Response Of Lettuce Research Articles

Morphological and Physiological Stress Responses of Lettuce to Different Intensities of Continuous Light.

In this study, specific dynamic changes in growth, oxidative stress, ascorbate metabolism, and chlorophyll fluorescence were monitored during 12 days in lettuce plants exposed to continuous light (CL) of different intensities: low light (LL, 100 μmol·m−2·s−1), medium light (ML, 200 μmol·m−2·s−1), and high light (HL, 300 μmol·m−2·s−1). Lettuce plants grown under CL of higher light intensity gained greater biomass, dry weight ratio, root/shoot ratio, and specific leaf FW, but not leaf area. Both the reactive oxygen species (ROS) production and the lipid peroxidation degree, measured in terms of the malondialdehyde (MDA) levels, were progressively enhanced by increasing the light intensity of CL. Overall, the pool sizes of ascorbate (AsA) and glutathione, as well as the activities of enzymes involved in AsA metabolism, had positive correlations with light intensity under CL. Ascorbate peroxidase and dehydroascorbate reductase presented the maximal and minimal responses to light intensity, respectively, among all the studied enzymes. After 6 days under CL, ML and HL intensity caused reversible photoinhibition, represented by lower values of maximum quantum efficiency (F v /F m), effective quantum yield (ΦPSII), and photochemical quenching (qP) and a higher value of non-photochemical quenching (qN). However, this photoinhibition recovered on day 12 with increasing of F v /F m, ΦPSII, and qP. Taken together, under ML and HL conditions, greater AsA level could help maintain photosynthetic efficiency by elevating excess excitation energy dissipation, though ROS accumulation and lipid peroxidation could not be prevented in the long-term. Likewise, there was no dark period under LL condition, but no photooxidative stress was observed in lettuce. Thus, it is concluded that photooxidative stress induced by CL can be attributed to excessive daily light integral instead of circadian asynchrony.

Respon Tanaman Selada Merah (Lactuca Sativa L.) Terhadap Larutan Hara (AB Mix ) Pada Instalasi Horizontal Sistem Hidroponik

This study aims to determine the response given by the red lettuce plant to the provision of nutrients in the form of nutrient solution (AB Mix) on the horizontal installation of the hydroponic system. The study was conducted on December 20, 2017 until February 16, 2018 at the PKK Gardens Education Center in Bengkulu province. Seeding process of Red Lettuce Seedlings is carried out for 14 days then transferred to a net pot at the installation in the Greenhouse. Fertilizers with the Fiora A and B Brands are dissolved to be mixed in a nutrient bath with a capacity of 3000 L with a nutrient density of 500 ppm in the Greenhouse to be distributed to the horizontal installation of the hydroponic system inside the Greenhouse. Then growth observations were carried out on 10 plant samples with parameters of leaf length, leaf width, number of leaves, stem height, andstem diameter for 30 days. The results obtained by sample 1-10 have an average growth and development that is not much different. The maximum leaf length and leaf width parameters are in samples 2 and 3. While the highest number of leaf strands in sample 3 is 22 strands with an average of 18 strands and sample 4 has the highest stem height parameter of 3.5 cm with an average height 2.7 cm. The largest stem diameter in sample 4 is 4.1 cm with an average of 3.38 cm. The response of red lettuce after the last week showed symptoms of leaves that are less red with relatively more withered body.

Morphological and physiological properties of indoor cultivated lettuce in response to additional far-red light

Understanding the wavelength-dependence of plant responses is of particular importance to optimize production and quality. Far-red (FR) light is known to regulate phytochrome-mediated morphological and physiological plant responses, while limited attention has been paid to the benefits of including FR light to indoor plant cultivation. Lettuce (Lactuca sativa L. cv. ‘Tiberius’) plants were grown under a fully controlled environment, in which three different light treatments were arranged. The photosynthetic photon flux density (PPFD) was 200 μmol m−2 s−1 provided by a mixture of red and blue light (red/blue light ratio was 7:1) with peak intensities at 450 nm and 660 nm, respectively. In two of the treatments, 50 μmol m−2 s−1 FR light with peak intensity at 740 nm was supplemented during the day (FR-Day, 16 h) or end of the day (FR-EOD, 1 h). Plant total biomass was increased by 39% and 25% in the FR-Day and FR-EOD treatment, respectively, compared with the control. Adding FR light resulted in 27–49 % larger plant leaf area with an open plant canopy, which facilitated a better light interception and led to higher plant radiation use efficiency (RUE). Although temporarily adding FR light increased net leaf photosynthetic rates by 7–10 %, FR light treatments resulted in a significantly lower chlorophyll and total nitrogen content, as well as lower leaf absorbance, which led to lower maximum leaf photosynthetic rate. Such downregulation had limited effect on plant growth as the net leaf photosynthetic rates in their corresponding growth environments were similar between treatments. The extent of FR light induced leaf physiological modifications was lower in the FR-EOD treatment, in comparison with the FR-Day treatment. Our estimation showed that ˜36% and ˜94% of the enhanced dry mass production in the FR-Day and FR-EOD treatments, respectively, could be attributed to the FR light regulated RUE improvements, the other part enhanced dry mass production might be the consequence of additional light. We conclude that the acclimation process of plant morphology triggered by additional FR light plays a pivotal role for improving the production of indoor cultivated lettuce, and the enhanced production by additional FR light cannot be achieved by adding similar amount of red and blue light.

