Resumo em Inglês:

ABSTRACT The refrigerated induce the sweetening of the potato, which results in the dark color. The objective of this study was to determine the temperature and shelf life of Markies potato tubers under refrigerated storage for the processing of French fries. The levels of total soluble sugar (TSS), reducing sugars (RS), peroxidase (POD) and polyphenoloxidase (PPO) activity, color after frying and start of sprout were determined. The accumulation of TSS started at 30 days in the tubers at 4 and 5 °C and in the tubers at 6 and 8 °C, at 150 days. The activity of POD and PPO were not influenced by temperature or storage time. Tubers at 4 e 5 °C showed higher TSS and RS contents and darker color after frying than tubers stored at 6 and 8 °C which had their color maintained within the industry-acceptable standard up to 240 days of storage. Temperatures of 4 and 5 °C delayed the onset of sprouting, starting at 150 days, and at temperatures of 6 and 8 °C, the onset of sprouting occurred from 90 and 60 days of storage, respectively. It is concluded that the cultivar Markies should be stored at 6 °C for 240 days.

Resumo em Inglês:

ABSTRACT Ginger (Zingiber spectabile) is cultivated worldwide as a floriculture and landscaping species. Studies on the biology and floral morphology of this species are important for its improvement; however, they are scarce. We investigated the reproductive biology and floral morphology of gingers grown in a germplasm bank. Floral development was monitored during the pre-anthesis and anthesis periods. Floral morphometry, pollen viability, stigmatic receptivity, volume and concentration of nectar sugar, and performance of possible pollinators were evaluated. Ginger flowers had a 24-h durability. Ginger torch is an allogamous species that exhibits floral hercogamy like other Zingiberaceae. Ginger flowers had a 12-h anthesis. During anthesis, floral structures related to reproduction such as the style, stigma, and anther crest continued to develop, increasing floral herkogamy. Pollen viability was above 70% and the stigma remained receptive throughout the anthesis period. Hummingbirds were the only pollinators recorded in the study area that were able to move the anther crest. Fruiting was determined in a natural pollination system. The occurrence of nocturnal anthesis characterized by an increase in the development of reproductive structures and nectar production suggests that the species is adapted to nocturnal visitors.

Resumo em Inglês:

ABSTRACT The successful use of native species in conservation actions depends on basic knowledge of their biology, beginning with the identification of regenerating individuals in the field, up to the behavior and development of the species from the early stages of germination. Moreover, seed propagation and germination may be limited by the occurrence of dormancy. The objective of this work was to identify the best method to overcome seed dormancy of Hymenaea parvifolia Huber, besides characterizing the fruits, seeds, post-seminal development and seedlings of naturally occurring specimens in Amazonia. For this, (i) tests for the breakdown of dormancy were performed through thermal, chemical and mechanical treatments; (ii) analyses of their effects on seed germination were made; and (iii) morphology of germinative development of Hymenaea parvifolia was described. The treatments based on sulfuric acid for 15, 25 and 35 minutes were the most efficient in overcoming the integumentary dormancy. However, scarification by grinding is recommended because it had been less impact on the environment. External characteristics and shape of the fruit, seed and epicotyl can aid taxonomy of the genus and identification of its species in the field. In addition, morphological characters of the fruit, seed, germination and seedling were illustrated.

Resumo em Inglês:

ABSTRACT The objective of this study was to evaluate the virulence of Pyricularia oryzae isolates obtained from a single leaf blast lesion on wheat. The wheat cultivars (BRS Louro, BR 18, BRS Tarumã, BRS Parrudo, BRS 208) at the four-leaf stage were inoculated with a suspension of 100.000 conidia/mL. A significant difference was observed in the severity in the cultivars. Among the evaluated isolates, it was possible to observe differences in the susceptibility of the cultivars. Severity data ranged from 3.3 to 99.54% among treatments. Isolates 1 and 2 were the most aggressive for all cultivars tested. The greatest disease severity occurred in the interactions BRS 208 x isolate 1 (99.54%), BRS Louro x isolate 2 (99.34%), and BRS 208 x isolate 2 (99.09%).The lowest disease severity was observed in BRS Tarumã (68%) and BR 18 (75%) cultivars for the isolates 1 and 2, respectively. Isolate 3 presented medium aggressiveness in which the cultivars presented between 44 to 58% of wheat blast severity. The isolate 4 was the least aggressive for all cultivars with severity indexes ranging from 3 to 12%. These data indicate the existence of virulence diversity in P. oryzae isolates obtained from a single lesion.

Resumo em Inglês:

ABSTRACT Despite the important role of coffee production in the economy of Espirito Santo, the second largest coffee producing state in Brazil, productivity is still below the Brazilian average. One of the factors that explain this low productivity is the presence of nematodes of the genus Meloidogyne. Contaminated seedlings are an important and efficient agent for disseminating nematodes. According to normative instruction no. 35 (IN 35), of 11/29/2012 of the Ministry of Agriculture, Livestock and Supply (MAPA), the presence of Meloidogyne spp. in a single plant among a field-lot of seedlings condemns it, and the plants that compose that lot should be destroyed. In Espirito Santo, no evaluation has been carried out in nurseries covering the entire State for phytonematode detection. Therefore, the objective of this work was to carry out a nematological survey in nurseries to guide the nurserymen in relation to fulfilling IN 35 of MAPA, in addition to guiding them regarding the phytosanitary care during the production of their seedlings. The nurseries were evaluated in 19 municipalities located in both the north and the south of Espírito Santo. There were Meloidogyne spp. in evaluated samples.

