Search

To guarantee seeds with high physiological quality performing in a uniform, resilient and tolerant to abiotic stress plant stand, procedures that can improve the potential of the processed seed. Biostimulants are considered promising alternatives, both to improve the physiological performance of plants and in resilience and stress tolerance. The objective of this study was to verify the effect of coating seeds of different cultivars of carrots with biostimulant based on algae Solieria filiformis on seed germination and seedling development under thermal stress. The experiment was conducted in a completely randomized design, with a 3 x 4 factorial scheme (temperatures and doses), with five replications. Carrot seeds from the cultivars Brasília, Danvers, Esplanada and Planalto were used, and the seeds were coated with doses of 0, 2, 4 and 8 mL.L-1 of biostimulant. After covering, the seeds were submitted to the following: percentage and speed of germination, length of seedlings and dry mass of seedlings. The results obtained were found in the analysis of variation and in the analysis of regression (doses) and Tukey's test (moderate). The analysis and interpretation of the results obtained in the present study allowed to conclude the high thermal stress, for all varieties, at a temperature of 35 ° C, to reduce the reduction of the analyzed variables. Furthermore, the covering of carrot seeds with the biostimulant of Solieria filiformis, in general, does not promote improvements in seed germination and in the development of carrot seedlings under thermal stress (35 °C); however, we present beneficial results for the variables analyzed at 20 and 30 ° C. [ABSTRACT FROM AUTHOR]

The initial development of corn fertilized by different fertilization sources is evaluated and the soil's rates of total organic carbon (TOC) are quantified. Assay was performed in pots, with seven treatments and five replications. Treatments comprised mineral fertilizer (AM), organic-mineral fertilizer (AO), bovine manure (EB), chicken manure (CF), sewage sludge (LE), compost barn (CB) and no fertilizer (SA). Evaluations comprised height of plant, basal diameter of stem, number of leaves at 15, 30, 45 and 60 days after seeding (DAS), length of root, volume of root, aerial dry mass and root, and calculation of dry mass (MS) per hectare at 60 DAS. Soil's TOC was calculated after assay. Treatment with AM had higher rates for plant height and stem diameter at 30 DAS. However, at 60 DAS, plants with AO and EB had a greater height and greater stem diameter, respectively. Treatments AM, EB and CF had MS above 3000 kg ha-1, whilst LE and SA showed the plants lower performance rate. Soil with CF had a higher TOC rate, 13.00 g kg-1, and SA soil and soil with AM he lowest levels of TOC. CF and EB demonstrated similar results to AM for most of the morphobiometric attributes evaluated and thus contributed towards an increase in the soil's TOC. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Agricultura Irrigada - RBAI is the property of Revista Brasileira de Agricultura Irrigada - RBAI and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of tolerant rootstocks has shown good results in the control of Fusarium wilt in yellow passion fruit, which is considered one of the main problems in the crop as it affects the plant’s root system and has no chemical control. The present study aimed to evaluate the survival rates, the agronomic performance of the plants and the physical characteristics of the yellow passion fruit (Passiflora edulis Sims) grafted on different rootstocks in area with Fusarium wilt. The experiment was carried in Pracinha, in the State of São Paulo, Brazil, from August 2014 to May 2015, and a randomized block design was adopted, with five treatments, five replications and four plants per plot. The treatments were constituted by the following rootstocks: Passiflora alata Dryand, Passiflora gibertii N.E. Brown, Passiflora caerulea Linnaeus, double grafting P. gibertii x P. edulis and plants without grafting. The stem diameter of rootstock and the graft, the lenght of secondary branches, the number of tertiary branches, the number of surviving plants, the longitudinal and transversal diameters of the fruits, the number and mass of fruits and the productivity were evaluated. The largest diameter of the rootstock was observed in Passiflora alata while in the graft it was in plants of Passiflora edulis. The length of the secondarty branches and the number of tertiary branches were affected by the type of grafting and the rootstock used. The highest survival rates were observed in Passiflora alata (90%) and Passiflora gibertii (100%). The highest number of fruits per plant and productivity occurred in plants grafted on Passiflora gibertii. The adoption of double grafting using Passiflora gibertii x Passiflora edulis and simple grafting with Passiflora caerulea were not effective in the control of this disease. The species Passiflora gibertii and Passiflora alata showed the potential to be used as a rootstock for yellow passion fruit. [ABSTRACT FROM AUTHOR]

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Producao Online is the property of Associacao Brasileira de Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective was to evaluate the nutritional content and accumulation of the rhizome and root of Strelitzia augusta plants, in nutrient solution, under macronutrient deficiency. The experiment was carried out in a greenhouse at DCS / UFLA, Lavras - MG. The statistical scheme used was the DIC with three replications, containing seven treatments, in nutrient solution. The treatments were: complete nutrient solution (control) and nutrient solutions with individual omissions of N, P, K, Ca, Mg and S. After germination, the seedlings were transferred to the complete nutrient solution with 10% of its ionic strength (adaptation period), which remained with constant aeration. The plants were selected for size uniformity and transferred to plastic pots (5L) with 100% nutrient solution, in which the treatments were applied. The plants were harvested after 180 days, after which the dry matter was collected and chemical analysis of the rhizome and roots of the plants was performed. The omission of macronutrients affects the production of dry matter from the rhizome and roots of the plant, as well as promoting changes in the contents and accumulations of nutrients. Deficiencies of macronutrients cause changes in the contents and accumulations in the rhizome and roots of this species, affecting the performance of the plant. [ABSTRACT FROM AUTHOR]

