Soil salinity is a major abiotic factor limiting crop production but an amendment with compost, zeolite or unisal may mitigate the effects of salinity stress on plants. The objective of the present study was to determine the effects of compost, zeolite and unisal on growth of barley plant irrigated with diluted seawater. Barley was the grown on a calcareaus soil treated with compst, zeolite and unisal at the rates of 0 , 4, 8 and 12 % and irrigated with seawater diluted to electrical conductivity (EC) levels of 2.5, 5.0 and 7.5 dS m-1 while tap water was as the control (EC = 0.44 dS/m. Irrigation with 5.0 and 7.5 dS m-1 saline waters significantly suppressed fresh and dry weight of barely plants. However, a substantial increase in plant biomass of salt stressed barley was observed with the three amendments followed the order, compost > unisal > unisal. The application of compost, zeolite or unisal also enhanced K + , Ca +2 and Mg +2 absorption and decreased Na + , Cl-and SO4 = in barely shoot. Post-harvest soil analysis showed high EC values of soil due to saline water irrigation but concentrations were lower in soils treated with the tested amendments especially zeolite. The overall results indicated that soil amendment with compost or zeolite could effectively ameliorate salinity stress and improve nutrient balance barley plant grown on a calcareous soil.

The objective of this study was to analyze the effect of water deficit stress on the growth of Dipteryx alata plants. The experiment was carried out on a bench in full sun at the Goiás State University experimental unit, in Ipameri town, Goiás. Dipteryx alata seeds were collected from native plants in that municipality and sown in four-liter pots containing a mixture of soil, sand and cattle manure at ratio 3:1:0.5, respectively. The experiment was set up following the completely randomized design with five treatments (plants irrigated for 25 days with water volumes corresponding to 0%, 25%, 50%, 75%, and 100% of daily evapotranspiration) and six replicates. Treatments were applied when the plants were 60 days old, and at 85 days the plants were assessed for the following parameters: plant height, stem diameter, number of leaves, foliar chlorophyll concentration (a+b ), total carotenoids, relative water content, transpiration, leaf, stem and root mass ratios, and total biomass. During early development, the Dipteryx alata plants were highly sensitive to water deficit, significantly slowing down vegetative growth. Accordingly, in order to remain alive, the plants drastically reduced transpiration as a result of high stomatal sensitivity.

O presente estudo teve como objetivo identificar a(s) estratégia(s) de sobrevivência de plantas de Tectona grandis sob déficit hídrico para fomentar programas de melhoramento genético. O trabalho foi conduzido em casa de vegetação coberta com plástico transparente e laterais fechadas com sombrite 50%. As sementes de Tectona grandis foram semeadas em vasos de 12 litros contendo uma mistura de solo, areia e esterco na proporção de 3:1:0,5 respectivamente. Utilizou-se o delineamento experimental inteiramente casualizado com cinco tratamentos e seis repetições. A partir do 101º dia após a germinação, as plantas foram submetidas a regimes hídricos diferenciais: plantas diariamente irrigadas com volume de água correspondente a 0%, 25%, 50%, 75% e 100% da evapotranspiração diária durante 20 dias e, em seguida, submetidas as análises. Em condição de déficit hídrico as plantas de Tectona grandis mantêm-se vivas com reduzido crescimento vegetativo, para tal, as plantas ajustam a área foliar e apresentam como estratégia de sobrevivência um eficiente mecanismo de fechamento estomático em função da elevada sensibilidade dos estômatos. O controle estomático da transpiração pode ser utilizado para pré-seleção de materiais promissores para programas de melhoramento genético.

