scholarly journals Rekrutmen Box Mussel, Septifer Bilocularis L. Efek Substratum Dan Kepadatan Dewasa

2019 ◽  
Vol 3 (2) ◽  
pp. 42-46
Author(s):  
Medy Ompi
Keyword(s):  
Field Experiments ◽  
Adult Density ◽  
Coral Rubble ◽  
North Sulawesi ◽  
Four Levels ◽  
Intertidal Population ◽  
New Recruits ◽  
Mussel Density

An intertidal population of Septifer bilocularis L. was studied in Tongkeina, North Sulawesi, Indonesia. Open and closed cages were applied in field experiments to study the effects of four types of substrata on settling of S. bilocularis:  live shells of adults, dead shells, coral rubble, and sand.  Each substratum was tested with four levels of adult mussel density: 0, 10, 50, 100 individuals per compartment. The number of recruits as a function of cage, substratum, and adult density was analysed using Two-way ANOVA. The experiment showed that new recruits were affected by the substratum but not by the density of adults. The surface of adult box mussels was the most attractive substratum for recruits

scholarly journals Yield response of summer country bean to boron and molybdenum fertilizer

2015 ◽  
Vol 40 (1) ◽  
pp. 71-76 ◽  
Author(s):  
Shamima Nasreen ◽  
MA Siddiky ◽  
R Ahmed ◽  
RP Rannu
Keyword(s):  
Significant Influence ◽  
Detrimental Effect ◽  
Field Experiments ◽  
Agricultural Research ◽  
Yield Response ◽  
Agricultural Research Institute ◽  
Pod Yield ◽  
Four Levels ◽  
Fertilizer Combination ◽  
Higher Doses

Field experiments were conducted in the Grey Terrace Soil (Aeric Albaquept) under AEZ-28 at the Bangladesh Agricultural Research Institute (BARI) farm, Gazipur during summer seasons of 2010 and 2011 to determine the optimum rate of boron and molybdenum combination for maximizing the yield of summer country bean (var. BARI Sheem-3). Four levels each of B (0, 1, 2 and 3 kg ha-1 ) and Mo (0, 0.5, 1.0 and 1.5 kg ha-1 ) were used as treatment variables. The results indicated that application of B and Mo fertilizer combination exerted significant influence on the number of pods plant-1 , individual pod weight and pod yield ha-1 in both the years. The highest pod yield (9.58 t ha-1 in 2010 and 9.42 t ha-1 in 2011) was produced by the combination of 2 kg B and 1.5 kg Mo ha-1 and it was statistically identical with 2 kg B and 1.0 kg Mo ha-1 combination. Addition of B beyond 2 kg ha-1 along with higher doses of Mo created a detrimental effect to reduce yield irrespective of years. The results revealed that application of 2 kg B and 1 kg Mo ha-1 combination with a blanket dose of 50 kg N, 40 kg P, 60 kg K and 20 kg S ha-1 plus cowdung 5 t ha-1 might be optimum for summer country bean cultivation in Grey Terrace Soil of Gazipur.Bangladesh J. Agril. Res. 40(1): 71-76, March 2015

Seed Priming Influences the Seed Quality and Activities of Nitrate Assimilation and Anti-Oxidant Enzymes in Pigeon Pea Seedlings

2020 ◽  
Author(s):  
T. N. Tiwari ◽  
D. K. Agarwal
Keyword(s):  
Field Experiments ◽  
Seed Quality ◽  
Tap Water ◽  
Nitrate Assimilation ◽  
Seed Priming ◽  
Pigeon Pea ◽  
Quality Parameters ◽  
Organic Salt ◽  
Anti Oxidant ◽  
Four Levels

