EFFECTS OF SEMIOCHEMICAL BAITING ON THE ATTRACTIVENESS OF FELLED AND UNFELLED LETHAL TRAP TREES FOR SPRUCE BEETLE, DENDROCTONUS RUFIPENNIS (KIRBY) (COLEOPTERA: SCOLYTIDAE), MANAGEMENT IN AREAS OF HIGH AND LOW BEETLE POPULATIONS

1990 ◽  
Vol 122 (2) ◽  
pp. 373-379 ◽  
Author(s):  
D.R. Gray ◽  
E. Holsten ◽  
M. Pascuzzo

AbstractA two by two factorial experiment in a randomized complete block design tested single and combined effects of tree felling and semiochemical baiting on the attractiveness of spruce (Picea spp.) trees treated with monosodium methanearsenate (MSMA) to Dendroctonus rufipennis (Kirby) in British Columbia and Alaska. In British Columbia, tree felling and semiochemical baiting had significant effects on attack density, but in Alaska only tree felling had a significant effect. Semiochemical baiting had a significant effect on within-tree attack distribution in British Columbia but cot in Alaska, regardless of the felling treatment. The felled treatment captured more beetles than the not-felled treatment regardless of the baiting treatment in British Columbia, but only in the absence of a semiochemical bait in Alaska. The differences between the two locations may have been caused by lower temperatures and beetle population density in Alaska. Effective spruce beetle management with MSMA-treated trees requires tree felling, and beetle capture can be improved with the use of a semiochemical bait.

2017 ◽  
Vol 35 (3) ◽  
pp. 425-427
Author(s):  
Jana Koefender ◽  
André Schoffel ◽  
Diego P Golle ◽  
Candida E Manfio ◽  
Alice PB Dambróz ◽  
...  

ABSTRACT The purpose of this work was to evaluate the influence of cutting the apex of the main stem of marigold plants on floral capitula yield. The experiment was carried out in a randomized complete block design, with five replicates. The following removal stages of the main stem apexes were studied: control (without pruning), up to 10 leaves, up to 15 leaves and visible flower bud. Three harvest periods were also evaluated: July, August and September, composing a factorial experiment in a 4x3 arrangement. The diameter, number, fresh matter and the dry capitula were evaluated. The most significant effect of cutting the apex of the main stem on fresh and dry matter of the capitula was obtained when the technique was performed at the time the plants had up to 15 leaves and visible flower bud. The harvesting performed in September showed to be the most promising, since it presented the larger diameter, higher number and higher fresh matter and the dry capitula.


2021 ◽  
Vol 2021 ◽  
pp. 1-16
Author(s):  
Erasmus Narteh Tetteh ◽  
Eric Owusu Danquah ◽  
Akwasi Adutwum Abunyewa ◽  
Caleb Melenya Ocansey ◽  
Emmanuel Amoah Boakye ◽  
...  

A three-year field trial was conducted between 2014 and 2017 in the Ellembelle and Jomoro districts of the Western region of Ghana where rubber production is common to determine the optimum population density of plantain when grown in combination with immature rubber tree crops. The trials were arranged in a Randomized Complete Block Design with 3 replications. The treatments were sole rubber, sole plantain, and three intercrops of one row of plantain in between two rows of rubber, two rows of plantain in between two rows of rubber, and three rows of plantain in between two rows of rubber. The rubber clone used was GT1 while the variety of plantain used was false horn. The results showed that population density of plantain had significant effect on the growth of the associated rubber. Growing plantain at closer spacing of 1.5 m under the high-density plantain treatment significantly increased plantain yield compared to the other cropping systems. There was a significant positive relationship between population density of plantain and the rubber tree growth and development. The optimum population density of plantain when intercropped with rubber was 1,666/ha. The study showed intercropping was advantageous over sole cropping for both crops.


2017 ◽  
Vol 69 (4) ◽  
pp. 1039-1046 ◽  
Author(s):  
B.C. Pedreira ◽  
P.L. Barbosa ◽  
L.E.T. Pereira ◽  
M.A. Mombach ◽  
L.F. Domiciano ◽  
...  

ABSTRACT The objective of this study is to verify the population density and the dynamics of tillering in the Marandu palisade grass sward subjected to nitrogen (N) fertilization strategies, characterized by the N supply via urea or bacterial inoculant (Azospirillum brasilense). The treatments comprised of four nitrogen fertilization strategies: (A) Without fertilization, (B) 80 kg N/ha, (C) inoculant (A. brasilense), and (D) 80 kg N/ha + inoculant, distributed in a randomized complete block design, with three replications. The nitrogen supply strategies were evaluated during six periods: October, November, and December (2012) as well as January, March, and April (2013). The nitrogen dose or inoculant had no effect on the tiller appearance rate (TAR), tiller mortality rate (TMR), tiller survival rate (TSR), or tiller population density (TPD). However, these variables were influenced by the season. The TAR and TSR were higher at the beginning of the experimental period (October) and lower towards the end of the period (March-April), whereas, TMR and TPD exhibited the opposite behavior, with lower values in October and higher from January onward. Neither the nitrogen nor the inoculant influenced the population dynamics of the tillers in Marandu palisade grass.


