Roberta Manica-Berto

Apropriação tecnológica da produção integrada de pêssegos na região de Pelotas no Estado do Rio Grande do Sul

The integrated production of peach (IPP) had its first milestone in Brazil in 1999. This study examined the technological level in which are producers of peach, identifying the rate of adoption of integrated production systems (IP), seeking to highlight the determinants of its validation. For this, a semi-structured questionnaire was performed with 20 peach producers, in which were raised information about the production units regarding its characterization and production technology, in the period from 2006 to 2007. The main factors identified as limiting for the management of IPP were: little knowledge about standard IPP, restricted list of pesticides registered for agriculture use, lack of differentiation and return on peach produced under the rules of IP. The points detected as positive were: identification of increased interest on MIP by producers, with emphasis on: identifying the environmental benefits and protection of the producer, reduction of external inputs (particularly pesticides) and soil management operations.

Phosphate Fertilizer and Growing Environment Change the Phytochemicals, Oil Quality, and Nutritional Composition of Roundup Ready Genetically Modified and Conventional Soybean

Phosphorus (P) intake, genotype, and growth environment in soybean cultivation can affect the composition of the soybean. This experiment was conducted in two locations (microregions I and II) using a randomized complete block design, including conventional soybean (BRS Sambaíba) and genetically modified (GM) [Msoy 9144 Roundup Ready (RR)] cultivars and varying doses of phosphorus fertilizer (0, 60, 120, and 240 kg/ha P2O5). Soybeans were evaluated for chemical composition, total phenols, phytic acid content, individual isoflavone content, antioxidant activity, oil quality, fatty acid profile, total carotenoid content, and individual tocopherol contents. Multivariate analysis facilitated reduction in the number of variables with respect to soybean genotype (conventional BRS Sambaíba and GM Msoy 9144 RR), dose of P2O5 fertilizer, and place of cultivation (microregion I and II). BRS Sambaíba had higher concentrations of β-glucosides, malonylglucosides, glycitein, and genistein than Msoy 9144 RR, which showed a higher concentration of daidzein. The highest concentrations of isoflavones and fatty acids were observed in soybeans treated with 120 and 240 kg/ha P2O5, regardless of the location and cultivar.

Efeito da radiação ultravioleta-C no controle de Monilinia fructicola

A radiação UV-C vem sendo utilizada como método alternativo no controle de doenças na pós-colheita de frutos. A podridão parda é uma das principais doenças que acomete pêssegos desde o início do desenvolvimento até a senescência. Neste trabalho, avaliou-se o efeito da radiação UV-C na indução de resistência à podridão parda de pêssegos cv. Chimarrita, em frutos com e sem ferimentos. As variáveis avaliadas foram a severidade da doença, o teor de compostos fenólicos e a capacidade antioxidante. A aplicação da radiação UV-C, tanto como controle preventivo como curativo, não protegeu o pêssego contra a infecção do patógeno, mesmo em frutos sem ferimento. Entretanto, atrasou em um dia o aparecimento de lesões nos frutos não feridos, o que pode ser interessante economicamente para a cadeia produtiva do pêssego. Ao avaliar o teor de compostos fenólicos totais e a capacidade antioxidante, verificou-se que frutos submetidos à radiação UV-C tiveram incrementos nessas propriedades. Tal fato indica que esse tratamento físico (UV-C) estimula o metabolismo secundário, ao menos da síntese de compostos fenólicos, mas não é suficiente para gerar resistência à podridão.

Diversidade molecular entre populações de Spodoptera frugiperda no Brasil avaliada por marcadores AFLP

O objetivo deste trabalho foi avaliar a diversidade molecular, por meio de marcadores AFLP, de seis populacoes de Spodoptera frugiperda coletadas na cultura do milho, em diferentes regioes geograficas do Brasil. O DNA foi extraido de lagartas de quarto instar, e as reacoes de AFLP foram realizadas com sete combinacoes de oligonucleotideos iniciadores. A partir das seis populacoes de S. frugiperda estudadas, foi identificado um grupo principal formado por tres populacoes geneticamente mais relacionadas. As populacoes de S. frugiperda analisadas mostram alta variabilidade genetica, com maximo de 58% de similaridade.

Resistência de biótipos de arroz-vermelho aos herbicidas imazapyr + imazapic e alternativas de controle

O uso intenso de herbicidas com o mesmo mecanismo de acao na cultura do arroz (Oryza sativa L.) tem selecionado biotipos resistentes, como, por exemplo, o arroz-vermelho (planta daninha) resistente aos herbicidas imidazolinonas. Por essa razao, este trabalho foi desenvolvido com o objetivo de avaliar a resistencia de arroz-vermelho ao herbicida imazapyr + imazapic, na regiao sul do Rio Grande do Sul, e o controle do biotipo resistente de arroz-vermelho com os herbicidas alternativos clethodim e glyphosate. Foram realizados tres experimentos, em delineamento casualizado, arranjados em esquema fatorial. No primeiro experimento, o fator A testou biotipos de arroz-vermelho [ORYSA 184 (resistente) e ORYSA 188 (susceptivel)], o fator B comparou herbicidas (imazapyr + imazapic, clethodim e glyphosate) e o fator C avaliou doses dos herbicidas (0; 0,5; 1; 2; 4; 8; 16 e 32 vezes a dose recomendada). No segundo, compararam-se biotipos de arroz-vermelho e doses do herbicida imazapyr + imazapic (0; 0,5; 1; 2; 4; 8; 16; 32 e 64 vezes a dose recomendada). No terceiro, testaram-se biotipos de arroz-vermelho e doses diferentes do herbicida imazapyr + imazapic para cada biotipo. O biotipo ORYSA 184 e resistente ao imazapyr + imazapic, quando aplicada a dose maxima de registro e estadio indicado. Os herbicidas clethodim e glyphosate, detentores de mecanismos de acao alternativos, controlam o biotipo resistente ORYSA 184 de arroz-vermelho.

