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Seeds physical and physiological qualities are primarily determined by seed physiological maturity. Seed enhancement technology has developed rapidly, including using ultrafine bubbles (UFB) and plasma-activated water (PAW) to increase seed viability. This study aimed to determine seed physiology maturity on okra seed to get the optimal harvesting period seeds and to examine the most effective seed enhancement plasma-activated water and ultrafine-bubble Water. The first experiment was arranged using completely randomized design with fruit maturity as the single factor, harvested at 3, 4, 5, or 6 weeks after anthesis (WAA), with three replications. The second experiment used factorial completely randomized design; the first factor is seed lots with different storage times (fresh seed and one-year storage seed), and the second factor seed invigoration using UFB (20 ppm dissolved oxygen) and PAW (10-, 20-, and 30-min exposure) as the second factor. Untreated seeds were used as control. Fifty seeds were used in each treatment. Okra seed physiological maturity was reached at 5 WAA based on seed dry weight, germination capacity, seedling vigor, and speed of germination. The pod color at 5 WAA is olive brown, and seed testa has dark greyish purple. Plasma-activated water at 10 minutes exposure increased the vigor index of seed lots stored for one year by 86% and PAW20 by 87%. Plasma activated water at 10-, 20- and 30-minutes exposures significantly increased the seedling vigor index and germination speed of fresh seeds harvested at 5 WAA.

Abstract The objective of this work was to evaluate the performance of okra grafted onto Hibiscus spp. in the presence and absence of three root knot nematode species. The experimental design was completely randomized in a 4x4 factorial arrangement with ten replicates. The first factor consisted of the following four rootstocks: kenaf (Hibiscus cannabinus), false roselle (Hibiscus acetosella), self-grafted, and non-grafted. The second factor was the inoculation of 5,000 eggs and second-stage juveniles of Meloidogyne incognita, Meloidogyne javanica, and Meloidogyne enterolobii in okra plants, plus an uninoculated control. Vegetative development, agronomic performance, and nematode reproduction were evaluated. The grafting of okra onto Hibiscus spp. in the presence of root-knot nematodes provided a greater plant height, scion length, fresh shoot mass, number of fruits, and yield, when compared with self-grafted and non-grafted plants. The averages of the root-knot nematode reproduction factor were low in the plants grafted onto Hibiscus spp., indicating that grafting in the presence of root-knot nematodes is capable of maintaining okra vegetative development and yield.

ABSTRACT The objective of this study was to assess seed health and the effect of plant extracts on Fusarium oxysporum f. sp. vasinfectum mycelial growth and sporulation, plant pathogen reduction in seeds and fusariosis control in okra seedlings. Health was assessed by the Blotter Test, after immersing the seeds in natural extracts and plating. To verify the mycelial growth of the plant pathogen, the extracts were incorporated in PDA culture medium and the pathogen was added and assessed, including the spore count. In the greenhouse, the seeds were immersed in the extracts, sown and at 15 days they were sprayed with extracts, at 21 days inoculated with the pathogen and disease severity on the seedlings was assessed 7 days later. There were higher incidences of Fusarium sp. and Rhizopus stolonifer in the seeds of the cultivars Valença and Santa Cruz 47. The extracts that resulted in lower pathogen incidence was basil, in cv. Valença and cinnamon and neem, in cv. Santa Cruz 47. The neem treatment presented the best inhibition percentage and the lowest sporulation mean in mycelial growth of the pathogen. Neem presented higher disease incidence control in the seedlings of cv. Valença and basil on the seedlings of cv. Santa Cruz 47.

Rot disease is responsible for serious economic losses related to okra (Abelmoschus esculentus) crops cultivated in Upper Egypt. Colonies with a consistent morphology were isolated from the infected okra stems and leaves and subjected to morphological and molecular examinations. The causal pathogen was identified as Cochliobolus spicifer based on morphological fungus descriptions, as well as on the amplified 28S rDNA and internal transcribed spacer region (ITS) sequences, which showed 99%–100% similarity to the sequences of C. spicifer-CSN-20 strains. The volatile and non-volatile organic compounds (VOCs and n-VOCs, respectively) produced by the endophytic fungi that are associated with the medicinal plant Solenostemma arghel, namely Fusarium solani-F4-1007, Penicillium verrucosum-F2-1006, and Aspergillus terreus-F5-1008, inhibited the growth of the C. spicifer pathogen by 34.2%,31.4%, and 30.5%, respectively. In total,27 VOCs were identified by GC/MS, among which eight were specific to A. terreus-F5-1008, eight to P. verrucosum-F2-1006, and three to F. solani-F4-1007, whereas nine VOCs were commonly produced by the three endophytic fungi. Moreover, F. solani-F4-1007-produced VOCs and n-VOCs exhibited the highest antifungal activity, with 37.27% and 37.1% inhibition against C. spicifer colony growth, respectively. The potent antifungal VOCs produced by F. solani-F4-1007 were identified as 3,4-dihydro-2 h-1,5-(3″-t-butyl) benzodioxepine, 4-(2-hydroxyethyl) phenol, and phenylethyl alcohol using GC/MS. Therefore, F. solani-F4-1007 was tested as a potential biocontrol agent against C. spicifer-CSN-20 using an in-planta assay. Okra plants treated with endophytic F. solani-F4-1007did not show any disease symptoms, whereas those that were not treated with F. solani-F4-1007 exhibited severe disease symptoms when challenged with inoculation of the C. spicifer pathogen. Our results demonstrated the contribution of the endophytic fungus F. solani-F4-1007 as a potential biocontrol agent against the C. spicifer pathogen, to improve okra growth.