Yield and quality of lettuce in response to the plant position in photovoltaic greenhouse

In recent years there has been an increasing spread of photovoltaic greenhouses, especially in southern European countries, due to the higher incentives recognized to solar photovoltaic (PV) panels integrated on the greenhouse roofs and/or to local laws which limit the photovoltaic systems on the ground. To maximize the income from the production of electricity, often solar panels cover 50% or more of the roof, but the shading caused by these elements on the growing surface seriously limits the productivity and affects crop development. In order to assess the effects of the spatial distribution of the solar radiation inside these structures on yield and quality of leaf vegetable crops, the response of lettuce, grown in two cycles (autumn and winter-spring), in an east-west oriented photovoltaic greenhouse with the 50% of the roof covered by PV modules was analysed. The influence of span orientation, plant position (under plastic or PV roof) and cultivar were analysed as experimental treatments in a split-split plot design with two replications. Total and marketable yield of the lettuce heads and some quality parameters (dry matter and nitrate content) were evaluated. A significant variability of the total and marketable yield due to the plant position and as consequence to the solar radiation distribution inside the structure during the growing cycle was observed. Furthermore, ranges and variability of the nitrate content of lettuce (expressed as NO(3) mg kg(‑1) of fresh weight) were affected by the plant position and harvest season. In order to maximize yield and quality of the crops, the arrangement of plant rows and transit areas, as well as the management of nutrition, should be optimized in relation to the shading caused by the PV roof during the growing cycle.

Evaluation of Biological Response of Lettuce (Lactuca sativa L.) and Weeds to Safranal Allelochemical of Saffron (Crocus sativus) by Using Static Exposure Method.

Safranal, the main volatile chemical of Saffron (Crocus sativus) was studied to estimate its allelopathic effects on the photosynthetic pigment chlorophyll, leaf electrolyte leakage, fresh weight, catalase (CAT), and peroxidase (POX) activity of the test plant Lettuce (Lactuca sativa). In this study, the effective concentration (EC50) of safranal on CAT was estimated to be 6.12 µg/cm3. CAT activity was inhibited in a dose-dependent manner by the increase in the safranal concentration while POX activity was increased. Moreover, Safranal caused significant physiological changes in chlorophyll content, leaf electrolyte leakage, and fresh weight of several weed species with Lolium multiflorum being the most sensitive. Furthermore, 5 µM Safranal showed significant inhibitory activity against dicotyledonous in comparison to the monocotyledons under greenhouse conditions. The inhibition of the CAT by safranal was similar to those of uncompetitive inhibitors, and therefore the decline in carbon fixation by plants might be the mechanism behind the inhibitory activity of safranal.

Sugar accumulation and growth of lettuce exposed to different lighting modes of red and blue LED light

The present study evaluated the growth response and sugar accumulation of lettuce exposed to different lighting modes of red and blue LED light based on the same daily light integral (7.49 μmol·m−2). Six lighting treatments were performed, that were monochromatic red light (R), monochromatic blue light (B), simultaneous red and blue light as the control (RB, R:B = 1:1), mixed modes of R, B and RB (R/RB/B, 4 h R to 4 h RB and then 4 h B), and alternating red and blue light with alternating intervals of 4 h and 1 h respectively recorded as R/B(4 h) and R/B(1 h). The Results showed that different irradiation modes led to obvious morphological changes in lettuce. Among all the treatments, the highest fresh and dry weight of lettuce shoot were both detected with R/B(1 h), significantly higher than the other treatments. Compared with plants treated with RB, the contents of fructose, glucose, crude fiber as well as the total sweetness index (TSI) of lettuce were significantly enhanced by R treatment; meanwhile, monochromatic R significantly promoted the activities of sucrose degrading enzymes such as acid invertase (AI) and neutral invertase (NI), while obviously reduced the activity of sucrose synthesizing enzyme (SPS). Additionally. The highest contents of sucrose and starch accompanied with the strongest activity of SPS were detected in plants treated with R/B(1 h). The alternating treatments R/B(4 h) and R/B(1 h) inhibited the activity of SS, while enhanced that of SPS compared with the other treatments, indicating that different light environment might influence sugar compositions via regulating the activities of sucrose metabolism enzymes. On the whole, R/B(1 h) was the optimal lighting strategy in terms of lettuce yield, taste and energy use efficiency in the present study.

