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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Effect of chemical fertilization and organic amaranth (Amaranthus caudatus L.) var. Alegria INIAP Chaltura

Pablo Raúl, Andrade Andrade 01 January 2006 (has links) (PDF)
The present investigation was made in the Experimental Farm "La Pradera", located in the province of Imbabura, the parish of San José de Chaltura, to 1350 meters above sea level and an average temperature of 16, 4⁰ C. To analyze the effect of the chemical and organic fertilization in amaranth of variety INIAP "Alegría" was the primary target of the investigation. The field work was made in a lapse of 6 months. The design of complete blocks (DBCA) with 15 treatments was used at random and three repetitions by treatment. The experimental unit was 18 m². It was evaluated by means of analysis of variance and the Turkey test at 5%. The factors in this study are constituted by the elements N, P, S and organic fertilizer. The analyzed variables were: number of plants; days to the flowering; days to the harvest; height of plants; biomass; extraction of nutrients; and grain yield. The number of plants presented significant difference to 1% for treatments and to 5% for blocks, the treatments that reached the greater number of plants are T11 (80-60-40-0) and T14 (0-0-0-10) with an average of 30 and 29 plants of amaranth in 0.50 linear m respectively. The treatment T4 (120-60-20-0) presented the greater height at 45 days of seedtime, with an average of 24.10 cm. The height of plants at flowering I present significant statistical results highly is the T4 (120-60-20-0) and T5 (160-60-20-0) respectively present values of height of 119.30 and 103.40 centimeters. The height of plants at the harvest determines significant difference for treatments the highest being the T5 (160-60-20-0), the one that reached the greatest height with an average of 148, 11 centimeters. The days to the flowering of the amaranth were between 70 and 85 days from seedtime and the days to the harvest were between 143 and 152 days. The treatment that reached the greater mean efficiency was the T5 (160-60-20-0) with 2583, 69 Kg/ha unlike the control who reached an average of yield of 686, 66 Kg/ha. In the organic treatments the greater yield registry in T15 (0-0-0-15) where 15 tons of organic fertilizer by hectare was used resulting in 1672.59 Kg/ha.
112

The Study of Alfalfa (Medicago Sativa) Production In the Community of El Troje

Penafiel Alvarado, Juan Leopoldo 01 January 1998 (has links) (PDF)
The alfalfa harvest in Ecuador constitutes one of the most important activities, especially as a primary product for animal feeding. The crop is widely distributed in the mountain region of the country. It is important to have studies on the production systems, which facilitate a real and compete vision of those characteristics that interact among them in the agricultural production. With this knowledge it will be possible to look for the most adequate solutions to the conditions of the area where alfalfa is produced. The objectives of the study reported herein were: 1. To make an agricultural, social and economical diagnosis in the community of El Troje, San Luis Parish, Riobamba Canton, Province of Chimborazo. 2. To identify the production system used by the farmers to harvest alfalfa in El Troje community.
113

Technological Processing of the Tomato (Lycopersicum esculentum) and the Project of Industrial Viability

Rico Aranibar, Luis Alberto 01 January 1998 (has links) (PDF)
Technological Processing of the Tomato (Lycopersicum esculentum) and the Project of Industrial Viability by Luis Alberto Rico Arabinar. The present investigation was carried out to determine the aptitude of two varieties of tomatoes in the process of manufacturing concentrations, as well as quantify its loses and performance and evaluate the acceptance and the quality of the product through organoleptic and microbiological analysis. This consists of two parts: First- The laboratory investigation consisted in the elaboration of tomato concentrations. This was done with two varieties, Rio Fuego and Santa Clara, three soluble solid concentrations (10, 20, and 30º brix), and two types of thermal pressure treatment (washing with water at 89º C for 30 minutes and pressure cooking at 110º C for 10 minutes). This was followed by a microbiological analysis, and an organoleptic evaluation of the product. The two tomato varieties were found to adapt as fresh fruit as well as for industry. On the other hand, the organoleptic characteristics of the final product (concentration) presented satisfactory results (5.5/7 points) concerning the test panel; the treatments of 20 brix were the most accepted. The microbiological analysis of the concentration demonstrated the product's sanitary quality. Second-The industrial viability of the project was, in part, carried out while visiting the Omerque Zone and trying to understand its problems of production, commercialization, etc. As well as present a manufacturing presentation of the concentrations in the before said zone. After performing a technical and financial feasibility study, it was determined that the study would prove to be profitable according to VAN (valor actualizado neto) and the TIR (tasa interna de retorno). VAN= $16,717.60 US, TIR= 20.30% (without external financing). VAN= $16,346.80 US, TIR= 25.01% (with external financing). Key Words: Tomato, Concentration, Processing, and Project.
114

