João Paulo Feijão Teixeira

Resistência de soja a Nezara viridula e Piezodorus guildinii em condições de campo

The soybean cultivars Parana. Vicoja and Santa Rosa, the line IAC 73-228 and the introductions PI 171451 and PI 229358,e were tsted in Campinas, State of Sao Paulo, Brazil, in relation to the stink bugs Nezara viridula L. and Piezodorus guildinii Westw. The line IAC 73-228 had the least percentage of damaged seed (48,l%) in the superior half of the plant, whereas Parana had the highest (96,8%). The introductions PI-171451 (71,1%) and PI 229358 (79,1%) had intermediate degrees of damaged seeds. This difference in damaged seeds could be due to actual resistance to the stink bugs, to resistance to Nematospora coryli transmitted by these insects or due to host evasion. It has been observed by DAUGHERTY et al. (1964) and LINK & COSTA (1974), that varieties with shorter period from flowering to harvest are less damaged by stink bugs and this would be a case of pseudo resistance called host evasion according to PAINTER (1951). There was a high positive correlation between percentage of seeds damaged and green stems at harvest. This feature could be used for field selection against these insects. There was positive significant correlation between damage and seed size. The seed size may be linked in some way to susceptibility to stink bugs. The damage was higher in the superior half of the plants than in the inferior.

Cultivo de manjericão em hidroponia e em diferentes substratos sob ambiente protegido

Among the aromatical herbs, basil is of great economic importance in Brazil. This species is used as fresh herb and also for essential oil extraction. To evaluate the productivity of basil in protected environment, two species, Ocimum minimum L. (narrow leaf basil) and Ocimum basilicum L. (wide leaf basil) were cultivated under greenhouse conditions, using a hydroponic system and two types of substrata. The experiment was carried out in a completely randomized design with three repetitions. Samples were obtained during the flowering period. The yield and the chemical composition of the essential oils were evaluated. The highest yield of green mass from the two species, was obtained in the hydroponic system, with higher productivity (aprox. 44%) than the plants cultivated in prepared commercial substratum. Plants of Ocimum minimum L. produced more essential oil (aprox. 10%) than plants of Ocimum basilicum L. Significant differences were found in the chemical composition of essential oil between species. No differences were observed in the chemical composition of essential oil, comparing the three cultivation systems.

Teor e composição do óleo de sementes de Jatropha spp.

Utilizaram-se sementes de Jatropha curcas L., J. mollissima L. e J. podagrica Hook, para avaliacao quanto ao teor e composicao do oleo. Para J. curcas L., houve diferenca quanto ao teor e composicao do oleo em funcao de localidade, tratos culturais e variedades, variando o teor de 23 a 34%, e a composicao do oleo em acido palmitico de 15 a 17%; acido oleico, de 30 a 33%, e acido linoleico, de 42 a 52%. Para J. mollissima, verificou-se diferenca varietal no teor de oleo: sementes de tegumento claro apresentaram 30% e, de cor escura, 20%. O mesmo nao ocorreu para a composicao do oleo, cujos principais componentes foram acido palmitico, 19%, acido oleico, 21%, e acido linoleico, 52%. As sementes de J. podagrica apresentaram o mais elevado teor de oleo, 46%, composto de acido palmitico, 9%, acido oleico, 11 %, e acido linoleico, 77%.

Composição química das sementes de Canavalia gladiata DC

Canavalia gladiata D.C. is commonly used as a green manure crop and its seeds are still seldom used for feeding. The objective of this study was to determine the chemical composition of the seeds in order to evaluate its potential value as a food. The seed dry matter presented the following average composition: crude protein 29%, crude fiber 6%, starch 37%, ether extract 1.5%, nitrogen free extract 62%, and total sugar 7.5%. The aminoacid contents in the protein fraction were: lysine 6.5%, histidine 4%, arginine 6%, tryptophan 2%, treonine 6%, cistine 0.8%, valine 6%, methionine 0.5%, isoleucine 5%, leucine 9%, tyrosine 2% and phenylalanine 5%. The data indicated the seeds of C. gladiata have a potential value as a food, however they need a long cooking period to eliminate toxic compounds.

Ocorrência de glicoalcalóides e esverdeamento em tubérculos de batata recém-colhidos e armazenados

Thirty-six cultivars of potatoes were studied with respect to the total glycoalkaloids (TGA) content and greening capacity of the tuber. The determinations were made in the superficial portion of both newly harvested and tubers stored in the presence or absence of light during 25 days. The TGA content ranged betwen 3-24mg/100g of fresh weight. Both the storage conditions and the cultivars influenced the TGA content and greening capacity. There was a negative correlation between TGA content and the 440nm absorbance of a chloroform extract for newly harvested tubers. This correlation, however, was positive for the stored tubers. The present data suggest that both the TGA content and the greening capacity of the tubers were influenced by genetic characteristics of each cultivar.

