ADDITION OF PROTOX INHIBITORS HERBICIDES TO GLYPHOSATE IN THE DESICCATION OF Urochloa brizantha BRS “Piatã”

In ornamental crop production, growth models as a function of environmental factors can be used as a valuable tool for predicting the timing of a phenological event for the average of a population, for the optimization of environmental conditions inside a growing system, and for making cultural decisions for increasing crop production. The feasibility of an expolinear growth equation was evaluated by predicting the crop growth of single-stemmed rose ‘Vital’ in a single stem system using recirculating nutrient solution. The objectives of this study were to determine a suitable environmental variable and growth parameters, i.e. maximum crop growth rate (Cm), maximum relative growth rate (Rm), and the lost time (tb) for expolinear growth equation using biomass data obtained from 4 experiments with different seasons [cut on Oct. and Nov. in 2004 (Expts. 1 and 2), and Apr. and Jun. in 2005 (Expts. 3 and 4)] and then to predict the crop growth based on an empirical model as a function of the environmental variable and plant density (plants/m2) using estimated parameters of the expolinear growth equation. The growth parameters were estimated by fitting the expolinear growth equation as a function of time, thermal units (TUs, °C·d), or daily incident photosynthetically active radiation (PAR, MJ·m−2·d−1) to observed the biomass per unit area (m2) using a nonlinear regression procedure with Gauss-Newton method. The use of TUs as a variable of expolinear growth equation improved the accuracy of the model and gave a better estimate of growth parameters as compared with those of time or incident PAR integral. Although the fitted expolinear growth equation effectively described the measured fresh and dry mass per unit area, we concluded that TUs was an appropriate variable of expolinear growth equation for single-stemmed rose ‘Vital’ considering some advantage, such as a cheap and easy way for growers to measure the microclimate inside a greenhouse for cut-flower rose production. This study also investigated the effects of TUs and plant density (67, 89, and 107plants/m2) on the growth of single-stemmed rose ‘Vital’ in a single stem system by adjusting the expolinear equation. The growth parameters, Cm, Rm, and tb were estimated by fitting the expolinear growth equation to the measured dry mass measurements obtained from 3 experiments (Expts. 1, 2, and 3) at three different plant densities. Parameters Cm and tb showed a curvilinear relationship with plant density over three experiments and were fitted to the quadratic function. The Rm was substituted with the mean value of the estimated values at each plant density, 0.0082, because there were no significant differences in Rm values among plant density treatments. The estimation of dry mass per unit area by the expolinear growth equation as inputs of TUs and plant density agreed well with the validation data, but the model tended to overestimate dry mass per unit area. The measured dry mass showed a linear relationship with fresh mass regardless of plant densities. The shoot fresh mass per m2 was estimated by an empirical relationship between shoot fresh mass and dry mass using the estimated shoot dry mass. The estimated and measured shoot dry mass and fresh mass showed a reasonably good fit with 1.142 (R2 = 0.988) and 1.168 (R2 = 0.976), respectively.

The scarcity of information on the demand of water for the cultivation of vegetables, such as lettuce, in protected environment, especially with regard to the adequate management of irrigation, limits productive performance. The objective of this study was to evaluate the effect of different irrigation slides on two cultivars of lettuce in protected environment. The experiment was conducted in Chapadinha - MA, from March to May 2017. The cultivars of lettuces used were Brava and cv. Grand Rapids-TBR, in a completely randomized experimental design with 5 treatments consisting of irrigation blades: 6,0, 12,0, 16,5, 19,5 e 31,8 mm corresponding to the tensions 6, 10, 15, 30, e 50 kPa, respectively, and five replications, totaling twenty five plots per cultivar. The following variables were analyzed: plant height, stem diameter, number of leaves, root volume, fresh shoot mass, shoot dry weight, fresh root mass, root dry mass and root length. For the cultivar Brava, the irrigation blade for tension of 50kPa, recorded the highest absolute yield of fresh and dry mass of the shoot, with averages of 65.99 g and 7.68 g, respectively. Likewise, for the cultivar cv. Grand Rapids-TBR, the 50 kPa strain also provided the highest numerical estimate for fresh and dry shoot mass, 129.09 g and 51.03 g, respectively. The blades corresponding to the tensions of 6 and 10kPa, consumed about 18 mm per plant more than the tension of 50 kPa, for both cultivars. In an equivalent way, the fresh mass of the aerial part had greater increase in the tension of 50 kPa (65.99 g).