This study was conducted to collect local Okra (Abelmoschus esculentus L.) genotypes belonging to Malvaceae (Mallow) family in the Northern Cyprus and morphological characterization of this collected material. On the other hand, due to the limited studies on collection and morphological characterization, which are the first step of breeding; the genetic potential of the local okra genotypes of Northern Cyprus has not been determined before. This research was carried out in two stages as the collection and morphological characterization of genotypes. In the first stage of the study, it was aimed to collect local okra genotypes and a total of 58 different locations were reached in line with this target and 24 samples of okra genotypes were collected from these areas. In the second year of the study, morphological characterization studies of 24 okra genotypes from the collected genetic material were carried out according to UPOV and IPGR criteria. As a result of morphological characterization showed that 24 okra genotypes can be categorized under 6 different groups. The regenerated seeds of these 6 different genotypes were preserved. In conclusion, although morphological characterization analyses performed in this study are the methods used to differentiate new species from each other, but it will be insufficient alone. Therefore, it is concluded that this method will be used in coordination with molecular characterization studies to provide more reliable results.

Seed priming is an effective, eco-friendly method to promote seed germination and seedling vigor of okra to overcome the reduced and delayed germination in fresh or stored okra seeds caused by seed hardness. An experiment was carried to evaluate the effects of different priming on okra seeds germination and seedling vigor using Arka Anamika variety at Horticulture lab of Agriculture and Forestry University, Rampur, Chitwan, Nepal. Investigation was carried out with 6 treatments (T1: seed priming with tap water, T2: seed priming with 200ppm NAA solution, T3: seed priming with 10% PEG-200 solution, T4: seed priming with 200ppm GA3 solution, T5: seed priming with 5% Trichoderma solution and T6 no priming) with 4 replications in Complete Randomized Design (CRD). Seeds primed with T1 to T5 were soaked for 24 hours and shade dried for 6 hours before sowing. Priming with T4 was found to be best in terms of maximum seed germination (60.12%), seed vigor index (5772.68 cm), mean germination rate (7.53 seeds per day). The highest shoot length (81.40 mm) was observed at T1 whereas enhancement of root length occurred with the priming with T3. All treatments had a significant positive effect on all the germination parameters in comparison to control. The study concluded that GA3 priming enhanced germination as well as seed vigor in okra and hydro priming and tricho-priming can be used as an alternative to GA3 priming among farmers in Nepal.

Okra (Abelmoschus esculentus L. Moench) is a vegetable crop of high nutritional value, which presents great losses after harvest when stored under poor storage conditions. The objective of this research was to evaluate the effect of different low-density polyethylene (LDPE) thicknesses on the preservation and post-harvest quality of okra fruits under different storage periods. The experiment was conducted in a completely randomized design, with nine replicates, in a 5 × 5 factorial scheme, corresponding to five forms of packaging at a temperature of 10 ± 1 ℃: no film and four LDPE thicknesses (10, 20, 30, and 40 µm) with five storage periods (0, 7, 14, 21, and 28 days). It was revealed that the use of LDPE plastic films provided lower loss of mass, higher fruit firmness containment of increase in soluble solids, and lower color change at 21 days of storage compared to no film. The LDPE thickness of 30 µm showed lower incidence of rotting, better appearance throughout storage, lower color changes, containment of increase in soluble solids content, higher chlorophyll, ascorbic acid, and total phenolic content compared to other forms of packaging, and is the most appropriate package for storing okra fruits up to 21 days, under refrigeration condition. The results of this study show that the thickness of LDPE has significant effects on the conservation and quality of okra. Our findings can be used to minimize post-harvest losses of okra during marketing.

Effect of the application of individual and combination of vermicompost, NPK along with H2O2 was studied on 10, 20, 30, and 40 days old seedlings of Abelmoschus esculentus. The physio chemical characters of soil with vermicompost showed better result and it has all kinds of nutrient needed for the better growth of the crop. It increases soil fertility, crop production and nutrient content of the plants. Integrated fertilizer application will boost the crop and this is the best way to obtain better results and it will decrease the pollution load on our environment. Application of H2O2 also influences the germination, early plant growth and nutrient content. It act as a growth promoter, but the continuous application and accumulation leads to damages, and the disease resistance against pathogens was decreased during the reproductive stages.

Salinity is one of the most devastating abiotic stresses that limit plant growth and yield, especially in arid and semi-arid regions. The objective of this study was to evaluate the effect of foliar application of salicylic acid in mitigating the effects of salt stress on okra cultivation in a hydroponic system. The study was conducted in a greenhouse, consisting of two experiments. A completely randomized design was adopted in a split-plot scheme, with four levels of electrical conductivity of the nutrient solution—EC (2.1; 3.6; 5.1, and 6.6 dS m−1) considered the plots and four salicylic acid concentrations—SA (0, 1.2; 2.4, and 3.6 mM), the subplots, with four replications. The second experiment differed from the first only by the increase in the EC levels (3.0, 5.0, 7.0, and 9.0 dS m−1). An increase in the electrical conductivity of the nutrient solution negatively affected the physiology and production components of okra. However, foliar application of salicylic acid at concentrations between 1.2 and 2.3 mM reduced the harmful effects of salt stress. The salinity threshold for hydroponic cultivation of okra was 2.54 dS m−1, with a reduction of 7.98% per unit increment in EC above this level.

Okra (Abelmoschus esculentus L.), a tropical annual crop, is a highly perishable vegetable. Okra pods deteriorate rapidly after harvesting. The pods undergo physical and physiological changes that diminish storability and quality. The purpose of this study was to investigate the effect of bio-stimulants on the storability and quality of okra pods stored at 4 °C and 25 °C for 12 days. Dipping okra pods for 5 min in a solution of 0.5% ascorbic acid, citric acid, or salicylic acid pre-storage significantly extended the shelf life and preserved the quality of the pods compared to the control condition at 4 °C and 25 °C. Citric acid and ascorbic acid were the most effective in preserving most traits. Citric acid reduced the loss in weight, firmness, appearance, and prevented decay at 4 °C and 25 °C. Ascorbic acid decreased the loss of moisture and the degradation of carbohydrates, vitamin C and lycopene at 4 °C and 25 °C. Salicylic acid decreased the degradation of protein at 25 °C. The low temperature was highly effective in decreasing the loss or degradation of most of the studied traits. Taken together, bio-stimulants and storing at 4 °C played a prominent role in extending the shelf life and preserving the quality of okra pods.