Obtenção de amido a partir do colmo de bambu

Bamboo chips (Guadua flabellata Fournier) was desintegrated in presence of cold water (25°C). The starch was isolated by decantation from the material soluble in water. Regarding color, the bamboo starch is similar to the soluble potato starch but its average dimension is smaller.

Acúmulo de matéria seca e nutrientes, em soja cultivar Santa-Rosa

Estudou-se o acumulo de materia seca e a absorcao de macronutrientes pela soja, cultivar santa-rosa, em estadios sucessivos de desenvolvimento. As amostragens da parte aerea foram feitas a intervalos de 20 dias num ensaio em Sao Simao, em latossolo roxo de textura media sob vegetacao de cerrado. O maximo de materia seca acumulada durante o ciclo ocorreu aos 90 dias apos a germinacao e atingiu uma producao de 5632 kg/ha. O mesmo foi observado para calcio, magnesio e enxofre, tendo sido absorvidos ate esta epoca 58,7, 27,8 e 9,3 kg/ha, respectivamente. A absorcao maxima de potassio, de 80,2 kg/ha, ocorreu aos 110 dias, enquanto para o fosforo, 12 9 kg/ha, e para o nitrogenio, 146,1 kg/ha, aos 130 dias coincidindo com o maior desenvolvimento das sementes. Aos 130 dias as sementes continham o maximo de materia seca e macronutrientes. As sementes retiraram 92,5% de N, 83,7% de P, 58,7% de K, 16,0% de Ca, 21,9% de Mg e 43,0% de S em relacao ao total extraido pela planta.

Biochemical and physical modifications of bean seeds during storage

Seeds of dry beans cvs Rico 23 and Carioca, were chemical and physically characterized three times during eleven months of storage. Electrophoresis in polyacrylamide gel with SDS of the globulin fraction showed an increase in the number of bands at the third sampling, probably due to a more efficient protein extraction. However, molecular weight of the G1 and G2 subunits were constant, about 50,000 -43,000 and 18,000, respectively. Total protein, soluble sugars and water contents did not change during storage, while fiber increased and lipids decreased. Starch content, as in case of globulin fraction, also increased due to greater extractability. Both free fatty acids content and peroxide value increased, according to the increase of the acidity value. Water absorption capability increased initially and leveled off thereafter. The percentage of seeds with hard coat was not affected by storage. The behaviour of the two cultivars was very similar.

Avaliação do teor de ureídeos em plantas de confrei

O objetivo deste trabalho foi avaliar o conteudo em nitrogenio proteico, nao-proteico e ureideos (alantoina e acido alantoico) em raizes e folhas de plantas de confrei,(Symphytum officinale L.). Os resultados mostraram que, nas folhas, 12% do nitrogenio era nao-proteico, 28% do qual era de ureideos. Nas raizes, 54% de nitrogenio total era nao-proteico, 71% do qual proveniente de ureideos. Alantoina representou 92% e 79% dos ureideos de raizes e folhas respectivamente.

Acúmulo de substâncias de reserva em grãos de soja. I: matéria seca, óleo e ácidos graxos

No estudo da dinâmica de acumulo de materia seca e lipidios em graos de soja, foram utilizadas vagens de dez cultivares, nos anos agricolas de 1978/79 e 1979/ 80. Os graos foram avaliados semanalmente durante todo o seu periodo de desenvolvimento, quanto aos teores de materia seca, oleo e acidos graxos. Os resultados mostraram que a influencia de anos agricolas sobre o acumulo de materia seca e oleo foi devida principalmente as condicoes do meio verificadas de 20 a 40 dias antes da maturacao dos graos, em 1978/79: 152mm de chuva e 22oC, e em 1979/80: 50,8mm de chuva e 25oC de temperatura media. A velocidade de acumulo de materia seca nos graos foi maior em 1979/80, porem o total de materia seca acumulado, menor: os graos continham 78% do total de materia seca acumulada no ano agricola de 1978/ 79. Para oleo, verificou-se a influencia positiva de temperatura e negativa de precipitacao pluvial na velocidade de acumulo dessa substância durante o periodo de enchimento dos graos. Para o cv Santa Rosa, utilizado como referencia, em 1978/79, os graos atingiram o maior valor aos 80 dias apos o florescimento (DAF) com 22% de oleo, e 1979/80 atingiu o valor maximo de 23% aos 43 DAF. A composicao do oleo em acidos graxos variou durante o desenvolvimento dos graos, tendo os saturados, ao contrario dos insaturados, decrescido. O teor de acido linoleico apresentou correlacao positiva com o teor de oleo, enquanto os de acidos linoleico e linolenico se correlacionaram negativamente com o teor de acido oleico. O maior teor de oleo e os menores de acido linoleico e linolenico estiveram correlacionados com temperatura mais elevada e menor precipitacao pluvial.