The present project aimed to evaluate the initial development of wheat ( Triticum spp.) under different nitrogen dosages. The experiment was carried out in the experimental area of the Fronteira Sul Federal University - Campus Chapeco . The experimental design was a randomized block (DBC) with four treatments and five replications, corresponding to 20 experimental units, each one being represented by a vessel. The treatments were: T1 - control (0,0 mg / dm³), T2 - 80,00 mg / dm³, T3 - 200,00 mg / dm³ and T4 - 400,00 mg / dm³ of nitrogen (source urea). Nitrogen fertilization was applied at 13 and 20 days after emergence - DAE. The variables analyzed were: number of leaves and tillers, plant height, fresh mass and shoot and root dry mass. The evaluation of the number of leaves and tillers, plant height and fresh shoot and root mass were performed at 51 DAE. From the values obtained for shoot and root dry mass the relation shoot/ root was obtained. Shoot and root dry mass were also determined with 51 DAE plants, after drying in an oven of 60oC. To measure the height of plants, a tape measure was used and precision balance were used to determine the masses. The addition of N significantly improved the root and shoot dry mass and the number of leaves and tillers. Therefore, it is an essential element for the development of the wheat crop. The best wheat performance, for the different response variables, occurred between the dosages of 230 to 400 mg dm³ of nitrogen.

Residues of crops and cover crops contain considerable amounts of phosphorus (P) in their tissues, which through their mineralization can meet much of the requirement of crops. In this context, the present study aimed to evaluate the biomass production, P absorption and use of different cover crops subjected to phosphate fertilization, and its effects on the absorption and use of nitrogen (N), phosphorus (P) and potassium (K). The experiment was conducted in a protected environment from August to December 2019. The experimental design was completely randomized, arranged in a 7 x 3 scheme, consisting of the planting of seven species of cover crops (Crotalaria spectabilis, Crotalaria breviflora, Crotalaria ochroleuca, Mucuna aterrima, Mucuna pruriens, Dolichos lablab and Canavalia ensiformis), three P rates (0, 80 and 160 kg ha-1 of P2O5) and four replicates. At the time of full flowering, the cover species were cut and divided into root and shoot for subsequent determination of dry mass production, nutrient content and absorption efficiency and nutrient utilization. The results showed that Canavalia ensiformis promoted higher yield of shoot fresh and dry mass, P content in the shoots and higher N and P absorption efficiency. N and P contents in Dolichos lablab roots were higher at the highest P rates (160 kg ha-1 of P), without close relationship with the supply of shoot dry mass. The P dose of 160 kg ha-1 had an increasing and significant effect on the production of shoot fresh mass and dry mass, N, P and K contents in the shoots, N, P and K contents in the roots and efficiency of N, P and K use by the different cover crops. The P rates of 80 kg ha-1 increased the N, P and K contents in the shoots of Crotalaria ochroleuca, Crotalaria breviflora and Crotalaria spectabilis; and at higher P rates, there was a reduction in nutrient accumulation. The species Mucuna pruriens and Mucuna aterrima were efficient in the use of N, P and K at P rates of 160 kg ha-1.