The Response of Lettuce (Lactuca sativa L.) to The Types and Application Time of Agroprobiotic Fertilizer

The Response of Lettuce (Lactuca sativa L.) to The Types and Application Time of Agroprobiotic Fertilizer. Agroprobiotic fertilizer as an alternative of organic fertilizer is expected to reduce the use of chemical fertilizers. The aim of the study was to determine: (1) the best type of agroprobiotic fertilizer; (2) the best application time; (3) interaction between the two factors on the growth and yield of lettuce. The study was conducted from May until July 2018 at Faculty of Agriculture, Mulawarman University. The research was 5x2 factorial experiment arranged in Completely Randomized Design with six time replications. The first factor was the types of agroprobiotic fertilizer, namely: Maknyus; Cimelati; Mayas Putih; Keriting; and Hitam rice. The second factor was the application time of fertilizer, consisted of: in the morning (at 07.00-08.00) and in the afternoon (at 17.00-18.00). The variables observed consisted of: the increment of plant height and number of leaves increment at 14; 28; 42 days after treatment (DAT); and at harvest time, fresh weight, and leaves area. Data were analyzed by analysis of variance and continued with the Least Significant Difference (LSD) test at 5% level. The results showed that the types of agroprobiotic fertilizer and the interaction between the two factors had no significantly different on the growth and yield of lettuce. Agroprobiotic fertilizer from Mayas Putih rice showed the better growth and yield than others. The best time for application of fertilizer was in the morning, it showed significantly different on the increment of plant height at harvest time.

Growth, nutrient uptake and enzyme activity response of Lettuce (Lactuca sativa L.) to excess copper

Copper is an essential element for plants, but its higher concentration can make disruption in plant growth. The current study was conducted to determine the impact of excess copper (Control 0.2, 200 and 400 µM of copper sulfate) on growth, chlorophyll content, nutrient uptake and enzyme activity in lettuce. The results of this study highlighted that chlorophyll content, superoxide dismutase and ascorbate peroxidase activity were higher in the plants exposed to copper treatments. The peroxidase activity (POD) showed a different behavior depending upon the copper concentration; in this respect, 200 and 400 µM of copper sulfate increased POD activity by 59% and 32%, respectively in comparison to the untreated one. Copper application causes a decrease in leaf area (leaf expansion), root and shoot dry weight. Copper sulfate clearly decreased N, K, P, Si, Zn and Mg content in leaves and roots, whereas it increased B content in roots. Based on the outcomes of the current study, it can be concluded that lettuce showed tolerance to copper toxicity by alteration in mineral nutrition uptake, enzyme activity, chlorophyll content and leaf expansion.

Biomass and nutrient concentration of lettuce grown with organic fertilizers

The responses of lettuce (Lactuca sativa L. ‘Arroyo’) to organic nitrogen (N) fertilizers were investigated in a greenhouse. Fertilizers were blood meal (BLO), feather meal (FM), cottonseed meal, alfalfa meal, sewage sludge, compost, cow manure, a chemical fertilizer, and a treatment without fertilizer. Amounts of N from fertilizers were 100, 200, 400, or 800 mg per pot. Lettuce yield was higher for plants receiving fertilizers than with no fertilizer and increased with increased N applications, but high applications of BLO or FM suppressed yields. Nitrogen and nitrate increased in leaves as N supply increased with all fertilizers. Small changes in leaf nutrient contents other than N occurred among or with increased application of the various fertilizers. The soil carbon dioxide release and ammonia volatilization were high from fertilizers with high N concentrations. Organic fertilizers with high N increased lettuce growth at lower applications than those with low N content.

