Effect of drought on ericoid mycorrhizae in wild blueberry (Vaccinium angustifolium Ait.)

2003 ◽  
Vol 83 (3) ◽  
pp. 583-586 ◽  
Author(s):  
E. Jeliazkova and D. Percival

To evaluate the influence of water exclusion on the mycorrhizal coloni zations in wild blueberry, and to examine the spatial distribution of mycorrhizae among roots of wild blueberry plants that were in both the vegetative and cropping stages of production, a randomized complete block design was used. The mycorrhizal coloniz a tions were equally distributed throughout upper and lower soil profiles in both stages of production. Nevertheless, soil moisture levels in water exclusion treatments were as much as 50% lower than the control, drought stress had no effect on mycorrhizal colonization levels or on any other of the measured responses. Root weight and volume decreased as soil depth increased from 0-7.5 to 7.5-15 cm. Key words:

HortScience ◽  
1990 ◽  
Vol 25 (8) ◽  
pp. 852c-852 ◽  
Author(s):  
D.L. Creech ◽  
C. Martindale ◽  
R. Rankin

Brightwell and Climax plants were established in March, 1987, under the following above-ground treatments: 1) polyfabric weed barrier, 2) a 6 cm deep, 1-meter wide strip of continuous bark, and 3) zero. Below-ground treatments included, 1) 19 liters peatmoss, 2) 19 liters pine bark, 3) a continuous bark strip, tilled in, and 4) zero. A randomized complete block design was utilized with above-ground treatments as main plots and in-ground. treatments as split plots. After three years, plants under polyfabric had higher above-ground dry weights, growth indexes, plant height, root dry weights and root lengths than plants under continuous bark or zero. In the deep, coarse, easily-leached sand, all roots were very shallow (0-20cms) and concentrated along the drip line and in organic matter fractions. There were no significant differences between in-ground treatments.


2020 ◽  
Vol 33 (2) ◽  
pp. 287-298
Author(s):  
AMANDA DOS SANTOS SOUZA ◽  
JÉSSICA FERREIRA LOURENÇO LEAL ◽  
ANA CLAUDIA LANGARO ◽  
GLEDSON SOARES DE CARVALHO ◽  
CAMILA FERREIRA DE PINHO

ABSTRACT Soil moisture can alter the transport and permanence of pre-emergent herbicides. The objective of this work was to evaluate the influence of water availability in the soil on the leaching of a commercial mixture of the herbicides imazapyr + imazapic, as well as the carryover effect of this herbicide in corn planted in succession to soybean. The experiment was carried out in leaching columns in a randomized block design with 4 replications. A 3x3x2 factorial scheme was used, with factor A being the irrigation (130%, 100% and 70% of field capacity (CC)), factor B the doses of the commercial mixture of the herbicides imazapyr + imazapic (0.00+ 0.00; 52.5 + 17.5 and 105 + 35 g ha-1) and factor C at soil depth (0-0.3 m and 0.3-0.6 m). Soybean sowing was performed at the top of the columns and immediately after herbicide mixture was applied. After 120 days the columns were opened, generating two sections, where corn (Zea mays) and the other watermelon (Citrullus lanatus) were sown as a bioindicator of herbicide residue. The fluorescence parameters of chlorophyll a at 15 and 30 days after germination (DAG) and shoot dry matter accumulation at 30 DAG were evaluated. There was greater retention of the herbicide imazapyr + imazapic at a depth of 0-0.3m at 70% CC condition and leaching at a depth of 0.3-0.6m at 130% CC condition, with a reduction in the mass accumulation of watermelon plants. The herbicide has a carryover potential for corn cultivation in soils maintained at 70% CC.


2019 ◽  
Vol 37 (2) ◽  
pp. 153-165
Author(s):  
Julio Jaramillo ◽  
Marlon Vintimilla ◽  
David Rubio ◽  
Gonzalo Soto ◽  
Mauricio Tobar ◽  
...  