Bush tea (Athrixia phylicoides) belongs to the Asteraceae family. It is a popular beverage used as an herbal tea and as medicine for cleansing or purifying the blood, treating boils, headaches, infested wounds, and cuts, and the solutions may also be used as a foam bath. In some parts of South Africa, people drink bush tea for aphrodisiac reasons. Bush tea was grown under varying N, P, and K levels in all four seasons to determine the seasonal nutrient requirements for improved plant growth. Three parallel trials for N, P, or K one at each season were laid out in a randomized complete block design (RCBD) with six treatments replicated eight times. Treatments consisted of 0, 100, 200, 300, 400, or 500 kg·ha–1 N, P, or K. Parameters recorded were plant height, number of branches and leaves, fresh and dry stem mass, fresh and dry root mass, stem girth, fresh and dry shoot mass, leaf area and percentage leaf and root tissue N, P, and K. Results of this study demonstrated that, in all trials regardless of season, N, P, or K nutrition increased bush tea fresh and dry shoot mass, plant height, number of leaves, number of branches and leaf area. Regardless of season, the optimum level of N, P and K fertilization for bush tea on growth parameters was 300 kg·ha-1 N or P and 200 kg·ha-1 for K. No significant differences in number of flowers and buds (fall and winter), stem girth, fresh and dry root mass as well as fresh and dry stem mass were obtained.

The present study aimed to evaluate the initial development of safflower genotypes (Carthamus tinctorius) after different periods of seed hydration. For the study two experiments were evaluated. At first, an experiment was performed with 0, 24, 48, 72, 168 and 360 hours of seed hydration, and in the second moment, another with 0, 12, 24, 36, 48 and 60 hours of hydration. The experimental design for the two experiments was completely randomized, with four replicates and six treatments. After 30 days of conduction of the experiments were analyzed the percentage of emergency, index of emergency speed, average time of emergency and average speed of emergency. The evaluated morphological characteristics were plant height, stem diameter, root length, fresh shoot and root mass and dry shoot mass. Hydration of seeds in considerable proportions positively influences the emergence and development of safflower plants. The highest performance in the emergence of plants, size, accumulation of fresh and dry shoot mass and fresh root mass was obtained by the IAPAR genotype, which stood out in relation to the other. The greatest emergencies were obtained with seeds with 36 hours of hydration, and the lowest emergence was found after 72 hours under hydration.

Objective: To evaluate under controlled conditions the effect of alternative liquid Bacillus subtilis isolate 34 formulation on Meloidogyne javanica and tomato growth promotion.
 Statistical Design: The design was completely randomized block with five treatments and eight replicates. The results were submitted to the analysis of variance and the averages compared by the Tukey test with 5% error probability. The statistical package used in the analysis of the data was the program "Sisvar"
 Location and Duration of the Experiment: The experiment was set up during the period from February 13, 2018 to April 20, 2018 in greenhouse located at the State University of Montes Claros, municipality of Janaúba, MG, Brazil.
 Methods: Treatments consisted of different times of application of bacteria in tomato seedlings: application of bacteria in the tube at eight and fifteen days after emergence; application of bacteria in the tube at eight and fifteen days after emergence and in pots at 25 and 35 days after transplanting; application of bacteria at 25 and 35 days after transplantation in the pot; Onix® commercial product (Bacillus methylotrophicus-UFPEDA20) and control. After 60 days of transplanting, the number of egg masses, number of galls, number of eggs, number of second-stage juveniles (J2) and reproduction factor, height, fresh and dry shoot mass and fresh root mass of tomato plants were evaluated.
 Results: There was a reduction in the number of J2, eggs pre root, and eggs per gram of root when the bacteria formulation was applied in the tube + pot and in pot only. The application of the bacteria in the tube + pot and in only pot only presents the highest increase of fresh and dry shoot mass and fresh root mass.
 Conclusion: The application of the liquid B. subtilis isolated 34 formulation to the soil in the pot and tube + pot reduced the reproduction of M. javanica and promoted greater tomato development.