Resumo em Inglês:

ABSTRACT The objectives of this work were to determine the optimum plot size for tomato seedlings by Hatheway’s method, using the Mestiço and Ozone cultivars, and verify the possibility to obtain the optimum plot size only by non-destructive characteristics. Non-destructives (aerial part height, stem diameter, number of leaves and leaf area) and destructives (aerial part dry matter, root dry matter, total dry matter and Dickson quality index) characteristics were evaluated. For each characteristic evaluated, experimental plans were simulated in a randomized block design with the combination of I treatments (I = 3, 4, 5, ..., 10, 15, 20 and 25) and R repetitions (R= 3, 4, 5, 6 and 7). The optimum plot size ranged according to the characteristic evaluated. Considering the number of treatments, repetitions and the same experimental accuracy, the stem diameter showed the highest size plot. Thus, the stem diameter can be used as a basis characteristic for the non-destructives characteristics, without the need to destroy the seedling.

Resumo em Inglês:

ABSTRACT In this study, we evaluated the adventitious rooting competence of mini-cuttings and plantlet growth of two clones of swamp cork (Erythrina crista-galli L.). Experiments were carried out in a factorial of two clones to study the need of application of indolebutyric acid (IBA), substrate composition for mini-cutting rooting and plantlet growth, and rooting curves of the clones 15SM05 and 15SM08, in the completely randomized design. Mini-cuttings of swamp cork clones showed high rooting competence, with mean rooting percentage above 80% even without IBA application. Vermiculite and its combination with commercial substrate resulted in the highest percentage of rooting, and number and length of roots and shoots. The clones showed differences regarding their adventitious rooting competence and the increment in rooted mini-cuttings with time in a humidity chamber, being the clone 15SM05 the most suitable for plantlet production.

Resumo em Inglês:

ABSTRACT Bauhinia scandens is an ornamental plant and it has anti-tumor properties. The demand for seedlings of this species makes it necessary to know about the germinative behavior of seeds and the initial growth of seedlings. The objective of the present work was to determine the type of substrate and moistening conditions that are more favorable to the emergence and development of seedlings of B. scandens. B. scandens seeds were disposed on three substrates: sand, vermiculite, and commercial substrate, maintained at four levels of moistening 25, 50, 75, and 100% of the water holding capacity of the substrate and kept in a greenhouse for 60 days. The following parameters were evaluated: emergence, speed index, average time, number of leaves, length of aerial part and root, diameter of neck, fresh and dry mass of aerial part and root. The analysis of variance was performed in a completely randomized design, in a 3 X 4 factorial scheme, with four replications of 25 seeds. The sowing of B. scandens should be carried out initially in vermiculite with a holding capacity of 100% until the establishment of the seedling emergence and then transplanted to commercial substrate keeping between 50 and 75% holding capacity.

Resumo em Inglês:

ABSTRACT Several studies have demonstrated the importance of Pindo palm in Rio Grande do Sul and Brazil, mainly through preservation but also due to the economic potential of using its fruit. In collections of Pindo palm fruit carried out in some regions of Rio Grande do Sul, the presence of beetle larvae inside of seeds was observed. This study aimed at identifying the species and evaluating the level of infestation of this insect in Pindo palm endocarps. Endocarps were kept in observation in the laboratory to verify the emergence of adults. The number of endocarps with the presence of the exit hole of the adult insect was registered. Afterwards, the endocarps were broken, and the number of adult insects, larvae and intact seeds was registered. The insect that occurred in the Pindo palm trees was identified for the first time in the country, at the species level, as Pachymerus bridwelli (Prevett, 1966). Infestation occurred in 75.1% of the endocarps. Among the damaged ones, the occurrence of only one larva was verified in 75.7%. However, it was also possible to verify the presence of two larvae (22.1%) and up to three larvae (2.2%) per endocarp. The loss of seeds reached 53.4%.

Resumo em Inglês:

ABSTRACT Chia is a plant whose seeds are used in cooking and is a natural source of omega-3 fatty acids, fiber and protein, as well as other important nutritional components such as antioxidants. The objective of this work was to estimate the base temperature, plastochron and chia seed yield for different sowing times in Cruz Alta, Rio Grande do Sul, Brazil. The experimental design was completely randomized and the treatments consisted of different sowing times (September, October and November). For the determination of the base temperature for node emission in the main stem of the plants, the method of least mean square error of linear regression between the number of nodes and the accumulated thermal sum was used. Regarding estimation of the plastochron at each sowing time, a simple linear regression was obtained between the number of nodes in the main stem and the accumulated thermal sum. Seed yield was measured at harvest. Sowing in times with air temperature below 19 ºC should be avoided so that the development of plants is not impaired. Plastochron ranges from 28.01 ºC to 32.26 ºC day for successive node emission in the main stem of chia plants and September sowing promotes higher seed yield.