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Low rainfall rates are becoming increasingly frequent because of climate change, causing droughts and threatening world food security. For popcorn, drought is the most limiting abiotic factor for plant's growth and development. Thus, the water deficit directly impacts for crop productivity. Based on knowledge of the genetic basis of traits involved in stages of popcorn germination and seedling development under water stress, genotypes with potential for adaptation to adverse growing conditions can be selected early. Therefore, data on genetic effects and combining ability of 10 popcorn parents were compiled to propose breeding strategies for the development of cultivars with greater adaptation to water stress in the early stages. Forty-five diallel hybrids were evaluated under two different water regimes, that is, water stress and full irrigation. This corresponded to a water retention capacity of 25% and 70% of the germination paper. The plants were watered daily as needed for seven days. A range of factors were evaluated, that is, germination traits including the germination speed index and germination on the seventh day; shoot traits including length and dry weight; and root system including length, dry weight, root-to-shoot ratio, maximum root number, root network area, specific and root network length, and root volume. Breeding for drought adaption in the early stages of popcorn development can be successful when hybrids are used, because of the genetic effects of dominance (Φs). These control the traits evaluated at the seedling stage. The combinations L61 x P2 and L71 x P3 were recommended, in view of the more successful performance estimated for traits related to the shoot and root system. [ABSTRACT FROM AUTHOR]

This study was developed to carry out selection, estimate genetic parameters and predict individual genetic values of 55 genotypes from S2 families as well as estimate genetic dissimilarity based on physiological seed attributes. All S2 genotypes evaluated were obtained from self-pollination of S1 genotypes from the guava breeding program. The experiment was laid out in blocks with 55 S2 genotypes and four blocks. Genetic parameters were estimated and the best genotypes were selected based on the genetic value, using the statistical method of mixed models. In addition, genetic divergence was estimated based on the mean Euclidean distance. Although heritability values were considered medium to high magnitude for germination (0.22) and germination speed index (0.35), genetic gains were obtained for all traits. Based on the evaluation of individual BLUPs, the S2 genotypes that contributed to most of the evaluated traits were: 5, 31, 85, 214, 369, 393, 398, 442, 443, 444, 449 and 529, suggesting potential to generate vigorous. Through genetic dissimilarity, it was possible to verify the formation of five distinct groups. Therefore, the selection of divergent genotypes with high average for germination is recommended for the advancement of generation in the guava breeding plant. [ABSTRACT FROM AUTHOR]

Copyright of Ciência Florestal (01039954) is the property of Ciencia Florestal 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.)

Sorghum (Sorghum bicolor) is highly sensitive to zinc deficiency in soils, which results in decreased productivity and low-quality agricultural products. Our objective was to evaluate the effects of different zinc doses, applied to seeds, on the physiological quality and initial performance of sorghum plants. Six doses (0, 3.5, 7.0, 14.0, 21.0, and 28.0 g kg-1 seeds) were used and an uncoated control. The Zn coating process used dolomitic limestone as the filler and glue. Laboratory tests were conducted in a completely randomized design and greenhouse experiments were conducted in a randomized block design. The control means were 8, 9, and 14% lower than the maximum, minimum, and total seed area of treatments, respectively, relative to that of treatments. The control differed from other treatments by 10.47 in the speed index of emergence. Zinc at a dose of 28 g kg-1 seeds provided greater production of aerial dry matter, with nutrient content of 75.85 mg kg-1. Zinc on sorghum seeds affected length and dry matter production of aerial parts and roots but did not affect physical characteristics, germination, or emergence time. Applied zinc accumulated mainly in the roots, and promotes changes in Ca and Mg in seeds and other plant parts. [ABSTRACT FROM AUTHOR]