The effects of nematicide rotation on banana (Musa AAA cv. Williams) root weight, root nematode control, and crop yield were compared in a commercial banana plantation in Ecuador, testing six treatments in a randomized complete block design with six replicates. Treatments consisted of two, three and four different nematicide cycles per year plus the untreated control. Regarding the untreated plants and averaging the 24 root nematode samplings after treatment application, the nematicide applications reduced significantly R. similis (P<0.0001) between 20 and 49%, Helicotylenchus spp. (P<0.0001) between 31 and 51%, and total nematode populations (P<0.0001) between 29 and 49%. Accordingly, in the treated plants, there was an increase between 16 and 21% in living root weight (P=0.0003), and its percentage (P<0.0001) reached between 74.5 and 81.7% in the follower suckers. In addition, the death of roots by nematodes decreased (P=0.0009) between 20 and 46%. At harvest, nematicide applications increased bunch weight (P=0.0002; P=0.0467), ratio (P=0.0003 at 12 months), ratooning (P<0.0001; P<0.0001) and the number of boxes of 18.14 kg (P<0.0001; P=0.0005) per hectare per year at 12 and 24 months after treatment application, respectively. Plants treated with nematicides increased yield between 671 and 1,158 (12.2 - 21 t) and the number of boxes of 18.14 kg per hectare per year also increased between 545 and 1,046 (9.9 - 19.0 t), which resulted in a net profit between US $3,266 - $5,750 and between US $2,587 and $5,144 per hectare per year at 12 and 24 months after treatment application, respectively.


2020 ◽  
Vol 30 (6) ◽  
pp. 670-676
Author(s):  
Scott Neil White ◽  
Linshan Zhang

Hair fescue (Festuca filiformis) is a tuft-forming perennial grass that reduces yields in lowbush blueberry (Vaccinium angustifolium) fields. Nonbearing year foramsulfuron applications suppress hair fescue, but there is interest in increasing suppression through foramsulfuron use in conjunction with fall-applied herbicides. The objective of this research was to determine the main and interactive effects of fall-bearing year herbicide applications and spring-nonbearing year foramsulfuron applications on hair fescue. The experiment was a 5 × 2 factorial arrangement of fall-bearing year herbicide (none, terbacil, pronamide, glufosinate, dichlobenil) and spring-nonbearing year foramsulfuron application (0, 35 g·ha−1) arranged in a randomized complete block design at lowbush blueberry fields in Portapique and Stewiacke, Nova Scotia, Canada. Spring-nonbearing year foramsulfuron applications did not reduce total tuft density or consistently reduce flowering tuft density, flowering tuft inflorescence number, or flowering tuft seed production. Fall-bearing year pronamide applications reduced hair fescue density for the 2-year production cycle, although additional bearing year density reductions occurred when pronamide was followed by spring-nonbearing year foramsulfuron applications at Stewiacke. Fall-bearing year dichlobenil applications reduced total and flowering tuft density at each site, although reductions in flowering tuft inflorescence number and seed production were most consistent when followed by spring-nonbearing year foramsulfuron applications at Stewiacke. Suppression extended into the bearing year at each site, and dichlobenil should be examined further for hair fescue control. Fall-bearing year glufosinate applications reduced hair fescue total tuft density at each site and flowering tuft density and flowering tuft seed production at Stewiacke. Fall-bearing year glufosinate applications followed by spring-nonbearing year foramsulfuron applications also reduced nonbearing year flowering tuft inflorescence number and bearing year hair fescue seedling density at Stewiacke, indicating that this treatment may reduce hair fescue seedling recruitment at some sites. Fall-bearing year terbacil applications did not suppress hair fescue and are not recommended for hair fescue management in lowbush blueberry.


Author(s):  
Reynaldo Teodoro de Fatima ◽  
Jackson Silva Nobrega ◽  
Daniel De Almeida Carreiro ◽  
Amaralina Celoto Guerrero ◽  
Adriana Silva Lima ◽  
...  

