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Abstract Background Seed conditioning with bioinputs (biopriming) offers a promising and sustainable alternative to mitigate the adverse effects of salt stress on soybeans. This study aims to evaluate the potential of isolated or combined biopriming using microalgae and different microorganisms in alleviating salinity-induced stress in soybeans in early-stage. Methods Seeds were subjected to five biopriming treatments: Parachlorella sp. microalgae culture, Bacillus subtilis, Trichoderma harzianum, Parachlorella sp. + B. subtilis, and Parachlorella sp. + T. harzianum, along with a control group without biopriming. Subsequently, the seeds were exposed to two conditions: (i) control (0.0 MPa), and (ii) salinity induced by NaCl (-0.8 MPa). Germination, photochemical indicators, and seedling performance were assessed. Results Salinity impaired root protrusion and seed physiology, resulting in a high percentage of abnormal seedlings, thus creating a stressful condition. However, biopriming alleviated the negative effects of salinity, particularly with T. harzianum, Parachlorella sp. + B. subtilis, and Parachlorella sp. + T. harzianum, which led to high germination rates and normal seedlings. All biopriming treatments, especially the combined ones, reduced the suppression of non-photochemical quenching, thereby enhancing the maximum yield of photosystem II. Seedlings under salt stress without biopriming exhibited short lengths and low fresh and dry mass, whereas those bioprimed with Parachlorella sp. + B. subtilis and Parachlorella sp. + T. harzianum showed significantly higher values. Conclusion Seed biopriming, especially with Parachlorella sp. microalgae culture combined with B. subtilis or T. harzianum, effectively alleviates the stressful effects of salinity on germination and early-stage growth seedling of soybeans.

Abstract: Guava is one of the fruit trees with good economic returns. The aim with this study was to evaluate the production and fruit quality of five guava cultivars (Tailandesa, Cortibel SLG, Cortibel RM, Cortibel RG, and Paluma) submitted to staggered and continuous production pruning, in the bioclimatic conditions of Southwest Mato Grosso do Sul. The experiment was conducted during the year 2019/2020/2021, performing two production pruning (PP1 and PP2). In each production pruning, eight fructification pruning were carried out, with an interval of 30 days, namely: in PP1 (October/2019, November/2019, December/2019, January/2020, February/2020, March/2020, April/2020 and May/2020); and in PP2 (June/2020, July/2020, August/2020, September/2020, October/2020, November/2020, December/2020 and January/2021). Statistical analyzes were performed within each production period, not comparing the effects of these. The means were compared using the Tukey test for cultivars and the Scott-Knott test for staggered pruning. Higher yield values were observed in PP1 of the Tailandesa and Cortibel RM cultivar, in the pruning of October/2019 and January/2020. In PP2, the productivity of all cultivars was higher than in PP1, especially Cortibel RM and Tailandesa, with higher yields and lower amounts of non-marketable fruits in the pruning of November and December/2020 and January/2021. The fruits were classified as oblong and with quality for commercialization. Continuous staggered pruning, and Tailandesa and Cortibel RM cultivars are promising for cultivation in Southwest MS.

ABSTRACT Using organic residues and bioinputs is a promising and sustainable practice to produce seedlings with forest essences, such as Cedrela fissilis Vell. (cedar), a vulnerable species close to extinction due to intensive exploitation in native areas. Thus, we aimed to evaluate the effect of different substrates based on organic residues associated with or without the application of Parachlorella sp. microalgae in the emergence and morphophysiology of C. fissilis seedlings. Sowing was carried out on six substrates: Oxisol with a clayey texture; Oxisol + Parachlorella sp.; Oxisol with sheep manure (3:1, v v–1); Oxisol with sheep manure + Parachlorella sp.; Oxisol with cattle manure (3:1, v v–1); and Oxisol with cattle manure + Parachlorella sp. The addition of organic residues to the soil, especially cattle manure, contributes to increasing the percentage of emergence, plant height, chlorophyll index, CO2 assimilation rate, and instantaneous carboxylation efficiency of Rubisco due to the superior chemical attributes in the substrate, which promote greater physiological efficiency. Organic residues increased the water use efficiency of seedlings. The application of Parachlorella sp. microalgae contributes to increases in the CO2 assimilation rate and stomatal conductance when seedlings are grown only in Oxisol. C. fissilis seedlings produced in the substrate with sheep and cattle manure showed better growth and gas exchange characteristics.

