GHSIM Developed in Spreadsheet Quattro Pro Simulates the Interactive Greenhouse

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 448c-448
Author(s):  
Douglas A. Hopper

A computer model, GHSIM, was formulated in Quattro Pro spreadsheet format. GHSIM was designed having individual pages calculating simulated activities necessary for greenhouse production. Pages were arranged by alphabetical topics starting with the “Area” used in the greenhouse. Time advanced by 1 day for each 10 s of real time. The time advance in the program can be paused to make setting changes interactively. Pest infestation occurred as probabilities accumulated, and the pest population spread through the greenhouse based on proximity and density of pests. Pest control was simulated by a pesticide application capable of partially reducing populations; repeated applications could effectively eliminate a pest. Crop growth was simulated by iterative acccumulation of biomass using Euler integration of daily plant growth. The daily growth increment was calculated using the first derivative of the Richard's Function. Large pest populations negatively impacted the daily growth increment, and pesticide applicaions would remove the inhibition of growth. Additional features proposed include light and temperature effects on the plant growth rate and accumulated biomass.

1985 ◽  
Vol 63 (1) ◽  
pp. 22-27 ◽  
Author(s):  
G. H. Geen ◽  
J. D. Neilson ◽  
M. Bradford

Chinook salmon (Oncorhynchus tshawytscha) eggs, alevins, and fry were reared in pH 4.5, 5.0. 5.5, 6.2 (control), and 7.0 water from the eyed stage of development. Survival through hatching was >90% in all instances. Alevin mortality was high at pH 4.5 and 5.0. Fry were more tolerant of low pH than alevins. Growth rates of alevins and fry held at or above pH 5.0 and 4.5, respectively, were not affected by pH, nor did exposure to acidic water retard otolith development or result in their resorption. One otolith daily growth increment was formed every 24 h in alevins and fry irrespective of pH. Widths of otolith daily growth increments decreased when fry were transferred to pH 4.5 water and increased on their return to higher pH indicating changes in growth rate. Transfer of fry from pH 6.2 to pH 5.0 or 5.5 had no effect on increment widths.


1997 ◽  
Vol 48 (8) ◽  
pp. 791 ◽  
Author(s):  
Hirokazu Matsuda ◽  
Takashi Yamakawa

The effects of temperature on growth of phyllosomas of the Japanese spiny lobster Panulirus japonicus were investigated. Phyllosomas were individually reared at four temperatures (20°, 22°, 24° and 26°C), and intermoult period and moult increment were monitored. The improved Bêlehrádek’s equation, G = aLb (T–α)c(β–T)d, was used to describe the relationship between growth characters (G: intermoult period, moult increment or daily growth increment), body length (L) and temperature (T), with a and b being constants that change at 17·8 mm body length, c and d being common constants for all sizes, and α and β being the conceptual biological lower and upper critical temperatures, which are variables with body length. The intermoult period increased and the moult increment decreased with decreasing temperature. However, a negative influence on both the intermoult period and the moult increment was observed at 26°C for medium-sized and large phyllosomas. The largest daily growth increment was obtained at 26°C up to 15·0 mm body length, and then at 24°C. This indicates that the optimum temperature for growth decreases from 26° to 24°C at 15·0 mm body length. This optimum temperature for growth seemed to be optimal for survival.


1968 ◽  
Vol 42 (S2) ◽  
pp. 64-80 ◽  
Author(s):  
Giorgio Pannella ◽  
Copeland Macclintock

Tidal cycles are reflected in daily growth-increment sequences in shells of many Recent and fossil mollusks. Living specimens of the bivalve Mercenaria mercenaria were notched at the growing edge of the shell and planted intertidally in Barnstable Harbor, Massachusetts. Shells from two lots, killed at intervals of 368 and 723 days after planting, show the same number of small growth increments as there were days from notching to killing. Superimposed on daily growth record are effects of winter (thin daily increments) and tides (14-day cycles of thick and thin daily increments). Comparison of Barnstable tide record with the first year's growth shows that, for each 14-day cycle, thin daily increments form during neap tides and thicker daily increments form during spring tides. Although tidal patterns are present in subtidal Mercenaria shells, they are rarely as pronounced as in intertidal ones. Spawning patterns differ from winter patterns; they are expressed in the shell by an interruption of regular deposition followed by a series of thin daily increments. Continuous sequences of bidaily patterns, one thick daily increment followed by a relatively thin one, are common in M. mercenaria.The clearest 14-day cycles of deposition were seen in shells of the bivalve Tridacna squamosa. Each daily neap-tide increment is a simple layer consisting of a dark and light zone. Each daily spring-tide increment is a complex layer consisting of two light-dark alternations separated by a depositional break that is more pronounced than the breaks delimiting daily intervals. Preliminary results of growth-increment counts in fossils show a generally decreasing trend of the mean values of days per lunar month toward the Recent. The Pennsylvanian value is 30.07 ± 0.08, a figure that is in general agreement with those of Scrutton (1964), who counted 30.59 days per month on Devonian corals, and Barker (1966), who reported more than 30 days per month in Pennsylvanian bivalves.