The seed coating technique adds value to the seeds. This technique allows changing the seed size and shape, facilitating sowing, and also the application of essential nutrients to the good development of the plant in the postgermination phases. Therefore, the objective of this work was to evaluate the physical and physiological characteristics of Stylosanthes capitata/macrocephala coated with different materials. For the coating procedure, a N10 Newpack bench seed coating machine was used. The experimental design was completely randomized, with four replications and 50 seeds per plot distributed in 10 treatments. The different materials and their respective mixtures significantly altered the physical characteristics, the weight of a thousand seeds (WTS), water content (SWC), maximum diameter (DMA), and minimum diameter (DMI) of the seeds. Among the different materials, the sand coated seeds had the highest germination percentage (%G), germination velocity index (GSI), and first germination count (FGC). The maintenance of physiological attributes was observed in sand coated seeds (0.25 mm). Therefore, it is an alternative application of nutrients via seeds, due to the inert character of the sand. The mixing of the materials used in this work is not recommended. [ABSTRACT FROM AUTHOR]

The processing yield or performance, which includes drying and depulping of coffee fruits, can be calculated as the relationship between the volume of ripe coffee fruits and green coffee weight and is a relevant characteristic for the development of new cultivars. The purpose of this study was to evaluate the processing performance of 42 genotypes and one population of Coffea canephora. The treatments consisted of 42 C. canephora genotypes propagated by cuttings and one seed-derived population arranged in a randomized block design with three replications. The genotypes were harvested when 80% of the fruits were in the ripe stage (red berries). We evaluated the relationship of the volume to weight of ripe fruit (ripe fruit volume [RFV]/ripe fruit weight [RFW]), the percentage of seed per fruit (% of seeds), the yield (in liters of ripe coffee) required to produce a 60-kg bag of green coffee, and the relationship between RFW and dry green bean weight (RFW/dry seed weight [DSW]). The results were subjected to ANOVA, and the means were grouped by the Scott-Knott test (p ≤ .05). The mean yield of the evaluated genotypes was 347.57 L bag-1 of green coffee (between 294.01 and 439.72 L bag-1). A lower seed per fruit percentage identifies genotypes with a lower yield and higher RFW/DSW ratio. The genotypes Z21, 700, AD1, LB1, Emcapa 143, and AP required less than 315 L of ripe coffee to produce one 60-kg bag of green coffee beans. [ABSTRACT FROM AUTHOR]

Perennial soybean (Neonotonia wightii) is a Fabaceae with potential to be used in consortium with Poaceae plants to improve pasture quality. In order to add value to perennial soybean seeds and improve their seed distribution, seeds coated with different materials in coating machine were characterized by digital image analysis and physical attributes related to physiological attributes in order to define the ideal amount and material to be used in the coating. Different material quantities were tested, 150 g, 200 g and 250 g, divided into layers, namely: sand, calcium silicate + sand and limestone + sand. Coating promoted maximum increments of approximately 350% in seed mass and significant increases of up to 230% in area, 154% in maximum diameter, 162% in minimum diameter, 167% in contained diameter and 152% in perimeter. The coating was also efficient in reducing the moisture of the pellets by increasing the layers that cover the seeds. The sand + limestone combination resulted in the largest pellets. The combination of sand + silicate did not interfere with plant speed and formation. Thus, it was considered the appropriate material for the coating of perennial soybean seeds. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agronómica is the property of Universidad Nacional de Colombia 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.)

Jatropha seeds were classified according to tolerance to desiccation and storage, as a way to subsidize future propagation programs, as jatropha seed shows to be a promising oilseed for biodiesel production. The objective of this work was to study the physiological classification regarding the tolerance of physic nut seeds to desiccation and storage at low temperatures and to verify if their behavior was closer to that of seeds classified as orthodox, recalcitrant or intermediate. The seeds were harvested in the morning and sent to the Laboratory, being processed and submitted to drying, storage and emergency assessment. For seed quality analysis, the germination test and the emergence speed index were used, using a completely randomized design, with four treatments (no drying, 12% humidity, 5% humidity and 12% humidity a -20°C for 90 days) and five repetitions. After physiological classification, it was found that seeds of physic nut are orthodox, thus can be stored at low temperature (-20°C) and with low water content (<5%), without compromising their viability. [ABSTRACT FROM AUTHOR]

