Dry Matter Of Aerial Part Research Articles

Sodium Chloride Tolerance during Germination and Seedling Stages of Tomato (Solanum lycopersicum L.) Lines Native to Mexico

Tomato is considered moderately sensitive to salinity, which detracts from the quality and yield of its fruit; therefore, wild populations have been used as a genetic resource. The aim of this research was to identify lines derived from wild tomato populations with tolerance to salinity during the germination and seedling stages. During germination, 52 wild lines and 2 commercial hybrids (Imperial®, Reserva®) were subjected to treatment with 150 mM and 0 mM NaCl and evaluated. The test was carried out for 20 days in a germination chamber with constant darkness, a temperature of 25 ± 2 °C and relative humidity conditions of 80 ± 4%. At the seedling stage, 22 wild tomato lines with the best performance in the germination test and 2 commercial hybrids (Imperial®, Topanga®) were evaluated for 12 days in a floating raft system. Concentrations of 175 mM and 0 mM of NaCl were used. During germination, the saline condition decreased the germination percentage (65.2%), speed of germination (88.2%), steam length (72.5%), root length (46.56%), number of normal plants (59.5%), stem dry matter (68.78%), root dry matter (61.99%), and total dry matter (67.1%). At the seedling stage, this condition decreased (p < 0.05) the aerial part dry matter (46.37%), leaf area (59.35%), root length (42.43%), final plant height (40.24%), and growth rate (71.42%). Seventeen tolerant genotypes were identified in one of the two developmental stages, while one genotype showed tolerance in both stages. These results indicate that there are different response mechanisms in each developmental stage. Native tomatoes play an important role in the identification of tolerant genotypes since they can be used as genetic resources for obtaining commercial genotypes with salt tolerance.

Physiological quality of soybean seeds produced under different spatial arrangements of plants

The present study aimed to evaluate the physiological effect of seeds on soybean genotypes in the southern region of Rio Grande do Sul. The test was developed in the field, in two agricultural crops, on a farm located in the District of Monte Bonito - Pelotas (RS, Brazil), in eutrophic haplic planosol soil, with geographic coordinates 31° 40' 27"S and 52°23' 28 "W. The experiment consisted of twelve treatments involving two factors: factor A - 3 soybean genotypes (NA 5909 RR (super early, growth indeterminate and maturation group A), NS 6006 IPRO (high grain weight, growth indeterminate and maturation group B 5.9), and NS 5959 IPRO (precocity, indeterminate growth and maturation group C) and factor B - 4 line spacing (0.17; 0.30; 0.45 and 0.60 meters). The experimental design used was randomized blocks in a factorial scheme (3x4) with four blocks. The plant population used was 330.000 plants ha-1. The evaluations of the physiological performance of seeds were germination, first germination count, length and dry matter of aerial part, root, and a total of seedlings, accelerated aging, and emergence in the field. Soybean plants better distributed in the cultivation area, in spacings of 0.17 and 0.30 meters, present greater plant height, stem diameter, and productive performance.the only genotype that presented a reduction in germination as the row spacing increased was 'NS 6006 IPRO', resulting in seeds with lower germination in the spacings of 0.45 and 0.60 m compared to the other genotypes under study. The reduction in the spacings, 0.17 and 0.30 meters, produced seeds with better physiological quality, evidenced in years with rain preceding the harvest.

Influence of soil attributes and sorption coefficient in defining diuron doses

The selectivity of diuron for most crops, is due to the positioning of its molecule in the soil profile. Therefore, it is necessary to know the interactions of diuron's molecule with soil matrix to define recommended doses from an agronomic and environmental standpoint. This research aimed to estimate the influence of soil attributes and sorption coefficient (Kf) on the definition of diuron doses. Experiments were conducted to quantify the Kf of diuron in different soils and determine the doses in each soil that caused 80% intoxication (C80 intoxication) and 80% decreased accumulation of aerial parts plants (C80 DMAP) of Eleusine indica. After that, a correlation analysis was performed between the soil physical-chemical attributes, diuron Kf, and C80 of E. indica intoxication. Diuron Kf ranged from 1.8, in the ultisol with 0% of manure content, to 8.8, in the oxisol with 40% of manure content. Eleusine indica C80 ranged from 66.3, in the oxisol with 0% of manure content, to 568.3 g a.i. ha−1, in the ultisol with 40% of manure content, while C80 of aerial part dry matter reduction ranged from 57.5 to 521.6 g a.i. ha−1 in the same soils. C80 intoxication positively correlated with organic matter content and Kf. It was concluded that organic matter content was determinant in diuron sorption and intoxication for E. indica. Changes are necessary in the dosing recommendation criteria in the label of diuron, with its recommendation being primarily based on the organic matter content.