2000 ◽  
Vol 18 (2) ◽  
pp. 93-98 ◽  
Author(s):  
R.L. Hummel ◽  
S. Kuo ◽  
D. Winters ◽  
E.J. Jellum

Abstract Utilization of fish waste for producing fishwaste compost (FWC) as a value-added product is preferred to disposing of it in ocean dumping or landfills. This study determined: (i) the effectiveness of FWC as a container-growth medium and N source for greenhouse production of marigolds (Tagetes patula L. ‘Queen Sophia’) and geraniums (Pelargonium x hortorum L.H. Bailey ‘Sprinter Scarlet’) that were drip-irrigated to prevent leaching; and (ii) if leaching was necessary to sustain plant growth. In a 3 by 3 factorial experiment, plants were grown in 100% FWC, 50% FWC:50% Douglas-fir bark (B), and 100% B at 0, 160, and 320 mg (0, 0.0056, 0.0112 oz) N container−1 applied as NH4NO3 every 2 weeks. Under drip irrigation, FWC in the 100% FWC growing medium supplied a sufficient amount of available N up to 7 weeks after transplanting to produce plant quality, shoot growth index (SGI), and shoot and root dry weights comparable to those treated with 320 mg N container−1. In the 50% FWC: 50% B growing medium fertilization with 320 mg N improved plant growth and quality 7 weeks after transplanting. The concentration of inorganic N (NO3 plus NH4) in the 100% FWC declined to very low levels 7 weeks after transplanting. This indicated that FWC used as the sole component of the growing medium was an effective N source for marigolds and geraniums up to 7 weeks after transplant. Compared with no leach plants, irrigation of 100% FWC marigolds with a weekly leaching fraction of about 0.55 did not affect quality, SGI, and shoot dry weight at the time-of-sale, 7 weeks after transplant. The FWC did not have sufficiently high salt content to require minimum leaching to prevent salt injury to the plants.


2018 ◽  
Vol 28 (3) ◽  
pp. 370-377 ◽  
Author(s):  
Nicholas J. Flax ◽  
Christopher J. Currey ◽  
James A. Schrader ◽  
David Grewell ◽  
William R. Graves

We evaluated the effects of seven types of 4.5-inch top-diameter biocontainers and five rates of paclobutrazol drench on the growth and development of angelonia (Angelonia angustifolia ‘Serena White’) and petunia (Petunia ×hybrida ‘Wave® Purple Improved Prostrate’) during greenhouse production. The container types included were biopolyurethane-coated paper fiber; uncoated paper fiber; rice hull; coconut coir; peat; two types of bioplastic container, one made from 90% polylactic acid (PLA) and 10% lignin [PLA-lignin (90/10 by weight)] and another made from 60% PLA and 40% soy polymer with adipic anhydride {SP.A [PLA-SP.A]; (60/40 by weight)}; and a petroleum-based plastic control. All containers were filled with 590 mL of substrate composed of (by vol) 75% canadian sphagnum moss and 25% perlite. Ten days after transplanting seedlings, 2-fl oz aliquots of deionized water containing 0, 1, 2.5, 5, 10, or 20 mg·L−1 paclobutrazol were applied to the substrate surface as drenches. The date of anthesis was recorded for each plant, and growth data were collected 6 weeks after transplant. Shoots were harvested and dried and shoot dry weight (SDW) was recorded. Height (angelonia only) and diameter of angelonia and petunia and time to flower were calculated. Container type and paclobutrazol concentration interacted to affect size and SDW of angelonia and petunia. Growth index of angelonia treated with 0 mg·L−1 paclobutrazol and grown in coir and peat containers was 19% to 29% and 29% to 38% smaller than that of plants in other container types, respectively. Diameter of untreated petunia grown in peat containers was similar to that of those grown in coir and uncoated paper fiber containers, but was smaller (10.9 to 13.5 cm) than that of plants grown in other container types. As paclobutrazol concentrations increased from 0 to 20 mg·L−1 treatments, SDWs of petunia grown in coir containers were suppressed by 23%, whereas plants grown in rice hull containers were up to 45% less. Our results indicate that growth suppression of angelonia and petunia grown in biocontainers using paclobutrazol drenches varies by the type of biocontainer. Producers should reduce paclobutrazol drench concentrations to produce plants of appropriate size if substituting coir or peat biocontainers for traditional petroleum plastics, whereas no adjustment in plant growth retardant (PGR) drench concentrations is required for plants produced in the other biocontainer types we evaluated.


2021 ◽  
Vol 8 (4) ◽  
pp. 104-110
Author(s):  
Di Barbaro Gabriela ◽  
Andrada Horacio ◽  
Batallan Morales Silvana ◽  
Espeche Acosta Eliana ◽  
Rizo Melisa ◽  
...  

To determine the effect of Azospirillum brasilense and soil mycorrhizal fungi on the nutrition of the Jerusalem artichoke crop (Helianthus tuberosus L.), evaluations of agronomic parameters and the health status of the plants were carried out, under greenhouse conditions. The tests were carried out, at the moment of the implantation of the culture: the tubers were inoculated with A. brasilense and with native mycorrhizal fungi, generating four treatments including the control and the co-inoculation of the consortium of the microorganisms under study (T0: control or control without inoculation; T1: inoculation with native A. brasilense; T2: inoculation with native mycorrhizal fungi and T3: joint inoculation with A. brasilense and native mycorrhizal fungi. The results indicate that co-inoculation with A. brasilense and with native mycorrhizal fungi increased plant growth in height, leaf area, biomass, dry matter, and yields significantly in greenhouse production. It was determined that the application of the selected microorganisms has a plant growth-promoting effect, increasing the productivity of cultivated topinambur in the greenhouse


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