Ironite and phosphorus were applied to plots seeded to hard red wheat and barley to find their effect on crop yield and nutrient uptake at various stages of crop development. Phosphorous caused significant increases in yield in both wheat and barley, where Ironite caused few changes in yield. Ironite caused significant increases in percent of nutrients stored in barley grain, but generally had little effect on nutrient uptake by plants at boot or milk stage. Phosphorous tended to decrease the percent nutrient uptake by plants.

The standard procedure for determining nitrogen (N) status in small grains is to sample lower stem tissue for nitrate (NO₃) analysis. The tissues are then submitted to a laboratory for analysis. Sap nitrate (NO₃) can be analyzed in the field, immediately after collecting the sample, using a Cardy meter. Guidelines for sap analysis have not yet been determined. The objectives of this study were to: (i) correlate NO₃-N in dried stem tissue with sap NO₃-N , and (ii) develop sap NO₃ test guidelines for N management in durum and feed barley. In November 1998 one variety of durum (Kronos) and one variety of feed barley (Gustoe) were planted at the Maricopa Agricultural Center. Three N rates (80, 200, and 400 lbs N/acre) were applied in four split applications. Each treatment was replicated five times in a randomized complete block design. Samples were collected from lower stems at the 3-4 leaf 2 node, flag leaf visible, and heading growth stages. Grain yields ranged from 4330 lbs/A to 6794 lbs/A for Kronos and 3220 lbs/A to 4533 lbs/A for Gustoe. Correlation coefficients between stem NO₃-N and sap NO₃-N were 0.76 for Kronos and 0.60 for Gustoe. Sap NO₃-N analysis can be used to determine N status during the season for Kronos. Results for the barley suggest at low concentrations of NO₃ in the lower stem, the Cardy meter may underestimate NO₃ concentrations. This may be due to changes in moisture content in the stem as the season progresses.

Proper nutrient management is necessary for successful production of durum wheat in the desert. If grain protein content is less than 13 %, significant economic losses to growers can result. Late season nitrogen (N) fertilization can resolve this problem, but tissue test guidelines have not yet been established. The objectives of this study were to: (i) correlate NO₃-N in dried stem tissue with sap NO₃-N, (ii) determine the minimum NO₃-N concentration in lower stem tissue at heading associated with the critical grain protein content, and (iii) determine whether flag leaf head, or whole plant total N at heading can be used as indicators of N status. In November 1997 two varieties of durum wheat, Mohawk and Kronos, were planted at the Maricopa Agricultural Center. Five N rates (0, 100, 200, 300, and 400 lbs/A) were applied in four split applications. Each treatment was replicated three times in a randomized complete block design. Samples were collected from the lower stem, flag leaf head, and whole plant from each plot at heading and analyzed for total N. Grain yields ranged from 1663 to 6916 lbs/A for Mohawk and 1529 to 7060 lbs/A for Kronos. Maximum yields were achieved at 200 lbs N/A for both varieties. Grain protein content averaged 8.6% to 13.4% (Mohawk) and 9.1% to 13.8% (Kronos). Correlation coefficients between stem NO₃-N and sap NO₃-N were 0.96 for Mohawk and 0.97 for Kronos. Lower stem sap critical NO₃-N concentration in Kronos is 1100 ppm NO3 N and 1700 ppm NO₃-N for Mohawk at heading for a grain protein content of 13 %. Lower dried stem tissue critical NO₃-N concentration in Kronos is 5500 ppm NO₃-N and 7500 ppm NO₃-N for Mohawk for a grain protein content of 13 %. Nitrogen concentration in flag leaves, heads, and whole plants were highly correlated with N rate. Therefore, N concentration in these tissues could potentially be used as indicators of late-season N status.

The standard procedure for determining nitrogen (N) status in small grains is to sample lower stem tissue for nitrate (NO₃) analysis. The tissues are then submitted to a laboratory for analysis. Sap nitrate (NO₃) can be analyzed in the field, immediately after collecting the sample, using a Cardy meter. Guidelines for sap analysis have not yet been determined. The objectives of this study were to: (i) correlate NO₃-N in dried stem tissue with sap NO₃-N, and (ii) develop sap NO₃ test guidelines for N management in durum and feed barley. In November 1997 one variety of durum (Kronos) and one variety of feed barley (Gustoe) were planted at the Maricopa Agricultural Center. Three N rates (80, 200, and 400 lbs N/acre) were applied in four split applications. Each treatment was replicated five times in a randomized complete block design. Samples were collected from lower stems at the 3-4 leaf 2 node, flag leaf visible, and heading growth stages. Grain yields ranged from 5185 lbs/A to 7156 lbs/A for Kronos and 6314 lbs/A to 7517 lbs/A for Gustoe. Maximum yields were achieved at 200 lbs N/A for both varieties. Correlation coefficients between stem NO₃-N and sap NO₃-N were 0.79 for Kronos and 0.84 for Gustoe. Sap NO₃-N analysis can be used to determine N status during the season for both Kronos and Gustoe.

