scholarly journals Florpyrauxifen-Benzyl Selectivity to Rice in Brazilian Conditions

Agriculture ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1270
Author(s):  
Juan Camilo Velásquez ◽  
Angela Das Cas Bundt ◽  
Edinalvo Rabaioli Camargo ◽  
André Andres ◽  
Vívian Ebeling Viana ◽  
...  

Florpyrauxifen-benzyl (FPB) is a new class of auxinic herbicide developed for selective weed control in rice. This study aimed to evaluate the effect of environmental conditions, P450 inhibitors, rice cultivar response, and gene expression on FPB selectivity in rice. Field experiments established in a randomized block design showed that rice plant injury due to two FPB rates (30 and 60 g ai ha−1) was affected by planting time and rice stage at herbicide application. The injury was higher at the earliest planting season and more in younger plants (V2) than larger (V6 and R0). However, no yield reduction was detected. Under greenhouse conditions, two dose-response experiments in a randomized block design showed that spraying malathion (1 kg ha−1) before FPB application did not reduce herbicide selectivity. The addition of two P450 inhibitors (dietholate and piperonyl butoxide, 10 g a.i. seed-kg−1 and 4.2 kg ai ha−1, respectively) decreased the doses to cause 50% of plant injury (ED50) and growth reduction (GR50). However, it seems not to compromise crop selectivity. Pampeira cultivar showed lower ED50 and GR50 than IRGA 424 RI. A growth chamber experiment was conducted in a completely randomized design to evaluate the gene expression of rice plants sprayed with FPB (30 and 60 g ai ha−1). Results showed downregulation of OsWAKL21.2, an esterase probably related to bio-activation of FPB-ester. However, no effect was detected on CYP71A21 monooxygenase and OsGSTL transferase, enzymes probably related to FPB degradation. Further research should focus on understanding FBP bio-activation as the selective mechanism.

2007 ◽  
Vol 87 (4) ◽  
pp. 639-646 ◽  
Author(s):  
N. E. Odongo ◽  
D. McKnight ◽  
A. KoekKoek ◽  
J. W. Fisher ◽  
P. Sharpe ◽  
...  

The objective of this study was to assess the long-term effects of feeding a diet with no mineral phosphorus (P) supplementation on performance and P excretion in high-yielding dairy cows. In exp. 1, 24 primiparous (PP) and 40 multiparous (MP) Holstein cows were allocated to one of two treatments at calving: (1) regular corn silage and alfalfa haylage based milking cow total mixed ration (TMR; 0.42% P diet) or (2) milking cow total mixed ration (TMR) without supplemental mineral P (0.35% P diet) in a completely randomized design. The trial lasted until after two lactations were completed or the cow was culled. In exp. 2, eight MP Holstein cows (108 ± 8.0 d in milk) were used to determine P digestibility and retention in a completely randomized block design. In exp. 1, the 0.35% P diet cows had lower body weight, body condition score and milk urea nitrogen and higher faecal P than the 0.42% P cows. The dry matter intake (DMI) of PP cows on the 0.35% P diet was lower than that of PP cows on the 0.42% P diet. There was no difference in the DMI of MP cows. The P intake of 0.35% P diet PP cows was 30% lower than that of 0.42% P diet PP cows. The P intake of 0.35% P diet MP cows was 20% lower than that of 0.42% P diet MP. The digestibility coefficient of P for the 0.35% P diet was higher than that for the 0.42% P diet. These results suggest that the forages used in the present study contained adequate amounts of P to sustain milk production in high-yielding MP cows. However, for PP cows some mineral P supplementation is recommended especially during early lactation. Key words: Phosphorus, environmental pollution, intensive dairy operations


Revista CERES ◽  
2014 ◽  
Vol 61 (1) ◽  
pp. 62-69
Author(s):  
Gessimar Nunes Camelo ◽  
Geraldo Antonio de Andrade Araújo ◽  
Renildes Lucio Ferreira Fontes ◽  
Luiz Antonio dos Santos Dias ◽  
José Eustáquio de Souza Carneiro ◽  
...  

The effect of molybdenum (Mo) on common bean grown in desiccated corn stover in a no-tillage system was evaluated under two application modes: Mo mixed with the desiccant glyphosate and Mo direct spray to the bean leaves. The treatments (four replicates) were assigned to a completely randomized block design in a split-plot arrangement with the application of Mo (0, 100, 200, 400 and 800 g ha-1) mixed with glyphosate in the main plots and Mo foliar spray (0 and 100 g ha-1) in the sub-plots. The field experiments were carried out in 2009 and 2010 in the municipality of Coimbra, Minas Gerais State, with the common bean cultivar Ouro Vermelho. Mo mixed with glyphosate had neither an effect on common bean yield nor on the Mo and N contents in leaves, however it increased the Mo and N contents in seeds. Application of Mo via foliar spray increased Mo content in leaves and Mo and N contents in seeds. The reapplication of molybdenum with glyphosate for desiccation in subsequent crops caused a cumulative effect of Mo content in bean seeds.