2015 ◽  
Vol 38 ◽  
pp. 16-26
Author(s):  
Michael Ojore Ijoyah ◽  
J.A. Idoko ◽  
T. Iorlamen

Field experiments were conducted from July to October, during 2012 and 2013 cropping seasons, at the Research Farm, University of Agriculture, Makurdi, Nigeria, to evaluate the effects of intra-row spacing of sesame and frequency of weeding on yields of maize-sesame intercrop. The trial was a 3 x 3 factorial experiment fitted in a randomized complete block design with four replications. Nine of the treatments consisted of intercropped maize with sesame sown at the intra-row spacing of 10 cm, 15 cm and 20 cm, and at the varied weeding frequencies: maize-sesame intercrop sown on plots weeded once (1x) at 3 weeks after planting (WAP); maize-sesame intercrop sown on plots weeded twice (2x) at 3 and 6 WAP; maize-sesame intercrop sown on plots not weeded (NW). Sole sesame and sole maize respectively sown at their recommended intra-row spacing of 10 cm and 30 cm and at their recommended frequency of weeding (2x at 3 and 6 WAP) constituted the tenth and eleventh treatments, which also served as control plots. The results obtained showed that in a maize-sesame intercrop, increasing intra-row spacing of sesame up to 20 cm, on plots weeded 2x at 3 and 6 WAP, significantly (P≤0.05) produced the highest intercrop yields of maize and sesame. This level of treatment not only recorded the lowest competitive pressure, but gave the highest total intercrop yields, highest land equivalent coefficient values (1.01 and 1.13 respectively, in years 2012 and 2013), indicating the highest yield advantage, and highest land equivalent ratio (LER) values of 2.11 and 2.25 respectively recorded for years 2012 and 2013. With these LER values, 52.6 % and 55.6 % of land were respectively saved in years 2012 and 2013, which could be used for other agricultural purposes. The implication of study showed that, to maximize intercrop yields of maize and sesame in a maize-sesame intercrop, the appropriate intra-row spacing for sesame is 20 cm, while the optimal frequency of weeding is 2x at 3 and 6 WAP. This should therefore, be recommended for Makurdi location, Nigeria.


2020 ◽  
Vol 16 (2) ◽  
pp. 33-37
Author(s):  
A.I. Onyenso ◽  
K.A. Nwobodo ◽  
A.M. Yakubu ◽  
L.N. Onyenweaku

Alley cropping or hedgerow intercropping is one of the many sub-systems of agroforestry technology. A 5 x 3 factorial experiment in a Randomized Complete Block Design (RCBD) with three replications was used to determine the effect of four alley woody species and three plantain cultivars on the yield of 60-day cowpea grain in the 2017 and 2018 farming seasons. The Alley species, plantain cultivars and Alley species x plantain cultivars treatment interactions showed no significant effects (p<0.05) on cowpea grain yield. Students t-test on the two farming seasons showed significant increase in yield of cowpea grain in 2018 than in 2017. Alley cropping technology could increase 60-day cowpea grain yield due to improved soil fertility in the system. Keywords: alley cropping, yield, 60-day cowpea, alley woody species, plantain cultivars


Author(s):  
Maryam Abdullahi ◽  
Abubakar Bello

The study aimed to determine the effects of different levels of phosphorous and zinc fertilizers on the yield and nutrient uptake of maize (Zea mays L.) The experiments were  conducted in a factorial experiment under Randomized Complete Block Design (RCBD) to determine the effect of P and Zn applications on TZL white composite improved variety            of maize. Four levels of phosphorus (0, 10, 20 and 30 kg P ha-1) and three levels of zinc (0, 5 and 10kg Zn ha-1) were applied on experimental plots of 4.5m x 5m replicated thrice.  The results shows no significant differences in both the  years however, highest mean values of 2327.5 kg ha-1  and 2191.5 kg ha-1 was recorded at 20 kg P ha-1 and 10 kg Zn ha-1 Application of P and Zn at different rates increases their uptake in the stover with highest values of 22.57 mg -1 kg  and 7.8 mg -1 kg  in 2018  at 30 kg Pha-1 and 18.40 mg -1 kg  and 5.21 mg -1 kg  at 20 kg Pha-1  in 2019. While 26.54 mg -1 kg and 21.85 mg -1 kg in 2018 at 10 kg Znha-1 and 6.76 mg -1 kg and 5.27 mg -1 kg in 2019 with 0 kg Znha-1 respectively. It is therefore recommended the best results of the application of 30kg P ha-1 and 10 kg Zn ha -1 should be adopted for optimum yield of maize.