Beneficial soil microorganisms influence nutrient recycling, soil fertility, plant growth, and productivity and reduce chemical fertilizer application. This study aimed to isolate bacteria from non-agricultural soils in the Al-Ahsa region and characterize the bacteria with the best biostimulating characteristics at the physiological, biochemical, and molecular level. DPM17, a bacterial isolate, promotes plant growth through phosphate solubilization, nitrogen fixation, and ammonia production. DPM17 also produces the phytohormones, indole acetic acid (IAA; 4.516 μg mL−1) and gibberellin (1.33 µg mL−1), and ammonia (0.06 µg mL−1). Additionally, DPM17 grows in the presence of up to 10% NaCl, indicating its halophilic nature. DPM17 was identified as Bacillus baekryungensis based on comparative sequence analysis of the 16S rRNA gene, and neighbor-joining phylogenetic analyses indicated that DPM17 was 96.51% identified to Bacillus sp. DPM17 inoculation substantially improved Abelmoschus esculentus (okra) root length, lateral root count, and dry weight from 7.03 to 9.41 (p = 0.03), 3.2 to 7.2, and 6 to 13 mg (p = 0.032), respectively. The results suggest that DPM17 enhances plant growth and can be exploited to develop efficient formulations for sustainable agriculture and food security in Saudi Arabia.

O uso de águas salinas na produção agrícola será cada vez mais necessário nas próximas décadas, entretanto, a qualidade pós-colheita, como no quiabeiro, pode ser comprometida devido ao estresse salino e/ou fatores inerentes ao armazenamento e transporte; neste sentido, o desenvolvimento de métodos alternativos de conservação, dentre eles a fermentação láctica pode constituir uma via promissora para manter e até melhorar a qualidade nutricional do quiabeiro. Assim, objetivou-se avaliar os componentes de produção do quiabeiro submetido a diferentes salinidades da água e doses de adubação potássica; visou-se, também, avaliar a conservação por fermentação láctica dos frutos do quiabeiro produzidos sob salinidade da água. O primeiro experimento foi desenvolvido em lisímetros sob condições de campo em Neossolo Regolítico de textura franco-arenosa em Pombal-PB. Adotou-se o delineamento em blocos casualizados em esquema fatorial 5 x 5, testando 5 níveis de salinidade da água de irrigação (0,3; 1,3; 2,3; 3,3 e 4,3 dS m-1) e 5 doses de adubação potássica (75; 112,5; 150; 187,5 e 225 mg de K2O kg-1 de solo) com três repetições. Em seguida os frutos de quiabeiro produzidos sob os distintintos níveis salinos foram armazenados em seis misturas de sais presentes na salmoura de fermentação láctica (100-0-0, 0-100-0, 0-0-100, 50-50-0, 0-50-50 e 50-0-50 de NaCl, CaCl2 e KCl, respectivamente), sob fatorial 5 x 6, com três repetições, no delineamento inteiramente casualizado, cuja qualidade pós-colheita, após o processo de fermentação, foi avaliada mediante as características físico-químicas dos frutos de quiabeiro. A salinidade da água de irrigação afetou negativamente o comprimento médio, peso médio, acidez titulável, razão de sólidos solúveis/acidez titulável e pH dos frutos de quiabeiro. As doses de potássio provocam acréscimos no diâmetro médio de frutos do quiabeiro minimizando os efeitos deletérios da salinidade da água de irrigação. Os teores de vitamina C dos frutos de quiabeiro em conserva não foram comprometidos pelo estresse salino. Dentre as salmouras de fermentação láctica, a formulação contendo a proporção de NaCl:CaCl2 destaca-se com maior acidez titulável e sólidos solúveis dos frutos do quiabeiro em conserva.

From 2014 to 2016, approximately 5% of okra fruit were observed displaying gray mold symptoms at the research field of Jeollabuk-do Agricultural Research and Extension Services, Korea. The symptoms observed were water-soaked, brown or gray spots, and abundant mycelial with conidia appearing on the infected fruit. Initial infection commenced from the base of fruit and gradually moved to the pod, where it finally resulted in collapse. Colonies on potato dextrose agar were gray to grayish brown, felted and cottony expanding 65-80 mm after one week. The fungus formed several black sclerotia ranging 1.0-3.5×0.5-3.0 mm on the Petri dish after two weeks. The conidia were one-celled, ellipsoidal or ovoid, colorless or pale brown, and 6.2-15.4×5.0-10.4 µm. Conidiophores arose solitary or in groups, straight or flexuous, septate, with an inflated basal cell brown to light brown, and measured 85-450×10.0-40.0 µm. On the basis of the morphological characteristics and phylogenetic analyses of internal transcribed spacer rDNA, the fungus was identified as Botrytis cinerea Pers. Pathogenicity of a representative isolate was proved by artificial inoculation, fulfilling Koch’s postulates. To our knowledge, this is the first report on the occurrence of B. cinerea on okra in Korea.

