyces cerevisiae yeast, by Vacciplant formulation containing laminarin and by inorganic products as potassium hydrogen carbonate and MenoRame formulation based on micro-doses of copper and zeolites. The identification of sustainable approaches to manage grape downy mildew is very important to enhance the quality of organic production.

Mathematical Modeling for Leaf Area Estimation From Papaya Seedlings ‘Golden THB’

The aim of this study was to select the most suitable model for leaf area estimation from papaya seedlings cv. ‘Golden THB’ using linear dimensions of leaves with unilobular and trilobular morphology. It was used leaves of 60 seedlings with 30 days after sowing produced in nursery of the Fazenda Santa Teresinha which belongs to company Caliman Agrícola S.A., in the municipality of Linhares, state of Espírito Santo, in March 2016. The measurement of the length (L) was performed along the midrib, the maximum width (W) of the leaf blade, the product of the length by the width (LW) and the observed leaf area (OLA). From these results, first degree and power linear regression models was adjusted. From the proposed regression models, the validation was performed with a leaves sample of 60 seedlings produced in June 2016, obtaining, thus, the estimated leaf area (ELA). The following criteria were used to choose the best model: the highest coefficient of determination (R2), the values do not significant of the comparison of means of OLA and ELA and values of MAE and RMSE closer to zero. The leaf area estimation from papaya seedlings cv. ‘Golden THB’ can be represented through equation ELA = -0.402619 + 0.612525(LW) for trilobular leaves and through equation ELA = 0.623355 + 0.610552(LW) for unilobular leaves.

Salt stress and exogenous application of hydrogen peroxide on photosynthetic parameters of soursop

ABSTRACT This study aimed to evaluate the gas exchanges and photosynthetic pigments of soursop seedlings cv. ‘Morada Nova’ irrigated with saline waters and subjected to exogenous application of hydrogen peroxide by seed soaking and foliar spraying. The study was carried out using plastic bags under greenhouse conditions at the Center of Technology and Natural Resources of the Federal University of Campina Grande, PB, Brazil, using a eutrophic Regolithic Neosol of sandy loam texture. Treatments were arranged in a randomized block design, in 5 x 5 factorial scheme, which consisted of five levels of electrical conductivity – ECw (0.7; 1.4; 2.1; 2.8 and 3.5 dS m-1) of irrigation water and five concentrations of hydrogen peroxide - H2O2 (0, 25, 50, 75 and 100 µM), with four replicates and three plants per plot. As the salt stress increased, there were reductions in internal CO2 concentration, instantaneous carboxylation efficiency and water use efficiency, and instantaneous carboxylation efficiency was the most sensitive variable. Hydrogen peroxide at concentrations of 25 and 50 µM attenuated the deleterious effects of water salinity on stomatal conductance, CO2 assimilation rate and chlorophyll a content, and the concentration of 25 µM was the most efficient. The content of chlorophyll b and carotenoids of soursop cv. ‘Morada Nova’ had the deleterious effects caused by the salinity of irrigation water mitigated by the exogenous application of hydrogen peroxide in the concentration of 25 μM.

Production of tomato seedlings Santa Cruz cv. Kadain using different substrates

The tomato crop is considered of great socio-economic importance in the world, feeding millions of people daily. This crop is considered strategic because its production is diverse in the world, being produced by large agro-industries, moving a rich productive chain. This work aimed to evaluate the production of tomato seedlings as function of different substrates, and to comprehend the interrelation of characteristics through linear associations. The experimental design was randomized blocks, using one tomato cultivar, Santa Cruz Kada, in 32 repetitions for each treatment. The treatments consisted of several substrates such as carbonized rice husk, grape husk (S10), coconut fiber, and commercial substrate (Bioplant®). The experiment was carried out in a greenhouse using pots. The characters measured 25 days after sowing were: stem diameter, number of leaves, shoot length, root length, green mass of root, green mass of shoot, dry mass of shoot, and dry mass of root. The analysis of variance was performed and the characters that presented significance were compared by the Duncan test at 5% of probability. Subsequently, Pearson’s linear correlation was individually performed for each substrate. The results showed that commercial (Bioplant®) and grape skin substrates were the most suitable for production of tomato seedlings cv. Santa Cruz Kada. The characters of stem diameter, number of leaves, shoot length, green mass of root and green mass of shoot revealed significant correlations; however they differently behaved in the substrates.

