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Erythrina speciosa showed 100 % survival until the 60th day of flooding and was able to recover its metabolism. The recovery during soil flooding seems to be associated with morphological alterations, such as development of hypertrophic lenticels, adventitious roots and aerenchyma tissue, and with the maintenance of neutral amino acids in roots under long-term exposure to root-zone O(2) deprivation.

Pejibaye or peach palm (Bactris gasipaes Kunth) is being cultivated in many countries for heart-of-palm or palmito. The estimated area of pejibaye cultivation in Brazil is over 12,000 hectares. Large amounts of nutrients are exported during harvest, and fast and constant growth is imperative for economic large-scale cultivation; hence, replacement of nutrients, based on adequate fertilization, is essential. It is known that unbalanced fertilization can cause nutritional problems in palms, impairing growth and yield. In order to identify responses of pejibaye to NPK fertilization, a long-term trial is being carried out in Sao Paulo State, Brazil. The experimental design is an (1/2) 43 incomplete factorial, with 32 treatments, with four yearly rates of N (0-400 kg N ha -1 ), P (0-200 kg P 2 O 5 ha -1 ) and K (0-200 kg K 2 O ha -1 ), split into five applications. Data collected from five-year old plants showed that shoot and root biomass varied with NPK fertilizer rates, as did root arbuscular mycorrhizal (AM) colonization. A significant and positive linear effect of N was detected for shoot biomass, whereas for mycorrhizal colonization a quadratic N effect was found. Quadratic effects of P for root biomass and shoot/root biomass were detected. Potassium produced significant negative effects on mycorrhizal colonization and shoot/root ratio, and positive effects on root biomass; a quadratic effect of K was detected on offshoot number. Nutrient interactions were only significant for mycorrhizal colonization (P*K) and for shoot biomass (N*K). Significant positive correlation coefficients were found for AM colonization with root biomass and soil organic matter, while negative correlations were found with soil pH and magnesium content. Root biomass was negatively correlated with soil pH, base saturation, calcium and magnesium. The importance of a balanced combination of macronutrients for the overall growth of pejibaye plants was emphasized. IntroductionPejibaye or peach palm (Bactris gasipaes Kunth) is cultivated in several tropical countries for heart-of-palm production, although heart-of-palm or palmito, can be extracted from other palm genera (Tabora, P.C. et al., 1993). It is basically composed of the unexpanded leaves immediately above the apical meristem. Large-scale pejibaye cultivation aiming heart-of-palm production has some especial characteristics in relation to the cultivation of this and other palms for fruit. It involves periodical and constant harvesting, with plants in a continuous juvenile vegetative stage. The speed with which above-ground biomass is renewed (due to the high suckering capacity of the species) is a good indicator of the productivity and the economic life span of this crop. The area cultivated with pejibaye for heart-of-palm purpose in Brazil is exponentially increasing since 1990 (Bovi, M.L.A., 1997). Nowadays it is estimated as over 12,000 hectares. Different ecological regions are going into cultivation and various degrees of technology and inputs are applied to this new crop...

The Amazonian peach palm (Bactris gasipaes Kunth) has been grown for heart-of-palm production under subtropical conditions. As we did not see any substantial study on its photosynthesis under Amazonian or subtropical conditions, we carried out an investigation on the diurnal and seasonal variations in photosynthesis of peach palms until the first heartof-palm harvest, considering their relationship with key environmental factors. Spineless peach palms were grown in 80-L plastic pots, under irrigation. Gas exchange and chlorophyll fluorescence emission measurements were taken in late winter, mid spring, mid summer and early autumn, from 7:00 to 18:00 h, with an additional chlorophyll fluorescence measurement at 6:00 h. The highest net CO 2 assimilation (P N ), observed in mid summer, reached about 15 μmol m -2 s -1 , which was about 20% higher than the maximum values found in autumn and spring, and 60% higher than that in winter The same pattern of diurnal course for P N was observed in all seasons, showing higher values from 8:00 to 9:00 h and declining gradually from 11:00 h toward late afternoon. The diurnal course of stomatal conductance (g s ) followed the same pattern of P N , with the highest value of 0.6 mol m -2 s -1 being observed in February and the lowest one (0.23 mol m -2 s -1 ) in September. The maximal quantum yield of photosystem II (F v /F m ) was above 0.75 in the early morning in all the months. The reversible decrease was observed around midday in September and October, suggesting the occurrence of dynamic photoinhibition. A significant negative correlation between the leaf-air vapour pressure difference (VPD leaf-air ) and P N and a positive correlation between P N and g s were observed. The photosynthesis of peach palm was likely modulated mainly by the stomatal control that was quite sensible to atmospheric environmental conditions. Under subtropical conditions, air temperature (T air ) and VPD leaf-air impose more significant effects over P N of peach palm than an excessive photosynthetic photon flux density (PPFD). The occurrence of dynamic photoinhibition indicates that under irrigation, peach palms appeared to be acclimated to the full-sunlight conditions under which they have been grown.