Abstract Purpose In a novel attempt, vermicompost derived from an intransigent and noxious weed salvinia was assessed for its fertilizer value and pest repellent properties. Methods In outdoor experiments which simulated the way vegetables are cultivated by farmers, ladies finger (Abelmoschus esculentus) seeds were germinated and grown in soil supplemented with salvinia vermicompost at four levels: 0 (V0), 2.5 (V1), 3.75 (V2) and 5 (V3) t/ha. Besides assessing germination success and subsequent growth, yield, and biochemical content of the plants, the impact of pest attacks on them was also studied. Results Salvinia vermicompost significantly enhanced germination success, growth, and yield of the plants. Maximum growth in terms of shoot length (96.2 cm), root length (48.2 cm), shoot and root dry weight (23.31, 7.96 g), stem diameter (14.04 mm), and number of leaves and branches (26.8, 4.8) was recorded in V4 (5t/ha). Likewise, the mineral and biochemical content in vermicompost-treated plants was significantly higher than in the controls. The vermicompost also induced resistance in plants against pests and disease. Compared to the controls, vermicompost had reduced the fruit borer infection by 65, 78 and 82% in V1, V2 and V3, respectively. Conclusion The toxicity of salvinia is largely eliminated when it is vermicomposted, and the product acquires the qualities of a good organic fertilizer. The present work can potentially lead to the development of an inexpensive, sustainable and eco-friendly method of utilizing billions of tons of phytomass that is generated annually by salvinia, and which presently goes to waste.

The little-known use of okra grafting, mainly to incorporate nematode resistance, requires evaluation of interspecific compatibilities. This study aimed to determine the compatibility of the okra ‘Santa Cruz 47’ cultivar grafted onto different rootstocks of the Malvaceae family. The research was divided into two experimental stages, with the treatments consisting of non-grafted, self-grafted or grafted okra plants onto rootstocks of mallow, roselle and pima cotton. In the first stage, a completely randomized design was used, with four replications and seedlings grown in a humidity chamber. In the second stage, the seedlings were transplanted to a greenhouse and a randomized block design was used, with five replications. The results of the first stage demonstrated that the self-grafting provided the best results for the growth characteristics assessed, except for the diameter of the grafted region. There was no difference among the treatments for the graft survival rate. In the second stage, the use of roselle as a rootstock enabled an adequate vegetative development, but did not differ from the treatments of self-grafting and mallow rootstock for the graft survival rate. The treatments did not differ for fruit diameter, length and average mass. Grafts onto roselle were the most precocious ones, with estimated means for production per plant (478.75 g), commercial yield (10.07 t ha-1) and total yield (10.64 t ha-1) similar to those observed for self-grafted and non-grafted plants. Hence, among the assessed rootstocks, roselle was identified as the most promising one for grafting with okra.

Abstract: The objective of this work was to estimate the damage caused by Meloidogyne enterolobii in okra (Abelmoschus esculentus) and to verify the reliability of the reproduction factor as a suitable measure for selecting resistant okra genotypes. Increasing populations of M. enterolobii - 0, 500, 1,500, 3,000, 5,000, and 7,000 eggs and second-stage juveniles (J2) per plant, - were evaluated, in a completely randomized design. The pathogen showed a parasitism pattern similar to that of M. incognita, causing a significant decrease in morphological and agronomic traits. The pathogen reproduction factor should be used in the selection of okra genotypes for tolerance to M. enterolobii, in populations above 3,000 eggs or J2.

ABSTRACT: In an experiment on organic production of okra (Abelmoschus esculentus (L.) Moench) that was carried out from September 2013 to January 2014, in Manaus, Amazonas state, Brazil, we observed large chlorotic, necrotic, helical, discontinuous, dark or light-brown lesions with partial detachment of the injured area on the adaxial surface of leaves located in the median and basal portions of the plants. A whitish mycelium mantle covers the lesions on the leaves at the abaxial surface at high moisture conditions. Using morphological characteristics, Koch’s postulates, and phylogenetic analyses of the ITS-5.8S rDNA region, we identified that the fungus causing the lesions on the okra leaves was Thanatephorus cucumeris (Frank) Donk (asexual stage of Rhizoctonia solani Kuhn of the anastomosis group AG-1 ID). This is the first report of T. cucumeris causing web blight on okra in Brazil, and probably in the world. So far, T. cucumeris was described on okra only on post-harvest pods rotting and seedlings’ damping off.

Os testes de germinação e de vigor são componentes essenciais do processo de controle de qualidade das empresas produtoras de sementes, e o teste de envelhecimento acelerado é um dos mais utilizados para avaliação do vigor de sementes. Nesse sentido, a pesquisa teve como objetivo estudar a metodologia do teste de envelhecimento acelerado, visando à identificação de diferentes níveis de vigor de lotes de sementes de quiabo (Abelmoschus esculentus (L.) Moench). Para isso, quatro lotes de sementes da cultivar 'Colhe Bem' e cinco lotes da cultivar 'Santa Cruz 47' foram submetidos às seguintes avaliações: germinação, emergência de plântulas, envelhecimento acelerado tradicional e em solução saturada com NaCl (38 e 41ºC durante 24, 48, 72 e 96 horas) e grau de umidade no início dos testes e após a incubação para o teste de envelhecimento acelerado. Os testes de envelhecimento acelerado tradicional e em solução saturada com cloreto de sódio, a 41ºC durante 96 horas, constituem em opções promissoras para detectar diferenças de vigor entre lotes de sementes de quiabo.

The use of bovine manure becomes an useful and economic practice for the small and medium producers of vegetables, and the okra plant normally demands high doses of organic fertilizers. This study was carried out, from January to July 2011, at the Federal University of Paraíba, in Areia city - PB, aiming to evaluate the effect of bovine manure and biofertilizer on the productive behavior of the okra plant. The experimental design used was randomized blocks, with four repetitions in factorial scheme 6 x 2, with the doses factors of bovine manure (0, 10, 20, 30, 40 and 50 t ha-1) with and without biofertilizer. The average mass of commercial fruit of okra, with and without biofertilizer was 18 and 16.5 g, respectively, in the doses of 27.5 and 60 t ha-1 of manure. The number of fruit plant-1 without biofertilizer was 30 fruits plant-1 of okra in the dose of 60 t ha-1 and with biofertilizer, the number of fruits plant-1 was 33 fruits in the dose of 28 t ha-1 of bovine manure. The productivity of commercial fruits of okra without biofertilizer was 20.4 t ha-1 and 22 t ha-1 with biofertilizer, respectively, in the doses of 60 and 31 t ha-1 of bovine manure.