The economic effect of applying phosphorus at planting of durum wheat is directly correlated to the phosphorus that is available to the plants from the soil. For bicarbonate soluble phosphorus levels less than 6 ppm, there will likely be a positive economic effect from applying some phosphorus. At this site the soil phosphorus level was 4.8 ppm and the application of 200 pounds of 16-20-0 caused an increase in yield of 2101 pounds per acre. A cost of $23 per acre with a return of $168 per acre.

Grain quality is important to growers and buyers of durum. Growers are usually docked if their HVAC drops below 90% or their grain protein is below 13 %. The purpose of this study was to demonstrate the ability of nitrogen fertilizer application near flowering to increase HVAC and grain protein. Six commercial sites were chosen for this study and Kronos was the variety. The application of about 50 pounds of nitrogen per acre increased HVAC by from 81 to 93% and increased grain protein from 11.2 to 12.3% on average, similar to results obtained in the past.

Malting barley is not a widely planted crop in the Southwest, due to grain protein contents that can sometimes exceed the industry standard of 11.4 %. To achieve < 11.4% grain protein, careful nitrogen (N) management is needed. Tissue testing guidelines for N management for reduced grain protein and acceptable yields have not yet been determined for malting barley in the Southwest. The objectives of this study were to: (i) correlate NO₃-N in dried stem tissue with sap NO₃-N, and (ii) develop stem NO₃-N guidelines for N management in malting barley. In November 1997 two varieties of malting barley, Morex and Crystal, were planted at the Maricopa Agricultural Center. Five N rates (0, 60, 120, 180, and 240 lbs/acre) were applied in four split applications. Each treatment was replicated three times in a randomized complete block design. Samples were collected from lower stems at the 3-4 leaf 2 node, and flag leaf visible growth stages. Grain yields ranged from 1765 lbs/A to 3439 lbs/A for Morex and 2104 lbs/A to 4274 lbs/A for Crystal. Grain protein ranged from 7.6- 10.5% (Morex) and 7.0- 10.7% (Crystal). Correlation coefficients between stem NO₃-N and sap NO₃-N were 0.80 for Morex and 0.84 for Crystal. For Morex and Crystal, grain protein was within the malting industry grain protein range of 10.5- 11.4% at 240 lbs N/A, and yield was optimized at 180 lbs N/A. Sap NO₃ analysis can be a useful tool for determining N status of malting barley. Stem NO₃-N concentrations at 180 lbs N/A were generally within the optimum range for NO₃-N in small grains.

Ironite and phosphorus were applied to plots seeded to oats to find their effect on crop yield. The effects of both additives were positive, even though not statistically at the 90% level of confidence. The concern for lead and arsenic uptake by plants was also addressed as soil and plant samples were tested for these two elements. The results showed that no more arsenic nor lead were present in oat plants on Ironite plots than from check plots, as they approached maturity.

Many agricultural workers feel that 10-34-0 is a superior fertilizer for alfalfa since it is thought to move deeper in the soil with irrigation, be more available to the plant, and result in higher yields at equivalent rates compared to 11-52- 0. We found in our study with 24 cuttings over 3 years that alfalfa yields were similar if fertilized with 10-34-0 or 11-52-0 at equivalent rates. Total plant P was not affected by P fertilizer form or method of application. Broadcast 11- 52-0 resulted in higher soil P levels than water-run 10-34-0 and moved deeper in the soil profile. Broadcast 11-52-0 and water-run 10-34-0 appear to be equally effective P fertilizers for alfalfa in the irrigated southwest.