Response of root-knot nematode Meloidogyne javanica to ozone

ABSTRACT Root-knot nematode, Meloidogyne javanica is a major causal agent of plant diseases on summer crops in fields and greenhouses. In order to reduce environmental concerns, compounds having pesticidal capacity with insignificant residue can be a good alternative to synthetic pesticides. This study was undertaken to investigate the nematicidal capability of ozone under Petri dish (in vitro) and pot (in the rhizosphere of tomato seedlings cv. Super Chief) conditions. The experiments were conducted based on Completely Randomized Design in four replicates with two antimicrobial materials, Cadusafos (0.5, 1.0, 1.5, 2.0, 2.5 and 3 g kg-1 soil) and ozone (0.05, 0.1, 0.2, 0.4, 0.8 and 1.6 g kg-1 soil). Results confirmed the significant in vitro controlling effect of ozone on nematode egg (85%, in 0.4 g kg-1 soil) and second stage juvenile (72%, in 0.4 g kg-1 soil) populations. Also a toxic effect of ozone was observed on the nematode pathogenicity, i.e. galling (83%, in 0.4 g kg-1 soil), on tomato root in pot assays. Plant morphological traits (i.e. root fresh weight, foliage fresh weight, and stem length) were not significantly affected by ozone. Therefore, taking into account the principles of safety in the application of ozone, this material can be suggested as an alternative nematicide, at least at limited and controlled condition.

Enhanced Tolerance of Chinese Cabbage Seedlings Mediated by Bacillus aryabhattai H26-2 and B. siamensis H30-3 against High Temperature Stress and Fungal Infections.

Two rhizobacteria Bacillus aryabhattai H26-2 and B. siamensis H30-3 were evaluated whether they are involved in stress tolerance against drought and high temperature as well as fungal infections in Chinese cabbage plants. Chinese cabbage seedlings cv. Ryeokgwang (spring cultivar) has shown better growth compared to cv. Buram-3-ho (autumn cultivar) under high temperature conditions in a greenhouse, whilst there was no difference in drought stress tolerance of the two cultivars. In vitro growth of B. aryabhattai H26-2 and B. siamensis H30-3 were differentially regulated under PEG 6000-induced drought stress at different growing temperatures (30, 40 and 50°C). Pretreatment with B. aryabhattai H26-2 and B. siamensis H30-3 enhanced the tolerance of Chinese cabbage seedlings to high temperature, but not to drought stress. It turns out that only B. siamensis H30-3 showed in vitro antifungal activities and in planta crop protection against two fungal pathogens Alternaria brassicicola and Colletotrichum higginsianum causing black spots and anthracnose on Chinese cabbage plants cv. Ryeokgwang, respectively. B. siamensis H30-3 brings several genes involved in production of cyclic lipopeptides in its genome and secreted hydrolytic enzymes like chitinase, protease and cellulase. B. siamensis H30-3 was found to produce siderophore, a high affinity iron-chelating compound. Expressions of BrChi1 and BrGST1 genes were up-regulated in Chinese cabbage leaves by B. siamensis H30-3. These findings suggest that integration of B. aryabhattai H26-2 and B. siamensis H30-3 in Chinese cabbage production system may increase productivity through improved plant growth under high temperature and crop protection against fungal pathogens.

ADIÇÃO DE COMPOSTOS ORGÂNICOS EM SUBSTRATO COMERCIAL PARA PRODUÇÃO DE MUDAS DE TOMATE

This study aimed to evaluate the formation of tomato seedlings cv. Santa Cruz Kada(Paulista)with the merger in the commercial substrate of organic compounds in different proportions. The design was a completely randomized design, with four replications. The treatments were formed from the combination of the mixture of commercial substratewith castor cake, cattle manure and aviary bed. Regarding the treatments, which presented averages significantly superior to the other was the mixture of 25% cattle manure and 75% commercial substratefor the production of tomato seedlings.