The objective of this study was to evaluate combinations of coriander and salad rocket cultivars in bicropping systems intercropped with carrot cultivars in strips under the conditions of Mossoró-RN. The work was conducted at the Experimental Farm Rafael Fernandes from July to December 2014. The experimental design was a randomized complete block design with four replications and treatments arranged in a factorial design with additional treatments of type 2 x 2 x 2 + 2. The treatments consisted of the combinations of two coriander cultivars (Verdão and Português) and two rocket cultivars (Cultivada and Folha Larga), intercropped with two carrot cultivars (Brasília and Esplanada) plus two additional treatments, where the first are the cultivars in monocropping and the second the types of cropping (single and intercropped). We evaluated fresh and dry shoot mass in coriander and rocket and fresh and dry shoot mass as well as dry root mass, commercial and total root productivity, and classified root productivity in carrot. In the intercropping systems we evaluated land equivalent ratio, productive efficiency index, and score of the canonical variable, besides the indicators of economic efficiency (gross income, net income, rate of return and profit margin). Highest agroeconomic efficiency in intercropping systems was achieved with the combination of the coriander cultivar 'Verdão' and the rocket cultivars 'Folha Larga' or 'Cultivada' as well as the carrot cultivars 'Brasília' or 'Esplanada'. Regardless of the tested cultivar combinations, systems with coriander and salad rocket intercropped with carrot showed higher efficiency than monocropping systems.

The growth of plants by the use of Trichoderma occurs through distinct mechanisms, among which it can highlight the synthesis of phytohormones and auxins analogues. The objective of this work was to evaluate Trichoderma spp. commercial strains in the promoting seedlings growth and in the productivity of parsley plants. In laboratory assay, seeds of parsley cv. ‘Graúda Portuguesa’ were treated with 2 mL of Trichoderma suspension (2.5 × 108 ml-1 conidia per 100 g of seeds) submitted to growth test until 28 days after sowing (DAS). For the greenhouse experiment, parsley seedlings were transplanted into 3.0 L pots containing soil, which was previously treated with 5 mL Trichoderma suspension, totaling 1.5 × 108 conidia per pot. In both, a control without Trichoderma application was included, being arranged in a completely randomized design (CRD). The evaluations were: percentage of germination (PG), root length (RL), shoot length (SL), total length (TL = RL + SL), fresh root mass (FRM), fresh shoot mass (FSM), total fresh mass (TFM = FRM + FSM), root dry mass (RDM), shoot dry mass (SDM), total dry mass (BIO = RDM + SDM), root mass ratio (RMR = RDM/BIO), shoot mass ratio (SMR = SDM/BIO), aerial part/root system retio (AP/RS = SDM/RDM) and productivity at 110 DAS. Althougth no diferences was observed among the Trichoderma treatments and the control about yield, Trichoderma spp. strains provided better TFM (18.98 to 22.92 mg), BIO (3.37 to 4.31 mg) and root system superior to the control (14.20 and 2.44 mg, respectively) under greenhouse conditions. T. harzianum ESALQ1306 was the better strain in laboratory assyas, suggsting this isolate for applied in the seeds when it aims the promotion of initial growth.

The effect of low initial medium pH on shoot and root development of five white poplar (Populus alba L.) genotypes was tested. The shoot height, fresh mass of shoots per jar, dry mass of shoots per jar, number of roots, as well as the length of the longest root were measured and final pH of the media determined, after 35 days of culture in vitro. Three initial pH values of the medium were tested: 3.0, 4.0 and 5.5 as control. Agar solidification at pH 3.0 was not achieved after sterilization in autoclave, but it was successful after sterilizing in a microwave oven. The obtained results indicate that the tested genotypes are able to significantly influence the changes of media pH during culture. The effect of differences among the examined media was significant for biomass accumulation and final media pH. Generally, significantly higher values of fresh and dry shoot mass, shoot height and the longest root length were recorded on a medium with initial pH 3.0 then on a standard medium with pH 5.5.The implications of the obtained results for the improvement of in vitro propagation of white poplars are discussed.

