The results of the Forest Resources Assessment 2000 carried out by FAO are synthetically presented and discussed. The world forest coverage is estimated equal to 38.6 million km 2 . The comparison of the estimates from the period 1990-2000 with those from the period 1980-1990 points out a certain general deceleration of the rate of net deforestation, that currently involves around 9 million hectares every year. However, the annua1 loss of tropical forests is still very large, while temperate and borea1 forests are in expansion. Overall, FRA2000 produced a relevant effort to compensate the existing technical, institutional and financial constraints and shortcomings for monitoring the world forest resources. The need to increase the quality and the frequency of forest surveys, both at national and international levels, s t a stands as a major issue to cope with.

http://ojs.aisf.it/index.php/ifm/article/download/774/738

Valutazione delle risorse forestali a livello globale

A B S T R A C T Soil compaction influences all stages of crop growth, but in many low yield sugarcane fields critical levels and effects of soil compaction are ignored. Therefore, identifying localization and intensity of compaction are very relevant for descompactation of soil. In this context, this study aimed to apply three criteria for delineating zones for soil compaction management: soil layer where first appear values of soil penetration resistance considered critical for sugarcane growth; cone index for 0-40 cm layer, and depth of occurrence of maximum soil penetration resistance. Sampling was carried out in a grid with 113 points spaced at 100 m, georeferenced by means of a Global Positioning System receiver. Soil penetration resistance in eight layers of 5 cm depth, cone index and depth of occurrence of maximum penetration resistance were determined from data gathered by an automatic measuring penetrometer. Estimative of non-sampled values were obtained by means of kriging interpolation, which allowed drawing of contour maps and the definition of four regions in the field for site specific subsoiling . Palavras-chave: Saccharum ssp. resistencia do solo a penetracao geoestatistica penetrometro

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Revista Brasileira de Engenharia Agrícola e Ambiental

Salinity is one of the major limitations to wheat production worldwide. This study was designed to evaluate the level of genetic variation among 150 internationally derived wheat genotypes for salinity tolerance at germination, seedling and adult plant stages, with the aim of identifying new genetic resources with desirable adaptation characteristics for breeding programmes and further genetic studies. In all the growth stages, genotype and salt treatment effects were observed. Salt stress caused 33 %, 51 % and 82 % reductions in germination vigor, seedling shoot dry matter and seed grain yield, respectively. The rate of root and shoot water loss due to salt stress exhibited significant negative correlation with shoot K+, but not with shoot Na+ and shoot K+/Na+ ratio. The genotypes showed a wide spectrum of response to salt stress across the growth stages; however, four genotypes, Altay2000, 14IWWYTIR-19 and UZ-11CWA-8 (tolerant) and Bobur (sensitive), exhibited consistent responses to salinity across the three growth stages. The tolerant genotypes possessed better ability to maintain stable osmotic potential, low Na+ accumulation, higher shoot K+ concentrations, higher rates of PSII activity, maximal photochemical efficiency and lower non-photochemical quenching (NPQ), resulting in the significantly higher dry matter production observed under salt stress. The identified genotypes could be used as parents in breeding for new varieties with improved salt tolerance as well as in further genetic studies to uncover the genetic mechanisms governing salt stress response in wheat.

https://onlinelibrary.wiley.com/doi/pdf/10.1111/jac.12178

Identification and Characterization of Salt Tolerance of Wheat Germplasm Using a Multivariable Screening Approach

O manjericão (Ocimumbasilicum L.) conhecido também por basílico, alfavaca e alfava-cheirosa é uma planta da familiaLamiaceae, sendo originária da Índia e cultivada em todo o mundo. Possui propriedades medicinais, além de importância na indústria de cosméticos, perfumaria, farmacêutica e condimentos. A água é um dos fatores que limitam a produção agrícola, na qual são observadas respostas morfofisiológicas em plantas expostas a condição de déficit hídrico, sendo estas respostas a redução da taxa fotossintética, turgescência celular, processos de abertura e fechamento de estômatos, divisão e expansão celular, fornecimento de compostos orgânicos e inorgânicos para síntese de parede celular, o que afeta o crescimento e desenvolvimento dos vegetais. As bactérias do gênero Burkholderia apresentam aptidão para fixação biológica através da produção de auxinas, na qual ocorre alongamento celular resultando no crescimento vegetal. O trabalho objetivou avaliar a influência das bactérias do gênero Burkholderiasobre as características morfofisiológicas do manjericão sob condições de estresse hídrico. O experimento foi conduzido em casa de vegetação na UAG-UFRPE,em delineamento inteiramente casualizado sendo 10 tratamentos e 5 repetições. Os tratamentos consistiram na inoculação de linhagens bacterianas a G1, G2, G29 e um mix (G1+G2+G29) em sementes de manjericão. Após o desenvolvimento das plantas, as mesmas foram expostas a condições diferentes de regas (plantas irrigadas e plantas não irrigadas por cinco dias). Verificou-se que à linhagem G2 apresentou maior eficiência na germinação das sementes (80%). Em relação ao índice de clorofila, observou-se que as plantas sob estresse hídrico sem bactérias apresentaram o menor índice (29,34).O crescimento em altura foi maior nas plantas mix sem estresse hídrico (23,9 cm) e menor nas plantas G29 com estresse hídrico (14,0 cm).Foi observado que independente das bactérias o estresse hídrico reduziu significamente a massa seca da parte aérea, não foi observado diferenças significativas na massa seca das raízes. O estresse hídrico provocou redução no crescimento e desenvolvimento das plantas de Ocimiumbasilicum L. e as linhagens G1, G2, G29 e o mixnão mostraram efeitos positivos no crescimento dessas plantas.