Evaluating crude extracts of Monsonia burkeana and Moringa oleifera against Fusarium wilt of tomato

ABSTRACTFusarium wilt is one of the major soil-borne diseases of tomato crop globally. The study aimed to evaluate the efficacy of medicinal plants in the control of Fusarium wilt in tomato. Methanolic extracts of Monsonia burkena and Moringa oleifera were assessed in vitro and under greenhouse conditions. The in vitro experiments evaluated the effect of both extracts on Fusarium oxysporum f. sp lycopersici growth and response to varying concentrations. In greenhouse experiment, tomato seedlings cv. HTX14 were inoculated with conidial suspension of F. oxysporum and transplanted into pasteurised growth media amended with plant extract. Seedlings were treated with aqueous extracts at varying concentrations with an interval of 7 days between applications. Control treatments were treated with sterile distilled water. Both plant extracts significantly reduced pathogen growth in vitro and reduced wilt severity under greenhouse conditions. The highest mycelial growth suppression was observed in Mon. burkeana treatments. Under greenhouse conditions, both plant extracts significantly (P ≤ 0.05) reduced Fusarium wilt severity and had a positive effect on plant growth parameters. A significant increase in soil-pH was also recorded in extract treated soil resulting in reduction in disease severity. The results further provide new scientific information on how their effect on soil pH can be beneficial in the control of Fusarium wilt.

Variety-specific nutrient acquisition and dehydration-induced proteomic landscape of grasspea (Lathyrus sativus L.)

Grasspea, a stress-resilient pulse crop, has largely remained outside the realm of phytochemical and functional genomics analyses despite its high nutritional significance. To unravel the intervarietal variability in nutrient acquisition of grasspea, we conducted a series of physicochemical experiments using two cultivated varieties, LP-24 and Prateek. The analyses revealed high percentage of starch, cellulose, peroxides, carotenoids, phytic acid and minerals in cv. LP-24, whereas large amounts of protein, soluble carbohydrates and antioxidants in Prateek. To dissect the mechanism of stress tolerance, 3-week-old seedlings of cv. LP-24 and Prateek were afflicted with dehydration for a period of 144 h. The physicochemical indices indicated better adaptation in cv. LP-24, with high abundance of proline, phenolics and flavonoids. Dehydration-responsive proteome landscape of cv. LP-24 revealed 152 proteins with variance at a statistically 94% significance level. The comparative proteomics analysis led to the identification of 120 dehydration-responsive proteins (DRPs), most of which were associated with carbohydrate metabolism, amino acid synthesis, antioxidant reactions and cell defense. We report, for the first time, the dehydration-induced proteome landscape of grasspea, whose genome is yet to be sequenced. The results provide unique insights into variety-specific nutrient acquisition attributes and dehydration-tolerance of grasspea. Biological significanceGrasspea is a great source of protein and antioxidants with nitrogen fixing ability, besides its tolerance to multivariate environmental stress as compared to major legume species. This represents the first report on nutrient profile and health-promoting attributes of grasspea. The cultivars under study are nutritionally enriched that possess high protein, amino acids and health-promoting factors and may therefore be projected as a vital part of a healthy diet. Grasspea is known for its hardy nature, water-use efficiency and efficacy as a stress-tolerant pulse. Further, this study portrays the dehydration-responsive proteomic landscape of grasspea. The proteomics analyses provide crucial insights into the dehydration response, presumably orchestrated by proteins belonging to an array of functional classes including photosynthesis, protein and RNA metabolism, protein folding, antioxidant enzymes and defense. The interplay of the differentially regulated proteins might aid in reinforcing the mechanisms of dehydration avoidance and/or tolerance.

Pó-de-basalto no desenvolvimento de plantas de alface e na dinâmica populacional de insetos

The aim of this work was to evaluate effect of the application of basalt powders from three different origins via soil (incorporation) and aerial (spraying) application in the performance of lettuce plants and in the population dynamics of phytophagous insects, respectively. Lettuce seedlings cv. Veronica at 8 days after emergence were transplanted to raised beds after the incorporation of the basalt powders. The effects on plant development were evaluated 50 days after transplantation and the parameters assessed were: plant height, growth of root system, dry mass, insertion diameter, volume of the root system and chlorophyll and carotenoid contents. Insect population dynamics was performed after the application of 100 g of basalt powder diluted in two liters of water (2 L ha) through four sprayings with intervals of 10 days between each. Sampling was performed daily and the insects collected were separated and identified. There was a significant increase in the variables plant height, growth of root system and dry mass in the treatments with the incorporation of basalt powder in the soil when compared to the control treatment. There was also a significant increase of 36% and 20% in the chlorophyll and carotenoid contents in lettuce leaves, respectively. There was no significant difference in the volume of the root system and insertion diameter between the treatments. The aerial spraying on lettuce plants with different basalt powders directly influenced the insect population dynamics with a significant decrease in the number of insects collected in all treatments.