Field experiments were conducted with four levels of seed priming including control and two varieties of pigeon pea at ICAR-Indian Institute of Seed Science, Mau during three consecutive years (2011-12 to 2013-14). One-year-old seeds of pigeon pea varieties (Bahar and Malviya-13) were primed with growth regulator (100 ppm GA3), in-organic salt (0.2% KNO3) and tap water (sanitized) separately for 06 hrs. and sown in field under RBD with 03 replications. Observations were recorded on seed quality parameters, biochemical attributes including nitrate assimilatory enzymes and activities of anti-oxidant enzymes during seedling stage. Seed quality parameters including germination, seedling growth and vigor indices were significantly enhanced through seed priming with GA3 followed by KNO3 and tap water over unprimed control. Biochemical attributes viz; chlorophyll a andb contents, were more influenced with GA3 priming followed by KNO3 and tap water whereas the proline accumulation was reduced with priming treatments and maximum reduction was noted with GA3 followed by KNO3 and tap water. Enhancement in nitrate assimilatory enzymes including nitrate and nitrite reductase activities was more with KNO3 priming followed by GA3 and tap water. Anti-oxidant enzymes activities including Catalase, Peroxidase and Super Oxide Dismutase were also increased significantly by KNO3 priming followed by GA3 and tap water over unprimed control.

Boll Removal Studies Provide Insights into Compensation Ability of Virginia Cotton: A Necessary Step for Further Improvement of Insect Management Strategies

2006 ◽  
Vol 41 (2) ◽  
pp. 147-154
Author(s):  
D. Ames Herbert ◽  
Sean Malone ◽  
Susanne Aref ◽  
Joel Faircloth ◽  
Ozzie Abaye
Keyword(s):  
Field Experiments ◽  
Management Strategies ◽  
Cotton Production ◽  
Cotton Lint ◽  
Insect Management ◽  
Heat Units ◽  
Mechanical Removal ◽  
Four Levels ◽  
Production Areas ◽  
The Impact

In developing management strategies for hemipteran pests in cotton (Gossypium hirsutum L.), it is important to understand the potential of plants to compensate for loss of the fruiting structures. Because of its northern latitude, Virginia has fewer available heat units relative to other cotton-producing states. Therefore, there may be limited opportunity for compensation relative to more southerly production areas. Previous work in Virginia demonstrated that cotton can sustain relatively high levels of first position square loss with no yield loss. This study evaluated the impact of a single event loss of 10–14-d-old bolls via mechanical removal on cotton lint yields with the premise that boll loss would have greater impact than square loss as less time and fewer heat units are available for compensation. Field experiments examining four levels of boll removal (0, 5,15 and 20%) were conducted in 2001,2002 and 2003. Each boll removal level was imposed at three different dates, beginning 2 wks after first flower and at 3- to 5-d intervals thereafter. Yields ranged from 1103–1422 in 2001, 909–1124 in 2002, and 843–1015 kg lint per ha in 2003. There were no significant differences in lint yields among the boll removal dates or removal levels. The results of our study showed that cotton in Virginia, which approaches the northernmost latitude for cotton production, is capable of sustaining losses as high as 20% of 10–14-d-old bolls at a single removal event without affecting lint yield. Results were consistent despite the wide variation in rainfall and temperatures during the 3 study years.

Herbivory, Seed Priming, and Tillage Systems: Impacts on the Growth Response of Pisum sativum L.

1998 ◽  
Vol 33 (2) ◽  
pp. 196-211 ◽  
Author(s):  
Livy Williams ◽  
D. J. Schotzko ◽  
L. E. O'Keeffe
Keyword(s):  
Pisum Sativum ◽  
Growth Response ◽  
Field Experiments ◽  
Conservation Tillage ◽  
Seed Priming ◽  
Soil Conditions ◽  
Tillage Practices ◽  
Pisum Sativum L ◽  
Four Levels ◽  
Peg 8000