RESUMO -O achachairu (Garcinia sp), fruta largamente produzida na Bolívia, vem sendo comercializado no Brasil há vários anos. O fruto é globoso-oblongo, de polpa branca, suculenta e textura mucilaginosa e de sabor doce-acidulado equilibrado ( o Brix 15 e pH 4,1). Devido ao crescente interesse em seu cultivo no Brasil, pesquisaram-se a germinação das sementes e o desenvolvimento das plântulas durante os primeiros 12 meses após sua emergência. As sementes, extraídas de frutos bem maduros, foram postas a germinar em duas situações: 1) ambiente controlado em estufa tipo B.O.D., sob as temperaturas de 25 e 30 ºC, fotoperíodo de 16 horas e irradiância de 32 μmol.m -1 .s -1 , e 2) ambiente de temperatura não-controlada: 3) B.O.D, cuja temperatura oscilava entre 20 e 30 ºC, e 4) sob temperatura ambiente de laboratório (25± 2 ºC). O melhor resultado foi obtido na temperatura constante de 30 ºC, com germinação de 92% e índice de velocidade de germinação (IVG) de 0,255. Quando germinada em ambiente de laboratório, a germinação das sementes mostrou-se baixa (30%), com IVG de 0,015. O desenvolvimento das plântulas em casa de vegetação ocorreu de forma bastante lenta, principalmente nas primeiras semanas após a emergência. O primeiro par de folhas surgiu após três semanas da emergência das plântulas, quando essas mediam 8 cm em média. A partir do oitavo mês de desenvolvimento, as plântulas emitiram várias ramificações laterais a partir da porção mediana para a região apical. Termos para indexação: frutífera, propagação, Clusiaceae, Garcinia sp. SEEDS GERMINATION AND SEEDLINGS EARLY DEVELOPMENT OF ACHACHAIRUABSTRACT -The achachairu (Garcinia sp), a fruit widely grown in Bolivia, has been commercialized in Brazil for many years. The fruit is globular-oblong shaped, with a white succulent pulp, mucilaginous texture and a well balanced sweet-acid flavor ( o Brix 15; pH 4.1). Due to the increasing interest in its cultivation in Brazil, this work was carried out aiming to study the seeds germination and seedling development throughout the first 12 months after seed emergence. The seeds, after being extracted from full ripe fruits were placed in a B.O.D. type chamber, under the following temperatures: 25, 30, 20-30 ºC, as well as under room temperature (25±2 ºC). The best result was given by the steady temperature of 30ºC, with a germination of 92% and a germination speed index (GSI) of 0,255. At room temperature, seeds germination was low (30%), with a GSI of 0,015. Seedling development at greenhouse conditions was very slow mainly throughout the first weeks post emergence. The first pair of leaves appeared 25 days after seedling emergence, when seedlings averaged 8cm. From the eighth month on, many lateral branches were burst out, from the seedling medial portion towards the apical one.

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RESUMOO objetivo deste trabalho foi avaliar o crescimento de mudas de pupunheira quando utilizado o resíduo fino de mineração de areia na composição de substratos. O experimento constou de cinco tratamentos, sendo quatro composições de diferentes proporções de resíduo de mineração de areia e casca de arroz carbonizada: 1:0; 3:1; 1:1; 1:3 e um substrato padrão composto por latossolo amarelo podzólico álico e esterco de búfalo curtido, na proporção 3:1. Utilizou-se o delineamento experimental de blocos ao acaso com cinco repetições e 10 mudas por parcela. Repicou-se uma plântula de pupunheira por recipiente (sacos plásticos de polietileno preto de 8 x 20 cm, volume 1,1 L), os quais foram preenchidos com os diferentes substratos. Foram determinadas mensalmente as variáveis diâmetro do coleto, altura da haste, número de folhas e taxa de crescimento relativo e, após 180 dias da repicagem, os valores SPAD (Soil and Plant Analysis Development), dinâmica da assimilação de CO 2 , da transpiração e da condutividade estomática. O resíduo de mineração de areia puro como substrato não proporcionou mudas de qualidade, visto que esse material apresenta alta densidade e baixa granulometria. Seu uso pode ser indicado como um dos componentes de substratos, pois as plantas que cresceram nas misturas de resíduo e casca de arroz carbonizada apresentaram resultados semelhantes ao do considerado padrão. Palavras-chave: palmito; pupunha; substrato. ABSTRACTThe objective of this study was to evaluate the growth of peach palm seedlings using fine residue of sand mining as part of substrates. The experiment comprised five treatments, four containing different ratios of sand mining residue to carbonized rice husk: 1:0; 3:1; 1:1; 1:3, and one composed of alic podzolic yellow latosol and buffalo manure in a 3:1 ratio, used as the standard substrate. Treatments were arranged in randomized blocks with five replications and 10 seedlings each. One peach palm seedling was transplanted per container, which consisted of black, 8x20 cm, 1.1 L PE bags filled with different substrates. Diameter of stem, plantlet height, number of leaves and relative growth rate were recorded monthly and 180 days after their transplanting, SPAD values, dynamics of CO 2 assimilation, transpiration and stomatal conductance. The use of unmixed residue of sand mining as substrate did not produce quality seedlings, since that substance has high density and poor particle size. It can be used as part of substrates though, for plants

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