Influence of Irrigation Strategies on the Photosynthetic Rate of Syrah

Rodrigues, Daniel Michael 01 June 2010 (has links) (PDF)
Regulated deficit irrigation (RDI) is a common and useful practice for water conservation and improving grape quality. To attain better grape characteristics and wine quality, a substantial degree of irrigation stress is intentionally allowed to occur during the first part of berry formation and can continue until later into veraison. Understanding the effects of deficit irrigation on photosynthetic rates could be helpful in determining at what degree and duration a grower should perform this irrigation practice. The focus of this study was to determine the effects of using differing degrees of RDI in a vineyard located in Paso Robles, California (central coast region) on gas exchange of the Syrah variety. The target irrigation levels were set for each season at 75, 60, 45, and 30% ETc of a fully irrigated vine (100% ET). The 60% replication was considered as the control for this study, as it is the standard target ET rate for the vineyard where this study was conducted. A gas analyzer (LICOR 6200) was used to measure the overall rate of photosynthesis during two successive growing seasons (2004 & 2005). Measurements were taken from bloom through harvest and were compared among the four different irrigation levels. Along with overall photosynthetic rate, the leaf temperature, stomatal conductance, light level, and relative humidity were also measured. The results of the two year study were statistically compared through an analysis of variance (ANOVA) and analyzed for their significance. The results of the study showed that minor differences in the mean photosynthetic rates were found to occur during brief periods of the growing season. These differences ranged from 1-4 weeks and did not occur at similar times of the growing season. However, no statistical significant differences were found to exist when compared among the four irrigation levels for the entire growing season. Observed differences in canopy sizes indicated that irrigation amounts had affected the overall growth to some degree during this two year study. Several plant physiological measurements showed a significant difference in the measured gas exchange rates between sun exposed leaves and the shade leaves within the treatment area. A significant correlation of the effect of leaf temperature on stomatal conductance was observed to exist in one of the irrigation treatments (45% ET) during this study. Other plant physiological measurements indicated that highly significant differences existed between the photosynthesis rate and leaf temperature. Photosynthetic rates were highly significantly correlated to leaf conductance, air temperature, and relative humidity. A significant difference of photosynthetic rates was identified to occur between stomatal conductance and air temperature. This study concludes that differential irrigation amounts on Syrah in the Central Coast region, specifically Paso Robles, have minimal effect on overall photosynthetic rate and does not fully support the anisohydric stomatal reaction that has recently been studied by plant physiologists working with this variety.
115

Elaboration of Noodles, Enriched with Kidney Bean in the Communities of Cuambo and the Rinconada of the Canton Ibarra Province of Imbabura

Meneses, Irma 01 January 2002 (has links)
Currently in Ecuador, the evil and deteriorated nourishment constitutes a serious problem influenced by the high to prevail of malnutrition that each day is aggravated. Therefore it is important to know the adequate utilization of the regional products and new technological alternatives that help to reduce this problem. The accomplished investigation pipe as objective to elaborate noodles craftsmen enriched with kidney bean load fine to contribute to improve the quality protein of the diet in the communities of Cuambo and the Corner; this study was effected after accomplishing a consumption and production diagnosis of foods by the Institute BENSON. The accomplished work understood two phases, one of field and other of investigation; within the first was accomplished the elaboration and noodles tasting through the incorporation to the paste mixture of kidney bean as source of protein and mineral and wheat flour as source of carbohydrates. For the effect was accomplished three classes of noodles with different percentages of matter outweighs (kidney bean beautiful load, wheat flour the baker, egg), salt 1% as taste and sufficient quantity of drinking water for the three types of mixture, accomplished in form artisan. The evaluation of the investigation was effected with the following analysis: organ of the enriched and cooked noodle, application of acceptability surveys to the participants, physical analysis - quimic. The better acceptance treatment by the participants of this investigation was the treatment three, corresponding to the combinations of kidney bean 30%, wheat flour 59%, hen egg 10% and table salt 1% and drinking water the necessary quantity.
116

Comparative study of six different types of subtracts in the production of earthworm humus and its productive effect in vegetables (radish, beet, white onion, cabbage)

