Adroaldo Guimarães Rossetti

Efeito do congelamento e do tempo de estocagem da polpa de acerola sobre o teor de carotenóides

ABSTRACT - Acerola ( Malpighia glabra L .) is one of the main natural sources of vitamin C and is an excellent source of carotenoids. Due to thevitamin potential of carotenoids, and their possible association with the carcinogenesis process, there is an increasing concern of the scientificcommunity about their chemistry and stability in food. The objective of this research was to study the effect of commercial freezing and storageprocedures on the carotenoid contents (in respect to the vitamin A potential) of acerola pulp. The acerola pulp was processed in a small industry inFortaleza, CE. The carotenoid contents were determined on freshly processed pulp (control), on recently frozen pulp and over time on stored frozenpulp. The β-carotene content of the frozen pulp has decreased 20% after four months of storage, when compared to the control content (7.09 µg/g),but no significant differences existed in the subsequent months. The β-criptoxantin content (1.7 µg/g) decreased 37% in the first month of storage,remaining practically constant until eleventh month, when it totalized a 62% drop. The content of α-carotene in pulp was small. About the vitamin Apotential, the control pulp showed 1338 UI/100g, corresponding to, approximately, 25% of the daily recommendation for this vitamin. After freezing,vitamin A potential was maintained until the third month of storage, when a significant drop of 20% was observed. No significant alterations weredetected in the subsequent months until the end of the evaluation period.

Feno de cunhã (Clitoria ternatea L.) para acabamento de cordeiros

Thirty two crossbred lambs were used in a 70 day study at Embrapa Caprinos, in Sobral, CE, Brazil to evaluate the influence of concentrate levels on finishing diets under confinement. The treatments were the following roughage to concentrate relations: 100% to 0% (T1), 85% to 15% (T2), 70% to 30% (T3) and 55% to 45% (T4). The roughage was cunha hay (Clitoria ternatea L), and the concentrate was composed of corn (75%) and soybean meal (25%). The adjustments of the proportions were made daily, based on the roughage intake, served ad libitum. It was observed that the total dry matter intake increased, the forage intake decreased, the feed efficiency improved and the daily weight gain increased (P 0.05) among treatments. It was concluded that any of the diets studied can be used for finishing lambs.

Efeito de substratos na formação de porta-enxertos de Psidium guajava L. cv. Ogawa em tubetes

The formation of guava rootstocks in root plugs was evaluated in differents substrates: vermiculite + vermicompost, carbonized rice hulls + vermicompost, vermicompost + decompose cashewnut tegument, carbonized rice hulls + cattle manure, carbonized rice hulls + vermiculite and dust peel of ripened coconut fruit + decompose leave dust from carnauba palm tree. The experimental design was completely randomized with 6 treatments, 4 replicates and 14 plants per plot. The plant height, stem diameter and number of leaves were measured in three different periods at 60, 90 and 120 days after sowing. Shoot dry matter and root dry matter mass, the facility to remove the seedling from the root plug and substrates aggregation to root were evaluated at 120 days after sowing. The results showed that guava rootstocks with 120 days provided the taller plant height (30.2 cm), stem diameter (5.3 mm), dry matter mass (5.7g), root dry matter mass (3.0 g) and number of leaves (14.5) in the vermiculite + vermicompost substrate. The easiest substrate to take out the rootstocks from the root plug were achieved using vermiculite + vermicompost, vermicompost + decompose cashwewnut tegument, carbonized rice hulls + vermiculite and carbonized rice hulls + cattle manure. It was observed that all the substrates showed excellent results in substrate aggregation.

Estimates of genetic correlations and correlated responses to selection in cashew (Anacardium occidentale L.)

The present study estimates variances and genetic and phenotypic correlations for five traits in 27 progenies of cashew trees (Anacardium occidentale L.). Data were obtained from a trial conducted in 1992 at Pacajus, Ceara, experimental station of Embrapa Agroindustria Tropical. The characters studied were plant height (PH), North-South and East-West canopy spreads (NSS, EWS), and primary and secondary branch numbers (PBN, SBN). All genetic and phenotypic correlations presented positive and significant values. Selection to increase or decrease the average of any one of the five characteristics of cashew plants in the progenies studied affected the average of the others. The 16-month-old canopy spread can be predicted from NSS or EWS since correlations between them were high. Correlations between PH and SBN were low, indicating that there is a good possibility of obtaining smaller plants without causing drastic reductions in SBN. PH and SBN showed, respectively, the lowest and highest genetic variance estimates relative to the corresponding population means.

Production of strawberry cultivars in closed hydroponic systems and coconut fibre substrate

The objective of this work was to evaluate yield and average fruit weight of strawberry cultivars Albion, Camarosa, Festival and Oso Grande, in two closed hydroponic systems (gutters and grow bags), using coconut fibre as substrate. The experimental design was of randomised blocks, divided into strips, with five replications. The hydroponic systems did not differ significantly as to yield, with advantages, such as savings in water and fertilizer and reduced environmental impact, over open systems. The most productive cultivar was Festival, followed by Oso Grande, with average yields of 6.99 kg m-2 and 5.56 kg m-2 respectively. The cultivars with the greatest fruit weight were Oso Grande and Albion, having averages of 11.8 and 11.1 g respectively, with the former being significantly superior to the latter. The highest yield (7.4 kg m-2) was obtained from the cultivar Festival under the gutter system. The Ibiapaba region has conditions which are favourable to strawberry production in relation to precocity (harvesting starts in the 6th week of growth) and production continues throughout the year; however there is a need to test new cultivars and to improve the cultivation techniques with an aim to producing larger-sized fruit.