The objective of this work was to evaluate the influence of the pre-soak and of the thermotherapy in the germination and in the energy of the okra seeds (Abelmoschus esculentus) in different stadiums of maturation of the fruit. The design used was the entirely randomized with four repetitions, in a factorial outline 5 x 9, five maturation stadiums (green, semi-hard, hard, dry and dehiscent) and nine treatments pre-germination: pre-soak for immersion of the seeds in water to the temperature of 30ºC for 6, 12 and 24 hours; immersion of the seeds in water to 40, 50, 60 and 70ºC for 3 minutes; thermotherapy for immersion of the seeds in water to the ebullition temperature (97ºC) until cooling and intact seeds (control). The seeds were sowed in paper-towel rolls and they were maintained in camera type BOD regulated to 20-30ºC and photoperiod of 8-16 hours. The okra seeds originating from dry and dehiscent fruits presented larger germination performance. The pre-germination treatments more effective to accelerate the germination of seeds obtained from dry and dehiscent fruits are the pre-soak for 6 hours and thermotherapy at 60 °C for 3 minutes, respectively.O objetivo deste trabalho foi avaliar a influência da pré-embebição e da termoterapia na germinação e no vigor das sementes de quiabo (Abelmoschus esculentus) em diferentes estádios de maturação do fruto. O delineamento foi o inteiramente casualizado com quatro repetições, num esquema fatorial 5 x 9, cinco estádios de maturação (verde, semi-duro, duro, seco e deiscente) e nove tratamentos pré-germinativos: pré-embebição por imersão das sementes em água à temperatura de 30ºC por 6, 12 e 24 horas; imersão das sementes em água a 40, 50, 60 e 70ºC por 3 minutos; termoterapia por imersão das sementes em água à temperatura de ebulição (97ºC) até esfriar e sementes intactas (testemunha). As sementes foram semeadas em rolos de papel-toalha que foram mantidos em câmara tipo BOD regulada a 20-30ºC e fotoperíodo de 8-16 horas. As sementes de quiabo oriundas de frutos secos e deiscentes apresentam maior desempenho germinativo. Os tratamentos pré-germinativos mais eficientes para acelerar a germinação das sementes obtidas de frutos secos e deiscentes são a pré-embebição por 6 horas e a termoterapia a 60ºC por 3 minutos, respectivamente.

An experiment was carried out during the period of November of 2001 to April of 2002 in order to evaluate the effects of sources and doses of organic matter on leaf mineral composition of okra cv. Santa Cruz. The treatments were distributed in a randomized blocks design with four replications with 25 holes with two plants in each plot. The treatments were arranged in a 3x4 factorial design, with three sources of organic matter: cattle manure, chicken manure and caprine manure incorporated at soil in four levels in volume of: 0.0; 5.0; 10.0 and 15.0% of the hole (capacity for 48 liters). Okra plants treated with chicken manure had higher foliar content of calcium, magnesium and phosphorus; with the goat manure the higher content of potassium, and with bovine manure higher values of nitrogen in leaf dry matter of plants, but with no difference among doses of manure.Um experimento foi conduzido no período de novembro de 2001 a abril de 2002, com o objetivo de avaliar os efeitos de fontes e níveis de matéria orgânica sobre os teores foliares de macronutrientes em quiabeiro ‘Santa Cruz’. O delineamento experimental utilizado foi em blocos casualizados, em esquema fatorial, com quatro repetições, com duas plantas por cova e 25 plantas por parcela. Foram utilizadas três fontes de matéria orgânica: esterco bovino, esterco de frango e esterco de caprino, fornecidos em quatro níveis: 0, 5, 10 e 15% do volume da cova com capacidade para 48 litros. O esterco de frango proporcionou maiores teores de cálcio, fósforo e magnésio, o esterco de caprino maior de potássio e o esterco de bovino maiores valores de nitrogênio nas folhas das plantas de quiabeiro, mas sem definição estatística de doses entre as distintas fontes de matéria orgânica.

O trabalho foi conduzido na FCA-UNESP, em Botucatu (SP), objetivando-se estudar o efeito da idade do fruto e o período de repouso pós-colheita sobre a qualidade de sementes de quiabeiro cv. Santa Cruz-47 (Abelmoschus esculentus Moench.). No dia da antese, as flores foram etiquetadas e os frutos foram colhidos com 34, 41, 48 e 55 dias após a antese (DAA). Para cada idade, em metade dos frutos as sementes foram extraídas imediatamente e a outra metade ficou em repouso por quatorze dias, antes da extração das sementes. Para verificar a qualidade das sementes os seguintes testes foram realizados: teor de água no dia da extração das sementes, massa de 100 sementes, teste de germinação, primeira contagem do teste de germinação e condutividade elétrica. Pode-se concluir que o armazenamento para qualquer idade do fruto melhora o vigor das sementes. Para germinação final, o armazenamento é favorável quando os frutos são colhidos ainda novos (34 e 41 DAA).The work was carried out at FCA-UNESP, in Botucatu (SP), with the aim of studying the effect of fruit age and post harvest rest on quality of okra seeds cv. Santa Cruz-47 (Abelmoschus esculentus Moench.). At the day of the anthesis, the flowers were labeled and fruits were picked with 34,41,48 and 55 days after the anthesis (DAA). For each age, in half of the fruits the seeds were immediately extracted and the another half was stored for fourteen days before seed extraction. To verify the quality of seeds the following tests were accomplished: seed water content at extraction, weight of 100 seeds, germination test, first counted of germinated seeds and eletrical conductivity. It may be concluded that the fruit storage for any fruit age increases seed vigour, and for final germination, the rest is favorable when fruits are picked still new (34 and 41 DAA).