The study was conducted in the nursery of Hort. Dept., College of Agriculture and Forestry, Mosul University, Iraq, during 2018 season to study the response of budded "Zaghinia" apricot on seedlings rootstock to bio, organic and chemical fertilizers, and their effects on seedling growth. The studied factors were as follows: Bio fertilizer Fulzyme (0, 1 and 2 g.seedling-1 ), Organic fertilizer (rice residue) (0, 1 and 2 kg.seedling-1 ) and DAP fertilizers (0, 5 and 10 gm.seedling-1 ). The study was performed by using split-split plots within factorial experiment in Randomized Complete Block Design (RCBD), with 3 factors and 3 replicates, by using 6 seedlings for each treatment. Treatment means were compared by using Duncan multiple levels at 5% p. The most important results obtained were as follows: 1 and 2 g.seedling-1 of bio fertilizer (Fulzyme) resulted in a significant increase in most of traits, especially leaves content of P and Zn, while the addition of organic fertilizer (rice residue) at 1 and 2 kg.seedling-1 gave a significant increase in most of studied traits (leaves N, P, K and Zn, Chemical fertilizer (DAP) at the levels 5 and 10 g.seedling-1 affected significantly most of the studied traits, especially leaves K and Zn. The double interaction has a high role in seedlings growth, especially the interaction between bio fertilizer (Fulzyme) and organic fertilizer (rice residue), which affected highly in leaves N, P & Zn and the triple interference also gave a significant increase in all studied traits.


2020 ◽  
Vol 33 (2) ◽  
pp. 196-206
Author(s):  
Murtadha A. A. Alfaris ◽  
Salim Almaliki ◽  
Sadiq J. Muhsin

The experiment was performed using locally manufactured subsoiler plow provided with wings on the outside of shallow tines feet to study the impact of adding the wings and depth of tillage on the disturbance area of soil, soil pulverization index (mean weight diameter, MWD) and the equivalent energy of soil pulverization (Eq EP) in clay soil. This experiment was done in Randomized Complete Block Design (RCBD), with three replications having a factorial experiment. Three tillage depths (40, 50, and 60cm) with and without wings on the feet of shallow tines were used. The results showed that the impact of adding wings and tillage depths had a significant effect on the disturbance area, soil pulverization index and the equivalent energy of soil pulverization (p < 0.05). The treatment of adding wings on shallow tines (S+shw) has pre-eminence in studied factors. The disturbed area increased by 11.11, 14.29 and 9.80%, the MWD decreased by 27.33, 32.31 and 19.38% and the Eq EP increased by 43.19, 53.03 and 25.13% when the depth of tillage increased from 40, 50 and 60cm respectively.


2003 ◽  
Vol 3 (1) ◽  
pp. 17-20
Author(s):  
Lestari Wibowo ◽  
I Gede Swibawa ◽  
Tejo Muryanto

The use of traps to control lowland rats. The lowland rat (Rattus rattus argentiventer ) is one of the importance pests of rice in Indonesia.  The rat may cause serious damage on rice and other crops.  This study was aimed to determine the affectivity of rat trappings.  Traps were set in Pekalongan Central Lampung, from  October to December 2002.  The treatments were arranged in a factorial experiment in randomized complete block design.  The first factor was the type of traps (bamboo trap and wired “bubu” trap) while the second factor was the location of traps (rice field, swamp, tertiary irrigation canal, and rice plot borders). The catches show that there were no interaction between the trap type and trap location. In addition, more rats were caught in bamboo than those in wired “bubu” trap.  The highest number of rat catches was from the swamp area.          


1988 ◽  
Vol 120 (1) ◽  
pp. 85-94 ◽  
Author(s):  
L. Safranyik ◽  
D.A. Linton

AbstractThe distribution of spruce beetle attacks and length of associated egg galleries were investigated on 21 spruce stumps over a 4-year period in central British Columbia. Attack density formed a distinct vertical gradient which peaked near the duff line at about one-third stump height above the mineral soil. The proportion of attacks on the stumps that were located below the duff was linearly related to the ratio of stump height below duff and total stump height above mineral soil. Attack density was significantly higher below the duff than above. A three-parameter exponential function gave satisfactory fit to the attack density gradient on normalized stump height. A discrete-step theoretical model was also developed based on assumptions regarding beetle behavior during landing and imitation of the egg gallery and the physical characteristics of the host. This model gave an excellent fit to the attack density gradient as an average process over all stumps. Average egg gallery length was a curvilinear function of attack density with maximum average egg gallery length occurring at about 0.33 attacks per 100 cm2.


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