The key role of indole-3-acetic acid biosynthesis by Bacillus thuringiensis RZ2MS9 in promoting maize growth revealed by the ipdC gene knockout mediated by the CRISPR-Cas9 system

The bacterial biosynthesis of indole-3-acetic acid (IAA) is often related to the beneficial effects of plant growth-promoting rhizobacteria (PGPR) on plant development. In PGPR belonging to the Bacillus genus, the synthesis of IAA may occur through different metabolic pathways that are still poorly understood. B. thuringiensis (Bt) is well known for its insecticidal properties; however, its beneficial features are not limited to pest control. Our group has been studed the beneficial effects of Bt strain RZ2MS9 as growth promoter in a range of plant crops, including soybean, tomato, and maize. We recently demonstrated that bacterial IAA biosynthesis plays an important role in the ability of RZ2MS9 to benefit plant development. However, the molecular involved mechanisms in the IAA biosynthesis by this bacterium in the beneficial interaction with plants remain unclear. Here, we investigated the genetic basis of IAA biosynthesis by RZ2MS9. We knocked out the ipdC gene, involved in IAA biosynthesis via the tryptophan-dependent IPyA pathway, using the CRISPR-Cas9 system. Our results showed that, by disrupting the IPyA pathway, the amount of IAA synthesized by the mutant RZ2MS9 (ΔipdC) in the presence of tryptophan drops 57%. The gene knockout did not affect the bacterial growth, but it did affect its ability to colonize maize. Moreover, deactivating the ipdC gene in RZ2MS9 significantly reduces its ability to promote maize growth. ΔipdC performed worse than RZ2MS9 in almost all evaluated plant parameters, including total root length, projected root area, lateral roots, aerial part dry matter, and germination speed index. Therefore, we demonstrated that tryptophan-dependent IAA biosynthesis via the IPyA pathway by RZ2MS9 is strongly influenced by the ipdC gene. Furthermore, IAA biosynthesis by RZ2MS9 is a major mechanism used by this PGPR to promote maize growth.

USE OF RHIZOBIUMBACTERIA TO INCREASE THE PRODUCTION OF FIVE TROPICAL LEGUMES WITH FORAGE POTENTIAL

The objective of the work was to evaluate the effect of the application of Rhizobium bacteria in the biomass production of forage legumes. Rhizobiumstrains were isolated and selected from the rhizosphere of five forage species. Characterization and subsequent cultivation were carried out to inoculate plants in a greenhouse. Subsequently, the biofertilizer was prepared to apply it to five forage legumes: C. ternatea, L. leucocephala, C. macrocarpum, M. pruriens and C. cajan. Plants were germinated in petri dishes and on substrate, after 10 days of germination, they were transplanted into Leonards Jugs and watered with distilled water. The plants were placed in a completely randomized design with three replicates. The evaluations were carried out every week measuring plant heightand at the end of the experiment root weigh, dry matter of aerial part and radicular volume. The best values obtained were in M. pruriens which showed from 49 to 50 cm of plant height. For cross inoculation in weight variable was observed that the strains from C. ternatea and L. leucocephala showed the best results with 0.22 and 0.25 g/plant respectively. Although the best data of dry matter of aerial part was observed in L. leucocephalawith 0.40 g, better response of Radicular volume and plant height was observed in strains that came from C. ternatea with 2 mL and 7 cm respectively. In this study it can be conclude that the use of biofertilizers can be an alternative for low-cost forage production, as long as it contains Rhizobium strains capable of associating with legumes and fixing atmospheric nitrogen.

Application of different nitrogen doses in fertirrigated cacao seedlings

The Medicilândia municipality is the main dried cocoa beans producer in Pará state, however, researches are being carried out in relation to the seedlings production. The study objective was to study the cacao seminal seedlings growth under a drip irrigation system, receiving different nitrogen doses with fixed doses of phosphorus (4,5 g) and potassium (3 g) through fertirrigation. The experiment was realized under greenhouse conditions with four treatments and five repetitions in a design of randomized blocks, being each composed by seven plants. Thus, T1 = check, without fertilization; T2 = 2 g of N + P and K; T3 = 7 g of N + P and K; T4 = 12 g of N + P and K. The treatments were scientific from the 31st to the 156th day after sowing, where the values of height, collar diameter and leaves number were obtained fortnightly. On the 156th day, the plants were harvested and obtained the root length, fresh matter and aerial part dry matter and root and the nutritional contents from the leaf and root plant tissue. The plants obtain results with the highest values of height, collar diameter and leaves number in the T2 treatment.