Plant responses to different light and water availability are variable among species and their respective phenotypic plasticity, and the combination between these two abiotic factors can alleviate or intensify stressful effects. This study aimed to evaluate the impacts of exposure time of Cedrela fissilis Vell. seedlings to different water and light availability considering natural radiation variations and the interaction of these factors. Seedlings were submitted to combinations of three shading levels—SH (0, 30 and 70%) and three water regimes based on the water holding capacity (WHC) in the substrate, constituting nine cultivation conditions: T1—0% SH + 40% WHC; T2—0% SH + 70% WHC; T3—0% SH + 100% WHC; T4—30% SH + 40% WHC; T5—30% SH + 70% WHC; T6—30% SH + 100% WHC; T7—70% SH + 40% WHC; T8—70% SH + 70% WHC; T9—70% SH + 100% WHC. C. fissilis seedlings are sensitive to water deficit, here represented by 40% WHC, regardless of exposure time, and when cultivated in full sun even though there are variations in radiation, the stressful effects were enhanced, acting in a synergistic manner. The condition that provided better gas exchange performance and greater total dry mass accumulation for C. fissilis seedlings was 30% shading combined with 100% WHC. C. fissilis seedlings have physiological plasticity and resilience to survive under different water and light conditions.

ABSTRACT Light stress damages the photochemical apparatus and affects seedling growth of forest species. Using potassium silicate (K2SiO3) can mitigate these deleterious effects and contribute to the acclimatization and robustness of seedlings. This study evaluated the effect of K2SiO3 and shading levels on the photochemical and growth of Alibertia edulis (Rich) A. Rich seedlings. The experiment was arranged under three light conditions based on shading levels of 0 % (full sun), 30 %, and 70 %. Four doses of K2SiO3 applied through foliar spray were tested: 0.0, 2.5, 5.0, and 10.0 mL L–1. Cultivation under full sun and under 70 % of shade was stressful for A. edulis, while cultivation under 30 % of shade improved plant growth. Increasing application of K2SiO3 in seedlings under full sun damaged the reaction center, causing lower photochemical yields, but increased the photochemical efficiency of photosystem II under 30 % of shade. Using K2SiO3 contributed to leaf water regulation while applying 10.0 mL L–1 increased chlorophyll indices, leaf area, physiological indices, and the quality of seedlings cultivated under full sun and 30 % of shade. Using 10.0 mL L–1 K2SiO3 mitigated the negative effects of light stress under full sun. It provided high photochemical efficiency, morphology aspects, and Dickson quality index A. edulis seedlings in environments with high or moderate light availability.

ABSTRACT: In order to establish protocols that can contribute to the propagation of medicinal plants, this study evaluated the effect of hydropriming and substrates on the emergence and production of Calendula officinalis L. seedlings. Seeds were submitted or not to hydropriming for 24 hours, and subsequent sowing in four substrates: S1) 100% Dystroferric Red Latosol - DRL, S2) DRL + coarse sand (1:1 v/v), S3) DRL + Tropstrato® commercial substrate (1:1 v/v) and S4) 100% Tropstrato®, and kept in greenhouse with 50% shading. Higher emergence percentage in substrates with the presence of DRL was observed. Seed hydropriming impaired seedling emergence, but contributed to root growth, biomass production and seedling quality. The 100% Tropstrato® substrate favored higher dry mass production and seedling quality. Positive linear correlation (≥ 0.70) was observed between shoot and root growth characteristics with biomass production and Dickson’s quality index. Principal component analysis explained 78.95% of the experimental variance, excluding the first count and the shoot/root ratio with low representativeness. In the cluster analysis of Euclidean distances, seedlings with the greatest similarity were those produced with 100% DRL and DRL + Tropstrato® with and without hydropriming, respectively. Dystroferric Red Latosol is recommended pure or combined with Tropstrato® for the production of C. officinalis L seedlings, and the hydropriming impaired seedling emergence characteristics.

Water deficit is one of the factors that most influence plant growth and yield. Thus, this study aimed to evaluate the effect of silicon and salicylic acid application and water deficit on the growth and photosynthetic and osmoregulatory metabolism of Talisia esculenta Radlk. seedlings and their recovery potential after the resumption of irrigation. Six treatments were performed: irrigation, irrigation suspension, irrigation suspension + silicon at 0.5 g L−1, irrigation suspension + silicon at 1.0 g L−1, irrigation suspension + salicylic acid at 50 mg L−1, and irrigation suspension + salicylic acid at 100 mg L−1. The evaluations were carried out at the beginning of the experiment, at 10 and 15 days after irrigation suspension, when the seedlings showed a photosynthetic rate close to zero, and at recovery. The plants were subjected to water restriction for up to 15 days, then re-irrigated until the recovery point, which was monitored based on the photosynthetic rate. Silicon application attenuated the harmful effects of water deficit on gas exchange and initial fluorescence, promoted proline accumulation in the leaf and root, and provided higher seedling quality. Salicylic acid application contributed to the maintenance of the relative water content of leaves during the water deficit period. Silicon and salicylic acid applications can attenuate the harmful effects of water stress, with silicon being the most effective agent in maintaining its growth and metabolism.

