Good Quality Seedlings Research Articles

Efeito de diferentes substratos na produção de mudas de mangabeira (Hancornia speciosa)

A mangabeira (Hancornia speciosa Gomes) é uma espécie frutífera nativa do Cerrado, que devido às características dos seus frutos apresenta enorme potencial de aceitação pelo mercado consumidor, além de apresentar expressivo potencial produtivo. Objetivou-se avaliar o efeito de diferentes substratos na produção de mudas de mangabeira em sacos de polietileno e determinar o melhor substrato para a propagação da espécie. O trabalho foi conduzido em casa de vegetação na Universidade Estadual de Mato Grosso do Sul, Unidade Universitária de Cassilândia. O delineamento experimental foi em blocos casualizados, com quatro repetições e 15 plantas por parcela. Foram testadas cinco misturas de substratos: A (areia lavada + Plantmax® + solo, 1:1:3 v:v:v); B (casca de arroz carbonizada + Plantmax® + solo, 1:1:3); C (casca de arroz carbonizada + húmus de minhoca + solo, 1:1:3); D (esterco bovino + Plantmax® + solo, 1:1:3), e E (esterco bovino + solo, 2:3). Foram avaliados os parâmetros: porcentagem de germinação, índice de velocidade de emergência (IVE), porcentagem de mortalidade, altura da muda (cm), diâmetro do colo (mm), comprimento da raiz (cm), número de folhas/planta, índice de clorofila foliar (CCI), massa seca, parte aérea da raiz e total (g/planta). As melhores características para uma muda sadia e de boa qualidade para pegamento no campo foram obtidas com os substratos D e E, sendo estes os recomendados para a produção de mudas de mangabeira em sacos de polietileno.

Desenvolvimento e qualidade nutricional de mudas de mangabeiras cultivadas em substratos contendo fibra de coco e adubação fosfatada

Para a produção de mudas de qualidade, é necessária a utilização de substratos com propriedades físicas, químicas e biológicas que condicionem a germinação adequada das sementes e o estabelecimento das mudas. Neste sentido, foi realizado um experimento no Centro de Ciências Agrárias, da Universidade Federal da Paraíba, com o objetivo de avaliar o crescimento e a composição mineral de mudas de mangabeiras (Hancornia speciosa) em substratos compostos por diferentes proporções de fibra de coco (0% a 40%), esterco bovino (0% a 25%), terra vegetal (25% a 70%) e 15% de areia, fertilizados com superfosfato triplo (0; 5,5 e 11 g dm-3). A terra vegetal e a fibra de coco exerceram efeitos benéficos às mudas com o aumento de suas proporções no substrato. A adição do esterco e do superfosfato triplo inibiu a produção de matéria seca e a área foliar das mudas. Houve aumento dos teores de nutrientes nas mudas com o aumento da concentração de esterco nos substratos. Pela estimativa dos resultados, o substrato que proporciona maior crescimento e composição mineral mais equilibrada nas mudas de mangabeira deve ser constituído por 14% de esterco, 56% de terra vegetal, 15% de fibra de coco, 15% de areia e 4 g dm-3 de superfosfato triplo.

Métodos de avaliação da ferrugem do álamo e eficiência de fungicidas no seu controle

A ferrugem do álamo (Melampsora medusae Thuem.) causa sérios prejuízos no viveiro, e seu controle é fundamental para a obtenção de muda de boa qualidade. Este trabalho teve como objetivos: i) testar a eficiência de fungicidas de contato (mancozebe, cartap e oxicloreto de cobre) e sistêmicos (triadimenol, tebuconazole e difenoconazole) no controle da ferrugem; ii) comparar métodos de avaliação para discriminar a eficiência entre os tratamentos; iii) relacionar desfolha com dados de doença; e iv) verificar a influência do controle da ferrugem nos parâmetros de crescimento da árvore em viveiro. O experimento foi montado em São Mateus do Sul, PR, delineado inteiramente ao acaso com 10 tratamentos (testemunha, triadimenol, mancozebe, tebuconazole, difenoconazole, cartap, oxicloreto de cobre, triadimenol-mancozebe, tebuconazole-mancozebe e triadimenol aplicados com o dobro do intervalo dos anteriores) e 11 repetições. Com parcelas experimentais de 10 m de largura com quatro linhas de plantio (espaçamento entre linhas de 2,5 e entre plantas de 0,50 m), totalizando 110 parcelas com o clone Latorre. Durante dois ciclos consecutivos foram avaliados: o número de pústulas em meia folha, a % visual de doença, a severidade por parcela, a % visual de desfolha, o diâmetro à altura do peito e a altura de plantas ao final do experimento. Os produtos sistêmicos (triadimenol, tebuconazole e difenoconazole) aplicados puros ou intercalados com mancozebe foram eficientes no controle da ferrugem, reduzindo o número de pústulas sobre a folha e a desfolha, o que resultou em ganho significativo no volume final das plantas. O mancozebe aplicado isoladamente também reduziu a epidemia e aumentou o volume da árvore em 42%. O produto cúprico proporcionou aumento de volume em 27%. Os métodos de avaliação utilizados diferenciaram dos tratamentos e houve correlação da doença com os danos na cultura.