Silicon alters early development of bean seedlings from seeds infected by Anthracnose

The present study aimed to evaluate the effect of seed coating with Si in response to infection in a cultivar susceptible and resistant to Colletotrichum lindemuthianum, on the physiological and health potential of seeds and seedlings, during the initial development of bean culture. The experiment was carried out in a completely randomizeddesign, in a 2 × 2 × 2 factorial scheme, with four replications, where the factors were: cultivar (BRS Esplendor and IPR Tuiuiú), silicate application (with and without Agrosilício® coating) and inoculation (seeds inoculated or not with C. lindemuthianum). In the evaluation of the initial development of the culture, the following variables were measured: germination, first count of the germination test, emergence, emergence speed index (IVE), total seedling length, shoot and root length, total dry mass, aerial part dry matter, root dry matter and aerial part dry matter at 15 days after sowing (DAS). The incidence of C. lindemuthianumin beans was determined by the paper roll method. Covering the seeds with Si reduces the incidence and severity of C. lindemuthianumand provides greater growth of bean seedlings. The effect of responses potentiated by Si is more expressive in the cultivar of greater susceptibility.

Nonlinear models. An approach to model irrigated and non-irrigated common bean (Phaseolus vulgaris L.) growth

Common beans reduce their development and productivity when facing soil water deficit. Comprehension about growth response under this condition can be a tool for cultivar selection and escape from scarcity periods. Therefore, the objective was to characterize bean growth in different water conditions using logistic and chanter models. Two experiments (crop season= EI and fallow season = EII) were carried out in Santa Maria, RS, Brazil in a bifactorial scheme (cultivars: Triunfo, Garapiá, FC104; water condition: irrigated, not irrigated) in a completely randomized design. Fortnightly evaluations of height, number of nodes, stem diameter, root length, aerial part, roots, and nodules dry matter were carried out. The data were adjusted according to the accumulated thermal sum by the logistic and chanter models. From the results, it is noted that there was a dissimilar performance between water conditions, cultivars, and experiments. The best adjustment occurred for stem diameter, node number, and aerial part dry matter. Between models, the logistic is the most suitable to describe common bean growth.

Determination of the optimum plot size for tomato seedlings

The objectives of this work were to determine the optimum plot size for tomato seedlings by Hatheway’s method, using the Mestiço and Ozone cultivars, and verify the possibility to obtain the optimum plot size only by non-destructive characteristics. Non-destructives (aerial part height, stem diameter, number of leaves and leaf area) and destructives (aerial part dry matter, root dry matter, total dry matter and Dickson quality index) characteristics were evaluated. For each characteristic evaluated, experimental plans were simulated in a randomized block design with the combination of I treatments (I = 3, 4, 5, ..., 10, 15, 20 and 25) and R repetitions (R= 3, 4, 5, 6 and 7). The optimum plot size ranged according to the characteristic evaluated. Considering the number of treatments, repetitions and the same experimental accuracy, the stem diameter showed the highest size plot. Thus, the stem diameter can be used as a basis characteristic for the non-destructives characteristics, without the need to destroy the seedling.

Desempenho fotossintético, peroxidação lipídica e aspectos morfológicos de papuã exposto a diferentes condições hídricas do solo

This paper aimed to elucidate the behavior of Urochloa plantaginea biotype with differential physiological characteristics, which allows a better growth and development in a flooded environment. A completely randomized experimental design was used 2x3, being the factors: populations of Urochloa plantaginea (lowlands and highlands) and soil water conditions (50% and 100% of soil water retention capacity (CRA); water depth 5 cm). Responses related to photosynthetic parameters and lipid peroxidation were verified 24h and 192h after the onset of water conditions. Morphology-relatedvariables were measured at the end of the plant cycle. The lowland biotype compared to the highland biotype showed superior morphophysiological characteristics under soil flooding. It can be emphasized, higher water use efficiency (about 30%), higher plant height, lower aerial part lipid peroxidation and higher aerial part dry matter increment. In addition, the lowland biotype was shown not to vary photosynthetic parameters A, Gs, Ci, E, USA and A / Ci when exposed to the water depth 5 cm, compared with the 100%CRA condition. Both populations survived and ended their cycle producing seeds. Thus, apossible adaptive process of the population to the flooded environment is evidenced.

