The Editorial Board of Acta Scientiarum. Agronomy would like to thank the referees listed below for their critical appreciation of articles submitted for Volume 37, n. 1 (2015).

This study aimed to investigate the effects of growth regulators on germination rates and biochemical compound concentrations in Carica papaya L. seeds (‘Formosa’ group). The seeds were harvested from fruits at maturation stages 3 and 5 (50 and 75% yellow fruit skin, respectively). The effects of 2-chloroethylphosphonic acid (CEPA), KNO 3 and gibberellic acid (GA 3 ) on seed germination, germination index speed, soluble sugars, starch, lipids, soluble proteins and total proteins of the papaya seeds were evaluated. The seeds from stage 5 showed a higher rate of germination 30 days after sowing than did the seeds from stage 3. Treatment with CEPA decreased seed germination, apparently due to decreased starch mobilization; the opposite response was observed following KNO 3 treatment. GA 3, alone or in combination with KNO 3, stimulated an increase in lipid mobilization. In general, with the exception of CEPA, all growth regulators tested were effective in overcoming seed dormancy, and KNO 3 was the most effective. The seeds from stage 3 fruits treated with KNO 3 or KNO 3 + GA 3 had higher rates of germination at 14 days. | O objetivo deste trabalho foi investigar o efeito de reguladores de crescimento na germinação e na variação de alguns compostos em sementes de Carica papaya L. grupo “Formosa”, extraídas de frutos nos estádios de maturação 3 e 5, correspondendo a 50 e 75% da casca com cor amarela, respectivamente. Avaliaram-se os efeitos do ácido 2-cloroetilfosfônico (CEPA), KNO 3 e GA 3 na germinação, índice de velocidade de germinação, no conteúdo de açúcares solúveis, amido, lipídios, proteínas solúveis e totais das sementes. As sementes-controle obtidas de frutos no estádio 5 apresentaram maior germinação aos 30 dias após a semeadura em relação às do estádio 3. O CEPA promoveu diminuição na germinação das sementes, aparentemente, associado com a redução da mobilização de amido, sendo revertida com KNO 3 . O GA 3 , isoladamente e em associação com o KNO 3 , promoveu maior mobilização de lipídios. Em geral, com exceção do CEPA isoladamente, todos os reguladores de crescimento testados foram eficientes na superação da dormência. O KNO 3 mostrou-se o composto mais eficiente em aumentar a germinação. Sementes do estádio 3 tratadas com KNO 3 ou KNO 3 +GA 3 apresentaram maior germinação aos 14 dias.

The fungus Pochonia chlamydosporia is one of the most studied biological agents used to control plant-parasitic nematodes. This study found that the isolates Pc-3, Pc-10 and Pc-19 of this fungus promote the growth of tomato and lettuce seedlings. The isolate Pc-19 colonized the rhizoplane of tomato seedlings in only 15 days and produced a large quantity of chlamydospores. This isolate was able to use cellulose as a carbon source, in addition to glucose and sucrose. Scanning electron microscopy (SEM) revealed that hyphae of the P. chlamydosporia isolate Pc-10 penetrated the epidermal cells of the tomato roots. These three P. chlamydosporia isolates promote the growth of tomato and lettuce. | O fungo Pochonia chlamydosporia é um dos mais estudados agentes de controle biológico de fitonematoides. Neste estudo foi demostrado que os isolados Pc-3, Pc-10 e Pc-19 do fungo promovem o crescimento de plântulas de tomate e alface. O isolado Pc-19 colonizou o rizoplano de mudas de tomate em apenas 15 dias e produziu grande quantidade de clamidósporos. O isolado foi capaz de utilizar celulose como fonte de carbono, tanto quanto glicose e sacarose. Em estudos realizados por microscopia eletrônica de varredura (MEV), foi possível observar que hifas do isolado Pc-10 penetraram as células epidérmicas das raízes de tomateiro. Os três isolados de P. chlamydosporia promovem o crescimento de tomateiro e alface.