Aims: The study was conducted to evaluate the fluorescence and growth of eggplant under influence of water deficit and silicon doses. Study Design: The design was a randomized complete block design, in a 5 x 2 factorial arrangement, with four replications and one plant per plot, totaling 40 experimental units. Length and Place of Study: The research was implemented between September and November 2016, in a greenhouse of the Center of Science and Technology Agrifood, at the Federal University of Campina Grande (UFCG / CCTA), Campus of Pombal-PB, Brazil. Methods: Doses of 0, 75, 150, 225 and 300 mg L-1 of silicon and the irrigation slides of 50 and 100% of real evapotranspiration - ETr were used, which were obtained by weighing the pots daily in order to keep the weight close to the field capacity. Results: The use of 50% level of the ETr provides reductions of 5.58; 7.92 and 6.84% of fluorescence in the initial, maximum and quantum yield of the photosystem. The fresh and dry mass of the stem presented the maximum productivity (140.8 and 48.1 g) in the plants irrigated with 100% Etr and treated with doses of 106 and 110 mg L-1 of Si. Conclusion: The fluorescence and biomass of the eggplant plants is reduced with the decrease in irrigation level; while the application of silicon does not result in increment in the fluorescence and dry mass of the leaf. The 100% irrigation level of the ETr associated with the application of 108 mg L-1 of silicon resulted in the best results in stem mass accumulation.


2020 ◽  
Vol 25 (6) ◽  
pp. 2148-2155
Author(s):  
PETER VERA ◽  
◽  
MARCIA ASTORGA-ELÓ ◽  
ROLORD SEVERE ◽  
LAURA MORANTE ◽  
...  

Water is one of the main factors that influence the growth and development of plants. Balsa (Ochroma pyramidale) is a fast-growing tropical tree species with a great demand in the international market. The influence of soil, water deficit on morphological, physiological, and the growth of Balsa (Ochroma pyramidale) with and without irrigation was investigated. For this study, four random repetitions were carried out in a randomized complete block design. The plants were irrigated regularly with furrow irrigation. The timing of irrigation was based on the soil, water potential, according to treatment criteria. All pots were irrigated at 15, 30, 45, 60 and 75 days. Genomic DNA of O. Pyramidale was identified by ERIC-PCR and RAPD, while phylogenetic tree was determined using the UPGMA method. The results showed that leave number, shoot number, stem elongation and stem diameter were affected significantly (P 0.05) were observed, while stomata length remained high (> 20 µm) and stomata diameter was decreased during evaluation days in plants without irrigation compared to control. DNA of eight plants isolated showed different band profiles. In conclusion, the parameters evaluated can be used as a measure of water stress, growers should be careful when using O. Pyramidale in both nursery and orchards where water scarcity is present.


Irriga ◽  
2020 ◽  
Vol 25 (1) ◽  
pp. 87-101
Author(s):  
Rômulo Uchôa Bezerra ◽  
Thales Vinícius de Araújo Viana ◽  
Benito Moreira de Azevedo ◽  
João Valdenor Pereira Filho ◽  
Alan Diniz Lima