Seed potato minitubers production in a reused substrate

Minituber production is an important step to obtain high-quality seed potatoes. This production is carried out in a greenhouse using a large volume of commercial substrate acquired in specialized trade. An alternative to reduce the volume of substrate purchased for each production of minitubers would be to reuse it, which would be a way to optimize its use. The objective of this study was to evaluate the efficiency of reused substrates in the minituber production. The experiment was conducted in Tapira-MG with the Atlantic potato cultivar. The experimental design was a randomized block with six treatments and four replications, where each plot was represented by a box (0.15 x 0.4 x 0.5m: height, width, and length, respectively) containing substrates. Treatments consisted of formulation 04-14-08 rates (0, 25, 50, 75, and 100 g box-1) added to reused substrate and a control consisting of a new virgin substrate. At 45 days after transplanting, the following characteristics were evaluated: stem size (cm), and quantities of fresh and dry matter of aerial part of plants. Harvesting was performed manually, counting, and calculating the yield of tubers according to class. The reuse substrate with enriched nutrient regardless of the rate, when compared to the use of a new virgin substrate, did not interfere in potato plant development and in the total productivity of minitubers of classes I, II, III, and IV. This can be a feasible alternative for optimizing the use of the virgin substrate. The rate of 25 g box-1 of 4-14-8 is sufficient to provide the needs of potato in nutrients, ensuring high productivity.

Superação de dormência de sementes e desenvolvimento de mudas de jatobazeiro em substratos alternativos

The propagation of the jatoba (Hymenaea courbarilL.) by seeds is highly promising in the recovery of degraded areas. Thus, the present research aimed to compare methods forjatoba plant seeds dormancy overcomingand to evaluate the development of seedlings of this species in alternative substrates. In the first experiment, in screened nursery, a completely randomized design was used, with four replications and seven seed treatments: scarification with sandpaper(SS), SS and immersion in water for 24 h, SS and immersion in water for 48 h, intact seed, seed immersed in water for 48 h and seed immersed in water for 96 h. The seedlings that emergency were counted every other days, from 13 to 51days after sowing, quantifying the emergence percentage, the emergence speed index and the emergence average time.The second experiment, in greenhouse,was composed ofthree replicates, in randomized blocks, being seven substrates were used:commercial substrate (CS); 40% SC + 60% forest humus (FH); 40% SC + 60% charcoal rice husk (CRH); 40% SC + 60% bovine manure (BM); 40% CRH + 60% BM; 40% CRH + 60% FH; e 40% FH + 60% BM. At 50, 70 and 120 days after sowing were evaluated the parameters: seedlingheight, leafsnumber, stem diameter, fresh matterand dry matter of aerial partand roots, and leaf area.At 120 DAS, the chlorophyll index was also evaluated. The scarification with sandpaper and immersion of seeds in water for 24 hours presented a greater emergence (96.4% and IVE = 0.697).The mixture containing 40% FHand 60% BMresulted seedlings with a larger leaf area, chlorophyll index and roots and aerial part dry matter, at 120 days after sowing.

Initial Growth of Physalis peruviana L. Seedlings on Different Substrates

The substrate is one of the most important factors in the formation of the seedling and must present conditions suitable for germination and development of the seedling root system. The objective of this work was to evaluate the effect of different substrates on the initial growth of Physalis peruviana L. seedlings. The experiment was conducted at the Experimental Farm, of the Federal University of Espírito Santo– São Mateus (Brazil). The experimental design used was completely randomized, with three treatments (Soil, Provaso® and Bioplant®), seven replications and seven plants per plot, using seeds with 427 days of storage. At 56 days after sowing, the 10 most vigorous seedlings were selected for evaluation. The following characteristics were evaluated: percentage of emergence, emergence speed index (ESI), mean time of emergence (MET), number of leaves (NL), stem diameter (SD), aerial part length (APL), aerial part fresh matter (APFM), aerial part dry matter (APDM), root fresh matter (RFM), root dry matter (RDM) and Dickson quality index (DQI). The Provaso® substrate showed the best performance in all studied variables, being recommended for the production of Physalis seedlings.