Abstract This study aimed to evaluate the potential of shading in reducing the stressful effect of water restriction on photosynthetic and antioxidant metabolism, favoring the growth of Ormosia arborea seedlings and the recovery metabolic. The shadings levels studied were: 0, 30 and 70%. Two water regimes were implemented: control, in which the plants were irrigated at 75% of soil water retention capacity and water restriction, in which the irrigation was suspended until the photosynthetic rate reached values close to zero (P0), period at which the seedlings were re-irrigated. There were two evaluation periods: P0 and recovery. We observed that water restriction reduced photosynthetic metabolism, growth and quality of O. arborea seedlings by increasing the activity of antioxidant enzymes. The seedlings present higher quality index, stomatal conductance, intrinsic carboxylation efficiency and transpiration when cultivated under 70% shading in recovery. The stressful effect of water restriction was mitigated by the shading of 70%, where the seedlings were able to recover, resuming their photosynthetic metabolism and quality after resumption of irrigation. In addition, 0% shading is not indicated for this species.

Abstract The cultivation of blackberry trees has been increasing in Brazil, making it necessary to establish management and crop treatments in order to enhance its production. The aim of this study is to evaluate the production and quality of blackberry fruits cv. ‘Tupy’ regarding pruning seasons and trellis systems in the Southwest region of Mato Grosso do Sul. The experiment was developed with evaluations in two production cycles (2013 and 2014). Three trellis systems were studied: C1 – Double-wire trellis, C2 – single-wire trellis, and C3 – ‘T’ trellis; and the following three winter pruning times in both production cycles: P1: 07/12; P2: 07/27; and P3: 08/11. Production performances were similar within each year. In 2013, the harvest period ranged from 10/22/2013 to 01/07/2014, while in 2014 the period ranged from 09/24/2014 to 12/12/2014. In 2014, the highest fruit production per plant occurred when P3 was performed. Cultivation using the Double-wire trellis system (C1) produced 11,669.43 and 3,465.98 kg, while the single-wire trellis system (C2) produced 11,965.53 and 3,373.87 kg in 2013 and 2014, respectively. The highest pH of fruits was observed when pruning was conducted in P1 using the ‘T’ trellis system. Double-wire trellis contributes in higher results of production blackberry in the Southwest region of Mato Grosso do Sul.

Abstract This study aimed to evaluate the effect of exogenous application of salicylic acid on the photosynthetic metabolism and quality of Eugenia myrcianthes seedlings under water deficit and their recovery potential after rehydration. Two water regimes were evaluated, as follows: control - plants irrigated daily (I) and water deficit (S), with and without the application of 400 mg L–1 of salicylic acid (SA), totaling four treatments. Seedlings were evaluated at three times: at the beginning of the experiment (T0), that is, when the irrigation was interrupted; when the photosynthetic rate reached values close to zero (P0 - 15 days after irrigation interruption), that is, when irrigation restarted; and when the photosynthetic rate was recovered (REC). Eugenia myrcianthes seedlings were negatively affected when subjected to water restriction; salicylic acid attenuated the damage to the photosynthetic apparatus by acting positively on the relative water content in the leaves, SPAD index, photosynthetic metabolism, superoxide dismutase and peroxidase enzyme activity, and seedling growth in P0. Eugenia myrchiantes presented potential for recovery after resumption irrigation. The application of SA contributed to the maintenance of gas exchanges, photochemical processes and quality of E. myrcianthes seedlings during and after water deficit, suggesting the promotion of plant resistance induction.

Abstract The aim was to evaluate the effect of chicken manure and substrate liming in the Campomanesia xanthocarpa (‘gabiroba’) physiology, nutrition and growth. Five dosages of chicken manure (0; 5; 10; 15 and 20 Mg ha-1) were studied without and with substrate liming. The treatments were arranged in a 5 x 2 factorial scheme, in a randomized block design with four replications. There was an improvement on the chemical attributes in the substrate and nutrients contained in the plants where liming was performed. The highest plant height of C. xanthocarpa occurred with liming and 9.03 Mg ha-1 of chicken manure. The diameters were liming-grown plants and 4.57 mm with 5 Mg ha-1 of chicken manure. The photochemical efficiencies of PSII occurred in plants grown on liming substrate. It was concluded that C. xanthocarpa plants had their development optimizes with substrate liming and incorporation of 5 Mg ha-1 chicken manure.