The development of technologies will certainly contribute to boost the commercial exploitation and domestication of Spondias tuberosa. The objective of the present study was to identify morphophysiological effects of gibberellin on the growth of S. tuberosa seedlings. The experiment was conducted in a greenhouse at the Goiás State University, Brazil, using 300-day-old S. tuberosa seedlings planted in 12-liter pots containing soil (Typic Hapludox), sand, and manure (3:1:0.5). The experiment was conducted in a completely randomized design, with five replications and six treatments consisting of single foliar applications of 30 mL plant-1 of solutions with different gibberellin (GA3) concentrations (0, 150, 300, 450, 600, and 750 mg L-1), using a manual sprayer. The plants were evaluated at 60 days after the applications. The maximum biomass accumulation in S. tuberosa seedlings was found with the use of 415 mg L-1 of GA3. The use of gibberellin accelerated the vegetative growth of S. tuberosa plants and enabled the formation of seedlings with better root system and xylopodium, and aerial parts with greater number of leaves, leaf area, and stem weight.

A utilização de fitohormônios em espécies nativas, especificamente umbuzeiro, é escassa, no entanto, o uso de reguladores de crescimento pode tornar-se uma prática inovadora de manejo da espécie ao interferir decisivamente na precocidade. O presente estudo teve como objetivo identificar o efeito do ácido giberélico no crescimento de mudas de umbuzeiro (Spondias tuberosa Arruda). O trabalho foi conduzido sob bancada em casa de vegetação coberta com plástico transparente e laterais com sombrite que interceptam 50% da radiação solar na Universidade Estadual de Goiás. O experimento foi conduzido seguindo o delineamento inteiramente casualizado com cinco tratamentos (plantas de Spondias tuberosa com 250 dias de idade foram tratadas com solução de 30 ml de ácido giberélico (GA3) por planta, nas concentrações de 0 mg L-1; 100 mg L-1; 200 mg L-1; 300 mg L-1 e 400 mg L-1; em aplicação única via foliar com auxílio de borrifador manual), seis repetições e parcela de uma planta útil por vaso. A giberelina intensificou o crescimento vegetativo de mudas de umbuzeiro e proporcionou a formação de plantas com sistema radicular vigoroso, caule espesso e comprido e área foliar abundante e exuberante com máxima biomassa obtida na concentração de 337 mg L-1 de GA3. A aplicação de giberelina pode constituir importante prática de manejo de plantas de umbuzeiro no sentido de obter plantas precoces com menor tempo de fase juvenil e, com isso, antecipar o período produtivo, no entanto, trabalhos posteriores a nível de campo são necessários para validação e recomendação.

The objective of the present study was to evaluate the effect of the irrigation water salinity on the initial growth of Tectona grandis plants. The work was carried out in a greenhouse with 100% solar radiation interception at Goiás State University, Ipameri Campus, Brazil. The Tectona grandis seeds were sown in eight-liter pots containing a mixture of soil, sand and manure at ratio 3:1:0.5, respectively. At 100 days after germination, the plants were irrigated daily with water of different electrical conductivity (0, 2, 4, 6, and 8 dS m -1 ) for 30 days and then subjected to analysis Tectona grandis to stay alive and reduced water loss by transpiration through efficient stomatal control. Tectona grandis plants in the early stages of development are highly sensitive to salinity stress, significantly slowing down vegetative growth.

The objective of the present work was to evaluate the effect of plant growth regulators (PGR) on the vegetative development and productivity of Jatropha curcas plants. A field experiment was conducted at the Goiás State University, Brazil, using two-year-old J. curcas plants planted with spacing of 3 × 2 m, using foliar applications of two PGR—trinexapac-ethyl and prohexadione-Ca. A randomized block design was used with four treatments (trinexapac-ethyl at 1 ml plant-1—T1; prohexadione-Ca at 2 mg plant-1—T2; trinexapac-ethyl at 1 ml plant-1 plus prohexadione-Ca at 2 mg plant-1—T3; and Control—T4), five replications, and plots consisting of two plants. Two applications of a 300 ml plant-1 solution with the treatments were performed with a 30-day interval after the leaf emergence period (late September and October 2017). The trinexapac-ethyl and prohexadione-Ca plant growth regulators increased the grain yield of Jatropha curcas plants by increasing their vegetative growth, and number of inflorescences, and female and hermaphrodite flowers, but had no effect on the uniformity of fruit maturation. The treatment in which both plant growth regulators were used presented the best results, generating more vigorous and productive plants.

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