Effect of sowing dates on the germination and seedling growth of Pinus wallichiana and Cupressus torulosa

A nursery trial of Pinus wallichiana and Cupressus torulosa with nine different sowing dates spread over autumn, winter and spring was conducted during 2002-2003. Germination in case of Pinus wallichiana was better where seeds were sown in the month of February, but in Cupressus torulosa germination during December, February and first fortnight of March was uniform. Survival percentage of seedlings was more in seeds sown in the month of February. Time taken for completion of germination decreased as sowing proceeded from autumn to spring. Seedling development in terms of height and diameter was better in seeds sown on 15th of November (autumn), but seedlings obtained from 1st February sown seeds are also of comparable good quality. The study concluded that in order to get good germination, better survival, good quality seedlings and cost effective nursery seeds should be sown in the nursery in the first fortnight of February (winter), instead of sowing in autumn season as is normally practiced.

Características físicas e químicas de substratos para produção de mudas de Ilex paraguariensis St. Hil.

Neste trabalho, objetivou-se avaliar as propriedades físicas e químicas de diferentes materiais e suas combinações, bem como sua influência na produção de mudas de erva-mate em tubetes plásticos. O trabalho foi conduzido no viveiro da Empresa Baldo S.A., em São Mateus do Sul, PR. Utilizaram-se seis materiais: esterco bovino curtido, serragem semidecomposta, palito de erva-mate picado, terra de subsolo, substrato comercial à base de casca de pinus e húmus de minhoca, com os quais foram formulados 14 tratamentos. Os resultados indicaram que os tratamentos que continham serragem, palito de erva-mate e, principalmente, esterco bovino, além de serem mais econômicos, mostraram bons resultados na qualidade das mudas produzidas. Dentre esses tratamentos, aquele composto de 40% de esterco bovino e 60% de serragem se destacou, em vista da boa relação custo-benefício apresentada e da sua facilidade de preparo. As características químicas dos substratos não interferiram nas suas características físicas, assim como a influência das características físicas na produção de mudas de erva-mate depende da variável analisada.

A Novel Method of Supplying Nutrients Permits Predictable Shoot Growth and Root : Shoot Ratios of Pre-transplant Bedding Plants

Growth of bedding plants, in small peat plugs, relies on nutrients in the irrigation solution. The object of the study was to find a way of modifying the nutrient supply so that good-quality seedlings can be grown rapidly and yet have the high root : shoot ratios essential for efficient transplanting. A new procedure was devised in which the concentrations of nutrients in the irrigation solution were modified during growth according to changing plant demand, instead of maintaining the same concentrations throughout growth. The new procedure depends on published algorithms for the dependence of growth rate and optimal plant nutrient concentrations on shoot dry weight W(s) (g m(-2)), and on measuring evapotranspiration rates and shoot dry weights at weekly intervals. Pansy, Viola tricola 'Universal plus yellow' and petunia, Petunia hybrida 'Multiflora light salmon vein' were grown in four independent experiments with the expected optimum nutrient concentration and fractions of the optimum. Root and shoot weights were measured during growth. For each level of nutrient supply W(s) increased with time (t) in days, according to the equation DeltaW(s)/Deltat=K(2)W(s)/(100+W(s)) in which the growth rate coefficient (K(2)) remained approximately constant throughout growth. The value of K(2) for the optimum treatment was defined by incoming radiation and temperature. The value of K(2) for each sub-optimum treatment relative to that for the optimum treatment was logarithmically related to the sub-optimal nutrient supply. Provided the aerial environment was optimal, R(sb)/R(o) approximately W(o)/W(sb) where R is the root : shoot ratio, W is the shoot dry weight, and sb and o indicate sub-optimum and optimum nutrient supplies, respectively. Sub-optimal nutrient concentrations also depressed shoot growth without appreciably affecting root growth when the aerial environment was non-limiting. The new procedure can predict the effects of nutrient supply, incoming radiation and temperature on the time course of shoot growth and the root : shoot ratio for a range of growing conditions.

