Resumo em Inglês:

ABSTRACT The objective of this work was to monitor coffee plants (Coffea arabica L.) after pruning through multispectral images obtained with an unmanned aerial vehicle (UAV) containing a Mapir Survey 3 camera and estimate agronomic parameters based on simple regression parametric models. Growth evaluation was performed in 228 sampling points related to the coffee plants. The parameters analyzed were plant height, crown diameter, plagiotropic branch length, and the number of plagiotropic branches after the pruning point. The creation of mosaics was performed through the software Agisoft PhotoScan Professional 1.4.5, and radiometric calibration through Mapir Camera Control, georeferenced by QGIS and normalized by ENVI. Based on the models generated, data analysis permitted estimating coffee plants’ agronomic parameters after decote-type pruning (cutting off the orthotropic branch at 1.5 m and 2.0 m above ground) with high accuracy. Height was measured in April’s flight with the near-infrared band (Precision = 91.87%), crown diameter and plagiotropic branches length in April’s flight with the infrared band (Precision = 89.36% and 82.22%, respectively), number of nodes in February’s flight with the near-infrared band (Precision = 79.48%), and the number of plagiotropic branches after the pruning point in June’s flight with the near-infrared band (Precision = 69.57%).

Resumo em Inglês:

ABSTRACT The knowledge of critical limits of water potential in the substrate (Ψ) allows performing irrigations that do not exceed the capacity of water storage and do not harm crop yield. In this study, substrate water retention curve was determined by inverse modeling and originated two ranges of Ψ used for irrigation scheduling: range 1, upper critical (UPΨ) = -6 kPa and lower critical (LCΨ) = -40 kPa; and range 2, UPΨ = -14 kPa and LCΨ = -40 KPa. These limits were applied in the irrigation scheduling of grape tomato in a fixed form and by changing Ψ according to the crop development stage (DS). The water productivity (WP) was determined as a function of variations in the values and form of application of Ψ. The experiment was carried out in a greenhouse. Plants were cultivated in pots filled with substrate, fertigated by an automated drip irrigation system. Tomato evapotranspiration was determined using a weighing lysimeter. Soil water content was monitored by GS1 and TDR100 sensors. Yield was not significantly affected by the different ranges of Ψ applied. WP was statistically higher in plants subjected to range 2 throughout the crop cycle and in at least one of the DS.

Resumo em Inglês:

ABSTRACT This study evaluated the variability of photosynthetic performance of 27 improved genotypes of Conilon coffee, cultivated in the Southern of the Espírito Santo State. The photosynthetic performance was based on the measurement of gas exchange rates and chlorophyll in the period most favorable to the photosynthetic activity and in different stages of the reproductive cycle: flowering, fruit initiation, grain formation and fruit maturation; being expressed as the average (weighted by the number of days) along the phenological stages of the third reproductive cycle of the plants. It was possible to verify the existence of sufficient variability to differentiate the photosynthetic performance among the 27 genotypes throughout the reproductive cycle, even starting from a group of already improved genotypes. Among the physiological parameters, the rate of carbon assimilation, stomatal conductance and the transpiration rate stood out as parameters for the study of variability, mainly due to their contributions to the clustering of genotypes. The genotype 108 is highlighted due to its high photosynthetic rate, associated with higher relative content of chlorophyll, as well as reasonable water use efficiency. The genotypes 205, 206 and 305 stood out in terms of water use and carbon assimilation.

Resumo em Inglês:

ABSTRACT In pest control, understanding insecticide compatibility and selectivity is crucial to effectively integrate the use of insecticides and parasitoids. The aim of this study was to evaluate the compatibility of mixtures of insecticides and fungicides recommended for melon and their selectivity in Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). The were evaluated the compatibility of six mixtures: 1) Spinetoram + Pyraclostrobin and Fluxapyroxad; 2) Cyromazine + Pyraclostrobin and Fluxapyroxad; 3) Cyproconazole + Spinetoram; 4) Cyantraniliprole + Abamectin + Metiram and Pyraclostrobin; 5) Spinetoram + Azoxystrobin and Difenoconazole; 6) Abamectin + Cyantraniliprole; and a Control (distilled water). The compatible mixtures were applied to Anagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) eggs, before and after T. pretiosum parasitism. Was evaluated: mortality of adult T. pretiosum females after exposure to treated eggs, parasitism, emergence and number of parasitoids emerged/egg. Only treatment 4 showed change in physical stability after 5 minutes. In selectivity tests, treatments 1, 3, and 5 caused greater mortality (>47%) of female adults. In pre-parasitism, parasitism (>77%) and emergence (>76%) were observed in all treatments, and all the mixtures were classified as innocuous to the parasitoid in these parameters. In post-parasitism, treatments affected negatively emergence (>51%) and number of parasitoids/egg at the three ages studied. Therefore, all mixtures were considered stable and viable for use with T. pretiosum, as long as they were applied before parasitoid releases.