Increasing urbanisation and the rise in global food prices, which results in severe hunger and micronutrient deficiencies, necessitates the identification of innovative, but affordable vegetable growing-based strategies, that can increase access to food by utilising the limited space available in rural and urban areas. Therefore, sack gardening technology could be a solution to both the lack of arable land and water scarcity in urban and rural areas. The objective of the study was to determine whether axillary bud number will have an effect on the agronomic parameters of sweet potato cv. 'Blesbok' produced using the sack gardening technology. The number of axillary buds per stem cutting, namely, 1 (control), 2, 3, 4, and 5 buds, were arranged in RCBD, with 10 replicates. The number of axillary buds had significant effects on vine length (VL), fresh shoot mass (FSM), number of shoots (NOS) and dry shoot mass (DSM). However, no significant effects were observed on fresh tuberous root mass (FTRM), chlorophyll content (CC), stem diameter (ST), tuberous root diameter (TRL), tuberous root length (TRL), dry tuberous root mass (DTRM) and number of tuberous roots (NTR). Relative to the control VL, FSM and DRM was reduced by 8-37, 30-55 and 26-55%, in stem cuttings having 2, 3, 4 and 5 buds, respectively, whereas the NS was increased by 8-17%. The quadratic relationship models were explained by 95, 92, 96 and 98% in VL, NOS, FSM and DSM, respectively. In conclusion, stem cuttings containing 1 and 2 axillary buds showed better growth parameters when grown under sack gardening technology.

