Browsing by Author "Moore, Frank D., III, advisor"
Now showing 1 - 11 of 11
Results Per Page
Sort Options
Item Open Access Carbon dioxide in the tomato plant microenvironment(Colorado State University. Libraries, 1978) McCoy, Phoebe A., author; Moore, Frank D., III, advisor; Basham, Charles W., committee member; Danielson, Robert E., committee memberPaper and polyethylene mulches have proven effective in causing increased growth and yields of several field-grown vegetable crops. These increases cannot always be attributed entirely to temperature and moisture differences resulting from mulching. This indicates that another environmental factor, perhaps CO2, could be partially responsible. Carbon dioxide enrichment has met with great success in greenhouses. A slight CO2 enrichment effect could result from the trapping of diffusing CO2 by a mulch and its subsequent release directly around plants growing outdoors. The relationship among polyethylene-coated black paper mulch, CO2 in the plant microenvironment, and subsequent plant growth and yield was studied. Spring Giant Hybrid tomato seedlings were transplanted into mulched and unmulched beds in the field. Similar soil moisture levels were maintained through separate drip irrigation systems for mulched and unmulched plots. Temperatures were monitored relative to both treatments and found not significantly different at a 5 cm depth in the soil or at a 30 cm height in the canopy. Gas samples were collected from within the plant canopy at 3-hour intervals over two 24-hour periods. The CO2 concentration at the base of the plants (1 cm) was greater in the mulched plots in both the light and the dark while the CO2 level over the entire 34 cm profile was greater above the mulch in the dark. Carbon dioxide levels in the soil under the mulch and between the mulch and soil surface were greater relative to the bare soil. Plant tis sue dry weights were greater by 18% in the mulched plots. Total marketable fruit yield per plant was increased 36% and a 23% increase in weight per fruit was noted in the mulched plots. The increased plant growth and fruit yields were attributed to elevated levels of CO2 occurring in the mulched plant microenvironment.Item Open Access Carbon dioxide levels in the plant microenvironment as influenced by a poly-coated paper mulch(Colorado State University. Libraries, 1983) Tarter, Cheryl K., author; Moore, Frank D., III, advisor; Wallner, Stephen J., committee member; Smith, D. D., committee memberEffectiveness of carbon dioxide (CO2) enrichment using a polyethylene coated black paper mulch, incorporated nitrogen and wheat straw particles, and field CO2 release was investigated. A mulch covering or mulch over incorporated plant residue, such as straw, has been suggested as a possible means of CO2 enrichment which results from trapping the CO2 evolved from the soil. This idea was tested using Great Lakes Mesa 659 lettuce seedlings in growth chambers and in an outdoor setting. Carbon dioxide concentrations at the base of the plants and at a 5 cm depth in the root zone were greater in mulched and mulched straw treatments. Non-mulched straw did not increase surface CO2 concentrations. Growth of mulched plants in the chambers was approximately 80% greater than that of non-mulched plants. Mulched plants in the outdoor study had a growth increase of about 13% when compared to non-mulched plants. Increases in growth of mulched plants were attributed to greater CO2 levels, since soil moisture levels and temperatures were similar in all treatments. Straw suppressed growth and would not be recommended as a CO2 source. Mulch applied over CO2 release lines in the field was found to be an effective means of CO2 enrichment of a lettuce canopy by creating a physical barrier to rapid air exchange, thereby concentrating released CO2 under the mulch. Mulch over a release line more than tripled CO2 concentrations near the soil surface when compared to CO2 release with no mulch covering or CO2 supplement. Significant enrichment levels were maintained to 25 cm above the soil surface on still days by means of a mulched CO2 release line. Subsurface CO2 concentrations were increased by the application of mulch and averaged 857 ppm which was considered non-phytotoxic. The effect on soil CO2 levels from the release line was negligible. Inconclusive results in plant response suggest further study is warranted.Item Open Access Determination of optimum storage conditions for orthodox seeds(Colorado State University. Libraries, 2000) Fang, Jian, author; Moore, Frank D., III, advisor; Roos, Eric E., advisorTo view the abstract, please see the full text of the document.Item Open Access Drought stress by growth stage and onion plant growth(Colorado State University. Libraries, 1984) Richwine, Paul Allen, author; Moore, Frank D., III, advisor; Danielson, Robert E., committee member; Wallner, Stephen J., committee memberThree distinct growth stages of the onion's vegetative development have been defined: early (73-101 days), mid (102-122 days), and late season (123-143 days). Two years of field experiments and a greenhouse study with onions examined the effects of drought stress applied during these stages. Influence of excessive nitrate salts was also investigated. Rootview boxes submerged in a furrow-irrigated onion field allowed for a continuous study of root, leaf, and bulb development. A drought stress of -100 kPa soil matric potential was imposed for three weeks during each growth stage. Soil matric potential of -55 kPa was used as a standard. Onion plants located in the greenhouse were hydroponically grown in cans containing half-strength Hoagland's solution. Polyethylene glycol (PEG 3500) was used as the osmotic potential modifier creating drought stresses of -100 kPa and -200 kPa which were applied for 3 weeks during each growth stage. Ammonium nitrate (NH4NO3) at levels of 153 and 202 ppm NO3-N provided the high nitrate source. Both field and greenhouse studies identified the mid-season growth stage as the most sensitive to drought stress equal to or greater than -100 kPa. Bulb, root, and top components were significantly reduced as compared with the no stress treatment. Drought stress of -100 kPa during the early season growth stage had no significant negative effect on onion growth, however, a drought stress of -200 kPa applied during the early season growth stage caused growth to be suppressed. Drought stress had no significant effect on onion growth when applied during the late season growth stage. There was no significant influence of high nitrate levels on onion top, bulb, or root growth.Item Open Access Individual seed electrolyte leakage tests and evaluation of soaking injury using maize(Colorado State University. Libraries, 1993) Davidson, Kimberly V., author; Moore, Frank D., III, advisor; Ross, Cleon W., committee member; Stushnoff, Cecil, committee member; Roos, Eric E., committee memberDetermination of seed viability has traditionally involved germination, which is obviously destructive to the seed and also labor intensive. Both are far from being cost effective. The development of non-destructive or at least less injurious methods of testing seed quality i.e. viability and vigor determination using electroconductivity measurements of single seed leachate solutions could effectively replace the standard germination test. The objectives were to compare five indices of seed quality, all of which are based on individual seed leachate conductivity tests. Additionally, if the soak period is brief enough, there should be little injury to the seeds allowing for successive soaks on the same sample. Seeds of Zea mays L. were aged using two methods to obtain varying levels of viability and vigor for comparisons. The first method, modified controlled deterioration, involved placing two samples of seeds in separate desiccators over a saturated NaCl solution for 16 and 20 days for seed lots 88-2i and 88-1d, respectively. The seeds were sealed in aluminum foil packets, 110 per packet, and aged for 120 hours at 45°C. The second method involved placing two samples of seeds in separate desiccators over H2SO4 at 35°C for 238 and 484 days, respectively for desiccators one and two. After aging, seeds from each desiccator were kept in aluminum foil packets. Electroconductivity testing was done on samples of 100 seeds from each of the aging methods. The seed samples were soaked for six hours during which time 29 scans of data were obtained. The samples were dried at room temperature for seven days after which time they were germinated using the rolled paper towel method. An additional 100 unsoaked (control) seeds were germinated at the same time. Radicle lengths were measured at the end of 72 hours and final germination was counted at the end of seven days. Relative vigor was calculated as a ratio of the soaked seed radicle lengths divided by the unsoaked control seed radicle lengths. Electroconductivity data were concatenated and made compatible with the UNIX format. Five indices were derived from the data for determination of their ability to predict maize seed quality. Internal Slope (IS) and mean and median μAmps after five hours of imbibition were derived from a Richards function program, the Initial Leach Rate (ILR) was derived from the rectangular hyperbola and the Average Absolute Leach Rate (AALR) was derived from another Richards function program. The second aging method did not produce the desired range of seed quality and so the results discussed are based on the first aging technique. Internal Slope was the best predictor of seed viability, r2 = 0.91, followed very closely by the median μAmp value, r2 = 0.87, and the mean μAmp value, r2 = 0.81. The ILR and AALR indices did not predict seed quality with r2 values of 0.01 and 0.03, respectively. Relative vigor was not estimated as well as viability, probably due to the artificial aging. A second experiment was designed to study the effect of five successive soak cycles (C) and five cycle durations (CD) of 2, 4, 6, 7 and 8 hours on viability and vigor loss response. All subsets