Productive traits of rye cultivars grown under different sowing seasons

ABSTRACT This study aimed to adjust the Gompertz and Logistic nonlinear models for the fresh and dry matter of aerial part and indicate the model that best describes the growth of two rye cultivars in five sowing seasons, as well as to characterize the growth of the cultivars regarding the fresh and dry matter of aerial part. Ten uniformity trials were conducted with the rye crop in 2016. A weekly sampling and evaluation of 10 plants per trial was performed from the time the plants presented one expanded leaf. For each plant, the fresh and dry matter of aerial part were weighed. The Gompertz and Logistic models were adjusted to the accumulated thermal time based on the measures of each trait in each assessment. Also the parameters a, b, and c for each model were estimated and calculated the interval of confidence for each parameter, as well as the inflection points, maximum acceleration, maximum deceleration and asymptotic deceleration. The quality of the model adjustments was verified using the coefficient of determination, Akaike information criterion, and residual standard deviation. The intrinsic nonlinearity and nonlinearity of the parameter effect was quantified. Both models satisfactorily describe the behavior of the fresh and dry matter of aerial part. The Logistic model best describes the growth of rye cultivars. The growth of the cultivars BRS Progresso and Temprano is distinct between sowing seasons. Cultivar BRS Progresso requires a lower thermal time until reaching 50% of its growth when compared to the Temprano cultivar.

Propagation of Piper carniconnectivum through leaf cuttings

The regeneration of roots and shoots through leaf cuttings is a feasible technique for plant clonal propagation, using a quite available organ, which can be collected without great damage to the plant. A protocol of propagation through leaf cuttings was defined to Piper carniconnectivum, a plant whose compounds have great potential use in medicine and agriculture. Leaves were cut in halves (apical and petiolar) by transverse cutting in the middle of the leaf blade. The petiolar parts were immersed into a solution of indole 3-butyric acid (IBA) at 1000 ppm for 30 seconds, or not submitted to the hormone. Then the cuttings were planted in soil, using two positions of the petiolar halves: petiole down and petiole up. A factorial design was used – 2 times of immersion in IBA x 2 leaf half position x 3 blocs x 6 replications. After 145 days the number of shoots, shoot length, leaf area, dry matter of aerial part, root volume and root dry matter were evaluated. The highest number of shoots was observed in the petiole down position without IBA. In relation to the other aerial characteristics – shoot length, leaf area and dry matter of the aerial part, the highest values were observed both in the petiole down position without IBA and in the petiole up position with immersion in IBA. The characteristics related to the root – root volume and root dry matter were both highest in the petiole up position with immersion in IBA. Leaf cuttings can be a practical method to propagate P. carniconnectivum vegetatively. Both petiole up cutting with immersion in IBA and petiole down cutting without immersion in hormone can be used as propagules.

Effect of Trichoderma spp. fungus for production of seedlings in Enterolobium Schomburgkii (Benth.) Benth

Enterolobium schomburgkii (monkey ear) is important Amazonic forest specie, being used for wood and medicinal purposes and environmental recuperation issues. Biological treatment such as Trichoderma fungus is alternative method that may improve performance of seeds germination and provide healthy seedlings. We aimed to assess effect of Trichoderma fungus on development of E. schomburgkii seedlings. Five isolates of Trichoderma spp., in the concentration of 1.0 x 107 conidia.mL-1, were assessed and applied through four methods: seeds; pre-planting substrate; post-planting substrate; and seed + pre-planting + post-planting substrate. The seedlings were produced in polypropylene bags and kept in nursery for 10 months. The experimental design was completely randomized, in a 5x4+1 factorial scheme, with 10 repetitions. We monthly assessed the plant height, collar diameter and number of leaves and leaflets. After 10 months, we assessed root length, dry matter of aerial part and dry matter of roots system. The results showed that variables were significantly influenced by Trichoderma isolates and its application modes, either individually or under interaction, except on the root length. Eight treatments boosted the plants height and five of them increased the collar diameter, compared with the control. The height of the seedlings was the variable that mostly influenced by the treatments. Application of Trichoderma in pre-planting substrate influenced the highest number of variables analyzed. Therefore, the isolates application used in this work is feasible for production of Enterolobium schomburgkii seedlings. Based on results of this experiment we do not recommended treatment of Enterolobium schomburgkii seeds with Trichoderma isolates, except using T. asperellum T09

Plant growth and physiological quality of quinoa (Chenopodium quinoa Willd) seeds grown in Southern Rio Grande do Sul, Brazil

Quinoa (Chenopodium quinoa Willd) an annual grain crop belonging to the Amaranthacea family is the only vegetable food that contains all essential amino acids, micronutrients and vitamins. The study aimed to evaluate the performance, growth and seed physiological quality of two genotypes of quinoa in Southern Rio Grande do Sul region. The cultivar BRS Piabiru and one breeding line were grown at green house. The design was completely randomized with four replications and five harvest times during the vegetative stage of the crop. The variables were shoot length, number of leaves, leaf area index, dry matter of aerial parts, dry matter of root and total dry matter of plant. It was concluded that the line and BRS Piabiru have slow initial growth in the first 30 days and strong growth up to 120 days. The breeding line and commercial cultivar showed the same potential for seed production in the temperate climate of this region.

