Teste de raios x na avaliação da qualidade de sementes de abóbora

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Maturação de sementes de aveia-preta (Avena strigosa Schreb). II. Maturidade da panícula e da espigueta

The present work aims at defining the panicle and spikelet maturity of Avena strigosa Schreb. Four experiments were carried out under field conditions during 1989 (E1 and E2) and 1990 (E3 and E4) in Botucatu county, São Paulo State, Brazil. The sowings were made in 04.19.89 (E1) and 06.18.89 (E2). Maturity of panicle was evaluated by weekly (E1) or biweekly harvests (E2) beginning at total emergence of the panicle. In E3 and E4, sowing was made in 06.04.90 and each experiment had a single harvest date (E3 = 11.01.90 and E4 = 11.07.90). After harvest, the spikelets with similar stage of development were grouped and evaluated. Based on dry matter accumulation and germination percentage of the seeds, it was observed that the maturity of the seeds in the panicle was reached at 28 and 35 days after total emergence of the panicle in the April sowing, and between 24.5 and 28 days in the June sowing. During this period a few percentage of panicles not yet yellow became all yellow, the cariopsis at semi-hard stage became hard and moisture of the seeds dropped from 32% to 12%. The maturity of the seeds in the spikelet was reached when the glumes changed their color from yellowish to yellow, the lemma and palea changed from yellow with black strips to black, the cariopsis changed from farinaceous stage to semi-hard and the moisture content of the seeds changed from 40% to 25%.

Condutividade elétrica na solução de embebição de sements de soja. I. Efeito do genótipo

During the period from October/92 to September/94 experiments were carried out at the Seed Laboratory, FCAV/UNESP, Jaboticabal, SP, Brazil, using soybean seeds of different genotypes in order to evaluate the effect of genotype on the electrical conductivity (bulk conductivity) of soaked seeds. Seed moisture content (105+/-3 degrees C, 24 h), standard germination (four 50-seed samples, paper towel, 30 degrees C), and vigor-accelerated aging (42 degrees C, 48 h) were first determined. Undamaged soybean seeds were soaked in deionized water (four 50-seed samples, 75 ml, 25 degrees C, 24 h) and electrical conductivity (mu mhos.cm(-1).g(-1)) was measured. Significant differences in conductivity were observed among genotypes having the same pattern of germination and vigor. The results have showed that electrical conductivity can be significantly influenced by genotype.

Qualidade fisiológica de sementes de Sebastiania commersoniana (Baill.) Smith & Downs (branquilho - Euphorbiaceae) durante o armazenamento

This paper aims to evaluate the physiological quality of Sebastiania commersoniana seeds stored in cloth bag, plastic bag and glass container and kept in two conditions: laboratory workbench and cold chamber (4 ± 2°C e 80% relative humidity - RH) for 531 days. Periodically, samples were taken in order to determine the moisture content and to perform germination tests. The experimental design was completely randomized, in factorial scheme of 3 × 2 (wrappings × conditions), for each period of storage evaluated (0, 158, 271, 389 and 531 days of storage). Supplementary, a polynomial regression was adjusted in order to describe the physiological quality of the seeds for the different conditions during the experimental period. The results lead to the following considerations: a) storage under variable temperature and air humidity (laboratory workbench) can be used for periods of over five and a half months, with the seeds stored in cloth bag, plastic bag or glass container; b) the physiological quality of the seeds was not hardly altered when stored in cold chamber in cloth bag, plastic bag and glass container for over 18 months.

Doses de composto orgânico, com e sem fósforo adicionado ao solo, na produção e qualidade de sementes de alface

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Doses e épocas de adubação nitrogenada e poda apical na produção e qualidade das sementes de quiabeiro

Pós-graduação em Agronomia - FEIS

Doses de fósforo no acúmulo de nutrientes, na produção e na qualidade de sementes de alface

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Foreign agriculture circular.

Title from caption.

Year book and proceedings of the annual convention

1908 report includes Topical index of annual reports from 1883 to 1907 inclusive and Proceedings of Congress of horticulture, Jamestown exposition, Sept., 1907

Polinização por Apis mellifera em soja em soja transgênica [Glycine max (L.) Merrill] Merrill] Roundup ReadyTM cv. BRS 245 RR e convencional cv. BRS 133.

RESUMO: O objetivo deste estudo foi verificar a influência de Apis mellifera na produção de grãos e qualidade de sementes da soja transgênica Glycine max (L.) Merrill Roundup ReadyTM e convencional. A soja transgênica foi plantada intercalada com a convencional, em 18 parcelas, em três tratamentos: gaiolas com abelhas A. mellifera, gaiolas sem abelhas e áreas descobertas, com livre visitação de insetos. Na soja transgênica, em três parcelas de cada tratamento, foi aplicado glifosato, 30 dias após a emergência. Os parâmetros analisados foram: produção de grãos; número de vagens por planta; peso de 100 sementes e porcentagem de germinação das sementes. Não houve diferença entre as cultivares, entretanto a produção de 2.757,40 kg ha-1 obtida na área coberta por gaiola com abelhas, e 2.828,47 kg ha-1 na área livre para visitação de insetos foram superiores a 2.000,53 kg ha-1 da área coberta por gaiola sem abelhas. O número de vagens por planta foi maior na área coberta por gaiola com abelhas (38,28) e área livre (32,65), quando comparado com o da área coberta por gaiola sem abelhas (21,19). O peso médio de 100 sementes e a germinação das sementes não foram diferentes entre as cultivares e nem entre os tratamentos. Conclui-se que, para as cultivares estudadas, houve benefício na produção de grãos de 37,84%, quando foi permitida a visita de abelhas. ABSTRACT. Pollination by Apis mellifera in transgenic soy (Glycine max (L.) Merrill) Roundup Ready? cv. BRS 245 RR and conventional cv. BRS 133. This research was carried out to evaluate the influence of Africanized honeybees in grain production and seed quality of Glycine max (L.) Merrill Roundup Ready? transgenic soy, as well as of conventional soy. Transgenic soy was interposed with conventional soybean, in 18 plots and three treatments: covered area with Africanized honeybees, covered area without honeybees, and uncovered area with free insect visitation. The herbicide Glyphosate was applied on three plots of each treatment of transgenic soy, 30 days after emergence. Grain production, number of pods/plant, weight per 100 seeds, and seed germination percentage were evaluated. There was no difference among cultivars; however, the production in the covered area with honeybees (2757.4 kg ha-1) and in the uncovered area (2828.47 kg ha-1) were higher than in the covered area without honeybees (2000.53 kg ha-1). The number of pods/plant was greater than in the covered area with honeybees (38.28) and in the uncovered area (32.65) as compared to the covered area without honeybees (21.19). The weight per 100 seeds seed germination did not differ among cultivars or treatments. It can be concluded that, for these cultivars, there was a rise in grain production of 37.84% when honeybee visits were allowed.