Pricing the risk of the quality-guarantee in a stand establishment service

A stand-establishment service concept with quality guarantee was analysed. Here, the quality of stand establishment was assessed as the density of good quality seedlings evenly distributed on the plantation three years after planting. The amount of adequate premiums for the guarantee service and the risks accumulating to the service provider were studied. Monte Carlo simulation was used as a tool for analyzing the risks accumulating to the service provider of the stand-establishment in operational environments of different sizes. The premiums calculated to cover the expected amount of claims caused by the plantations not meeting the pre-set criteria were about 4–8% in addition to the approximated costs of stand establishment. The criteria used for determining the success or failure in a stand have a marked effect on the amount of premiums with a reasonable risk of ruin.

Refinement of potting medium ingredients for production of high quality seedlings of sandalwood (Santalum album L.)

Summary This study was undertaken in order to refine the potting medium and improve seedling growth of Santalum album L. in root trainers. The potting medium ingredients, including sand, soil, compost, cocopeat, burnt rice husk and charcoal, were tested in fourteen combinations in 270 mL block-type root trainers using Cajanus cajan as a pot host. A medium consisting of sand, soil, compost, burnt rice husk (BRH) and charcoal in the ratio of 25:15:50:5:5 favoured overall seedling growth in terms of height, collar diameter, shoot dry weight, root dry weight, total dry weight, root fibrosity and quality index at age 6 mo. The next best medium was a mixture of sand, soil and compost in the ratio 35:15:50. Where rice husk and charcoal are not available, this second medium may be used to produce good quality seedlings. The best potting medium for sandalwood had up to 60% organic matter mixed with sand and soil. This medium had low bulk density, good aeration and water-holding capacity, encouraged lateral root formation, and ensured good plug formation and easy plug removal. A high proportion of sand, soil or organic matter caused poor seedling growth.

Effect of container type and size on the growth and quality of seedlings of Indian sandalwood (Santalum album L.)

Summary Studies were carried out to determine the effects of container type and size on the growth and quality of seedlings of Indian sandalwood (Santalum album L.), an over-exploited hemi-root parasite. Three types of container, viz. root trainers (150,270,300, 450 and 600 mL), polythene bags (polybags) (600, 1000 and 1500 mL) and plastic containers (1000 mL) were used with a potting medium that consisted of sand, soil, compost, burnt rice husk and charcoal in the ratio of 5:3:10:1:1. Cajanus cajan was used as a primary host in all treatments. Survival and overall growth of sandalwood seedlings 6 mo old, in terms of height, collar diameter, seedling biomass and root-shoot ratio, were best in root trainers, and next best in plastic containers. Among the root trainers, the 600 mL size was optimum for most of the parameters of seedling quality, including height (20.4 cm), total dry weight (3.06 g), shoot dry weight (1.66 g), root dry weight (1.41 g) and quality index (0.37). This size was followed by the 270 and 300 mL root trainers. Despite the large size of the polybags (600–1500 mL), seedling growth in these was poor. Root coiling and poor root development affected root dry weight (0.13–0.39 g) and the quality index (0.03–0.05). Good quality seedlings >20 cm high, >3.0 mm in collar diameter and with an 0.3 quality index can be produced in 6 mo in 600 mL root trainers. Most of the parameters of seedling quality (seedling height, collar diameter, seedling biomass and quality index) of seedlings grown in 270 mL block-type root trainers were comparable with those of seedlings in 1000 mL plastic containers. This result encourages further reduction in container size from 600 mL to 270 mL by better managing nutrition and screening for better primary hosts.

Produção de mudas de espécies arbóreas nativas com combinações de adubos de liberação controlada e prontamente solúveis

O objetivo deste estudo foi testar diversas doses e fontes de adubo para verificar o crescimento de mudas de cinco espécies arbóreas nativas. As espécies utilizadas foram as pioneiras Guazuma ulmifolia (mutambo) e Croton floribundus (capixingui), as secundárias iniciais Peltophorum dubium (canafístula) e Gallesia integrifolia (pau-d'alho) e a clímax Myroxylon peruiferum (cabreúva). Os tratamentos consistiram principalmente na utilização de adubo de liberação controlada (ALC, 19-06-10, N-P2O5-K2O) de maneira pura ou em mistura com adubo em pó (AP, 14-16-18), ou AP mais adubação de cobertura periódica (ACP, 19-06-20), comparados com adubação convencional (adubação de base mais adubação de cobertura com sulfato de amônio e cloreto de potássio) e testemunha (sem adubação). O substrato utilizado foi composto por 60% de húmus de minhoca, 30% de casca de arroz carbonizada e 10% de terra de subsolo, em base volumétrica. O recipiente que comportou o substrato foi o tubete de polipropileno de 50 cm³ de capacidade. Entre os tratamentos que produziram mudas de boa qualidade ao final do experimento, para cada espécie, aqueles com doses de 3,2 e 4,8 kg de adubo de liberação controlada por metro cúbico de substrato foram comuns a todas as espécies e, adicionalmente, resultaram em dimensões apropriadas para plantio no campo em menor tempo do que os outros tratamentos.