Field experiments were conducted to determine the effects of herbivory, seed priming, and tillage practices on the growth response of Pisum sativum L. A factorial treatment design incorporated two levels of tillage treatment (moldboard and chisel plow), three levels of seed priming [Captan, PEG (polyethylene glycol) 8000, and Captan+PEG 8000], and four levels of herbivory by Sitona lineatus (L.) (caged controls, uncaged controls, 1 weevil/plant, and 8 weevils/plant). Pisum sativum stands at approximately 75% emergence were infested for 1 wk. Sitona lineatus infestations resulted in defoliation of approximately 5, 25, and 55% for the control, low, and high weevil densities, respectively. Conservation tillage led to increased surface residue but did not affect soil moisture, temperature, or compensatory growth response of P. sativum. Seed priming treatments, incorporating PEG, led to an undercompensatory growth response of P. sativum, as did high levels of S. lineatus defoliation. Improved seed priming methods that promote vigorous seedling growth may help minimize the impacts of S. lineatus and suboptimal soil conditions on P. sativum.

Tillage and Nitrogen Influence Weed Population Dynamics in Barley (Hordeum vulgare)

1997 ◽  
Vol 11 (3) ◽  
pp. 502-509 ◽  
Author(s):  
John T. O'Donovan ◽  
David W. McAndrew ◽  
A. Gordon Thomas
Keyword(s):  
Population Dynamics ◽  
Field Experiments ◽  
Soil Surface ◽  
Conventional Tillage ◽  
Zero Tillage ◽  
Tillage Systems ◽  
Green Foxtail ◽  
Field Pennycress ◽  
Soil Seedbank ◽  
Four Levels

Field experiments were initiated at Alliance and Hairy Hill, Alberta, in 1989 to investigate the effects of conventional tillage, zero tillage, and four levels of nitrogen fertilizer on continuous barley production. In both tillage systems, the nitrogen was banded 6 to 8 cm deep between alternate barley rows. Herbicides were used for weed control each year. The influence of tillage and nitrogen on weed seed population dynamics was determined in 1991 and 1992. In the zero-tillage system, a large proportion of the weed seeds were present either at the soil surface or at the 5- to 10-cm depth. Green foxtail, the dominant species at Alliance, was also present at Hairy Hill where field pennycress was dominant. Green foxtail was consistently associated with low (residual) nitrogen and, in most cases, with conventional tillage. At both locations, green foxtail populations tended to decrease to very low levels as nitrogen rate increased, especially in zero tillage. At Hairy Hill, field pennycress populations in the soil seedbank were higher in zero tillage compared with conventional tillage, but plants that emerged from the soil seedbank in the field in spring were lower in zero tillage. Field pennycress populations were highest under low nitrogen. The results indicate that banding nitrogen has the potential to be an effective tool for green foxtail and field pennycress management in conventional- and zero-tillage systems, resulting in less dependence on herbicides for their control.

Influence of NAA and nitrogen on the growth and yield of late-planted paddy (Oryza sativa L.)

1986 ◽  
Vol 106 (1) ◽  
pp. 37-40
Author(s):  
H. S. Grewal ◽  
H. S. Gill
Keyword(s):  
Grain Yield ◽  
Field Experiments ◽  
Foliar Application ◽  
Oryza Sativa L ◽  
Foliar Spray ◽  
Growth And Yield ◽  
Naphthalene Acetic Acid ◽  
Water Spray ◽  
Area Index ◽  
Four Levels

SUMMARYField experiments were carried out at Ludhiana in Punjab during 1982 and 1983 on the effect of foliar application of water spray or naphthalene acetic acid (NAA) at 100 and 200 mg/1 of water on the growth and yield of rice when applied at tillering and before panicle emergence stages of late-transplanted paddy grown under four levels of nitrogen (0, 60, 90 and 120 kg/ha). Foliar spray of NAA significantly increased the grain yield of paddy as compared with water spray under low levels of nitrogen (0 and 60 kg/ha) owing to increases in the number of ear-bearing shoots per plant, number of filled grains per panicle and grain weight. Chlorophyll content of leaves, leaf area index and interception of photosynthetically active radiation by the crop canopy also increased with foliar spray of NAA and application of nitrogen. Paddy responded significantly up to 90 kg N/ha in terms of grain yield whereas straw yield increased significantly up to 120 kg N/ha. However, grain mass declined significantly with increase in nitrogen from 90 to 120 kg/ha.