The response and tolerance mechanisms of lettuce (Lactuca sativa L.) exposed to nickel in a spiked soil system

Nickel contamination may lead to the destruction of food, ecological safety and its toxicity to plants remains to be studied in depth. In our present study, the translocation factors (TFsoil to root and TFroot to shoot) revealed a significant logarithmic decline with the increase of Ni exposure. In lettuce roots, NiHAC played an important protective role against high Ni stress and the ratio of Ni with high activity (NiE and NiW) in root decreased with the addition of Ni. The activities of antioxidant enzymes (CAT, POD and SOD) in the lettuce roots were increased and might be the way for lettuce to adapt Ni stress. CAT and POD can be great indicators of Ni pollution exhibiting better dose-effect relationships with Ni. Under high Ni stress, lettuce roots contained higher levels of MDA suffering greater pressure than shoots. Expression levels of gene GST 23-like indicated a remarkable (P < 0.05) down-regulation and then this trend would be alleviated after high Ni exposure, and it was positively correlated with GST concentrations (R2 = 0.704). We believe that our research would open up the new avenues for effective understanding ecological risks of Ni.

Morpho-physiological and homeostatic adaptive responses triggered by omeprazole enhance lettuce tolerance to salt stress

Natural or synthetic small molecules (<500 Da), bioactive at very low concentrations, can potentially increase plant tolerance and resilience to abiotic stresses and improve the resources use efficiency (RUE) of a wide range of crops. Hence, they represent a promising tool in coping with the increasing global food demand imposed by climate change. In this study, the responses of butterhead lettuce (cv. Trocadero) treated with omeprazole (OMP), a benzimidazole inhibitor of animal proton pumps, were studied. OMP was applied as substrate drench at five rates (0, 10, 50, 100 or 200 μM) on lettuce plants grown under nonsaline or saline conditions of 1 or 30 mM NaCl. Increasing NaCl concentration decreased lettuce fresh and dry biomass by 37% and 25% in the 0 μM OMP treatment, respectively; whereas these reductions were mitigated by the 10 μM (12% and 19%, respectively) and 50 μM (15% and 14%, respectively) OMP application. Though OMP was not directly involved in ion homeostasis and K+/Na+ ratio regulation, treatment with 10 μM OMP under saline conditions decreased Na+ in leaves and Cl− in leaves and roots while increasing NO3− concentration in both organs. The synthesis of nitrogenous osmolytes may be implicated in increasing salt tolerance and the sustenance of transpiration and photosynthesis. Under nonsaline conditions, OMP increased root biomass, improving nutrient and water uptake, and therefore RUE.

Divergence in response of lettuce (var. ramosa Hort.) to copper oxide nanoparticles/microparticles as potential agricultural fertilizer

ABSTRACTCuO particles can be used as an agrochemical with slow and controlled release of micronutrients but, their size-specific effects have not been well elucidated. In this study, soil-grown lettuce was exposed to CuO nanoparticles (nCuO) and CuO microparticles (μCuO) at 0, 200, and 400 mg Cu/kg for 60 days. At harvest, nCuO released 82.2% and 117.7% more Cu ions, as well as 48.7% and 75.3% more DTPA-extractable Cu than μCuO at 200 and 400 mg/kg, respectively. CuO treatments induced higher copper accumulated in lettuce roots but did not change shoot’s Cu content or cause oxidative stress. nCuO treatments increased shoot’s biomass by 16.3–19.1%, while μCuO showed no improvement to the biomass. The beneficial effects on lettuce by nCuO may be attributed to its modification in plant photosynthesis system with increased transpiration rate and higher stomatal conductance. Results indicate that nCuO can be a promising agrochemical fertilizer to increase crop production.

Trichoderma asperellum T1 mediated antifungal activity and induced defense response against leaf spot fungi in lettuce (Lactuca sativa L.)

Leaf spot, caused by Corynespora cassiicola and Curvularia aeria, is a major disease of lettuce that results in the reduction of the quality and the quantity of lettuce production. Primary in vitro examination revealed that Trichoderma sp. T1 inhibited the mycelial growth of C. cassiicola and C. aeria by 83.79% and 85.71%, respectively, in dual culture assays. Gel diffusion showed cell-free culture filtrate of Trichoderma sp. T1 inhibited C. cassiicola and C. aeria by 50.38% and 53.97%, respectively. Based on the ITS gene sequence, an effective T1 isolate was identified as Trichoderma asperellum. Treatments of lettuce plants with spore suspension of T. asperellum T1 induced defense-related enzymes such as peroxidase and polyphenol oxidase, and the cell wall degrading enzymes β-1,3-glucanase and chitinase in the plants. The activities of β-1,3-glucanase, chitinase, peroxidase and polyphenol oxidase were higher at 24 and 48 h after treatment with spore suspension of T. asperellum T1 than in the control group. Crude extract from inoculated lettuce caused morphology changes in fungal mycelia. In addition, reduction of disease severity was observed in lettuce pretreated with T. asperellum T1. The obtained results suggest that T. asperellum T1 efficiently controlled leaf spot and induced defense responses in lettuce.