The banana tree is a tropical fruit plant, grown commercially throughout Brazil. It's commonly found of coastal regions, the banana production has been gaining space in the Paulista Plateau, mainly in the midwest region of the state. The objective of this work was to evaluate the performance of banana genotypes cultivated under microaspersion irrigation and rainfed in the edaphoclimatic conditions of Vera Cruz municipality in São Paulo state. The planting was carried out in December 2015, with micropropagated and acclimated seedlings. The statistical design adopted was randomized blocks, with 6 treatments, in a 3 x 2 factorial arrangement with 3 genotypes and 2 cultivation environments (irrigated and non irrigated). The genotypes evaluated were: BRS Princesa (Maçã subgroup), Galil 18 (Prata subgroup) and Grande Naine (Cavendish subgroup). Vegetative variables (plant height, pseudostem circumference and the number of live leaves in flowering); production variables (clusters and weight mass, productivity, number of hands per bunches and number of fruit for hand) and fruit quality (diameter, shell thickness and length), were evaluated. It is concluded that the localized irrigation by microaspersion positively interfered in the plant performance, improving the vegetative and productive characteristics of the BRS Princesa (Maçã subgroup), Galil 18 (Prata subgroup) and Grande Naine (Cavendish subgroup) genotypes, in Vera Cruz, midwest region of São Paulo state. [ABSTRACT FROM AUTHOR]

Copyright of Engenharia na Agricultura is the property of Engenharia na Agricultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The increased demand for high quality oilseeds, such as sunflower, has encouraged interest in faster tests to distinguish seed lots, and allow prompt decisions during different stages of seed production, storage, and marketing. The objective of this study was to evaluate the efficiency of the Pettenkofer method for determining respiratory activity, which can be used to differentiate the vigor of different cv. MG2 sunflower seed lots. Besides determining respiratory activity, the germination, electrical conductivity, total dry weight, fresh weight and seedling length were measured. The results permitted the classification of seed lots according to their potential performance. The Pettenkofer apparatus provided an efficient and fast separation of seed lots and the measurement of respiratory activity is promising for identifying differences in the physiological quality of sunflower seeds. [ABSTRACT FROM AUTHOR]

The effects of seed vigor on seedling emergence and stand establishment, especially under less favorable environmental conditions, are well documented in the literature. However, additional research is needed to clarify the relationships between seed physiological quality and field plant performance, and this was the main objective of this study. Two pea cultivars, 'Telefone Alta' (indeterminate growth habit) and 'Itapuã' (determinate growth habit) were evaluated, each represented by four seed lots of different physiological potential, stored for eight months under three environmental conditions: uncontrolled laboratory, a dry and cold chamber at 10 °C and 30% relative humidity, and a controlled environment (20 °C and 70% relative humidity); this procedure was adopted to promote natural differences in vigor among the seed lots. After determining germination and vigor (electrical conductivity, accelerated aging, seedling emergence and growth), a field trial was conducted to evaluate stand establishment, plant development and yield. Results showed that pea seed vigor influenced seedling emergence and stand establishment, especially for lower vigor seed lots. In addition, pea seed vigor adversely affected plant development and yield as a consequence of stand reduction. The extent of these effects was proportional to the intensity of the stand reduction. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effects of using maize seed lots constitued of high and low vigor seeds, as well as mixtures of different proportions, on plant growth and yield. Plants from high vigor seeds showed higher initial growth than those from low vigor seeds, independently of seed distribution and position in the seeding row. Comparing the yield components between plants arising from high and low vigor seeds, when the percentages of one type of seed were 100% (homogeneous lots), results were similar, but plants from low vigor seeds had inferior results on other seed distributions (heterogeneous lots). Seed vigor is directly related to initial plant growth in maize but the effects do not continue until harvest when using seed lots with homogeneous vigor. However, the use of seed lots with heterogeneous vigor results in more intra-specific competition and a lower competitive capacity for plants originating from low vigor seeds, resulting in dominated plants which grow and yield less. [ABSTRACT FROM AUTHOR]

Seed vigour may influence the establishment and growth of plants. However, the effect on plants production mostly annual crop, which harvesting is done in the reproductive phase, is not clear. The aim of this research was to evaluate the influence of sunflower achenes physiological quality on the seedlings establishment and plant performance. An experiment was installed in the field, with three lots of sunflower achenes, cultivar 'Embrapa 122 V2000', with distinct vigorous levels. Plant population was evaluated at 10, 20, 40, 60, 80 and 100 days after sowing (DAS). Plant height, leaf number, stem diameter and dry matter production were evaluated at 20, 40, 60, 80 and 100DAS. At harvest (100DAS) the number of achenes per plant, mass of 1000 achenes and achenes yield (g plant-1and kg ha-1) were also evaluated. Two and six months after harvest, the achenes were submitted to the following tests: germination, first count, accelerated aging, seedling emergence in sand, length of seedlings and electrical conductivity. The results indicated that achenes vigour affected plant population at 60DAS. Vigorous sunflower achenes improved the development of plants beyond 60DAS and this effect may persist until the final production, at initial population absence. [ABSTRACT FROM AUTHOR]