A influência de quatro épocas de plantio (15 de maio, 15 de junho, 15 de julho e 15 de agosto de 1998) no desenvolvimento e na produção do quiabeiro (Abelmoschus esculentus (L) Moench) (cv. Santa Cruz 47) foi investigada em Goiânia, GO. O experimento foi conduzido na Escola de Agronomia e Engenharia de Alimentos da Universidade Federal de Goiás, em Latossolo Vermelho Amarelo, cultivado há muitos anos. O delineamento experimental foi o de blocos casualizados com quatro repetições. Foram encontradas diferenças significativas (Tukey 5%) entre épocas de plantio, para as seguintes características: número de frutos produzidos durante as trinta primeiras colheitas, altura das plantas no início da colheita, número de ramos laterais e número de dias da semeadura ao início do florescimento, ao início da colheita e ao início da colheita em 75% das covas. A temperatura média dos meses seguintes às datas de plantio aumentou de maio para agosto. Observou-se uma redução do período da semeadura até o início do florescimento, até o início da colheita e até o início da colheita em 75% das covas. O número de ramos laterais também foi reduzido no mesmo período. Entretanto verificou-se aumento na altura das plantas e no rendimento das primeiras trinta colheitas. PALAVRAS-CHAVE: Abelmoschus esculentus; data de plantio; épocas de plantio. The influence of four sowing dates (May 15th, June 15th, July 15th and August 15th, 1998) on the growth and yield of okra (Abelmoschus esculentus (L.) Moench) (cv. Santa Cruz 47) was studied in Goiânia-GO. The experiment was conducted at the 'Escola de Agronomia e Engenharia de Alimentos, Universidade Federal de Goiás', on an oxisol which had been cropped for several years. The experimental design was a randomized block with four replications. Significant differences (Tukey 5%) were found among sowing dates for the following traits: number of pods yielded during the first thirty harvests (105 days), plant height at the beginning of harvest, number of lateral branches, number of days from the sowing to the beginning of flowering, number of days from the sowing to the harvest of the first pod and number of days from the sowing to the beginning of harvest on 75% of the hills. The average temperature of the months following the sowing dates increased from May to August. The period from the sowing to the beginning of flowering, the beginning of harvest and the beginning of harvest on 75% of the hills was shortened and the number of lateral branches decreased from May to August. At the same time, the plant height and the yield of the first thirty harvests increased.KEY-WORDS: Abelmoschus esculentus; planting date; development yield.

The control of Aphis gossypii Glover (Hemiptera: Aphididae) on okra Abelmoschus esculentus (L.) (Malvaceae) consist primarily in the use of insecticides, due to the lack of information on other mortality factors. The objective of this study was to determine the effects of predators and parasitoids, height of canopy, plant age, leaf areas, organic compounds leaves, levels of leaf nitrogen and potassium, density of leaf trichomes, total rainfall and median temperature on attack intensity of A. gossypii on two successive A. esculentus var. Santa Cruz plantations. Monthly number estimates of A. gossypii and natural enemies (visual inspection) occurred on bottom, middle and apical parts of 30 plants/plantation (one leaf/plant). Plants senescence, leaf areas and natural enemies, mainly Adialytus spp., spiders and Coccinellidae, were some of the factors that most contributed to aphid reduction. A higher number of aphids was found on the bottom part than medium and apical parts of okra plants. Total rainfall can reduce the aphid population. Trichomes non-glandular or low density, organic compounds leaves and levels of N and K were not important for reducing aphid population.O controle de Aphis gossypii Glover (Hemiptera: Aphididae) em quiabeiro Abelmoschus esculentus (L.) (Malvaceae) consiste principalmente no uso de inseticidas, em virtude da falta de informação sobre outros fatores de mortalidade. Objetivou-se com este estudo determinar os efeitos de predadores e parasitóides, altura de dossel, idade da planta, área foliar, compostos orgânicos foliares, níveis de nitrogênio e potássio, densidade de tricomas, pluviosidade e temperatura na intensidade de ataque de A. gossypii em dois cultivos sucessivos de Abelmoschus esculentus var. Santa Cruz. Estimou-se, mensalmente, o número de A. gossypii e de inimigos naturais (inspeção visual) ocorridos nas folhas (uma folha/planta) localizadas nas partes basal, mediana e apical de 30 plantas/plantação. Os fatores que mais contribuíram com a redução da população de pulgões foram a senescência de plantas, área foliar e inimigos naturais, principalmente Adialytus spp., aranhas e Coccinellidae. Maior número de pulgões foi observado na parte basal que na mediana e apical de plantas de quiabeiro. A pluviosidade total pode reduzir a população de pulgões. Tricomas tectores (não-glandulares) ou baixa densidade destes, compostos orgânicos foliares e níveis de N e de K não foram importantes para a redução da população de pulgões.