Response of Lettuce (Lactuca Sativa L.) under Different Nutrient Solutions Grown Hydroponically with Aeration

Vegetables such as lettuce, sweet pepper, cucumber, and celery have been successfully grown using Simple Nutrient Addition Procedure (SNAP) hydroponics. Insufficient oxygen supply is one of the direct consequences of reduced growth performance of plants grown hydroponically. The possibility of having a SNAP hydroponics aerated would be very much promising in improving the growth, yield and profitability of producing lettuce. This study was conducted to evaluate the effect of aeration on the growth, yield and profitability of lettuce produced under two different nutrient solutions with and without aeration. Treatments (aeration intervals) were; no aeration, aeration daily, every 2, 3, 4, 5, and 6 days for 30 minutes until harvest. Aeration intervals significantly increase the polar diameter of lettuce with the widest head of 12.20cm (aerated every 2 days) as well as on leaf chlorophyll content where aeration daily have the highest. Peter’s hydrosol nutrient solution with and without aeration was more cost-effective in lettuce production compared to SNAP A+SNAP B.

Variety-specific responses of lettuce grown in a gravel-film technique closed hydroponic system to N supply on yield, morphology, phytochemicals, mineral content and safety

Utilization of nitrogen (N) element is a common practice used to reach profitable yields in horticultural crops and N supply can be used as a tool to manipulate the enhancement of phytochemicals and minerals in vegetable crops to address consumer-oriented quality production. Hence the study was aimed to investigate the effect of N application on leaf morphology, ascorbic acid content, phenolic acids, flavonoids, mineral content, and nitrate residues in three lettuce varieties (two green leafy lettuce, Multigreen 1 and Multigreen 3; one red leafy lettuce, Multired 4) grown in a closed hydroponic system (gravel-film) at harvest. Nitrogen was applied as ammonium nitrate (NH4NO3) at six different concentrations of 0, 60, 90, 120, 150 and 180 mg L−1. The results obtained during 2015 and 2016 seasons were similar and demonstrated variety dependent responses with respect to different N application rates. Multigreen 3 was more sensitive to N supply and showed higher amount of nitrate residue at harvest. Variety Multired 4 was less sensitive to N supply followed by Multigreen 1. Although N supply at 120 mg L−1 improved the yield and the number of leaves in Multigreen 3, overall 90 mg L−1 can be recommended for these lettuce varieties to improve the yield and the accumulation of ascorbic acid content, phenolic acids mainly caffeic, caftaric acids, quercetin (the important flavonoid in lettuce), and Fe and Mn contents. Furthermore, the concentration of 90 mg L−1 improved the antioxidant property (FRAP and ABTS+) and reduced the nitrate accumulation, ensuring safe food for consumers.

Transplant lettuce response to different blue:red photon flux ratios in indoor LED sole-source lighting production

Transplant lettuce response to different blue:red photon flux ratios in indoor LED sole-source lighting production

Response of Lettuce (Lactuca sativa L.) to Foliar Spray Using Nano-Urea Combined with Mycorrhiza

A factorial randomized complete block field experiment was carried out on lettuce (Lactuca sativa var. longifolia cv. Balady), grown on a heavy clay torrifluvent soil during two successive seasons (2016/2017 and 2017/2018) at the farm of the Faculty of Agriculture, Moshtohor, Benha University to study foliar application with nano-urea and biofertilization using Vesicular Arbusclar mycorrhiza (VAM). Factor 1 included 2 treatments: none (B0) and VAM (B1); Factor 2 included 5 treatments: no urea spray (spray with water) (N0), spray with ordinary urea at 5000 mg N L-1 (N1), spray with nano-urea at 2500 mg N L-1 (N2), 3750 mg N L-1 (N3) and 5000 mg N L-1(N4). Spray was in 3 times 30, 40 and 50 days after transplant at a rate of 1200 L ha-1each time. All growth parameters of plant height, number of leaves plant-1, fresh and plant dry weight increased by N or VAM singly or combined. Highest positive response occurred in plant height as well as weight and given by N3B1. All nano-urea treatments surpassed the ordinary one, particularly the middle nano rate. The highest nano rate seemed excessive since N3 did not continue to score further increase. Contents on N, P and K increased by nano-urea. NO3-N increased progressively with increased application of urea, and the increase progressed with increased rate of nano-urea. The nano application proved practical and more efficient since a concentration of as low as 2500 mg N L-1 proved superior to that of 5000 and mg N L-1 ordinary urea N.