2013 ◽  
Vol 31 (1) ◽  
pp. 08-14 ◽  
Author(s):  
Edilson Costa ◽  
Taynara G de Souza ◽  
Gleciane de L Benteo ◽  
Katiane SS Benett ◽  
Cleiton GS Benett

The okra grows well in hot weather, finding favorable conditions for development in Brazil. We evaluated the production of okra seedlings and productivity. The experiment was conducted in the experimental area of the State University of Mato Grosso do Sul, in Aquidauana. In the seedling phase we tested substrates (100% triturated cassava stems, 75% triturated cassava stems and 25% vermiculite, 50% triturated cassava stems and 50% vermiculite, 25% triturated cassava stems and 75% vermiculite and 100% vermiculite). These substrates were placed in two protected environments (nursery with black screen, 50% of shading, and aluminized screen, 50% of shading). Each environment was considered an experiment conducted in completely randomized design with eight replications. After that we realized joint analysis. In the field, a total of 10 treatments generated from combinations of environments and substrates (2 environments x 5 substrates) were distributed in a randomized block design with four replications. The average proportions of cassava stems and vermiculite may be suitable for okra seedlings. The results of shoot and total dry phytomass indicate that the aluminized screen can be recommended for okra seedlings production when the substrate with a 1:1 ratio is used. Seedlings grown on higher percentages of vermiculite anticipate production, while seedlings produced only in cassava stems tend to slow it down. The aluminized screen tends to increase the yield of okra seedlings. Average proportions of vermiculite and cassava stems for seedling production under aluminized screen, provide more fruits and yield of okra in Aquidauana.


Author(s):  
C. Sivakumar ◽  
A. Krishnaveni ◽  
M. Pandiyan ◽  
N. Tamilselvan

Field experiments were conducted to study the effect of establishment techniques on yield and economics of red gram [Cajanus cajan (L.)] under irrigated condition at Regional Research Station, Tamil Nadu Agricultural University, Paiyur - 635 112,Tamil Nadu, India during Kharif season of 2013-14 and 2014-15 respectively in randomized block design with four replications. The treatments are line sowing/dibbling of seeds, sowing behind the country plough, sowing in polybag and transplanting at 25 and 40 DAS, sowing in portrays and transplanting in 25 and 40 DAS. The redgram variety LRG 41 was used for study. The results revealed that, dibbling of seeds in lines recorded higher grain yield of 2351 kg ha-1, net income of Rs.99495/- and B:C ratio of 3.39. Thus, dibbling of seeds in lines recorded 6% higher over sowing in poly bag and transplanting at 25 DAS and 27% higher yield over sowing behind the country plough. Considering yield and economics, line sowing seems to better option for the farmers followed by sowing in polybags and transplanted in 25 DAS. Under transplanted situation, transplanting of seedlings at 30 DAS was more suitable where the monsoon was delayed for 30 to 45 days under rainfed situation. 


2018 ◽  
Vol 85 (0) ◽  
Author(s):  
Suzete Fernandes Lima ◽  
Leandro Spíndola Pereira ◽  
Gustavo Dorneles Sousa ◽  
Simonny Araújo Vasconcelo ◽  
Adriano Jakelaitis ◽  
...  

ABSTRACT: The use of herbicide underdoses allows minimizing the competition of grasses on annual crops, enabling simultaneous cultivation. In this context, the objective of this study was to investigate glyphosate underdoses on the suppression of the initial growth of three Panicum maximum cultivars aiming at the integrated cultivation, in addition to the effects of forage species on the incidence and development of weeds. Three field experiments were conducted. The experimental design was a randomized block design with four replications and eight treatments consisting of increasing glyphosate doses (0, 54, 108, 270, 378, 540, 756, and 1,080 g a.e. ha−1). An atrazine dose of 1,200 g a.i. ha−1 was added to each treatment. Plant phytotoxicity assessments were performed at 7, 14, 21, and 28 days after application. At 80 and 125 days after sowing, the assessments of total dry matter production, leaf dry matter, stem dry matter, and leaf to stem ratio were carried out, in addition to density and dry matter production of weed community. Glyphosate underdoses below 215, 65, and 90 g a.e. ha-1 have a potential to be investigated aiming at the management of P. maximum cv. Atlas, P. maximum cv. Mombasa, and P. maximum cv. Tanzania under intercropping. The three forage species are effective in suppressing weeds.