The interest in Syagrus schizophylla as an ornamental palm tree and the demand for conservation and preservation of the species led to this research. The objective was to study the physiological characteristics of its germination at different temperatures, as well as the morphological and biometrical characterization of diaspores and seedlings at the initial stages of growth and development. The research was divided into two experiments. In the first one, the aim was to identify the water absorption phases of seeds during germination under five scarification treatments as follows: intact diaspores, scarified diaspores, diaspores with endocarp rupture and intact seeds. In the second experiment, germination was tested at 25, 30 e 25 - 35 ºC; the first germination count, seedling emergence, abnormal seedlings, non-germinated seeds, the emergence curve, the emergence speed index and the mean time of emergence were evaluated. Afterwards, the morphological and biometrical characteristics of diaspores and seedlings were described. The water absorption curve observed under the different scarification treatments showed different water absorption patterns. Emergence percentages were 53, 61 and 47% at 25, 30 and 25 - 35 ºC, respectively. The highest emergence speed index was obtained at 30 ºC. The mean time of emergence was 30 days, approximately, under all the temperatures tested. The diaspores showed a great variability in both shape and size, presenting a globular to ovoid shape with an average length of 2.44 cm and an average width of 1.39 cm. The germination can be classified as hypogeal crypto cotyledonal of the remote-tubular type. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the dry matter yield of shoot and root and chemical composition of three tropical forage legumes (Clitorea ternatea, Macrotyloma axillare e Neonotonia wightii) that after having their seeds passed through the digestive tract of cattle, germinated and developed in bovine fecal plaques. The experimental design was completely randomized, in a factorial scheme 3 (species) x 3 (dispersion intervals: between 12 and 18; between 18 and 24, between 24 and 30 hours) with four replications. 50 g of mixed seeds offered to 150 g of bovine mineral supplement per replicate. The bovine dungs collected and placed in pots, where they remained for 120 days. At the end of this period, the plants in the dungs were counted and cut and analyzes were performed to determine the dry matter production of shoot and root, crude protein (CP), neutral detergent fiber (NDF) and detergent fiber acid (FDA). The plants developed in the dungs were able to express good dry matter production. The perennial soybeans presented the highest dry matter yield of aerial part (2.81 g/plant) and root (2.05 g/plant). The contents of PB, NDF and FDA did not change within the periods of dispersion in which the seeds were grown. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the physiological potential of stylosanthes seeds cv. Campo Grande in response to coating with zinc and boron. The treatments were: T1 - uncoated seeds; T2 - seeds coated with calcium silicate; T3 - 80 g of B + 60 g of Zn.kg-1 seeds; T4 - 120 g of B + 90 g of Zn.kg-1 seeds; T5 - 160 g of B + 120 g of Zn.kg-1 of seed and; T6 - 200 g of B + 150 g of Zn.kg-1 of seed. The seeds were evaluated by germination test, speed index and mean time of germination (GSI and MGT), seedlings emergence test, speed index and mean emergence time (ESI and MET), shoot and root length (SL and RL), leaf area (LA), number of nodes (NN) and shoot and root fresh (SFW and RFW) and dry weight (SDW and RDW). Coating reduced the germination and seed vigor. Micronutrients favored plants development, after its establishment. The coating with 120 g of B + 90 g de Zn.kg-1 of seed favors the growth, development and nodulation of the plants. [ABSTRACT FROM AUTHOR]