Resumo em Inglês:

ABSTRACT Terbuthylazine, as well as atrazine, is a triazine with the mechanism of action of photosystem II (PSII) inhibitors, effective in controlling weeds in maize crops. The aim of this study was to assess the efficacy of terbuthylazine, atrazine, and atrazine + mesotrione, alone or in mixtures with glyphosate, in weed control for post-emergence application in maize. The experiment was conducted over two growing seasons, evaluating weed control, damage symptoms in maize and maize yield. No damage symptoms were observed in maize, and when differences in yield were observed, they were due to differences in treatment efficacy in weed control. The efficacy of terbuthylazine is akin to that of atrazine in controlling broadleaf weeds (until 93.8%) and tends to be superior in controlling grasses (until 87.5% for terbuthylazine, until 76.3% for atrazine) or Commelina benghalensis (until 91.3% for terbuthylazine, until 82.5% for atrazine). Terbuthylazine or atrazine + mesotrione, alone or in a mixture with glyphosate, were effective in post-emergence weed control in maize, with a broad spectrum of action. Atrazine, alone or in a mixture with glyphosate, was effective in controlling broadleaf weeds (Richardia brasiliensis, Bidens subalternans, and volunteer soybeans).

Resumo em Inglês:

ABSTRACT Soil conditioners have humic acid levels which can control nematodes and promote plant nutrition. The objective of this work was to evaluate different concentrations and doses of commercial soil conditioner Premium® on motility, mortality, hatching, infectivity and reproduction of Meloidogyne incognita in tomato. In order to evaluate motility, mortality, and hatching, second stage juveniles (J2) or eggs were subjected to incubation at different concentrations of soil conditioner. To evaluate infectivity and reproduction, infested soil with M. incognita were mixed to different concentrations of commercial soil conditioner. Thirty-day-old tomato seedlings (cv. Kada) were transplanted into the pots and after 30 days the numbers of galls, egg masses and eggs per gram of root were evaluated. The use of soil conditioner drastically reduced motility at a concentration of 66.67 g L-1 and caused mortality above 98% in M. incognita J2 at 133.33 g L-1. Exposure of eggs to soil conditioner reduced J2 hatching by more than 50% at a concentration of 2.5 g L-1. Highest concentrations of soil conditioner provided lower infectivity and reproduction of M. incognita in tomato. Soil conditioner at a dose of 5.0 g provided greater development of the root system, demonstrating the efficiency of this product.

Resumo em Inglês:

ABSTRACT Phoma leaf spot (Phoma spp.) of coffee causes losses of between 15 and 43%, and presents significant variability over time and space, especially in mountain coffee production. Thus, the objective of this study was to evaluate the behavior of this disease at different altitudes and to use time series techniques and regression models to explain disease behavior. The experiment was conducted over two years (from September 2013 to August 2015) with monthly evaluations in a Coffea arabica L. plantation. The incidence and severity progress curves showed irregular behavior most of the time, typical of the disease. Higher altitudes provided higher disease incidence and severity values. Only the incidence and severity progress curves at the altitude of 1143.2 m showed significant autocorrelation over time. Thus, the first-order autocorrelation structure, AR(1), was incorporated in the estimates of the parameters of the linear and nonlinear models. Only the months from February to June/July 2014 were considered, when the disease progressed regularly. The rates obtained for the incidence, overall mean of the 85 points and mean altitude of 1143.2 m, were 5.2 and 4.6%, respectively, while the estimated rates for the severity data under the same conditions were 0.3 and 0.1%, respectively. These values represent the expected increase in incidence and severity each month. The Phoma leaf spot presents complex temporal dynamics, influenced by microclimatic variables associated with altitude.