Aspectos morfológicos da unidade de dispersão de cajazeira

Morphological features of endocarps of five Brazilian yellow mombin plants were assessed. Plants selected to this study were as follow: Plant 1 (from Caucaia) and plant 2 (from Itaitinga), both in the State of Ceara; plants 3, 4 and 5 (from Areia, State of Paraiba). A total of 500 mature fruits were harvested from each plant, peeled, dried under shade and stored in paper bags. Random samples of 50 endocarps were taken from each batch, and the following charac- teristics were evaluated: weight, length and diameter in the median part, and the number of loci and seeds. Number of loci and seeds per endocarp ranged from two to five, and from zero to five, respectively. Highest frequencies observed were four loci and one seed. Endocarps of yellow mombin exhibit high frequency concerning the presence of more than one seed as well as low sterility.

In vitro culture of Spondias mombin L. nodal segments

Spondias mombin L. shoot cultures were initiated from nodal explants taken from plants propagated by seeds. Explants coming from 4-6 months old plants, previously disinfected, were cultivated on WPM medium supplemented with a wide range of concentrations of BAP (0.0, 0.22, 0.44, 2.22 and 4.44 mM) and NAA (0.0, 0.27 and 2.70 mM). After four weeks, the responses obtained were axillary shoot and root formation. The first response were preferentially induced with the medium containing only BAP, regardless of the BAP concentration. The addition of NAA on medium reduced significantly axillary shoot formation and induced rhizogenesis. Roots were formed on nodal explant basis, preferentially on medium supplemented with 4.44 mM NAA. The medium supplemented with BAP reduced significantly root formation.

Integração de fungicidas à refrigeração no controle de podridão pós-colheita em frutos de meloeiro

Postharvest decay caused by quiescent fungi represents a risk for fresh fruit export. Nevertheless, the number of melon (Cucumis melo) products registered for postharvest treatment is still very low. The objective of this work was to evaluate the influence of three fungicides (thiabendazole, azoxystrobin and imazalil at 30, 10 and 400 g a.i/100 l) on mycelium growth and sporulation of Fusarium pallidoroseum and to compare the effect of these fungicides combined with low temperatures for the control of postharvest fungal pathogens on melons. Thiabendazole and imazalil inhibited 100% of fungal mycelial growth and sporulation while azoxystrobin inhibit 87.09%. Refrigeration inhibited lesion development in melon treated with fungicides and inoculated with 107conidia/ml suspension. All tested fungicides were effective to control the incidence of post-harvested fungal pathogens at room temperature for up to six days of storage. Thiabendazole and azoxystrobin were efficient in reducing severity and lesion size for up to 12 and 16 days of storage, respectively. Under refrigeration, better control was obtained with thiabendazole and imazalil. When withdrawn from a refrigerated environment, the fungicides were able to maintein control until day 20. For severity, azoxystrobin and imazalil differed from the control; for lesion size, only azoxystrobin differed. During 34 days in refrigerated storage, the fungicides controlled equally for incidence and lesion size while for severity, a better control was obtain with thiabendazole and imazalil. Imazalil had the best control of spontaneous lesions that occurred on fruit peciolous.

Efeito do início de ocorrência do míldio na produção de frutos do meloeiro

Downy mildew caused by Pseudoperonospora cubensis is the main disease affecting melon (Cucumis melo) fruit during the rainy period in areas of Northeastern Brazil where the crop is produced. Up to ten fungicide sprays are used throughout the crop season. The establishment of risk analysis for forecast of damages caused by this disease requires an estimate of the losses under different epidemic situations. Three field experiments were carried out to determine the damage caused by downy mildew to the fruit yield of the melon crop. The epidemic was considered to begin in the phenological cycle of the host plant. Different intensities of epidemics were achieved by spraying one of the following fungicide mixtures: methyl thiophanate + chlorothalonil or metalaxyl + mancozeb. There was a significant reduction on the fruit yield when the disease started at 24 and 36 days after planting, but when the disease started on day 47, no effect in production was observed. It was concluded that the duration of the the epidemic and when it began in relation to the cycle of the host, should be considered when establishing prognostic models to describe the risks of yield losses.

Influência do tipo de ramo sobre o crescimento e produção do cajueiro-anão-precoce de copa substituída

Visando a testar a influencia do ramo fornecedor de propagulo para enxertia por borbulhia, no crescimento e producao do cajueiro-anao-precoce, realizou-se um experimento na fazenda Itaueira, municipio de Canto do Buriti, Piaui. O experimento foi instalado em blocos ao acaso, com oito tratamentos: ramo em inicio de floracao sem folha; ramo em inicio de floracao com folha; ramo vegetativo sem folha; ramo vegetativo com folha; ramo com panicula seca sem folha; ramo com panicula seca com folha; ramo com flores abertas sem folha; ramo com flores abertas com folha; quatro repeticoes e de cinco a oito plantas por parcela. Utilizou-se um pomar de plantas de pe-franco, as quais foram decepadas e suas brotacoes enxertadas a pleno sol com propagulos do clone CCP 76. Avaliaram-se, na fase juvenil, o pegamento de enxertia, a altura da planta, a envergadura leste-oeste, e, na fase adulta, a producao: peso e numero de castanha. A analise dos dados permitiu concluir que os melhores tratamentos, da fase juvenil, onde se verificou maior porcentagem de pegamento de enxertia (96%), e as plantas que tiveram melhor desenvolvimento, foram os enxertados com propagulos de ramos com floracao e flores abertas, independentemente de ter ou nao folhas, seguidos dos em inicio de floracao, nas mesmas condicoes. Na fase produtiva, os propagulos de ramos com floracao, cujas producoes nao diferiram entre si, apresentaram-se mais produtivas e significativamente diferentes dos de ramos vegetativos e com panicula seca.