The control of whitefly Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) on okra (Abelmoschus esculentus L.) consists primarily in the use of insecticides, due to the lack of information on other mortality factors. The objective of this study was to evaluate the spatial and temporal population dynamics of the whitefly B. tabaci biotype B on two successive A. esculentus var. "Santa Cruz" plantations. Leaf chemical composition, leaf nitrogen and potassium contents, trichome density, canopy height, plant age, predators, parasitoids, total rainfall and median temperature were evaluated and their relationships with whitefly on okra were determined. Monthly number estimates of whitefly adults, nymphs (visual inspection) and eggs (magnifying lens) occurred on bottom, middle and apical parts of 30 plants/plantation (one leaf/plant). Plants senescence and natural enemies, mainly Encarsia sp., Chrysoperla spp. and Coccinellidae, were some of the factors that most contributed to whitefly reduction. The second okra plantation, 50 m apart from the first, was strongly attacked by whitefly, probably because of the insect migration from the first to the second plantation. No significant effects of the plant canopy on whitefly eggs and adults distribution were found. A higher number of whitefly nymphs was found on the medium part than on the bottom part.O controle da mosca-branca Bemisia tabaci (Gennadius) biótipo B (Hemiptera: Aleyrodidae) em quiabeiro (Abelmoschus esculentus L.) consiste principalmente no uso de inseticidas, em virtude da falta de informação sobre outros fatores de mortalidade. O objetivo deste trabalho foi compreender a dinâmica populacional, espacial e temporal da mosca-branca em dois cultivos sucessivos de quiabeiro "Santa Cruz". Avaliaram-se a composição química foliar, os níveis foliares de nitrogênio e de potássio, a densidade de tricomas, a altura de dossel, a idade de planta, predadores, parasitóides, pluviosidade total, temperatura média e suas relações com a mosca-branca em quiabeiro. Estimou-se, mensalmente, o número de adultos e de ninfas (inspeção visual) e de ovos (lentes de aumento) de mosca-branca ocorridos nas folhas (uma folha/planta) localizadas nas partes basal, mediana e apical de 30 plantas/plantação. Os fatores que mais contribuíram com a redução da população mosca-branca foram a senescência de plantas e inimigos naturais, principalmente Encarsia sp., Chrysoperla spp. e Coccinellidae. O segundo cultivo de quiabo, a 50 m do primeiro, foi altamente atacado pela mosca-branca, provavelmente pela migração dos insetos do primeiro para o segundo cultivo. Não foi detectado efeito significativo do dossel de plantas sobre ovos e adultos. Foi encontrado maior número de ninfas na parte mediana do que na parte basal das plantas.

The aim of this study was to identify the defoliating lepidopterans and their parasitoids occurring on okra plants in the district of Riberão Preto city (SP. Brazil). Caterpillars were collected by hand from an experimental field of okra, in March and April, 2009. They were placed individually on Petri dishes lined with wet filter paper, containing shredded okra leaves, and kept in a climactic chamber (25±1°C, 12:12h light/dark photoperiod, RH 70±10%) until the emergence of lepidopterans and/or parasitoids. In all, 63 lepidopterans were obtained: three species of Noctuidae, Anomis flava (Fabricius), Spodoptera frugiperda (Smith) and Pseudoplusia includens (Walker); one of Pieridae, Ascia monuste orseis (Godart), and an unidentified species of Tortricidae. One unidentified tachinid fly (Diptera) and the Hymenoptera parasitoids Copidosoma floridanum (Ashmead) (Encyrtidae) and Euplectrus sp. (Eulophidae) emerged from A. flava, while C. floridanum and an unidentified tachinid, from P. includens. This is the first report of an association between the herbivores S. frugiperda, P. includens and A. monuste orceis, the parasitoids C. floridanum and Euplectrus sp. on okra plants.Este estudo objetivou identificar lepidópteros desfolhadores e seus parasitoides em cultura de quiabo em Ribeirão Preto, SP, Brasil. As lagartas foram coletadas através de catação manual entre março e abril de 2009, individualizadas em placas de Petri forradas com papel filtro umedecido contendo pedaços de folhas de quiabo e mantidas sob condições controladas (25±1°C, 12 horas de fotofase, 70±10% de UR) até a obtenção dos adultos de lepidópteros e/ou de seus parasitoides. Foram obtidos 63 adultos de lepidópteros: três espécies de Noctuidae, Anomis flava (Fabricius), Spodoptera frugiperda (Smith), Pseudoplusia includens (Walker), uma de Pieridae, Ascia monuste orseis (Godart) e uma de Tortricidae não identificada. Uma espécie não identificada de taquinídeo (Diptera) e os Hymenoptera parasitoides Copidosoma floridanum Westwood (Encyrtidae), Euplectrus sp. (Eulophidae) emergiram de A. flava e, C. floridanum e uma espécie não identificada de taquinídeo, de P. includens. Este é o primeiro relato da associação entre S. frugiperda, P. includens e A. monuste orceis e seus parasitoides C. floridanum e Euplectrus sp. em plantas de quiabo.

Foram estudados em casa de vegetação alguns parâmetros de crescimento em plantas de quiabo (Abelmoschus esculentus (L.) Moench cv. Piranema) colonizadas por dois grupos de fungos micorrízicos arbusculares, com o objetivo de determinar a influência dos inóculos na nutrição e morfologia radicular do quiabeiro. Um grupo continha apenas esporos de Acaulospora longula (A) enquanto o outro, esporos de oito espécies: Glomus occultum, Glomus aggregatum, Glomus microcarpum, Acaulospora longula, Acaulospora morrowae, Sclerocystis coremioides, Sclerocystis sinuosa, Scutellospora pellucida. As plantas foram submetidas a três níveis de P (0, 10 e 60 kg ha-1 de P2O5) e coletadas em três diferentes idades (22, 32 e 47 dias), com quatro repetições para cada tratamento. Foi determinado o acúmulo de N, P, K, e Mg na raiz e parte aérea, bem como o influxo médio desses elementos e a área radicular. Os resultados indicaram, além da resposta positiva do quiabeiro ao P, uma maior eficiência da inoculação com mistura de espécies apesar de o influxo médio, determinado aos 47 dias, apresentar maiores valores para o tratamento com A. longula.An experiment was carried out in greenhouse to determine the influence of inoculation of two groups of arbuscular mycorrhizae on the nutrition and radicular morphology of the okra plant (Abelmoschus esculentus (L.) Moench cv. Piranema. One group had only Acaulospora longula spores and the other a spore mixture of eight species: Glomus occultum, Glomus aggregatum, Glomus microcarpum, Acaulospora longula, Acaulospora morrowae, Sclerocystis coremioides, Sclerocystis sinuosa, Scutellospora pellucida. The experiment was held in greenhouse conditions with three levels of P (0, 10 and 60 kg ha-1 of P2O5), three samplings dates (22, 32 and 47 days) and four replications. The accumulation of N, P, K, Ca and Mg in roots and shoots, root area and their influx ratio were determined. The results made evident that the mixture of species was more efficient although there were higher ratios of influx with Acaulospora longula between 0 and 47th. day.