Resumo em Inglês:

ABSTRACT Commelina benghalensis has become one of the main weeds in the second-crop soybean‒corn system, and the use of auxinic herbicides is essential for its control. The objective of this study was to evaluate the control efficacy of treatments applied in off-season management before soybean cultivation using the herbicides florpyrauxifen-benzyl and other synthetic auxins in the control of C. benghalensis. Experiment 1 consisted of the application of florpyrauxifen-benzyl + glyphosate, triclopyr + glyphosate, [halauxifen + diclosulam] + glyphosate, [halauxifen + diclosulam] + glufosinate, [halauxifen + diclosulam] + glyphosate + saflufenacil, and [halauxifen + diclosulam] + glyphosate + carfentrazone; Experiment 2 consisted of the application of florpyrauxifen-benzyl + glyphosate, triclopyr + glyphosate, halauxifen + glyphosate, [halauxifen + diclosulam] + glyphosate, [halauxifen + diclosulam] + glyphosate + glufosinate, and [halauxifen + diclosulam] + glyphosate + carfentrazone. At 60 days after application, florpyrauxifen-benzyl + glyphosate reached 73.8% efficacy in the control of C. benghalensis in Experiment 1 and 92% in Experiment 2, whereas the other treatments presented a maximum control of 55.5%. The application of florpyrauxifen-benzyl + glyphosate effectively controlled C. benghalensis when applied during off-season management before soybean sowing. Florpyrauxifen-benzyl was superior in efficacy to treatments involving the application of other synthetic auxins.

Resumo em Inglês:

ABSTRACT Quizalofop-p-ethyl is used in ProvisiaTM rice for selecive grass weed control. In southern Brazil, other weeds occur, and an herbicide tank mix is needed to achieve a broad spectrum. This study aimed to evaluate the interaction of quizalofop-p-ethyl with other herbicides used to control the main paddy rice weeds occurring in Southern Brazil. Two greenhouse experiments were performed using Aeschynomene denticulata Rudd (jointvetches), Cyperus iria L. (rice flatsedge), Echinochloa crus-galli L. (barnyard grass), and Oryza spp. (weedy rice). The factorial arrangement to each species comprises: Factor A) Doses of quizalo-fop-p-ethyl (g ha-1): 0, 120, and 120 plus 120 (applied 14 days after the initial treatment - DAIT); Factor B) Tank mix partner: bentazon (960 g ha-1), florpyrauxifen-benzyl (30 g ha-1), quinclorac (375 g ha-1), saflufenacil (30 g ha-1), and control. At 42 DAIT, control and shoot dry weight (SDW) were evaluated. Colby’s method compared treatments using Tukey’s HSD and tank mix. No herbicide tank mix reduced or increased the variables evaluated compared to the herbicides applied alone, suggesting a neutral effect. Between the mixtures, in terms of spectrum of weed control, quizalofop-p-ethyl plus florpyrauxifen-benzyl was the best treatment, providing effective control or SDW reduction (≥ 90%) in all tested species.

Resumo em Inglês:

ABSTRACT The aim of the work was to employ general and specific combinatorial capacity to select possible genetic bases and parents that meet the agronomic ideotype of soybean precocity and grain yield. The experiment was conducted at the Regional University of the State of Rio Grande do Sul. The experimental design used was that of augmented blocks, with interspersed controls, with treatments distributed in four blocks allocated throughout the experiment. To reduce pod insertion height, specific breeding strategies are suggested. For the ideal plant height, line 195 is selected. Lines 262 and 286 are chosen for their early maturity traits, while lines 893 and 661 are selected to improve grain weight per plant. These selections aim to enhance plant growth and yield. The general and specific combining capacity allows the selection of additive and complementary gene constitutions for insertion height of the first pods with the parents Massal Maradona RR 15b70 IPRO, plant height with HO Puricá x HO Jacuí IPRO, precocity through TMG 7262 RR x 15b70 IPRO, grain yield attributes through NS 6700 IPRO x BMX Valente 6968 RSF and DM 7.0 BMX Magna x BMX Ativa RR.