regression plus consideration between bias and random error led to the choice of the following two best subset models: YVIA = 99.14 - 0.0609 (CD*C2), R2 = 0.62, and YRV = 0.99 + 0.0229 (CD) - 0.0101 (CD*C), R2 = 0.52. Response surfaces were generated which suggested that 4 C of 5 hours each resulted in only an 8% loss of viability but a 20% loss of relative vigor. Conductivity measurements taken at the end of each CD for each C showed that 45% of the readily leachable electrolytes leached during the first soak period. Furthermore, a priming effect, invigoration, was observed when the seeds were soaked for a total of ten hours, taking into consideration both the number of cycles and the duration of each cycle.Item Open Access Lettuce irrigation scheduling using atmometers and computers(Colorado State University. Libraries, 1980) McSay, Ann Emery, author; Moore, Frank D., III, advisor; Workman, Milton, committee member; Angleton, George, committee member; Danielson, Robert E., committee memberLinear relationships between soil matric potential (SMP) and evaporative power of the air (EPA) were developed in order to schedule irrigation of lettuce in arid or semi-arid regions. The irrigation scheduling model is based on the assumption that SMP i.e. soil moisture "need" is a function of stage of growth, EPA, soil texture and root zone recharge. Root zone recharge may be due to an irrigation which brings the effective root zone to field capacity or a rainfall event which accomplishes the same purpose. Four linear equations similar to stage of growth coefficients are modified by soil coefficients which account for variation in hydraulic conductivities due to soil texture. Information required on a daily basis for daily output consists of milliliters of water lost from standardized Bellani plant atmometers and inches of rainfall from 8 inch diameter USWS rain gauges. The irrigation scheduling output is in 2 forms. One is graphic. Graphic analysis allows the user to visualize the progression of SMP (converted from ƩEPA) as a function of days from last recharge. The observer simply compares this plotted line to the SMP horizontal (constant) line, one for each of the 4 growth stages. An obvious reminder of tardiness occurs after the two lines intersect. This graphic form of output results from a program written in assembly language for a programmable calculator. The other form of output is digital. A FORTRAN program for a large scale computer was written. The program fits, by the least squares method; linear, quadratic and cubic regression equations to ƩEPA versus days from last recharge data. The program solves each of the 3 polynomials for days to next recharge and converts the end of the interval to a calendar date. The user then selects the most imminent of the 3 predicted dates with the aid of associated coefficients of determination. A tardiness reminder is also provided. The program is used in the interactive mode and will permit rapid daily update and query of 400 different plantings. A method was developed to protect the Bellani plate assemblies from freezing.Item Open Access Nitrification suppression and provitamin A content of spinach(Colorado State University. Libraries, 1977) Holbrook, Timothy B., author; Moore, Frank D., III, advisor; Basham, Charles W., committee member; Johnson, Gestur, committee member; Sabey, Burns R., committee memberBloomsdale Longstanding' spinach was grown in the field and in growth chambers to determine the effect of soil NH4 and soil NO3 on spinach yield, green color, leaf NO3, and provitamin A (carotene) content. Nitrapyrin (Np) was adsorbed onto (NH4)2SO4 crystals and applied as a band in the field and blended with a soil-perlite mix in the growth chambers. Field treatments received (NH4)2SO4 fertilizer at 90 kg N/ha and differed only by the addition of 140 g/ha (0.0625 ppm soil basis or 0.156% based on N) Np to one treatment. Significant increases in yield, green color, and carotene content were noted for the Np treatment in the field and attributed to increased soil N retention. A green color difference between treatments with and without Np in the field, as measured by a reflectance meter, of 0.05 relative units correspond with a 15% increase in carotene content for the Np treatment. Carotene yield (kg carotene/ha) of the Np treatment was 43% greater than from the same treatment without Np. Growth chamber treatments varied soil NH4 -N and NO3 -N concentration while maintaining equal fertilizer N applications to expose spinach to a range of NH4/NO3 ratios in a nonleaching system. Fertilizers for the four growth chamber treatments supplied equal amounts of N (400 mg N/2 kg soil mix) for each and were (NH4)2SO4, protected with Np and unprotected, Ca(NO3)2, and a mix of protected (NH4)2SO4) and Ca(NO3)2 to provide a 0.33 NH4 -N/NO3 -N ratio. Np rate was 3 mg/2 kg soil mix or 0.75% based on N. Ammonium toxicity symptoms and greenest co lor were noted for spinach grown with essentially all NH4 -N. Spinach receiving (NH4)2SO4 as sole N source with or without