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MORFISIOLOGIA DE MANJERICÃO EM CONDIÇÕES DE DÉFICIT HÍDRICO ASSOCIADO com BACTÉRIAS Burkholderia spp

This study aims to identify correlations between growth variables and the Dickson quality index in seedlings of Eucalyptus grandis and Pinus elliottii var. elliottii. The experiment was conducted in a greenhouse and the following variables were observed: stem base diameter, shoot height, number of leaves, leaf dry matter, stem base dry matter, root dry matter, shoot dry matter, total dry matter, ratio of shoot dry matter to root dry matter and ratio of shoot height to stem base diameter in E. grandis 60, 75, 90, 105 and 120 days after seedling emergence, and in P. elliottii 25, 50, 75, 100, 125, 150 and 175 days after seedling emergence. Using Pearson correlation and also path and regression analyses, correlations were analyzed between observed variables according to day after emergence and the Dickson quality index. Stem base diameter was found to have stronger correlation with days after emergence in comparison to shoot height, in both species. Root dry matter was found to have stronger correlation with the Dickson quality index. Stem base diameter was the most suitable parameter to indicate seedling quality due to its higher correlation level with the Dickson quality index. Shoot height was only effective to indicate seedling quality if analyzed together with stem base diameter. Variables relating to dry matter showed the highest correlations with the Dickson quality index (DQI), followed by stem base diameter. Conversely, number of leaves showed the poorest correlations with DQI, followed by seedling height.

/pdf/correlations-between-growth-variables-and-the-dickson-qgo60ngh0x.pdf

Correlations between growth variables and the Dickson quality index in forest seedlings

This work aimed to verify the influence of the under shading period in the parameters employed to evaluate Trema micrantha (crindiuva) seedling quality pattern. The research was carried out using a randomized design, with four replications per treatment and 88 plants per replication. Three evaluations were performed at 90, 120 and 150 days after emergence. The following treatments were used in the evaluation: Evaluation I, 45, 60, 75 and 90; Evaluation II, 45, 60, 75, 90, 105 and 120 and Evaluation III, 45, 60, 75, 90, 105, 120, 135 and 150 days under shading with 48% of solar radiation retention, respectively. The morphological parameters of the seedlings, their relationships, and the Dickson quality index were evaluated. Seedlings developed under the longer shading periods presented higher shoot heights and leaf area but the lowest values for seedling quality, such as smaller stem diameter, root dry mass and the Dickson quality index. They also presented an increase in shoot height/stem diameter and shoot/root ratios. Period under shading did not affect significantly the parameters for leaf area, leaf dry mass, shoot and total. Seedlings showed better quality patterns at 120 days, when grown under 45 and 60 days under shading. The Dickson's quality index was the best and the most suitable parameter to evaluate the target seedling grown in a suspended nursery.

https://www.scielo.br/pdf/rarv/v26n4/a15v26n4.pdf

Padrão de qualidade de mudas de Trema micrantha (L.) Blume, produzidas sob diferentes períodos de sombreamento