Devido as vantagens que o sistema apresenta, a produção de mudas utilizando bandejas de isopor, cada vez mais vem sendo utilizada no estado de São Paulo. O sistema proporciona maior cuidado na fase de germinação e emergência, fazendo com que, muitas vezes, uma semente origine uma planta, além de proporcionar menor custo no controle de pragas e doenças e alto índice de pegamento após o transplante. Com o objetivo de avaliar o desenvolvimento de mudas de quiabeiro, cultivar Santa Cruz - 47, produzidas no sistema de bandejas de isopor, montou-se um experimento, em ambiente protegido. Foram comparados três tipos de bandeja, que diferiam entre si pelo volume a altura das células, associadas a quatro diferentes substratos. Os substratos constaram de variações de uma mistura comercial, produzida pela Empresa Gioplanta. O delineamento experimental foi de blocos inteiramente casualizados, com 4 repetições, no esquema fatorial 3X4. Para as condições do experimento concluiu-se que as bandejas de maior volume proporcionaram melhor desenvolvimento das mudas de quiabeiro para todos os parâmetros estudados. No substrato que recebeu casca de arroz carbonizado na proporção 1:1, observou-se menor desenvolvimento das mudas. A utilização do produto comercial (adubado) com suplementação de nutrientes favoreceu o desenvolvimento das mudas de quiabeiro.

A ocorrência de sementes duras em quiabeiro (Abelmoschus esculentus (L.) Moench) foi estudada em função da colheita única dos frutos na senescência das plantas ou da colheita periódica dos frutos no estádio de maturação morfológica. As cultivares utilizadas foram "Amarelinho", "Santa Cruz-47" e "Campinas-2 IAC 4076" e os frutos foram separados em aqueles provenientes da haste principal e os oriundos dos ramos laterais. A porcentagem de sementes duras foi avaliada por meio do teste padrão de germinação e os dados obtidos permitiram verificar que o método de colheita única aumentou a ocorrência de sementes duras e, pelo fato de "Amarelinho" não apresentar essa característica, esse método pode ser utilizado para a mesma, com redução nos custos de produção de sementes sem afetar sua qualidade.The occurrency of hard seeds was studied in okra (Abelmoschus esculentus (L.) Moench) as a function of single fruit harvesting after plant senescence or periodical fruit harvesting in the morphological ripening stage. The cultivars "Amarelinho", "Santa Cruz-47" and "Campinas IAC 4076" were utilized, considering fruits beared on the main stem and those beread on lateral branches. The percentage of hard seeds was evaluated by the standard germination test and it was observed that single fruit harvest after plant senescence increased the occurrence of hard seeds independently of the utilized harvesting method. The possibility of taking advantage of single fruit harvesting during plant senescence is suggested, which will reduce seed production costs without interfering on seed quality.

Este experimento foi conduzido no município de Ituverava, Estado de São Paulo para estudar a freqüência, tipo de coleta (néctar ou pólen) dos insetos e horário de abertura e fechamento das flores em uma cultura de quiabo, Abelmoschus esculentus (Malvaceae) var Chifre-de-veado, bem como o efeito dessas visitas na produção de frutos. Para isso, foram realizadas observações dos insetos no decorrer do dia (das 7h00 às 18h00); marcados os botões florais, com acompanhamento de seu desenvolvimento. Para se observar a taxa de frutificação, 10 botões florais foram protegidos com sacos de papel e comparados à mesma quantidade de botões florais mantidos desprotegidos, com livre acesso dos insetos. As flores do quiabeiro iniciaram sua abertura entre 9h40min e 10h00 e seu fechamento entre 14h45min e 15h20min, do mesmo dia, quando começavam a murchar. Os únicos insetos observados na cultura coletando néctar foram Hymenoptera (Melípona sp.) e Lepidoptera. Para a coleta de pólen, os insetos mais freqüentes foram Thysanoptera, Formicidae, Coleoptera, Hymenoptera (Melípona sp. e Apis mellifera). A cultura apresentou 100% de autofecundação, não necessitando da presença de agentes polinizadores para produzir frutos. Entretanto, flores visitadas por insetos apresentaram frutos mais pesados, mais largos e mais longos

Avaliou-se o efeito de doses de nitrogênio sobre o rendimento do quiabeiro cultivar “Santa Cruz”. O experimento foi conduzido na Universidade Federal da Paraíba, em Areia, de abril a outubro de 2002, no delineamento experimental de blocos casualizados, com cinco tratamentos (0; 50; 100; 150 e 200kg ha-1 de N), na forma de sulfato de amônio, em quatro repetições. Foram utilizadas parcelas de 20 plantas, 2 plantas/cova espaçadas de 1,00m x 0,50m, as quais foram uniformemente adubadas com fósforo, potássio e 20 t.ha-1 de esterco bovino. As características avaliadas foram influenciadas pelos tratamentos. O comprimento dos frutos aumentou de forma linear em função da elevação das doses de N, sendo o mais elevado valor (14cm) obtido com a dose de 200kg ha-1 N, situando-se dentro do limite para frutos especiais. A produção máxima de frutos comerciais por hectare (16.701kg ha-1) foi obtida com 141kg ha-1 de N, enquanto a dose de 140kg ha-1 de N foi responsável pela produção máxima de frutos comerciais por planta (833g). A dose mais econômica foi 133kg ha-1 e a receita prevista devido a aplicação de N foi 8.453kg ha-1 de frutos.