Accelerated ageing test to evaluate seed vigor in pumpkin and zucchini seeds

The accelerated ageing (AA) test is widely used to evaluate seed vigor in various species including vegetable crops. The objective of this work was to study procedures for conducting AA to evaluate seed vigor of pumpkin and zucchini seed lots. Five seed lots of commercially acceptable quality (germination) standards were selected from both cv. `Menina Brasileira' (zucchini) and `Barbara' Hybrid (pumpkin). The following tests were conducted: standard germination, the first count of germination, and AA with and without saline solution (periods of 48, 72 and 96 hours). For each combination of temperature and ageing period, seeds were placed in a single layer on a screen in a germination plastic box with either 40 mL deionized water or 40g NaCl/100mL of water. Both AA methods identified lots 2 and 5 of `Menina Brasileira' and lot 10 of `Barbara' hybrid as having the lowest physiological quality. The temperature 41 C promoted a more drastic reduction in germination than did 38 C. This observation was more marked after 96 hours. Based on the results obtained, it can be concluded that the combination 41 degrees C/96 hours should be used to evaluate the physiological potential of pumpkin and zucchini seeds; however, additional studies are necessary to evaluate other combinations and confirm this indication.

Seed size and genotype effects on maize (Zea mays L.) yield under different technology levels

Final plant population in maize crop was used as a basis to identify the technology level of a given farmer. Final population of 50,000 plants/hectare was considered as an indication of a high technology level farmer; 35,000 of a medium, and 20,000 of a low technology level farmer. These populations were artificially obtained for the hybrids HT-2X, BR-201, and BR-205 from small, medium and large seeds. The results showed the triple cross hybrid HT-2X to be the most indicated for low technology level regions, due to its lesser sensitivity to variations in seed size and also to its significant outyielding of the other two hybrids. The double cross hybrids BR-201 and BR-205 exhibited much higher sensitivity to variations in seed size so that if they have to be used in a low technology region, the most recommended procedure would be to make use of the largest possible seeds. In conclusion, genotype and seed size seem to be factors capable of compensating for plant population reductions in maize crops. The more prolific hybrids and the largess seeds are more indicated for low technology level regions.

Broad Bean Stain Virus: Identification, Detectability with ELISA in Faba Bean Leaves and Seeds, Occurrence in West Asia and North Africa and Possible Wild Hosts

Abstract During a survey of faba bean viruses in West Asia and North Africa a virus was identified as broad bean stain virus (BBSV) based on host reactions, electron microscopy, physical properties and serology. An antiserum to a Syrian isolate was prepared. With this antiserum both the direct double antibody sandwich ELISA (DAS-ELISA) and dot-ELISA were very sensitive in detecting BBSV in leaf extracts, ground whole seeds and germi nated embryos. Sens it i vity was not reduced when the two-day procedure was replaced by a one-day procedure. us i ng ELISA the vi rus was detected in 73 out of 589 faba bean samples with virus-like symptoms collected from Egypt (4 out of 70 samples tested), Lebanon (6/44) , Morocco (017), Sudan (19/254), Syria (36/145) and Tunisia (8/69). This is the first report of BBSV infection of faba bean in Lebanon, Sudan, Syria and Tunisia. speci es i ndi genous to Syri a were Fourteen wild legume susceptible to BBSV infection, with only two producing obvious symptoms. The virus was found to be seed transmitted ~n Vicia palaestina.

Seed Transmission of Broad Bean Stain Virus in the Wild Legume Vicia Palestina Boiss

Abstract Seed-transmissibility of brood bean stain virus (BBSV) was investigated in a number of wild legume species. Genninating axes of seeds coliected from BBSV -infected plants were tested by the enzyme-linked immunosorbent assay (ELISA). The virus was found to be seedtransmitted in Vida pal«stina.

Pseudoseeds : investigating long-distance, ocean seed dispersal with wireless sensors

Recent theoretical research has shown that ocean currents and wind interact to disperse seeds over long distances among isolated landmasses. Dispersal of seeds among isolated oceanic islands, by birds, oceans and man, is a well-known phenomenon, and many widespread island plants have traits that facilitate this process. Crucially, however, there have been no mechanistic vector-based models of long-distance dispersal for seeds among isolated oceanic islands based on empirical data. Here, we propose a plan to develop seed analogues, or pseudoseeds, fitted with wireless sensor technology that will enable high-fidelity tracking as they disperse across the ocean. The pseudoseeds will be precisely designed to mimic actual seed buoyancy and morphology enabling realistic and accurate, vector-based dispersal models of ocean seed dispersal over vast geographic scales.