Pó-de-basalto no desenvolvimento de plantas de alface e na dinâmica populacional de insetos

The aim of this work was to evaluate effect of the application of basalt powders from three different origins via soil (incorporation) and aerial (spraying) application in the performance of lettuce plants and in the population dynamics of phytophagous insects, respectively. Lettuce seedlings cv. Verônica at 8 days after emergence were transplanted to raised beds after the incorporation of the basalt powders. The effects on plant development were evaluated 50 days after transplantation and the parameters assessed were: plant height, growth of root system, dry mass, insertion diameter, volume of the root system and chlorophyll and carotenoid contents. Insect population dynamics was performed after the application of 100 g of basalt powder diluted in two liters of water (2 L ha) through four sprayings with intervals of 10 days between each. Sampling was performed daily and the insects collected were separated and identified. There was a significant increase in the variables plant height, growth of root system and dry mass in the treatments with the incorporation of basalt powder in the soil when compared to the control treatment. There was also a significant increase of 36% and 20% in the chlorophyll and carotenoid contents in lettuce leaves, respectively. There was no significant difference in the volume of the root system and insertion diameter between the treatments. The aerial spraying on lettuce plants with different basalt powders directly influenced the insect population dynamics with a significant decrease in the number of insects collected in all treatments.

Impact of Bio-Fertilizer EM and Plants Dried Leaf Powders of Water Hyacinth or Turmeric on Tomato Plants Infected by Meloidogyne incognita at Greenhouse Conditions.

A pot assessment was conducted to verify the impact of bio-fertilizer EM and dried powder of water hyacinth plant (Eichhornia Crassipes) or turmeric plant (Curcuma longa) either or integrated applications on plant reaction of tomato seedlings cv. 888 F1 infected by M. incognita at greenhouse conditions. It is remarkable to detect that the experienced binary applications accomplished better results than single ones did. Evidently, data showed that all tested components enhanced tested plant criteria and also diminished nematode parameters. The bio-fertilizer EM application plus dry-leaf powder of water hyacinth plant mixed with oxamyl at triple doses each showed the maximum value of whole plant length (73.0%), whole plant fresh weights (231.8%), shoot dried weight (246.8%), leaves number (126.52%) and branches number (41.51%), respectively. In the meantime, the tetra application of (bio-fertilizer EM + turmeric + water hyacinth +oxamyl) accomplished the maximum decrease percentage in total nematode final density, galls and egg-masses number with values of 97.4, 86.5 and 91.5%, correspondingly. It was obvious that nitrogen, phosphorus, potassium concentration, chlorophyll and phenol contents were apparently reduced by nematode infectivity by deferent degrees. All tested applications showed significant increase percentages of in nitrogen, phosphorus, potassium concentration, chlorophyll and phenol contents greater than those of nematode alone.

Emergence and early development of tomato seedlings cv. santa clara in alternative substrates

Emergence and early development of tomato seedlings cv. santa clara in alternative substrates

Growth and quality of soursop (Annona muricata, L.) seedlings under saline stress and hydrogen peroxide (H2O2)

This study aimed to evaluate growth and quality of soursop seedlings cv. Morada Nova, as a function of saline water irrigation and exogenous applications of hydrogen peroxide (H2O2), under greenhouse conditions. The experimental design used was randomized blocks in 5 x 5 factorial scheme, corresponding to the combination of five levels of irrigation water electrical conductivity – ECw (0.7, 1.4, 2.1, 2.8 and 3.5 dS m-1) and five concentrations of hydrogen peroxide (0, 25, 50, 75 and 100 µM). The results showed that Hydrogen peroxide concentrations were applied by soaking the seed for 24 h and by spraying on all leaves of soursop seedlings. Irrigation water above electrical conductivity of 0.7 dS m-1 negatively affected growth and quality of soursop seedlings cv. Morada Nova. The dry phytomass of root was the most sensitive variable to saline stress. Hydrogen peroxide concentrations of 31 and 100 µM led to highest relative growth rate in leaf area and dry phytomass of leaves and stem, respectively. The quality of soursop seedlings cv. Morada Nova was not compromised by using water with electrical conductivity of 3.5 dS m-1 in irrigation.