Salicylic acid loaded chitosan microparticles applied to lettuce seedlings: Recycling shrimp fishing industry waste

Shrimp fishing industry wastes are still a main problem with high environmental impact worldwide. In this study, chitosan with ultra-high molecular weight and deacetylation degree ≥85% was obtained from shrimp fishing industry waste from Argentinean Patagonia. Chitosan based microparticles capable to entrap salicylic acid, a phytohormone known to play major role in the regulation of plant defense response against various pathogens, were prepared using TPP as crosslinker. Unloaded microparticles and microparticles loading several salicylic acid amount were fully characterized exhibiting a size between 1.57 μm and 2.45 μm. Furthermore, a good PDI, entrappment efficiencies from 59% to 98% and salicylic acid sustained release over 24 h were achieved.Chitosan based microparticles were non toxic in most of the doses applied in lettuce seedlings. Instead, microparticles can positively modulate plant growth and have the potential to improve plant defense responses. In particular salicylic acid loaded microparticles effect was very promising for its application as activators of salicylic acid dependent plant defense responses in lettuce as a model of horticultural plant species.

Physiological and Biochemical Responses of Lettuce to Thymol, as Allelochemical

Nowadays, allelopathic investigations have focused to identify action mechanisms of this compounds on target organisms in natural habitats. It may tend to introduce new natural herbicides and pesticides for replacing the synthetic ones. In the present study, the allelopathic effects of thymol on lettuce (Lactuca sativa L.) as a model plant were investigated in physiological and biochemical aspects. At the first stage, the effect of different concentrations of thymol on some growth parameters, including seed germination, radicle and plumule growth were evaluated to determine the optimum concentration for the continuation of our experiment. Then, the lettuce seedlings were cultured in pots containing peat and were irrigated with Hoagland nutrient solution supplemented with thymol at the concentration of 50 and 100 μg/mL. The effect of these treatments on physiological, biochemical aspects of the plant were studied following the plant growth. The results showed whereas, the shoot fresh and dry weights and photosynthetic rate in the treated group were decreased significantly compared to the control group at P ≤ 0.05, photochemical efficiency of photosystem II, total protein concentration, proline content and the activity of some antioxidant enzymes such as polyphenol oxidase, ascorbate peroxidase and catalase were increased in treated plants than control ones. However, there was no significantly change in chlorophyll content in treated group than control. It can be concluded that the thymol as an allelochemical caused some physiological and biochemical responses in the lettuce which are much similar to induced responses under abiotic stress. Indeed, it induces a kind of stress named as allelochemical stress.

Response of crisp lettuce (Lactuca sativa L.) to organic and inorganic sources of fertilization

The use of organic products to promote plant growth is becoming ever-more important as the paradigm of sustainable production of foodstuffs becomes increasingly common. Accordingly, the objective of the current study was to evaluate the response of lettuce to organic and inorganic sources of nutrients in soils representative of those found in Parana State, Brazil, across successive cultivations. Experimental methodology involved randomized blocks, with5 repetitions. Treatments used were: 1- control (Test);2-100% mineral fertilizer (MF); 3- 100% chicken litter (CL); 4- 100% liquid pig manure (LMP); 5- 50:50 mixture of CL and MF (CL+MF); 6- 50:50 mixture of LMP and MF (LMP+MF) and 7- 50% CA + 50% (CL+LMP). Experimental plot size was 0.7 m², and young Verônica cultivar individuals were planted with a 0.30 x 0.30 m spacing. There were two experimental plantings: in the first, the first using the treatments described above; the second, investigated the residual effect of fertilization of the first planting. For the first cropping, highest wet (326.5 and 315.4 g plant-1)and dry (14.2 and 19.74 g plant-1) above ground biomasses, were obtained with the LMP +MF and CL+MF treatments. No significant differences were encountered for the treatments in the second harvest. The effect of mineral fertilization in the production of Veronica cultivar lettuce, is greatest when it is combined with organic fertilization such as chicken litter (CL) or liquid pig manure (LMP).