This study establishes a protocol for the induction of somatic embryogenesis in Anthurium andraeanum cv. Eidibel. The experiment was arranged in a completely randomized 5 x 5 x 5 factorial design using five explant types (whole leaves, half leaves; petiole; nodal segments and root segments) from in vitro plantlets; five auxins: indole-3-acetic acid (IAA), α-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA), 2,4-dichlorophenoxyacetic acid (2,4-D), and 4-amino-3,5,6-trichloropicolinic acid (Picloram); at five concentrations (0, 2.5, 5, 7.5 and 10 µM), with five replications using five Petri dishes. The cultures were maintained in a growth room at 25 ± 2ºC in the dark. The explant type was investigated for the induction of somatic embryogenesis in anthurium cv. Eidibel, and nodal segments were shown to be the most suitable explant for this process. After 60 days in culture, the highest number of embryogenic calli was recorded for the nodal segments cultured in NAA (5, 7.5 and 10 µM), 2,4-D (10 µM) and Picloram | O objetivo foi estabelecer um protocolo para indução de embriogênese somática em Anthurium andraeanum cv. Eidibel. O experimento foi arranjado em delineamento inteiramente casualizado, com esquema fatorial 5 x 5 x 5, cinco explantes (folha inteira e seccionada ao meio; pecíolo; segmento nodal e de raiz); cinco auxinas (AIA, ANA, AIB, 2,4-D e Picloram) em cinco concentrações (0,0; 2,5; 5,0; 7,5 e 10 µM) e cinco repetições, consistindo de cinco placas de Petri, mantidas em sala de crescimento a 25 ± 2 ºC, no escuro. Após 60 dias de cultivo, a maior produção de calos embriogênicos foi registrada nos segmentos nodais cultivados na presença de ANA (5; 7,5 e 10 µM), 2,4-D (10 µM) ou Picloram (7,5 e 10 µM). As análises histológicas confirmaram a presença de embriões com polaridade definida, procâmbio, meristema fundamental e protoderme em segmentos nodais cultivados em meio Pierik com 10 µM ANA. Depois da conversão dos embriões somáticos, as plantas foram aclimatizadas e transferidas para as condições in vivo, com crescimento normal das mesmas.

Orchids have become an important portion of the international floriculture market.  Arundina graminifolia is a terrestrial orchid that produces attractive flowers, and, although the species could be a potential candidate for the floriculture market, its considerable height makes it difficult to transport and commercialize.  A number of plant growth regulators have been utilized to control plant height in ornamentals and other species.  Thus, the aim of this study was to evaluate the efficiency of growth regulators, paclobutrazol and chlormequat chloride on the vegetative development of containerized A. graminifolia orchid aiming at height control.  Paclobutrazol (Cultar) was applied at 0, 5, 10, and 20 mg L-1, and CCC (Cycocel) was applied at 0, 2000, 4000, and 6000 mg L-1. The plants were assessed monthly for the plant height and number of shoots per container. CCC had no effect on the final height of plants at the concentrations applied. In contrast, paclobutrazol was effective in controlling plant height at a concentration of 5 mg L-1, but higher concentrations (10 and 20 mg L-1) proved to be toxic to the plants, causing death to the new shoots. Paclobutrazol at lower concentrations offers a viable means for height control in A. graminifolia.

Aiming to evaluate the effects of doses silicon and phosphorus on the phosphate nutrition and production in bean plants, two experiments were conducted in a greenhouse using two soils, Orthic Quartzarenic Neosol (RQo) and Dystroferric Red Latosol (LVdf). Each soil was subjected to three incubation sequences: the first with lime to raise the base saturation to 50%, the second with silicic acid, Si with three doses (0, 240 and 410 and 0, 330 and 560 mg dm-3, respectively, for RQo and LVdf) and the third with basic fertilisation, including phosphorus at four different doses (0, 80, 240 and 410 and 0, 110, 330 and 560 mg dm-3 for RQo and LVdf, respectively). The experiment was performed using a completely randomised 3 x 4 factorial, with four replications. The application of Si did not influence the dry matter production of the aerial part (APDM) or the grain dry matter (DGM) and P accumulation in the aerial part of the bean plants, yet the higher doses of Si increased the accumulation of Si in the APDM. The application of P increased the yield of the APDM and DGM and phosphorus accumulation in the APDM of the bean plants.