PRODUÇÃO E QUALIDADE DA ABÓBORA MARANHÃO SOB INFLUÊNCIA DE LÂMINAS DE IRRIGAÇÃO E DOSES DE NITROGÊNIO   RÔMULO UCHÔA BEZERRA1; THALES VINÍCIUS DE ARAÚJO VIANA2; BENITO MOREIRA DE AZEVEDO2; JOÃO VALDENOR PEREIRA FILHO3 E ALAN DINIZ LIMA4   1Departamento de Engenharia Agrícola - DENA, Universidade Federal do Ceará – Campus do Pici – CE, Avenida Mister Hull, s/n, CEP: 60455-760, Fortaleza, Ceará, Brasil, [email protected]; 2 Professores do Curso de Pós-Graduação em Engenharia Agrícola da Universidade Federal do Ceará – Campus do Pici – CE, Avenida Mister Hull, s/n, CEP: 60455-760, Fortaleza, Ceará, Brasil, [email protected]; [email protected]; 3 Professor do curso de Bacharelado em Engenharia Agronômica da Universidade Estadual do Piauí – Campus Cerrado do Alto Parnaíba – PI, Rua Almir Benvindo, s/n, Bairro Aeroporto, CEP: 64860-000, Uruçuí, Piauí, Brasil, [email protected]; 4 Professor do curso de Bacharelado em Engenharia Agrícola e Ambiental da Faculdade Terra Nordeste – FATENE – CE, Rua Coronel Correia, 1119, Centro, CEP 61600-000, Caucaia, Ceará, Brasil, [email protected].     1 RESUMO   A cultura da abóbora vem se destacando no cenário mundial devido a crescente preocupação com a questão do desafio alimentar e sua característica de produção associada a pequenas propriedades. São escassas as informações na literatura acerca das respostas da abóbora ao manejo da irrigação associada a adubação nitrogenada. Objetivou-se neste trabalho avaliar o desempenho produtivo (número, massa fresca, massa seca e produtividade) e os parâmetros de qualidade (diâmetro, comprimento, espessura da polpa e °Brix dos frutos) da cultura da abóbora sob lâminas de irrigação associadas a doses de adubo nitrogenado. Adotou-se o delineamento de blocos casualizados em parcelas subdivididas, onde nas parcelas estavam inseridas o fator doses de nitrogênio (50; 70; 100; 125% kg de N ha-1) e nas subparcelas as lâminas de irrigação (50; 75; 100; 125% da evaporação medida no tanque classe A - ‘ECA’) com quatro repetições. A pesquisa foi conduzida em campo na área experimental da Estação Meteorológica pertencente a Universidade Federal do Ceará. A produtividade máxima alcançada foi de 4269,6 kg ha-1 obtido com a combinação da lâmina de água de 444,10 mm (122,5% da ECA) e do nível de nitrogênio de 33,65 kg ha-1 de N (112,16 % do recomendado de N).   Palavras-chave: jerimum de leite, adubação, manejo da irrigação.     BEZERRA, R. U.; VIANA, T. V. de A.; AZEVEDO, B. M. de; PEREIRA FILHO, J. V.; LIMA, A. D. PRODUCTION AND QUALITY OF MARANHÃO PUMPKIN UNDER INFLUENCE OF WATER DEPTHS AND NITROGEN DOSES     2 ABSTRACT   The pumpkin crop is becoming outstanding in  the world scenario due to growing concern with the issue of food challenge and its production characteristic associated with small properties. There is little information in the literature about pumpkin responses to irrigation management associated with nitrogen fertilization. The objective of this work was to evaluate productive performance (number, fresh weight, dry weight and productivity) and quality parameters (diameter, length, pulp thickness and ° Brix of the fruits) of pumpkin culture under irrigation levels associated with doses of nitrogen fertilizer. A randomized complete block design was used in subdivided plots, where the nitrogen dose factor (50; 70; 100; 125% kg of N ha-1) was inserted in the plots and in the subplots, irrigation depths  (50; 75; 100; 125% of evaporation measured in tank class A - 'ECA') with four replicates. The research was conducted in the experimental area of the Meteorological Station belonging to the Federal University of Ceará. The maximum productivity reached was 4269.6 kg ha-1 obtained with the combination of water blade of 444.10 mm (122.5% of ECA) and nitrogen level of 33.65 kg ha-1 of N (112.16% of the recommended N).   Keywords: milk jerimum, fertilization, irrigation management.