2020 ◽  
pp. 1095-1101
Author(s):  
Fábio Henrique Krenchinski ◽  
Caio Antonio Carbonari ◽  
Edicarlos Batista de Castro ◽  
Danilo Morilha Rodrigues ◽  
Victor José Salomão Cesco ◽  
...  

Several maize hybrids that present the phosphinothricin acetyltransferase gene (pat) are available in the market. However, these hybrids have different resistance levels to glufosinate herbicides. The objective of the present work was to evaluate the resistance of maize hybrids containing the pat gene (as a selection marker) to glufosinate. Field experiments were conducted in two sites in the 2016/2017 crop season, using a randomized block design with a 2×7 factorial arrangement and four replications. The treatments consisted of two glufosinate rates (0 and 500 g ha-1) and seven maize hybrids, six containing the pat gene as a selection marker (Herculex®, Agrisure-TL®, Herculex Yieldgard®, Leptra®, Viptera-3®, and Power-Core®) and one without the pat gene (VT PRO®). Two field experiments were conducted in different sites. The analyzed variables were: ammonia accumulation, electron transport rate (ETR), percentage of injuries, 100-grain weight, and grain yield. The glufosinate-susceptible maize hybrid presented higher ammonia accumulations, lower ETR, and high percentage of injuries (100%), which caused total loss of grain production. Considering the evaluated glufosinate-resistant maize hybrids, Viptera-3 and Agrisure-TL presented the highest ammonia accumulations and percentages of injuries, and lower ETR than the other hybrids. The grain yield of glufosinate-resistant maize hybrids was not reduced due to the application of the 500 g ha-1 of glufosinate. Thus, glufosinate-resistant maize hybrids containing the pat gene are resistant to the application of 500 g ha-1 of glufosinate, and this practice can be recommended for maize crops.


Weed Science ◽  
1999 ◽  
Vol 47 (6) ◽  
pp. 720-728 ◽  
Author(s):  
David W. Clausnitzer ◽  
Michael M. Borman ◽  
Douglas E. Johnson

Two field experiments were conducted from 1993–1994 through 1995–1996 growing seasons in Harney County, OR, to determine the relative competitive abilities ofElymus elymoides(squirreltail) a native perennial range grass, andTaeniatherum caput-medusae(medusahead), an exotic annual grass weed. The 1993–1994 growing season was very dry, 1994–1995 was dry, and 1995–1996 was wetter than average. One experiment tested seedlings vs. seedlings in each of three seasons. The second experiment tested seedlings plus second- and third-year establishedE. elymoidesplants vs. 77caput-medusaeover 2 yr. Biomass, seed production, and soil moisture utilization 15, 30, 45, and 60 cm deep by the two species were measured. A randomized block design with factorial arrangement was used, with 25 2.25-m2plots per block. Initial seeding densities of each species were 0, 10, 74, 550, and 4,074 seeds m−2in all combinations of density. In the seedling vs. seedling experiment, intraspecific competition by 77caput-medusaeon itself was always significant (P ≤ 0.10) for both biomass and seed production. Interspecific competition byE. elymoidesseedlings onT. caput-medusaebiomass and seed production was not significant (P ≥ 0.10) in 2 of 3 yr and was always less than intraspecific competition by 77caput-medusae. Only 0.4% ofE. elymoidesseed germinated, and no seed was produced in the very dry first year, but 84% of remaining seed was viable for the next year, which had better moisture conditions for germination and establishment. Interspecific competition affected (P ≤ 0.10)E. elymoidesseedling biomass and seed production throughout the study. Intraspecific competition affected (P ≤ 0.10) seedlingE. elymoidesseed production in the dry year but not in the wetter than average year. In the matureE. elymoidesexperiment, intraspecific competition byT. caput-medusaeon weight and seed production per plant was greater than interspecific competition fromE. elymoides. Seedling/matureE. elymoidesreducedT. caput-medusaeweight per plant in the dry year but the effect was not biologically significant. Larger, matureEelymoidesplants produced 600 to 3,000 seeds per plant during the wet year; neither intra- nor interspecific competition was a factor.Taeniatherum caput-medusaewas better able to access deeper soil moisture and was more aggressive at extracting soil moisture than wereE. elymoidesseedlings in the wet year. Cold soils and low oxygen due to wet soils may have restrictedE. elymoidesseedling root activity. MatureE. elymoidesplants did not appear restricted by cold soils or low oxygen. Established second- and third-yearE. elymoidesplants were able to compete for soil moisture down to 45 cm. The generally greater interspecific competitive effects ofT. caput-medusaeonE. elymoidesthan vice versa suggested that it will be difficult to establish anE. elymoidesstand in an existingT. caput-medusaecommunity without first suppressingT. caput-medusae. IndividualE. elymoidesplants did establish and were productive with and withoutT. caput-medusaecompetition.