Romero Mancero, Romeo Byron 01 January 1999 (has links)
In the province of Chimborazo, found in the Riobamba canton, a study was done with the purpose of comparing different subtracts for the production of earthworm humus (pig feces, guinea pig feces, rabbit feces, bovine feces, market residues, and vegetable residues from the harvest) and its productive effect in vegetables (radish, onion, beet and cabbage). Twenty-four beds, 1.5 m2 (1.5 x 1) in size, as well as sixteen 3 m2 (1 x 3) parcels were used for the study. A design of complete blocks was applied with a monofactorial in the first test, and a bifactorial in the second test. The experiment lasted forty weeks. In general, the best productive behavior by the earthworm humus was distributed among various subtracts. The vegetable residues had the best final weight with a value of 66.75 Kg/parcel. The treatment with guinea pig feces had the best nitrogen content (0.29%). Bovine feces had the best phosphorus content (1.08%). Rabbit feces produced 10.6% of potassium as well as the highest number of earthworms in the harvest (6,900,00). With regards to the production of vegetables, cabbage responded well to almost all of the variables studied. Cabbage obtained superior values than the rest of the vegetables with a 99.5% capture and a 0.25% mortality. The other variables could not be compared because different types of vegetables were used. In the total economic analysis, it was seen that there was a expenditure of 851,960.00 sucres against an income, from the sale of humus and vegetables, of 1,065,000.00 sucres. The net income was 213,120.00 sucres and the benefit/cost was 1.21. It is recommended that this technique be used for small scale production, because the humus improves the ground's physical and chemical characteristics, thus obtaining representative economic gains.
117

Evaluation of 4 small doses of fertilizer in growing maize (Zea mays L.) in two communities of San Juan Ermita, Chiquimula

Villalta Garcia, Victor Estuardo 01 January 2000 (has links)
Corral de Piedra and Salitron are two communities located in the municipality of San Juan Ermita, which is in the department of Chiquimula, Guatemala. In both communities, the land has very sloped topography with slope grades ranging from 12 to 55%. Agriculture is the main production activity with corn (Zea mays L.) and beans (Phaseolus vulgaris) being the crops of greatest economic importance. These crops are planted through a system of sequential association commonly called relay. First, corn is planted at the beginning of the rainy season (May or June). Once it has completed its reproductive cycle, beans are planted in an intercalated fashion between corn plants (Zea mays L.). The harvest of both takes place in December. An important factor in increasing the production of any crop is fertilization. In the above-mentioned communities, the use of commercial fertilizer is common. However, each producer applies only the amount he can afford according to the cost at the market, not the amount the crop actually requires. For this reason, the corn variety ICTA B-1, which can reach yields of 3,250 kg/ha, was evaluated in the experiment. Our objective was to evaluate different doses of fertilizer. The study was done in 1999 during the period when winter is constant (June to September), which is the season when small producers of grain plant their crop. In regard to performance, the dose that responded best was 65-26-0 N-P-K which produced 5,865 kg/ha. In addition, it got a marginal rate of return of Q76.6 per quetzal (Guatemalan currency) invested in increasing the variable costs invested in cultivation. The Institute of Agricultural Science and Technology (ICTA) recommends this dose for the region.
118

OPTIMIZATION OF DOUBLED HAPLOID PRODUCTION IN BURLEY TOBACCO (<em>Nicotiana tabacum</em> L.)

De Oliveira, Ezequiel 01 January 2016 (has links)
Doubled haploidy (DH) is a plant breeding technique that is often utilized by plant breeders to minimize the time required to reach homozygosity in breeding lines. The first objective of this study was to compare two methods of generating DH lines in tobacco (Nicotiana tabacum L.). Inbred burley tobacco varieties TN 90LC and GR 149LC were used to produce both androgenic derived doubled haploids (ADDH) and maternally derived doubled haploids (MDDH). The relative agronomic performance of TN 90LC and GR 149 LC ADDH and MDDH lines was compared when used either as pure-line cultivars or when used for the production of the KT 204LC and TN 97LC hybrid cultivars, respectively. The ADDH method was more efficient than the MDDH method in generating large numbers of haploid plants. On average the ADDH TN 90LC population was statistically inferior to the inbred TN 90LC for several agronomic traits; this inferiority of the ADDH method was not observed in the GR 149LC populations. For both genotypes, the MDDH populations were comparable to the inbred parental genotypes. The ADDH method was inferior for TN 90LC, but several individual TN 90LC ADDH lines were equal or superior to the inbred source. The agronomic variability observed in both ADDH and MDDH lines was decreased when they were used to produce hybrid cultivars. Less variation was observed in the DH-derived hybrids KT 204LC and TN 97LC compared to the ADDH and MDDH TN90LC and GR149LC parental lines, respectively. The significant inferiority of ADDH TN 90 lines in comparison to inbred TN 90LC was not observed in the ADDH derived KT 204 population compared to KT 204LC. The second objective of this study was to compare DH Lines derived from an F1 breeding population versus DH lines derived from a segregating F2 population where plants used for DH were pre-screened for quantitatively inherited resistance to soil-borne diseases black shank (Phytophthora nicotianae) and/or Fusarium wilt (Fusarium oxysporum f. nicotianae). There was a clear difference in susceptibility to black shank between the F1 and F2 derived DH populations, both in terms of average disease incidence, and more importantly, in the percentage of individual lines displaying high disease resistance. For two different burley crosses, DH lines derived from the F1 generation were considerably more susceptible to black shank than DH lines derived from the F2 generation. No differences in the incidence of Fusarium wilt were observed between DH lines of F1 and F2 generations; this was likely due to low overall disease incidence. Although delaying the DH process in tobacco from the F1 to the F2 generation could add time to the development of homozygous breeding lines, the delay may be offset by having to screen fewer finished DH lines to identify superior lines.
119