Resumo em Inglês:

ABSTRACT The aim of this work was to evaluate the potential use of the peel of pitaya fruits for jam production. Four pitaya jelly formulations with different peel proportions used in place of the pulp (0, 20, 40 and 60%) were evaluated. The inclusion of peel in the formulation of red pitaya jelly is viable, and the product quality is maintained, especially at a 20% peel proportion, which is better accepted by tasters than are higher proportions. The 20% substitution of pulp with peel resulted in higher mean consistency and overall impression values than the other formulations. The levels of soluble solids and titratable acidity and the soluble solids/titratable acidity ratio did not significantly differ among the products, with mean values of 64.6%, 1.05%, and 61.67% with 20%, 40% and 60% peel addition, respectively. Substituting pulp with pitaya mesocarp resulted in an increase in jelly pH. The adhesiveness and cohesiveness of the jellies increased as the percentage of peel increased. The microbiological results of this study indicate the absence of microorganisms in the jellies. Thus, the use of peel in jam production can minimize production losses while adding value to the product and reducing waste disposal in the environment.

Resumo em Inglês:

ABSTRACT Rust caused by Cerotelium fici leads to significant defoliation in common fig trees (Ficus carica). However, studies on its epidemiology remain scarce. The aim of the present study is to investigate common fig rust progress in leaves inoculated at different ages over two growing seasons (dry and rainy) in an experimental fig orchard. Artificially inoculated leaves and those exposed to natural infection showed more severe rust symptoms when they were inoculated earlier - up to 45 days after leaf emergence. Disease severity and leaf longevity (in days) were inversely and directly proportional to leaf age at inoculation time, respectively. Leaves inoculated at earlier presented significantly higher disease progression rates based on number of pustules per cm², broader area under the disease progress curve (AUDPC) recorded for pustule density and higher maximum severity, which was visually estimated as the percentage of lesioned leaf area. Inoculated young leaves abscised 40 to 60 days earlier than the uninoculated leaves, which were protected from natural infection by plastic bags. The uninoculated leaves remained attached to the plants from 90 to 100 days. These findings highlight apical sprouts as primary targets for protective fungicide applications, which must be more intense at early growing season in order control rust in common fig crops.

Resumo em Inglês:

ABSTRACT Citrus orchards have been planted in higher tree densities, which encourage the use of rootstocks that reduce scion tree size. The performance of low-vigor rootstocks with ‘Valência’ orange is not well known, especially in southern Brazil. The objective of this work is to compare the agronomic performance of ‘Valência’ sweet orange grafted on seventeen rootstocks in western Santa Catarina, Brazil, and analyze the results in light of the search for small trees for orchards with narrower spacing. An experiment was conducted over 10 years for evaluation of seventeen rootstocks, concerning tree size, yield and fruit quality. The rootstocks were classified in Standard (six genotypes, including ‘Swingle’, main rootstock in Santa Catarina), Super-standard (two genotypes), Semi-standard (seven genotypes) and Dwarf (two genotypes). An estimated hectare yield was calculated after a tree spacing adjustment based on tree diameter. In conclusion, the citrandarin ‘San Diego’ forms trees similar in size to the widespread citrumelo ‘Swingle’, but is more productive, and maintains the quality of the fruit. ‘Fepagro C37 Dornelles’ reduces ‘Valência’ tree size, facilitates fruit harvest and induces it to produce big, good quality fruits. Dwarf rootstocks lead to a low hectare yield even in reduced space orchards.

Resumo em Inglês:

ABSTRACT Soybean cultivation holds national and international significance, necessitating sustainable production practices. This study evaluated the impact of plant growth-promoting rhizobacteria (PGPR) and cover crops on soybean yield components and grain yield. The experiment followed a randomized block design in a 5 × 2 factorial scheme with four replications. Treatments included the application of a PGPR combination (Bacillus sp. + Serratia marcescens) and five cover crops grown in the off-season: rice, corn, millet, Urochloa ruziziensis, and a cover crops mix. Over five agricultural seasons (2019/20–2023/24), we assessed the number of pods per plant, grains per pod, 100-grain mass, and grain yield. Cover crops did not influence yield components or grain yield. However, applying the PGPR mixture (Bacillus sp. BRM 63573 + Serratia marcescens BRM 32114) significantly improved 100-grain mass and grain yield. Among climatic factors, solar radiation was the primary determinant of grain yield variation. These findings highlight the potential of PGPR to enhance soybean production sustainably, while cover crops may require further investigation to optimize their role in this system.