As plantas daninhas competem direta e indiretamente com a cultura da cana-de-açúcar, prejudicando sua produção. Desta forma, controlar estas plantas daninhas é de grande importância para atingir elevadas produtividades. O manejo químico de plantas daninhas é um dos métodos mais eficientes, entretanto, dependendo da forma como os herbicidas são aplicados, podem causar injúrias a cultura. Portanto, conhecer o efeito fitotóxico que a aplicação de herbicidas pode ocasionar em mudas pré-brotadas se faz necessário. Assim, o objetivo deste trabalho foi avaliar a eficácia e seletividade de associações de herbicidas inibidores da protox e do fotossitema II em pós-transplante de mudas pré-brotadas de cana-de-açúcar, quando comparados com outras associações de herbicidas praticadas pelos produtores de cana-de-açúcar. Foram realizados dois projetos, sendo o primeiro em casa-de-vegetação, seguindo o delineamento inteiramente casualizado, com quatro repetições e esquema fatorial 10 x 2, onde o primeiro fator correspondeu aos tratamentos (testemunha; (sulfentrazona + diurom) (525,0 + 1050,0); (sulfentrazona + diurom) (700,0 + 1400,0); (sulfentrazona + diurom) (875,0 + 1750,0); (sulfentrazona + diurom) + mesotriona (700,0 + 1400,0 + 120,0); diclosulam + tebutiurom + ametrina (70,6 + 750,0 + 1500,0); diclosulam + s-metolacloro + ametrina (70,6 + 2400,0 + 1500,0); 2,4-D (1005,0) para as dicotiledôneas e metribuzim (1920,0) para as monocotiledôneas; MSMA + ametrina (1185,0 + 1500,0) e flumioxazina + tebutiurom (125,0 + 750,0), doses em g i.a. ha-1) e o segundo a duas épocas de aplicação (pós-inicial (2 a 4 folhas/1 a 2 perfilhos) e pós-tardia (6 a 8 folhas/3 a 4 perfilhos)). Este esquema foi realizado em 11 experimentos independentes, sendo um para cada planta daninha estudada (Luffa aegyptiaca; Ipomoea hederifolia; Merremia aegyptia; Ricinus communis; Momordica charantia; Mucuna aterrima; Digitaria nuda; Rottboellia exaltata; Brachiaria plantaginea; Brachiaria decumbens e Panicum maximum). As unidades amostrais foram compostas por vasos de 3,0 L preenchidos com solo de textura argilo-arenosa e as plantas daninhas foram semeadas de acordo com recomendação da empresa. Após semeadura das plantas daninhas, os vasos foram mantidos em casa-de-vegetação com irrigação. Quando as plantas daninhas atingiram os estádios fenológicos necessários foi realizada aplicação com pulverizador costal pressurizado a CO2. As avaliações de controle foram realizadas aos 7; 14; 21; 28; 35 e 42 dias após aplicação (DAA), seguindo escala visual de notas proposta pela ALAM (1974). Aos 42 DAA foi realizada avaliação de massa seca da parte aérea, cortando as plantas remanescentes rentes ao solo, colocando em sacos de papel e levando para estufa de circulação de ar até atingirem peso constante. Os dados obtidos foram analisados pelo Teste F a 5,0% e, quando significativos, pelo Teste de Scott-Knott também a 5,0%. Já o segundo projeto foi conduzido em campo, em duas safras (2018/2019 e 2019/2020), seguindo o delineamento de blocos casualizados, com 4 repetições e 14 tratamentos (testemunha sem capina; testemunha capinada; (sulfentrazona + diurom) (612,5 + 1125,0); (sulfentrazona + diurom) + clomazona (525,0 + 1050,0 + 1080,0); (sulfentrazona + diurom) (700,0 + 1400,0); (sulfentrazona + diurom) (875,0 + 1750,0); (sulfentrazona + diurom) + mesotriona (700,0 + 1400,0 + 120,0); s-metolacloro + mesotriona + (hexazinona + diurom) (2400,0 + 120,0 + 200,0 + 1600,0); s-metolacloro + mesotriona + metribuzim (2400,0 + 120,0 + 1440,0); s-metolacloro + mesotriona + atrazina (2400,0 + 120,0 + 1500,0); clomazona + mesotriona + (hexazinona + diurom) (1080,0 + 120,0 + 200,0 + 1600,0); clomazona + mesotriona + metribuzim (1080,0 + 120,0 + 1440,0); s-metolacloro + mesotriona + metribuzim + tebutiurom (2400,0 + 120,0 + 1440,0 + 1000,0) e flumioxazina + tebutiurom (125,0 + 1000,0), doses em g i.a. ha-1). Este esquema foi realizado para as duas safras avaliadas. As unidades amostrais foram parcelas de 60,0 m2 transplantadas com MPBs da cultivar RB966928. A aplicação dos tratamentos foi realizada 30 dias após o transplante das mudas, realizado com pulverizador costal pressurizado a CO2. Foram realizadas avaliações de controle, de fitotoxicidade, de altura, número de perfilhos, número de gemas, produtividade e brotação de gemas. As avaliações de controle das plantas daninhas e da fitotoxicidade da cultura ocorreram aos 7; 15; 30; 45; 60; 90 e 120 dias após aplicação (DAA), seguindo escalas propostas pela ALAM (1974) e EWRC (1964), respectivamente. As avaliações de altura e número de perfilhos aconteceram aos 15; 45; 90 e 300 DAA. As avaliações de número de gemas e produtividade aos 300 DAA e a avaliação de brotação das gemas aos 3; 7; 15 e 30 dias após plantio das gemas (DAP). Os dados obtidos também foram analisados pelo Teste F a 5,0% e, quando significativos, pelo Teste de Scott-Knott também a 5,0%, através do programa estatístico AgroEstat®. Com relação ao controle das plantas daninhas, observou- se que as associações de herbicidas inibidores da protox e do fotossistema II (sulfentrazona + diurom e flumioxazina + tebutiurom) foram eficazes no controle de todas as plantas daninhas avaliadas, quando aplicados em pós-emergência inicial, promovendo porcentagens de controle superiores a 80,0%. Já quando a aplicação ocorreu em pós-tardia, o controle foi menos eficiente para todas as plantas daninhas. Com relação a seletividade destas associações as MPBs da cultivar RB966928, constatou-se que foram seletivas, não impactando negativamente nas variáveis altura, número de perfilhos, número de gemas, produtividade e, também, brotação de gemas após colheita. Conclui-se, portanto, que as associações de herbicidas inibidores da protox e do fotossistema II (sulfentrazona + diurom e flumioxazina + tebutiurom) são ferramentas eficientes para controle de plantas daninhas em cana-de-açúcar e são seletivas as MPBs quando aplicados 30 dias após o transplante das mesmas.