Np, produced statistically equal as well as the greatest amount of carotene. A 48% increase in carotene yield of spinach resulted when NH4 was the available source of N compared to NO3. Large differences in leaf carotene correspond to small differences in leaf color in spinach. Proper manipulation of the soil NH4/NO3 ratio by means of nitrification suppression can increase spinach yield and provitamin A content as well as improve green color with lower leaf nitrate thus bettering consumer acceptability.Item Open Access Nitrification suppression and spinach growth in alkaline soil(Colorado State University. Libraries, 1976) Riggert, Craig E., author; Moore, Frank D., III, advisor; Basham, Charles W., committee member; Soltanpour, Parviz N., committee memberA single at-planting application of (NH4)2SO4 with and without nitrapyrin, [2-chloro-6-(trichloromethyl) pyridine], was evaluated on spinach in alkaline soil in 2 field experiments and 1 greenhouse experiment. Parameters measured were soil NH4 -N and NO3 -N, spinach yield, leaf color and leaf P, Fe and Zn. Nitrapyrin was adsorbed onto (NH4)2SO4 crystals then applied in a band at planting in the field experiments. The first field experiment consisted of N application rates of 87. 8 and 157.5 kg/ha and nitrapyrin rates of 0, 280 and 560 g/ha while the second field experiment included N application rates of 0, 45 and 90 kg/ha and nitrapyrin rates of 0, 140, 280 and 420 g/ha. Nitrapyrin (1.5 ppm - dry soil weight basis) was adsorbed onto (NH4)2SO4 crystals and incorporated with soil in the greenhouse at N rates of 0, 400 and 800 mg/2 kg dry soil. Drainage was prevented in this greenhouse experiment. Spinach yields were measured and leaf and soil samples were taken at harvest from the first field experiment and the greenhouse experiment. Yields were measured and leaf and soil samples were taken 28, 42, 48 and 56 days from planting in the second field experiment. Apparently little leaching occurred in the first field experiment and final yield was greatest when N applications included 280 g nitrapyrin/ha. This resulted in high soil concentrations of both NH4 and NO3 at harvest. Concentrated soil NH4 resulting from prolonged nitrification suppression with as much as 560 g nitrapyrin/ha produced good plant growth on this alkaline soil. Leaching had apparently occurred in the second field experiment and increased yields with nitrapyrin 56 days from planting were attributed to increased soil N retention. Prolonged nitrification suppression from 1.5 ppm nitrapyrin in the greenhouse resulted in severely stunted plant growth along with other NH4 toxicity symptoms. Leaf color, which is important in determining market and nutritional quality of spinach, was darker green when (NH4)2SO4 adsorbed with nitrapyrin was applied. This was measured during all 3 experiments. The dark green leaf color was measured and/or observed well before observed yield differences. Leaf P, Fe and Zn concentrations were generally increased when NH4 applications included nitrapyrin in this study. Leaf P concentrations increased the most while leaf Zn concentrations increased the least. Increase in leaf P, Fe and Zn concentrations due to the addition of small amounts of nitrapyrin to NH4 fertilizer may be an important consideration with regard to alkaline soils where P, Fe and Zn are often limiting.Item Open Access Onion growth and water use patterns in relation to drought stress(Colorado State University. Libraries, 1983) Bosley, Donald Bruce, author; Wallner, Stephen J., advisor; Moore, Frank D., III, advisor; Reid, C. P. P., committee member; Danielson, Robert E., committee memberFour distinct growth stages of storage onions were established using growth analysis techniques; stand establishment (0 - 4 leaves), leafing (4 - 8 leaves), bulbing (8 - 10 leaves), and sizing (less than 10 leaves. Visible developmental observations such as number of functional leaves were determined to be the best indicator of crop growth stage. Linear relationships between soil matric potential (SMP) and evaporative demand (ED) were developed for each of the latter three growth stages in order to determine proper irrigation timing. It was assumed that SMP i.e. soil moisture "need" is a function of stage of growth, EPA, soil texture and root zone recharge. It was determined that to limit SMP to no greater than -40 kilopascals (kPa), irrigation or a significant rainfall should occur at or before 789 ml of water are evaporated from a black Bellani plate atmometer during the leafing growth stage. In a like manner, soil recharge should occur at or before 340 ml are evaporated during the bulbing and sizing growth stages. Onions were stressed during the leafing, bulbing, and sizing growth stages by withholding irrigation until a soil matric potential of -70 kilopascals was reached. No significant differences were observed in either the growth pattern or final yield between each stress treatment and the unstressed control. Hydroponically grown onions were transplanted into containers located in a greenhouse so