Resumo em Inglês:

ABSTRACT Potassium (K) fertilization strategies are crucial for maximizing cotton yield and fiber quality in Brazil’s Cerrado region. This study evaluated the effects of K source and application timing on cotton performance in Western Bahia. The experiment followed a randomized block design with four replications. Treatments included pre-planting applications of muriate of potash (MOP), polyhalite (Poly4), and a 50/50 MOP/Poly4 blend; post-planting (topdressing) applications of MOP and Poly4; and a control without K. Seed yield, fiber yield, fiber quality parameters, and macronutrient concentrations were assessed. Potassium fertilization significantly increased seed and fiber yields compared to the control. Among the fertilized treatments, yields and fiber quality were statistically similar. The highest leaf K concentration was observed in the post-planting Poly4 treatment, while both this treatment and the control had the highest Mg concentrations. Sulfur concentrations were higher in all fertilized treatments than in the control. Fiber quality did not differ significantly among treatments, except for the yellowing grade (+b), which was lower in the control. Additionally, cotton classification grades were higher in all fertilized treatments. These results indicate that Poly4 is a viable alternative to MOP for cotton cultivation in Western Bahia, offering additional macronutrients and flexibility in application timing.

Resumo em Inglês:

ABSTRACT This study aimed to evaluate the yield of essential oil extracted from different sample and pH compositions, as well as the insecticidal potential of Pinus taeda essential oil. For this, samples composed only of needle and composed of needle and branches were kept in solvent water at different pH (3, 4, 5 and 6). Subsequently, the oils extracted in the different pH treatments were added in a proportion of 25% to Tween® (20%) and sunflower oil (55%) forming a concentrated bioinsecticide solutions at each pH. Solutions were diluted in deionized water to final concentrations of 12.5, 6.2, 3.1 and 0% oil. The samples containing needles and branches, as well as those extracted at pH between 4 and 6, provided a higher yield of essential oil. The bioinsecticide formulations containing the highest concentrations of essential oil extracted at pH 3 showed the best results in the control of S. zeamais. The essential oil of P. taeda has potential for the preparation of bioinsecticides and can be extracted from samples containing needles and twigs in a solvent with pH 3. Bioinsecticide solutions of higher concentrations are more efficient in controlling S. zeamais after 24 hours of exposure.

Resumo em Inglês:

ABSTRACT Corn intercropped with Urochloa contributes not only to increasing soil coverage but also to improving physical, biological, and chemical quality, especially in Cerrado soils that have low phosphorus availability. Therefore, the objective of this work was to evaluate the response of different doses of phosphorus (P) in production systems on the chemical attributes of the soil, and physiological, biometric, and productive parameters of corn. Thus, an experiment was conducted with a randomized block design in a split-plot scheme, with four replications. The plots consisted of two production systems: single corn and intercropped corn. The subplots consisted of three doses of phosphorus. Soil chemical attributes, gas exchange, chlorophyll content, biometric components, and corn productivity were evaluated. The physiological parameters were not affected by the systems and P doses. In the biometric components, there was a significant effect only for stalk diameter, where corn in the single system had a larger diameter in comparison to the intercropped one. There were effects for P contents in the system and dose factors, while for organic matter and carbon only in the dose factor. Production systems and phosphate fertilizer did not influence corn grain productivity.

Resumo em Inglês:

ABSTRACT Macronutrients are essential for plants, and their deficiency results in decreased productivity, hindering the plant from completing its life cycle. The aim of this study was to evaluate the effect and symptomatology of macronutrient omission in maize (Zea mays L.) cultivation. The experiment was conducted in a greenhouse, with the following treatments: T1: no macronutrients; T2: complete except for Nitrogen; T3: complete except for Phosphorus; T4: complete except for Potassium; T5: complete except for Calcium; T6: complete except for Magnesium; T7: complete except for Sulfur; and T8: all nutrients included. Micronutrients were added to the treatments, irrigated with 60% water retention capacity. A Completely Randomized Design was applied, with 5 repetitions per treatment. After 80 days, the analyzed variables were: plant height, number of leaves, stem diameter, fresh mass weight, and dry mass of above-ground and root parts. Analysis of variance was performed, and means were compared using the T-test for multiple comparisons (LSD) at a 5% probability level. Treatments with omission of N, P, and S were the most affected in all evaluated variables. On the other hand, the absence of Ca, K, and Mg nutrients had little impact on plant development.