The custard apple (Annona squamosa L.), also known as the sugar apple, is a fruit species native to Brazil that has been poorly studied, especially in relation to the effect of humic substances on its fruit quality and yield. An experiment was conducted from December 2010 to November 2011 to evaluate the fruit quality and yield of the custard apple as a function of nitrogen fertilising and the use of humic substances. The experimental design consisted of randomised blocks, with treatments distributed in a factorial arrangement (4 x 2), using four nitrogen doses (0, 100, 175 and 250 g of N plant-1) and two humic substance applications (with and without humic substances), with four replications. The fruit yield and fruit characteristics, such as fruit mass, titratable acidity (TA), soluble solids (SS), pulp pH and SS/TA ratio, were recorded. The humic substances and the nitrogen levels significantly affected the soluble solids, titratable acidity and SS/TA ratio, while the pH pulp was only influenced by the humic substances. The humic substances promoted a quantitative increase in the fruit yield of 0.63 ton ha-1. The fruit quality and yield of the custard apple depend on the nitrogen fertiliser and the interaction of the humic substances. Nitrogen fertilising of 100 g per plant, associated with humic substances, could be recommended for use in the production of custard apples.

Quickly and precise evaluations of the vigor of seeds are highly desirable for the success of quality control programs applied to the seed industry. The objective of this experiment was to determine the number of days necessary to calculate the vigor index of common bean seeds using an automated system of seedling images (SVIS®), and compare its results with the traditional tests of seed vigor. Samples of five seed lots of the IAC Carioca cultivar were submitted to germination, accelerated aging, seedling emergence in sand and electrical conductivity tests. The parameters measured by the Seed Vigor Imaging System (SVIS®) were mean seedling length, growth (ratio of the actual seedling growth to the maximum possible growth), uniformity of growth and the vigor indexes 30:70, 40:60, 50:50, 60:40 and 70:30 (based on different growth/uniformity ratios), and computed from scanned images of three- and four-day-old seedlings.  Results of SVIS® analyses were consistent with the physiological potential evaluations provided by the traditional tests of seed vigor. Therefore, the SVIS® is efficient for detecting differences in vigor among seed lots of common bean (IAC Carioca cultivar) using three- or four-day-old seedlings, independently of the growth/uniformity ratios used to calculate the vigor index.

Diatraea saccharalis is the principal pest of sugarcane in Brazil and is found throughout the sugarcane crop. Information about its population genetics is scarce, but population genetic analysis is of particular importance as a basis for a successful pest control program. Pest control requires a constant evaluation of genetic variability so that appropriate strategies can be employed. In this study, the structure of D. saccharalis populations in sugarcane crops was analyzed with PCR-RAPD (Polymerase Chain Reaction-Random Amplified Polymorphic DNA) markers. Samples were collected from four sugarcane fields in ParanáState and one in São PauloState. Twelve PCR-RAPD primers were used. The analysis produced 216 fragments, with a 99.54% polymorphism rate. The Shannon index averaged 0.3797 (± 0.1729), and the average value of GST for the five populations was 0.0909. These results showed that the populations are differentiated. An analysis of molecular variance showed that 92% of the polymorphism occurs within populations. The high polymorphism rate within these populations shows that these insects have the potential to develop resistance to insecticides. The control and management of D. saccharalis should be conducted cautiously

This study establishes a protocol for the induction of somatic embryogenesis in Anthurium andraeanum cv. Eidibel. The experiment was arranged in a completely randomized 5 x 5 x 5 factorial design using five explant types (whole leaves, half leaves; petiole; nodal segments and root segments) from in vitro plantlets; five auxins: indole-3-acetic acid (IAA), α-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA), 2,4-dichlorophenoxyacetic acid (2,4-D), and 4-amino-3,5,6-trichloropicolinic acid (Picloram); at five concentrations (0, 2.5, 5, 7.5 and 10 µM), with five replications using five Petri dishes. The cultures were maintained in a growth room at 25 ± 2ºC in the dark. The explant type was investigated for the induction of somatic embryogenesis in anthurium cv. Eidibel, and nodal segments were shown to be the most suitable explant for this process. After 60 days in culture, the highest number of embryogenic calli was recorded for the nodal segments cultured in NAA (5, 7.5 and 10 µM), 2,4-D (10 µM) and Picloram (7.5 and 10 µM). The histological analysis confirmed the presence of embryos with established polarization, procambium, ground meristem and protoderm in the nodal segments cultured in Pierik medium containing 10 µM NAA. After the conversion of the somatic embryos into plantlets, these plantlets were acclimatized transferred to in vivo conditions and grown into normal plants.