Map-based Cloning of an Anthracnose Resistance Gene in <i>Medicago truncatula</i>

Yang, Shengming 01 January 2008 (has links)
Anthracnose, caused by the fungal pathogen Colletotrichum trifolii, is one of the most destructive diseases of alfalfa worldwide. Cloning and characterization of the host resistance (R) genes against the pathogen will improve our knowledge of molecular mechanisms underlying host resistance and facilitate the development of resistant alfalfa cultivars. However, the intractable genetic system of cultivated alfalfa, owing to its tetrasomic inheritance and outcrossing nature, limits the ability to carry out genetic analysis in alfalfa. Nonetheless, the model legume Medicago truncatula, a close relative of alfalfa, provides a surrogate for cloning the counterparts of many agronomically important genes in alfalfa. In this study, we used genetic map-based approach to clone RCT1, a host resistance gene against C. trifolii race 1, in M. truncatula. The RCT1 locus was delimited within a physical interval spanning ~200 kilo-bases located on the top of M. truncatula linkage group 4. Complementation tests of three candidate genes on the susceptible alfalfa clones revealed that RCT1 is a member of the Toll-interleukin-1 receptor/nucleotide-binding site/leucine-rich repeat (TIR-NBS-LRR) class of plant R genes and confers broad spectrum anthracnose resistance. Thus, RCT1 offers a novel resource to develop anthracnose-resistant alfalfa cultivars. Furthermore, the cloning of RCT1 also makes a significant contribution to our understanding of host resistance against the fungal genus Colletotrichum.
120

EVALUATING THE EFFECTS OF ORGANIC AND CONVENTIONAL INPUTS ON SOIL CHEMICAL AND BIOLOGICAL PROPERTIES IN A FOUR-YEAR VEGETABLE ROTATION AND THE INVESTIGATION OF SOIL MICROBIAL PROPERTIES ON PLANT GENE EXPRESSION

Law, Audrey 01 January 2009 (has links)
The objective of this research was to determine the effects of conventional inputs on soil chemical and biological properties compared to organic systems in a four year vegetable rotation. Tillage and cover crops were the same in all treatments to avoid confounding factors often present in similar research. Additional experiments investigated plant gene expression in organic and conventional management systems and in soils with decreased microbial diversity. Experimental plots were prepared in the spring of 2004; four replications of three management treatments, organic, low-input and conventional, were arranged in a randomized complete block design. The rotation consisted of edamame soybean, sweet corn, fallow (pastured poultry in organic plots), and potatoes. Soil samples were taken in the spring and fall of each year, along with data for pest damage, weed control, yield and quality. Soil samples were analyzed for enzyme activity (maximum activity under substrate saturation) and basic soil chemical properties. Treatments were compared over time using 2-Way ANOVA. Multiplex terminal-restriction fragment length polymorphism (M-TRFLP) profiles of the soil microbial community were compared using Multiple Response Permutation Procedures (MRPP). Multi-way ANOVA detected significant treatment effects over time in total carbon, nitrogen, Mehlich III K, Exchangeable K and exchangeable Na (p=0.05). Many significant changes in soil properties over time could not be attributed to treatment effects. All treatments produced similar yields, indicating that successful organic production of these vegetables is possible in Kentucky. Input costs for organic were 37% higher than conventional, due to the cost of organic fertilizer. The organic system required nearly 50% more labor hours than conventional or low-input. The low-input system was the most cost effective, with 58% less input expenses than the conventional system. Microarray analysis of approximately 37,500 Glycine max transcripts did not show significant differences in the gene expression between plants grown organically and conventionally, in plots with significant soil chemical and microbial differences. An experiment in progress is investigating changes in plant gene expression using real time RT-PCR in tomatoes grown in autoclaved soil and native field soil.

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