Efeito da calagem na lixiviação de imazethapyr e imazapyr em solo de cultivo de arroz irrigado

Imidazolinone herbicides are widely used in rice for the control of major weeds. These herbicides behave as weak acids or bases, depending on the pH which may affect leaching. The objective of this study was to evaluate the effect of liming on imazethapyr and imazapyr leaching. Undisturbed soil samples (pH 4.8) were collected in a rice paddy field without history imidazolinone application. The soil columns, that constituted the experiment units, were collected using a soil extractor constituting. The experiment was conducted in a greenhouse, arranged in a factorial design, begin the factor A included of soil with natural pH and limed soil. Factor B was included the herbicides imazethapyr and imazapyr (all at 100g a.i. ha-1) applied to the surface of the soil columns. Factor C included of sampling depths at the end of the experiment to evaluate leaching (5 by 5cm). The results showed that enhanced pH cause by liming affect herbicide leaching in rice paddy soil. Soil liming enhance imazethapyr and imazapic leaching.

Development of 'Maciel' peach trees on different propagation systems.

The development of new technologies for seedling production is essential in fruit growing. In this context, the objective was to compare vegetative and productive aspects of ‘Maciel’ peach trees and the quality of fruits from plants under different propagation systems. The experiment was carried out in a randomized complete block design with four replications, in a 2 x 3 factorial scheme, two years (2014 and 2015) and three propagation systems (self-rooted ‘Maciel’ (minicutting), ‘Maciel’ with rootstock ‘Okinawa’ (minicutting) e ‘Maciel’ with rootstock ‘Okinawa’ (seed)). The variables evaluated were canopy volume, trunk diameter, yield, productive efficiency, fruit diameter, soluble solids (SS), titratable acidity (TA), SS/TA ratio, pH, pulp firmness, carotenoids, phenolic compounds and antioxidant capacity. The self-rooted ‘Maciel’ peach plants, in the second year of evaluation, present higher canopy volume, trunk diameter and thus, they express higher yield and productive efficiency. Fruit quality how much soluble solids, titratable acidity, SS/TA ratio, pH and pulp firmness are not altered by different propagation systems. The use of different propagation systems over two years modifies the levels of carotenoids and phenolic compounds total and, consequently, the antioxidant capacity of the fruits of ‘Maciel’ peach plants.

Biology and Fertility Life Tables for Palpita forficifera (Lepidoptera: Crambidae) Reared on Three Olive Cultivars and Privet

Abstract Palpita forficifera Munroe, 1959 (Lepidoptera: Crambidae) is the main pest of the olive tree (Olea europaea L. Oleaceae) in Brazil. This study investigated the biology of P. forficifera reared on different hosts and elaborated the corresponding fertility life table for a better understanding of its development. Biology of P. forficifera was studied using olive cultivars Arbequina, Arbosana and Koroneiki and the alternative host privet (Ligustrum lucidum Ait., Oleaceae), under controlled conditions of temperature (25 ± 2°C), relative humidity (60 ± 10%), and photophase (14 h). We evaluated duration and viability of egg, larva, and pupa stages; number and duration of instars; sex ratio; pupa weight; duration of preoviposition, oviposition, and postoviposition periods; fecundity and longevity. The fertility life table was elaborated from these parameters. Larvae fed with privet had longer larval stage, and consequently, egg-pupa period. Larva viability was lower in cv. Arbosana, which reflected in lower viability in the egg–pupa period. Larvae fed with cv. Koroneiki originated females with higher fecundity. From the joint assessment of the biological parameters and the fertility life tables, cv. Koroneiki provided the greatest population increase, while cv. Arbosana impaired P. forficifera development. Thus, in areas of high occurrence of this species, cv. Arbosana should be considered as the more indicated cultivar for the establishment of new olive groves.

QUALITY OF MINIMALLY PROCESSED ‘FUJI’ APPLE UNDER REFRIGERATED STORAGE AND TREATMENT WITH ADDITIVES

The aim of this study was to evaluate the ability to prolong the useful life of the minimally processed ‘Fuji’ apple by applying the individual or combined additives (L-cysteine chloride, L-ascorbic acid and calcium chloride) and to determine the appropriate period of storage of the whole fruit to perform the minimum processing. The experimental design was completely randomized in three-factor design with three replications. Factor A was composed of storage periods of whole apples, pre-processing, in cold chambers (20, 78, 138 and 188 days); the factor B was represented by storage periods minimum post-processing, simulating shelf life (3, 6, 9 and 12 days), and factor C was represented by chemical additives (distilled water, as control, 0.5% L-cysteine chloride, 1% L-ascorbic acid, 0.5% L-cysteine chloride along with 1% calcium chloride and 1% L-ascorbic acid together with 1% calcium chloride). The evaluated dependent variables were pulp color (L* and ho), soluble solids, titratable acidity, content of phenolic compounds, antioxidant capacity and quantification of polyphenol oxidase. In addition, was analyzed the presence or absence of Salmonella sp. and Escherichia coli. The prolongation of the storage time of ‘Fuji’ apples in a refrigerated atmosphere promotes increased susceptibility to browning and softening after processing from 78 days of storage. The use of additives in the process, helps prevent these problems, especially when combined 0.5% L-cysteine chloride with 1% calcium chloride, achieving an excellent conservation in refrigerated shelf up to 6 days. From a microbiological aspect, minimally processed apples are toxicologically safe.