2019 ◽  
Vol 49 (2) ◽  
Author(s):  
Lucas Matias Gomes ◽  
Cláudia Silva da Costa Ribeiro ◽  
Carlos Francisco Ragassi ◽  
Lorena Sousa Silva ◽  
Francisco José Becker Reifschneider

ABSTRACT: The objective of this study was to evaluate the plant and fruit characteristics in advanced lines of Jalapeño pepper for mechanical harvesting. Thus, two experiments were carried out in the field. Experiment I (2015) was conducted as a randomized block design (three replications and eight plants per plot) and Experiment II (2016) in a completely randomized design (five replications and ten plants per plot). In 2015, lines CNPH 30,112, CNPH 30,118, CNPH 30,147, CNPH 30,159, CNPH 30,183, and CNPH 30,245 were evaluated, together with the control ‘BRS Sarakura’. Significant differences were detected for fruit and plant characteristics (P<0.05). Lines CNPH 30,118, CNPH 30,147, CNPH 30,159, and CNPH 30,245 were selected based on plant height and height of the first bifurcation, earliness, and yield. They were evaluated again in 2016, together with ‘BRS Sarakura’ and ‘Jalapeño Plus F1’ as controls. In 2016, CNPH 30,159 and CNPH 30,118 were selected due to their potential for mechanical harvesting. They were evaluated for height of the first bifurcation (>10cm), large fruits (11 cm x 4 cm), high pulp firmness (11 N), wall thickness (about 5mm), and content of capsaicinoid substances (>50,000 SHU). Selected lines are undergoing additional field evaluation for mechanical harvesting with the Etgar Moses 1010 pepper harvester.


Author(s):  
Paola Alfonsa Vieira Lo Monaco ◽  
Josean de Castro Vieira ◽  
João Nacir Colombo ◽  
Marcelo Rodrigo Krause ◽  
Gustavo Haddad Souza Vieira ◽  
...  

Considering the need to reduce costs in the production of seedlings, the use of agricultural wastes becomes essential. The objective of this study was to evaluate a substrate composed of agricultural residues replacing the commercial substrate. The experiment was carried out in two phases. For the first phase, seedling production, we used a completely randomized design with six treatments and eight replications, using commercial substrate (Bioplant®) and five treatments with increasing proportions of moinha/descending proportions of rice husk (0/40; 10/30; 20/20; 30/10 and 40/0%), and fixed proportions of coconut fiber (15%) and pine bark (45%). We evaluated plant height, stem diameter, number of leaves, root and shoot dry masses, and Dickson quality index at 33 days after sowing. In the second experiment, cabbage development under field conditions, the treatments were maintained with four replications, using the randomized block design. We evaluated cycle length, compactness, head and stem diameter, number of basal external leaves, mass of fresh matter of the head, and commercial yield. We recommend a substrate composed of 40% moinha, 15% coconut fiber, and 45% pine bark in the production of cabbage seedlings, replacing the commercial substrate.


2016 ◽  
Vol 42 (4) ◽  
pp. 303-307
Author(s):  
Vander Rocha Lacerda ◽  
◽  
Diemesson San Tiago Mendes ◽  
Fernando da Silva Rocha ◽  
Maria de Fátima Gonçalves Fernandes ◽  
...  

ABSTRACT Propagation of “coquinho-azedo” (Butia capitata) is limited due to dormancy and high incidence of fungi in its seeds. The aim of this study was to evaluate the effect of treating “coquinho-azedo” seeds with different concentrations of bactericide and/or fungicide on the incidence of fungi and on the germination of seeds. Thus, B. capitata seeds were immersed in four doses of the bactericide kasugamycin (0, 1.5, 3.0 and 4.5 mL/L) and/or in four concentrations of the fungicide carbendazim+ thiram (0, 2.92, 5.84 e 8.75 mL/Kg), totaling 16 treatments. After the treatments, the operculum was removed from the seeds, which were placed on trays containing autoclaved sand, covered with transparent plastic film and kept in the nursery. In the germination test, treatments were distributed in randomized block design, factorial arrangement of 4x4 (bactericidal doses x fungicide doses), with four replicates of 50 seeds per plot. For the test of seed health quality, the Blotter test was employed in completely randomized design, using 20 replicates and 10 seeds. Health quality and germination were evaluated at 15 and 40 days after the treatment of seeds, respectively. There was no interaction between the bactericide and the fungicide on germination and control of fungi associated with seeds. However, there was an effect of fungicide concentrations on the evaluated parameters. We observed a negative correlation between the concentrations of the fungicide carbendazim + thiram and fungal incidence, and a positive correlation between the fungicide concentrations and seed germination. Therefore, fungicide treatment reduces the fungal incidence and provides better germination of B. capitata seeds.


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