Abstract The aim this study was to evaluate the effect of salicylic acid (SA) in Schinus terebinthifolia seedlings subjected to irrigation intervals. The experiment was performed by 78 days, under four irrigation intervals: 0, 4, 8, and 12 days, in combination with four concentrations SA: 0, 50, 100, and 200 mg L-1. The irrigation was individually maintaining water retention capacity of 100%, under each irrigation intervals. The maximum height across the irrigation intervals was 24.74 cm at 7-days intervals, and 24.31 cm with 200 mg L-1 of SA. The largest leaf areas were 116.03 cm2 at 12-day interval and 123.71 cm2 with 200 mg L-1 of SA. The highest production of dry masses of leaves, stem and roots was without and 12-days intervals, both with 200 mg L-1 of SA. Exogenous application of 200 mg L-1 of SA contributed on increased growth in S. terebinthifolia seedlings subjected to 12-days irrigation interval.

Abstract It is essential to know the ecological tolerance of Anadenanthera peregrina (L.) Speg seedlings regarding the light and edaphic conditions. The aim of this study was to evaluate the effect of substrates and shading levels on the emergence and quality of A. peregrina seedlings. The seeding was done in two substrates: 100% Dystroferric Red Latosol (DRL) and DRL + commercial substrate (1:1, v/v). The species were kept under four shading levels: 0% (direct sunlight), 30%, 50% and 70%. The highest speed and shortest emergence time of A. peregrina occurred in DRL. The highest growth characteristics of aerial part, xylopodium and roots occurred under direct sunlight and DRL. The productions of fresh and dried masses of different vegetative organs, physiological and Dickson quality index were higher in DRL and direct sunlight. The A. peregrina seedlings in 100% of DRL and direct sunlight showed more viable morphophysiological and quality indicators for their production.

Abstract The aim of this study was to evaluate the use of different organic residues and bokashi in the substrate formulation in the initial growth of marmelo-do-cerrado. The experiment was carried out in pots under shading (50%). The following organic residues were tested: poultry manure (PM) with rice husk base, PM with wood shavings base, Organosuper®, and castor bean meal, in a control with only soil. All treatments were assessed with and without bokashi. The experimental arrangement was a 5 × 2 factorial scheme in a randomized block design with four replicates and four plants. The greatest plant height was observed when the plants were cultivated in PM with rice husk base with bokashi. The pigment contents, photochemical efficiency, biomasses and quality of seedlings were highest in Organosuper® with bokashi. We recommend the use of Organosuper® and PM with rice husk base, both with bokashi, in the growth of marmelo-do-cerrado.

Na busca de um desenvolvimento sustentável, a Agroecologia é uma ciência que articular todos os recursos presentes no ambiente. Porém, muitos ainda desconhecem a mesma, sendo de suma importância sua difusão através de concepções pedagógicas. Desta forma, objetivou-se com este trabalho articular o diálogo de saberes e práticas com estudantes do ensino médio sobre a temática “sustentabilidade e desenvolvimento local”. O trabalho foi realizado com alunos de escola pública (Escola Estadual Professora Eufrosina Pinto) no ano de 2013 por acadêmicos do curso de Tecnologia em Agroecologia da Universidade Estadual de Mato Grosso do Sul (UEMS)/Unidade Universitária de Glória de Dourados. As metodologias utilizadas foram baseadas nas concepções pedagógicas piagetianas (Jean Piaget) norteadas pelo construtivismo e fundamentos teóricos, e freirianas (Paulo Freire), aprimorados a partir da educação popular emancipadora. Os relatos foram anotados m um caderno, seguido da observação participante. A maioria dos alunos tem conhecimento e percepção significativa sobre as temas de Agroecologia, sustentabilidade e desenvolvimento local. A utilização das ferramentas pedagógicas Freirianas e Piagetianas foram de suma importância na articulação entre os eixos abordados, sendo metodologias participativas de alta relevância no processo de intervenção. Construction and rescue of knowledge about agroecology through intervention methodologies in the educational process Abstract: In pursuit of sustainable development, Agroecology is a science to articulate all the resources in the environment. But many are still unaware of the same, which is extremely important dissemination through pedagogical concepts. Thus, the aim of this study was to articulate the dialogue of knowledge and practices with high school students on the theme "sustainability and local development." The work was carried out with public school students (State School Professor Eufrosina Pinto) by students of the course of Technology in Agroecology at the State University of Mato Grosso do Sul (UEMS) / University Unit of Glória de Dourados. The methodologies used were based on Piaget pedagogical concepts (Jean Piaget) guided by constructivism and theoretical foundations, and Freirian (Paulo Freire), improved from the popular emancipatory education. The reports were noted, followed by participant observation. Most students have knowledge and significant insight into the issues of Agroecology, sustainability and local development. The use of teaching tools Freirian and Piaget were of paramount importance in linking the topics axle, participatory methodologies of high relevance in the intervention process.