The amount of nutrients present in husks and beans from Conilon coffee fruits directly influence the crop nutritional management, as well as its use as a complement to conventional fertilization. The present study aimed to quantify the concentration and accumulation of nutrients in husks, beans and whole fruit in irrigated and non-irrigated plants from the cropped genotype C. canephora cv. Conilon Clone 02, from clonal variety EMCAPA 8111. The experiment consisted of two treatments (irrigated and non-irrigated) in a completely randomized design with 28 replicates under field conditions, in southern Bahia, Brazil. During harvesting stage, 50 fruits per plant, in two consecutive harvests, were collected to quantify the dry matter and accumulation of nutrients in the husks, beans and fruits. The fruits from irrigated coffee plants showed higher N, P, K, Ca, Mg, Cu and Mn accumulation than non-irrigated plants. The huskand beans from irrigated coffee plants showed higher Ca, Zn and Cu and N, P, Ca, Mg, S, Cu and Mn accumulation, respectively, than non-irrigated coffee. Regarding the nutrient accumulation, K followed by N, and Ca were the most represented macronutrients in coffee husk. N followed by K and P, and N followed by K and Ca were the most represented macronutrients in beans and fruit, respectively. Fe and B were the micronutrients found in higher contents in husk, beans and fruits from Conilon coffee. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effect of different coatings on the physiological potential of stylosanthes cv. Campo Grande seeds. The treatments were: uncoated seeds; limestone + PVA glue; limestone + sand + PVA glue; limestone + activated carbon + PVA glue; calcium silicate + PVA glue; calcium silicate + sand + PVA glue; calcium silicate + activated carbon + PVA glue. Posteriorly, the seeds were analyzed for water content (WC), maximum diameter (MAD) and minimum diameter (MID), thousand seed weight (TSW), germination test, germination speed index (GSI), mean germination time (MGT), emergence, emergence speed index (ESI), mean emergence time (MET), shoot and root length, fresh and dry matter of shoot and root. The coating increased the TSW, MAD and MID and decreased its WC. The treatments comprising limestone + PVA glue and limestone + sand + PVA glue increased the germination time, but none of the treatments negatively affected the physiological seed quality. Treatment with calcium silicate + PVA glue was outstanding for germination speed index and fresh and dry matter of shoot and root in the stylosanthes cv. Campo Grande seeds coating. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ceres is the property of Revista Ceres 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.)

This research studied growth and yield of Syagrus schizophylla, an extinction-endangered ornamental palm, grown under five light gradients. The treatments were: G1 - PAR=1234.10 μmol photons m-2 s-1, G2 - PAR=913.16 μmol photons m-2 s-1, G3 - PAR=666.34 μmol photons m-2 s-1, G4 - PAR=419.56 μmol photons m-2 s-1 and G5 - PAR=534.77 μmol photons m-2s-1. Before the experiment and at three, five and seven months of treatment, growth (plant height, collar diameter, number of leaves, petiole length, leaf length and width), gas exchange, chlorophyll a, and leaf green color intensity were assessed. The highest net photosynthetic rates were observed in plants under G2, G3 and G4. Values of maximum quantum efficiency (Fv/Fm) over 0.75 were observed under G2. At seven months, estimated SPAD values were 36 in G2 plants and 32 in G1 plants. According to the Dickson quality index (DQI), presented the highest growth and development rates. We conclude that G2 suits plants to be transplanted into the field, whereas G3 would be best for plants grown under shade environments. [ABSTRACT FROM AUTHOR]

Andina is a conilon coffee variety originated from a selection of clones discovered by farmers. It was cultivated and evaluated for yield and plant vigor an altitude of 850m asl. Five genotypes (A1, NV2, NV8, P1 and Verdim TA), with a mean yield of 51.3 bags per hectare per year. [ABSTRACT FROM AUTHOR]

El Sistema Integrado de Diagnóstico y Recomendación (DRIS), a pesar de ser de uso común en la interpretación de los análisis foliares, ha sido poco utilizado en el análisis químico del suelo. Las recomendaciones de correctivos y fertilizantes para la región del Cerrado, fueron desarrolladas para el sistema de cultivo convencional, bajo estudios de calibración, sin incluir los avances tecnológicos actuales. En este sentido, se propuso como objetivo establecer el diagnóstico integrado y rangos de nutrientes en suelos bajo cultivo de frijol (Phaseolus vulgaris) en esta región. Las muestras de suelo se recogieron en la profundidad de 0-20 cm, evaluando las cantidades de materia orgánica, Ca, Mg, K, P, S, Zn, Cu, Fe, Mn, saturación de bases y la capacidad de intercambio de cationes. Se logró establecer normas DRIS y rangos de suficiencia del suelo, a partir de cultivos con una productividad igual y superior a 2700 kg ha-1 de frijol común, que son aplicables en la recomendación de fertilizantes de este cultivo en la región. La mayoría de los parámetros establecidos presentan discrepancias, en relación al referencial teórico existente actualmente para la región. Los resultados mostraron que en lugar de su universalidad es importante el desarrollo de normas regionales y específicos en siembra directa para la aplicación de las normas DRIS y rangos de suficiencia en el suelo, en cultivos de alta productividad. [ABSTRACT FROM AUTHOR]