Arabica coffee progenies with multiple resistant to root-knot nematodes

The root-knot nematode Meloidogyne paranaensis is considered the major threat in Coffea arabica plantations. Due to the aggressiveness of this nematode, cultivation is virtually impossible without a resistant cultivar. The main goal of this research was to identify resistant progenies derived from crossings of Catuai and Timor hybrid cultivars in a greenhouse experiment. Additionally, genetic parameters for resistance were estimated to trace selection strategies. Coffee plants were inoculated with 9000 M. paranaensis eggs and second-stage juveniles (J2). Eighty-six plants previously selected in a Meloydogine exigua infested field gave rise to 86 progenies that were evaluated based on the dry matter of aerial parts (DMAP), fresh matter of extracted root (FMER), height (H), and diameter (DIA). The responses of the progenies to nematodes were assessed using the gall index and thickness (GIT), number of eggs J2/g root (NEJGR), and reproduction factor (RF).The cultivars Mundo Novo IAC 379-19, Catuai Vermelho IAC 99, Paraiso MG H 419-1, and IPR 100 were used as susceptible and resistant controls. The GIT is genetically correlated with NEJGR and RF, and could be used in plant selection programs. Five progenies were resistant to M. paranaensis, with two of them not segregated to susceptibility. These progenies are considered multiple resistant to root-knot nematodes because they are also resistant to M. exigua.

Competitive Ability of Canola Hybrids Resistant and Susceptible to Herbicides

ABSTRACT: This work aimed to compare the competitive ability of canola hybrids susceptible (conventional) or resistant to triazine or imidazolinone group herbicides, with turnip. The experiments were conducted in greenhouse, in a completely randomized design, with four replicates. The hybrids Hyola 571CL (resistant to imidazolinone), Hyola 555TT (resistant to triazine), and Hyola 61 (conventional) were used. The treatments consisted of ratios (100:0; 75:25; 50:50; 25:75; 0:100%) of canola and turnip plants. The evaluation was performed 44 days after emergence, determining the leaf área (AF), dry matter of aerial part (MSPA), and stature (EST) of the plants. The competitiveness analysis was performed through diagrams and interpretation of the competitiveness indexes. For the canola hybrids, the competition occurred by the same mean resources. There was damage to the crop growth in competition with the turnip. The turnip was not benefited only when in competition with Hyola 571CL hybrid, for the EST variable, and with the conventional canola, for the variable AF. There was significance for the competitiveness indexes, demonstrating that turnip is more competitive then the crop. Greater AF, MSPA, and EST occurred for canola plants in the smallest proportions of turnip and, for turnip plants, in the largest proportions of canola. The ability to compete with turnip is similar among hybrids, with injury to the crop and benefit to the weed, when competing. Interspecific competition is more damaging to canola hybrids; and intraspecific competition is more damaging to turnip.

English

The objective of this study was to determine the stage of development with greater sensitivity to water excess and the period of time required to compromise the emergence and grain yield components of canola. The experiments were performed in a greenhouse at the Federal University of Santa Maria and at the Farroupilha Federal Institute, Campus of Sao Vicente do Sul, RS during the 2015 agricultural year. The completely randomized experimental design was utilized to investigate phenological stages and periods of continuous water excess in the soil. Also, factors like percentage of emergence, emergence speed index, grain yield, number of siliques per plant, one hundred grains weight, dry matter of aerial part, silique length, number of grains per silique, and weight of 20 siliques were determined. The stages of rosette leaf formation and beginning of anthesis are the most sensitive to water excess in the soil. Water excess for 24 h is enough to reduce the emergence speed index. However, the percentage of emergence is not compromised by water excess up to 192 continuous hours. 24 h of water excess reduces the number of siliques per plant, dry matter of aerial part and grain yield of canola. Key words: Brassica napus, grain yield, lowland cultivation, waterlogging.