O angico-de-bezerro (Piptadenia moniliformis Benth.) e uma especie arborea melifera, de crescimento rapido, caracteristica da caatinga do nordeste brasileiro, onde e muito abundante e com dispersao contigua e irregular. Seus ramos finos, junto com as folhas, servem como alimento para animais. Como suas sementes apresentam dormencia por impermeabilidade do tegumento a agua, objetivou-se neste trabalho avaliar a eficiencia de tratamentos pre-germinativos para superar a dormencia de suas sementes visando maximizar e uniformizar o processo de germinacao. Foram estudados 28 tratamentos pre-germinativos: imersao em agua a 70, 80, 90 oC e fervente por 1, 2, 3, 4 e 5 minutos e imersao em acido sulfurico concentrado por 1, 5, 10, 15, 20, 25 e 30 minutos, alem da testemunha. A semeadura foi realizada sobre papel em temperatura alternada de 20-30 oC, utilizando-se quatro repeticoes de 25 sementes. Foram avaliadas as porcentagens de germinacao das sementes considerando a protrusao da raiz primaria, de plântulas normais e de sementes duras e o indice de velocidade de germinacao. O delineamento experimental utilizado foi o inteiramente casualizado e as medias comparadas pelo teste de Scott-Knott a 5% de probabilidade. Os tratamentos de imersao em agua, independentemente da temperatura e do periodo de imersao, aumentaram a porcentagem de germinacao das sementes, comparativamente ao tratamento controle, mas foram menos eficientes que os tratamentos em acido sulfurico nos maiores periodos de imersao. Desta forma, a imersao por 20, 25 e 30 minutos em acido sulfurico e recomendada para a superacao da dormencia de sementes de Piptadenia moniliformis Benth.

/pdf/superacao-de-dormencia-de-sementes-de-piptadenia-2981p1n2mt.pdf

Superação de dormência de sementes de Piptadenia moniliformis Benth

In information regarding the "Bioma Cerrado" becomes more urgent due to its accelerated destruction. This work conducted a floristic inventory and an analysis of phytosociological parameters in an area of cerrado "stricto sensu" at Santa Cecilia's farm, in Sao Paulo State (20o46'12"S e 47o14'24"W, 836m of altitude and Neosoil Quartzarenic). Thirty plots of 10 x 10 m were established in which 511 arborous individuals with GBH >15cm were registered and belong to 30 families and 53 species. The families with the highest numbers of species were: Fabaceae (7 species), Myrtaceae (5), Vochysiaceae (4), Annonaceae (3) and Caesalpiniaceae (3), and these represented about 45% of total species. The species with the highest importance value (IV) were: Qualea grandiflora (62,38), Dalbergia miscolobium (22,24), Styrax camporum (21,86), Ocotea corymbosa (18,02), Qualea parviflora (14,97) and Qualea multiflora (11,46). Density was 1.703 ind/ha, Diversity Shannon's index of (H') 3,05 and Similarity Jaccard's index (ISj) was 45% when compared to a close cerrado area.

/pdf/floristica-e-fitossociologia-de-area-de-cerrado-s-s-no-47bndh24ec.pdf

Florística e fitossociologia de área de Cerrado s.s. no Município de Patrocínio Paulista, nordeste do Estado de São Paulo

Agronomia Pela Faculdade de Ciencias Agrarias e Veterinarias Universidade Estadual Paulista, Rua Emilio Menon, 268, Taquaritinga, SP - 15900-000

Eficiência de uso de boro no crescimento de clones de eucalipto em vasos

The objective of this study was to evaluate qualitative and quantitatively the seed bank of two natural forest remainders, one Eucalyptus robusta plantation and three reforestation areas with native species, located in a riparian area of Mogi-Guacu River floodplain, in Luiz Antonio County (21°31´S and 47°55´W), Sao Paulo State, Brazil The evaluation was carried out in 12 plots of 10 x 10 m systematically distributed in each area Four subplots of 05 m x 05 m were randomly distributed in each plot Two subplots were used to evaluate the seed bank in the litter and two in the soil sample at the 0 - 5 cm depth The sampling was accomplished in September 2001 in the natural forest remainders and in the eucalyptus plantation and, in September 2002, in the reforested areas The soil and the litter were conditioned in plastic pots, and incubated with periodic irrigations for the seed germination during seven months, in two greenhouse environment conditions: one at 100% sunlight and the other, under a screen that provides a 70% sunlight reduction In the composition of all sample area seed banks, there was a predomination of pioneer species at the early successional stages The most important arboreal species were Aloysia virgata and Cecropia hololeuca The reforestation with native species provided a seed bank with a greater diversity of native arboreal species than the eucalyptus plantation The present study indicates that the similarity between the planted and natural forest should be enhanced over the time

/pdf/banco-de-sementes-de-remanescentes-naturais-e-de-areas-23bronrn99.pdf

Sérgio Valiengo Valeri

Papers

Padrão de qualidade de mudas de Trema micrantha (L.) Blume, produzidas sob diferentes períodos de sombreamento

Superação de dormência de sementes de Piptadenia moniliformis Benth

Florística e fitossociologia de área de Cerrado s.s. no Município de Patrocínio Paulista, nordeste do Estado de São Paulo

Eficiência de uso de boro no crescimento de clones de eucalipto em vasos

Banco de sementes de remanescentes naturais e de áreas reflorestadas em uma várzea do Rio Mogi-Guaçu - SP