that roots were subjected to six different levels of polyethylene glycol (PEG) 3500 osmotic solutions for five weeks. Leaf, bulb, and root dry weights were found to be significantly reduced in the treatment of -274 kPa or more negative osmotic potential than treatments of -147 kPa or less negative potential. Root:shoot ratio was found to be significantly greater in only one instance. After three weeks of growth the highest stress level (-622 kPa) resulted in the largest root:shoot ratio. This observation was believed to result from aproportionately greater leaf tissue decline than root tissue decline in response to high osmotic stress.Item Open Access Relation of elevation to potato growth and propagule productivity(Colorado State University. Libraries, 1977) Hartz, Timothy K., author; Moore, Frank D., III, advisor; Workman, Milton, committee member; Knutson, Ken, committee member; Cuany, Robin, committee memberTo document the effects of the high altitude environment on the growth and development of the potato (S. tuberosum), plants of cv. Kennebec were grown at sites ranging from 1533 to 3213 m. Temperature and light were the environmental parameters of primary interest and the experiment was designed to eliminate other influences. Since insolation was high at all sites, shade structures were installed to provide a wider range for this factor. Maximum vegetative growth occurred at 2372 m. This site had a mean temperature of 17° C with a wide diurnal range. Above 2800 m, unshaded leaves exhibited a pronounced folding considered to be a response to high light intensity. Tuber fresh weight per plant decreased only slightly with increasing elevation. Shading increased vegetative growth and reduced tuber yield and specific gravity at all elevations. Shading also retarded maturity as evidenced by the consistently higher nitrate content of leaves from shaded plants. Regression analysis indicated that maturity, as measured by tuber specific gravity, was highly correlated with accumulated heat input. Net assimilation and tuber yield were positively correlated with total insolation and a revised measure of heat input designed to compensate for increasing respiratory losses with increasing night temperature. A comparison of site potential is presented. Tubers produced at the various sites were grown in a greenhouse under controlled conditions to determine the effect of the parents' environment on the yield potential of the succeeding generation. Rate of emergence of the progeny increased with increasing elevation of the parent. This earlier emergence was reflected in earlier vegetative growth and tuber initiation which resulted in higher tuber yield early in the season. However, when grown to completion, there was no significant difference in vegetative growth or tuber yield among groups. Photosynthetic rates were determined. The environment of the parent had no influence on the photosynthetic activity of the progeny.Item Open Access Yield response of mulched field grown tomatoes irrigated with carbonated water(Colorado State University. Libraries, 1991) Novero, Ricardo Pegenia, author; Moore, Frank D., III, advisor; Towill, Leigh E., committee member; Shanahan, John F., committee member; Smith, D. D., committee memberHundreds of literature citations report positive responses of crops to CO2 enrichment of greenhouse atmospheres. Carbon dioxide enrichment was done, either by open air fumigation with CO2 gas or irrigation with carbonated water. In the open field where wind movement deters CO2 enrichment, open air fumigation techniques were mostly a failure and the benefits of irrigation with carbonated water to plants has yet to be established. The response of mulched field-grown tomatoes to irrigation with carbonated water using drip irrigation system was studied during 1988 and 1989. Injecting CO2 into the irrigation water decreased water pH and, consequently, lowered soil pH. The decrease in soil pH, which was expected to increase the availability of P, Ca, and metallic elements such as Zn, Fe, and Mn, did not affect the plant uptake of any of the aforementioned elements except for Zn. Zinc concentration in the leaves of CO2 treated plants was higher than that of the control plants for the 1988 experiment. Above ground enrichment at the crop canopy level was evident primarily during irrigation. However, residual soil CO2 was observed for the mulched plots irrigated with carbonated water. Soil CO2 concentrations for the control and carbonated water treated plots were similar under unmulched conditions. Mulching alone increased fruit yield by 8%, and further yield increases ranging from 7 to 23% were attributed to irrigation with carbonated water. The yield component contributing most to increased fruit yield in plots irrigated with carbonated water was fruit size. The observed yield increase for carbonated water irrigated plants was probably due to enhancement of photosynthesis. Plants treated with carbonated water produced fruits with higher soluble solids, a quality factor that may be preferred.