2006 ◽  
Vol 11 (1) ◽  
pp. 139
Author(s):  
S. Cortez ◽  
S. A. Camacho ◽  
Gaspar Martínez ◽  
S. Kuruvadi ◽  
Mariano Mendoza

The objectives of this research were to study variability of growing and distribution of the root system in 10 commercial and experimental potato clones and to identify the best materials in different soil profiles. It was used a complete random block design, under greenhouse conditions at the Universidad Autónoma Agraria Antonio Narro, Saltillo, Mexico. Black polyethylene containers of 90 cm long and 30 cm diameter were used for evaluating root system. Restricted irrigation was applied to increase root growing. Experimental plot was one container with two plants. After flowering and 125 days of growing, shoot was cut. Soil in every container was divided in four sections. Shoot and roots were dried at 70 °C for 48 hours and weighted. Analysis of variance revealed highly significant differences for dry root weight among potato varieties at the four considered profiles: 0-20, 20-40, 40- 60, 60-80 cm, and for total profile (0-80 cm). Boer, Russet Burbanck and Utatlan were outstanding varieties for the total production of roots. Boer Russet Burbanck, Atlantic and Gigant varieties produced the higher amount of roots in the 60- 80 cm profile and produced a good roots growing patterns in different profiles.


2017 ◽  
Vol 4 (2) ◽  
pp. 149-161
Author(s):  
Berton Sianturi

Crassocephalum crepidioides on Cornfields in Dairi Regency had been reported tobecome more difficult to control using paraquat. The objective of the research was todetermine the characteristics and the distribution of C.crepidioides resistant to paraquatin cornfields. The experiment was carried out in two steps, the first step was screeningthe population of C. crepidioides with paraquat at the recommended dose, and the secondstep, dose-response experiment for the resistance level of C. crepidioides population withdose 0, 76, 152, 304,5, 609, 1218, and 2436 g.ai /ha. In the first step experiment, paraquatdichloride was applied at 280 g.ai/ha. The treatments were arranged in a randomized blockdesign with 3 replication. The second step experiment was that the resistant populationsconfirmed in the first experiment were sprayed for their dose-response. The treatmentswere arranged in a randomized complete block design (CRBD). The results showed thatof 30 populations of C. crepidiodes, 19 populations (63.3%) were categorized to beresistant with the mortality ranging from 10.84% to 52.08%, and 11 populations (36.7%),was categorized as high resistance with mortality of 0% to 9.21%. The level ofresistance (R/S) of R-C25, R-C27, and R-C30 populations of C. crepidioides were 12,3,14,86, and 24,83 times consecutively, compared with the susceptible population. Thenumber of C. crepidioides chlorophyl leaves in susceptible populations was significantlylower than that of a resistant populations.


2017 ◽  
pp. 31-43
Author(s):  
Berta Ratilla ◽  
Loreme Cagande ◽  
Othello Capuno

Organic farming is one of the management strategies that improve productivity of marginal uplands. The study aimed to: (1) evaluate effects of various organic-based fertilizers on the growth and yield of corn; (2) determine the appropriate combination for optimum yield; and (3) assess changes on the soil physical and chemical properties. Experiment was laid out in Randomized Complete Block Design, with 3 replications and 7 treatments, namely; T0=(0-0-0); T1=1t ha-1 Evans + 45-30-30kg N, P2O5, K2O ha-1; T2=t ha-1 Wellgrow + 45-30-30kg N, P2O5, K2O ha-1; T3=15t ha-1 chicken dung; T4=10t ha-1 chicken dung + 45-30-30kg N, P2O5, K2O ha-1; T5=15t ha-1 Vermicast; and T6=10t ha-1 Vermicast + 45-30-30kg N, P2O5, K2O ha-1. Application of organic-based fertilizers with or without inorganic fertilizers promoted growth of corn than the control. But due to high infestation of corn silk beetle(Monolepta bifasciata Horns), its grain yield was greatly affected. In the second cropping, except for Evans, any of these fertilizers applied alone or combined with 45-30-30kg N, P2O5, K2O ha-1 appeared appropriate in increasing corn earyield. Soil physical and chemical properties changed with addition of organic fertilizers. While bulk density decreased irrespective of treatments, pH, total N, available P and exchangeable K generally increased more with chicken dung application.


Sign in / Sign up

Export Citation Format

Share Document