scholarly journals Influence of N and P fertilizer application on root growth, leaf photosynthesis and yield performance of groundnut

2008 ◽  
Vol 32 (3) ◽  
pp. 369-374 ◽  
Author(s):  
M Altab Hossain ◽  
A Hamid
Keyword(s):  
Root Growth ◽  
Field Experiments ◽  
Block Design ◽  
Fertilizer Application ◽  
Silty Clay ◽  
Leaf Photosynthesis ◽  
Pod Yield ◽  
P Fertilizer ◽  
Four Levels ◽  
Set Up

Field experiments were carried out at the Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur during 2000-2002 to evaluate the effect of N and P applicaiton on the root growth, leaf photosynthesis and yield of groundnut (var. Basantibadam). Four levels of N (0, 20, 40 and 60 kg N/ha) and four levels of P (0, 13, 26 and 39 kg P/ha) were the treatment variables. The trial was set up in a randomized complete block design under factorial arrangement with three replications. Application of N and P fertilizer exerted significant effects on root development, photosynthesis, yield contributing characters and pod yield of the crop. Plant receiving 60 kg N and 39 kg P/ha had larger root system, greater photosynthetic rate and better yield contributing characters that resulted in the maximum pod yield which, however, was not significantly different from N60P26 treatment. Hence, it is recommended that higher yield of Basantibadam can be obtained from N60P26 kg/ha in salna silty clay loam soil of Madhupur tract (AEZ 28) of Bangladesh.DOI: http://dx.doi.org/10.3329/bjar.v32i3.538Bangladesh J. Agril. Res. 32(3) : 369-374, September 2007

Evidence of density-dependent oviposition behaviour byListronotus bonariensis(Coleoptera: Curculionidae) in Canterbury pasture

1998 ◽  
Vol 88 (5) ◽  
pp. 527-536 ◽  
Author(s):  
M.R. McNeill ◽  
D.B. Baird ◽  
S.L. Goldson
Keyword(s):  
Biological Control ◽  
Field Experiments ◽  
Adult Population ◽  
Egg Laying ◽  
Oviposition Behaviour ◽  
Initial Population ◽  
Adult Density ◽  
Control Effort ◽  
Density Dependent ◽  
Age Related

AbstractArgentine stem weevil (Listronotus bonariensis) (Kuschel) is a pasture pest ofLoliumspp. in New Zealand and is the target of a classical biological control programme using the parasitoidMicroctonus hyperodaeLoan. However, laboratory experiments have indicated a strong density-dependent egg laying response which may have important implications for the biological control effort. Two field experiments were conducted using a manipulated range of weevil densities within 2.0–2.4 m–2field enclosures and oviposition activity measured by weekly sampling of grass tillers within the enclosures. In both experiments, density had no effect on general oviposition behaviour although the percentage of tillers found to be infested with eggs increased significantly at higher densities. In experiment 1,L. bonariensisexhibited strong density-dependent oviposition with a significant decline in eggs/tiller/female with increasing adult density. An initial population of fiveL. bonariensism−2oviposited 32 times more eggs/tiller/female than 200L. bonariensism−2. By comparison, density-dependent oviposition was absent in experiment 2 with eggs/tiller/female comparable for all densities. The dramatic difference between the two experiments in the expression of density-dependent oviposition was attributed to prevailing spring temperatures during the sampling interval, which in the second experiment were much cooler and delayed the onset of egg laying. It is probable that in experiment 2, oviposition was not regulated by density-dependent cues but limited by temperature and age related mortality in the adult population. The mechanism for density-dependent oviposition, its occurrence in the field and impact on the effectiveness of the parasitoidM. hyperodaeare discussed.

scholarly journals Synergistic and antagonistic effects of soil applied P and Zn fertilizers on the performance, minerals and heavy metal composition of groundnut