The fungus Trichoderma spp. is known due to its versatility for promoting crop growth and grain yield, improving the nutrient absorption and increasing the grain yield. The objective of this work was to evaluate commercial strains of Trichoderma spp. and an organomineral fertilizer in the early growth promotion and grain yield of wheat plants. Thus, wheat seeds cv. BRS 264 were treated with 2 mL of a Trichoderma suspension (2.5 × 108 conidia mL-1 per 100 g seed) and submitted to growth in laboratory until 8 days after sowing (DAS). In the greenhouse experiment, the seeds were sown in an 8 L pot, which received 4.0 × 108 conidia of Trichoderma per pot. In both evaluations were: percentage of germination (PG), root length (RL), shoot length (SL), total length (TL), fresh root mass (FRM), fresh shoot mass (FSM), total fresh mass (TFM), dry root mass (DRM), dry shoot mass (DSM), total biomass (BIO), root mass ratio (RMR), shoot mass ratio (SMR) and aerial part/root system ratio (AP/RS). In the greenhouse experiment, paniculation and grain yield were evaluated at 110 DAS. The treatments T. harzianum ESALQ 1306 and T. asperellum URM5911 were considered satisfactory, since they provided grain yield superior to 2,000 kg ha-1. In addition, T. harzianum ESALQ 1306 provided the best results for PG, RL, SL, TL, FRM, FSM, TFM, DRM, DSM and BIO under greenhouse conditions. The reduced biomass allocation to the root system in seedlings treated with Trichoderma ssp. occurred in the laboratory, which was confirm in greenhouse.

The objective of this study was to evaluate the photosynthetic and physiological parameters of soybean plants under water deficit after imbibition in different concentrations of salicylic acid during germination. The initial seed quality of the cultivar Bayer®/Tec Irga 6070 RR was evaluated. The soybean seeds were soaked in 25 ml in the salicylic acid solution (SA) for 24 hours and the retention capacities of 30, 50 and 70% were adopted. Under controlled conditions, concentrations of zero, 250, 500, 750 and 1000 µM, evaluating the variables length, fresh and dry mass of root and shoot. In the greenhouse, the concentrations of SA of zero, 500 and 1000 µM were used. After 29 days of the seedling, the stomatal conductance, length, fresh and dry mass of root and shoot were evaluated. The results showed that the uptake of SA in the germination aided seedlings under water deficit. The retention capacity of 30% simulated the water deficit, damaging the physiological parameters of soybean seedlings in both environments. The concentrations of 500 and 1000 µM of SA were efficient in the water deficit for the variables root length, fresh and dry shoot mass.

One of the problems in modern agriculture is the residue of herbicides in the succession of crops, mainly the corn crop in sequence to the culture of the soybeans, better known as corn crop. Succession is a common practice of grain production systems, aiming to maximize yields of the properties, and some practices adopted in the management of the summer crop can directly affect the subsequent crop. The objective of this research was to evaluate the residual effect of the herbicide imazethapyr on the cultivation of soybeans in pre-emergence or desiccation on maize cultivation in succession in its initial stages.It was a trial with 5 treatments and 4 replications in a completely randomized design, involving different corn sowing times: 90, 105, 120 and 135 days after application(DAA) of the herbicide imazetapir, and a control treatment without the application of the herbicide. Percentage of phytotoxicity was analyzed at 7, 14, 21 and 28 days after sowing (DAS), seedling emergence velocity, shoot dry mass and root weight at 28 DAS. The treatments sown with 90 and 105 DAA showed a phytotoxicity effect in all the evaluations, also presenting lower weight of shoot and root dry mass, thus demonstrating the residual effect and influence of the herbicide on the crop up to 105 DAA. Regarding the emergence of seedlings, the treatments did not differ.