Response of Jatropha seedlings to seed size and growing medium

An experiment was conducted at HAU Regional Research Station, Bawal in order to get good quality seedlings for planting; on investigating the effect of seed size and rooting media on the growth of Jatropha curcas seedlings. Seedlings from large sized seeds showed significant increase in height, collar diameter, root length, number of leaves and dry matter production than small sized seeds. Rooting medium containing farmyard manure (FYM) was significantly better than rooting medium without farmyard manure.

Influence of seed size grading and seed testing media on expression of seed quality in Parkia biglobosa

Studies were made in Parkia biglobosa to standardise testing media for lab germination and also to evaluate the association of seed quality with seed size. The study revealed that in sand media the germinability of the seed was fully expressed compared to paper media. Seed quality in terms of germination and vigour were in close association with size, wherein the bigger seeds produced elite seedling and the smaller one, the seedlings of poor stamina. For obtaining good quality seedlings, seeds can be graded using 17/64" round perforated metal sieves of American sieve system (AST) and the retained seeds can be used for sowing.

Afforestation of marginal agricultural land in the Lower Mississippi River Alluvial Valley, U.S.A.

Afforestation of marginal agricultural land in the Lower Mississippi Alluvial Valley (LMAV) relies on native species, planted mostly in single-species plantations. Hard mast species such as oak and pecan are favored for their value to wildlife, especially on public land. Successful afforestation requires an understanding of site variation within floodplains and matching species preferences and tolerances to site characteristics, in particular to inundation regimes. Soil physical conditions, root aeration, nutrient availability, and moisture availability during the growing season also must be considered in matching species to site. Afforestation methods include planting seedlings or cuttings, and direct-seeding. Both methods can be done by hand or by machine. If good quality seedlings are planted properly and well cared for before planting, the chances for successful establishment are high but complete failures do occur. Mortality and poor growth are caused by many factors: extended post-planting drought or flooding; poor planting or seeding practices; poor quality seed or seedlings; animal depredation; or herbicide drift from aerial application to nearby cropland. More species can be planted, even on continuously flooded sites. Direct-seeding, while limited to heavy-seeded species (oaks and hickories), costs less than 50% of planting seedlings. Growth varies considerably by soil type; most bottomland hardwoods grow best on silt loam and less well on clay soils. Up to 200Â 000 ha of land in the LMAV subject to spring and early summer backwater flooding could be afforested over the next decade.

Problems and Future of Transplant Production in East Asia-Taiwan Case.

There are more than 75, 000 ha of cruciferous, solanaceous and curcurbitaceous crops that are using transplants in production and a total amount of over 1.2 billion transplants are needed each year in Taiwan. Providing good quality seedlings to farmers is important for successful crop production. After the introduction of using plug trays for growing seedling in early 1980, it has been widely adopted by growers. Due to its advantage, many farmers prefer to purchase plug transplants rather than grow their own. More than 30 nursery centers providing transplants to farmers have been established in Taiwan. In the past 15 years, public and private sectors have conducted much research work concerning plug culture practice, which is the leading factor for successful development of plug growing in Taiwan.

An Improved Embryo-Rescue Protocol for a Carica Interspecific Hybrid

An improved embryo-rescue protocol was developed for embryos (90 days old) of Carica papaya L. (Clone 2001), and subsequently was utilised for efficient production of interspecific hybrids of C. papaya × C. cauliflora Jacq. from 90- to 120-day-old embryos. Pre-incubation of C. papaya embryos for 7 days on a germination medium containing half-strength De Fossard nutrients supplemented with gibberellic acid (10 μM), 6-benzylamino-purine (0.25 μM), alpha-naphthalene-acetic acid (0.25 μM). sucrose (58 mM) and agar (8 g L-1) supported 100% germination. Subsequent transfer of germinated embryos to a nutrient medium that was identical, except that it was free of plant growth regulator, allowed good growth but induced shoot etiolation and callus production. Reducing the pre-incubation of C. papaya embryos on this medium to 5 days before transfer to the medium free of plant growth regulator produced similarly high germination (96%), but allowed for the production of good quality seedlings that were unetiolated and free of unwanted callus. For interspecific hybrids, a 5-day pre-incubation of the embryos on a liquid formulation was better than the solid formulation as it promoted better growth and vigour of the normally abortive interspecific hybrid embryos. Using the improved protocol, 1981 of 2100 (94%) interspecific hybrid embryos consisting of single and multiple forms were germinated. In all cases, the germinating multiple embryos underwent further embryogenesis that allowed for the production of 485 (25%) morphologically normal hybrid plants grown in soil in the glasshouse.