2020 ◽  
Vol 5 (1) ◽  
pp. 1-9
Author(s):  
Christopher Muyiwa Aboyeji ◽  
Oluwagbenga Dunsin ◽  
Aruna Olasekan Adekiya ◽  
Khadijat Omowumi Suleiman ◽  
Chinomnso Chinedum ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Field Experiments ◽  
Growth Parameters ◽  
Synergistic Effects ◽  
Chemical Constituents ◽  
Block Design ◽  
University Teaching ◽  
Nutrient Elements ◽  
Total Biomass ◽  
Four Levels

AbstractNutrients use efficiency of plants could be affected by the antagonistic or synergistic effects of two or more elements in the soil leading to decreased or increased yield. Field experiments were conducted in 2017 and 2018 cropping seasons at the Landmark University Teaching and Research farm, Omu-Aran, Nigeria, to determine the interaction between zinc (Zn) and phosphate (P) fertilizers on growth, yield, nutrient elements and some heavy metals composition of groundnut grown on an Alfisol. Treatments consisted of four levels of phosphorus (0, 40, 80 and 120 kg P ha-1) and three levels of zinc (0, 4 and 8 kg Zn ha-1). The experiment was laid out in a Randomized Complete Block Design (RCBD), replicated four times. The following parameters were taken: plant height, plant spread, total biomass, number of pods/plot, weight of pods/plot, number of seeds/plot, weight of seeds/plot. Laboratory analysis of some chemical constituents of groundnut seed was carried out to determine the nutrient and heavy metals composition. Results indicated that application of 8 kg Zn ha-1 and 120 kg P ha-1 had a synergistic effect on the growth parameters and antagonistic effect on the yield, yield parameters, some nutrient elements and beneficial heavy metals. Application of 8 kg Zn and 80 kg P ha-1 is therefore recommended on an Alfisol without necessarily increasing the concentration of non-beneficial heavy metals in groundnut seed.

scholarly journals Effects of Boron and Molybdenum on the Yield of Chickpea

1970 ◽  
pp. 17-24
Author(s):  
NC Shil ◽  
S Noor ◽  
MA Hossain
Keyword(s):  
Field Experiments ◽  
Flood Plain ◽  
Optimum Dose ◽  
Single Application ◽  
Rabi Season ◽  
Treatment Combination ◽  
Floodplain Soil ◽  
Combined Application ◽  
Four Levels ◽  
Yield Maximization

Field experiments on chickpea (cv. BARI Chola-5) were carried out in Calcareous Dark Grey Floodplain Soil under AEZ 11 at Jessore and Non Calcareous Grey Floodplain Soil under AEZ 13 at Rahmatpur during the rabi season of 2001-2002 and 2002-2003. The objective was to find out the optimum dose of boron and molybdenum for yield maximization. Four levels each of boron (0, 1, 2 and 2.5 kg/ha) and molybdenum (0, 1, 1.5 and 2 kg/ha) along with a blanket dose of N20 P25 K35 S20 Zn2 kg/ha & cowdung 5 t/ha were applied in this study. The combination of B2.5 Mo1.5 kg/ha and B2.5 Mo1 kg/ha produced significantly higher yield in both the years of study at Jessore and Rahmatpur, respectively. The said treatments produced the highest mean yields of 2.10 and 1.49 t/ha for Jessore and Rahmatpur, respectively, which was around 53% higher over control (B0 M0). The combined application of both boron and molybdenum were found superior to their single application even though boron played major role in augmenting the yield. However, from the regression analysis, the optimum treatment combination was calculated as B2.34 Mo1.44 kg/ha for Jessore and B2.20 Mo1.29 kg/ha for Rahmatpur. Key words: Boron, molybdenum, chickpea, yield, flood plain soil. DOI = 10.3329/jard.v5i1.1452 J Agric Rural Dev 5(1&2), 17-24, June 2007

Sign in / Sign up

Export Citation Format

Share Document