Submitted by Erika Demachki (erikademachki@gmail.com) on 2014-10-23T20:24:19Z No. of bitstreams: 2 Tese - Helenice Moura Gonçalves - 2012.pdf: 14046594 bytes, checksum: 955403e34d2ccd8db560e724fa1fdc53 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-10-23T20:28:40Z (GMT) No. of bitstreams: 2 Tese - Helenice Moura Gonçalves - 2012.pdf: 14046594 bytes, checksum: 955403e34d2ccd8db560e724fa1fdc53 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-10-23T20:28:40Z (GMT). No. of bitstreams: 2 Tese - Helenice Moura Gonçalves - 2012.pdf: 14046594 bytes, checksum: 955403e34d2ccd8db560e724fa1fdc53 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2012-03-23 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Organic agriculture is gaining ground and has been the subject of extensive discussions in different places on the planet. Given the interest and the prospect of growth in this market, Brazil is developing an infrastructure, which will allow to compete in this industry so dynamic leadership of the global market. Brazil is currently the largest producer of organic sugar. The state of Goiás has two large companies of expression in the production of organic sugar, including Jalles Machado S.A., where this research was developed. Knowing the uniqueness of a different fertilizer management for plantations under organic cultivation, there is a need to seek better understanding of the nutritional dynamics of the culture of sugarcane when it makes use of a fertilizer based on agroecological principles. Facing this new situation of advancement of this sector synergistically associated with organic agriculture, this research aimed to establish the Diagnosis and Recommendation Integrated System (DRIS) to the culture of organic sugarcane to establish criteria for the regional culture, making the programs more efficient fertilization. Samples were collected from soil and leaves in organic plantations, in two consecutive crop years 2009/2010 and 2010/2011. Both years collections totaled 192 samples being 112 points in the areas of plant-cane and 80 points in areas of ratoon-cane. The present observations was tabbed a database. The database was analyzed from two aspects, the traditional methods of Critical Levels and Ranges Sufficiency, and also by the methodology of the DRIS. It can be concluded that the cultivation of organic sugarcane, despite having featured in the Cerrado region, research is lacking to establish regional criteria fertilization. Differences were observed between the responses of fertilization cycles plant-cane and ratoon-cane for Goianésia, Goiás and research in the area of fertility and fertilization of the Cerrado soils can bring greater gains to the culture of organic sugarcane, either by increased production, by optimizing the use of organic inputs and the preservation of natural resources. / A agricultura orgânica vem conquistando espaço e tem sido tema de amplos debates em diversos lugares do planeta. Diante do interesse e da perspectiva de crescimento deste mercado o Brasil está desenvolvendo uma infra-estrutura, a qual permitirá que se dispute liderança neste setor tão dinâmico do mercado mundial. O Brasil é atualmente o maior produtor mundial de açúcar orgânico. O estado de Goiás possui duas grandes usinas de expressão na produção do açúcar orgânico, entre elas a Usina Jalles Machado S.A., onde a presente pesquisa foi desenvolvida. Conhecendo-se a singularidade de um manejo de adubação diferenciado para os canaviais sob cultivo orgânico, surge a necessidade de se buscar melhor entendimento da dinâmica nutricional da cultura da canade- açúcar quando se lança mão de uma adubação baseada nos preceitos agroecológicos. Frente a esta nova situação de avanço do setor sucroalcooleiro sinergicamente associado à agricultura orgânica, a presente pesquisa objetivou o estabelecimento do Sistema Integrado de Diagnose e Recomendação (DRIS) para a cultura da cana-de-açúcar orgânica para estabelecer critérios regionais para a cultura, tornando os programas de adubação mais eficientes. Foram coletadas amostras de solo e foliares em canaviais orgânicos, em duas safras consecutivas 2009/2010 e 2010/2011. Os dois anos de coletas totalizaram 192 pontos amostrados, sendo 112 pontos nas áreas de cana-planta e 80 pontos em áreas de cana-soca. Com as observações obtidas foi tabulado um banco de dados. O banco de dados foi analisado sob duas vertentes o método tradicional conhecido como métodos dos Níveis Críticos ou Faixas de Suficiência, e também, pela metodologia do DRIS. Pode-se concluir que a cultura da cana-de-açúcar orgânica, apesar de possuir destaque na região dos Cerrados, é carente em pesquisas que estabeleçam critérios regionais de adubação. Foram observadas diferenças entre as respostas de adubações dos ciclos cana-planta e cana-soca determinadas para a região de Goianésia, Goiás e que as pesquisas na área da fertilidade e adubação dos solos do Cerrado podem trazer ganhos maiores à cultura da cana-de-açúcar orgânica, seja por aumentos na produção, pela otimização no uso dos insumos orgânicos e pela preservação dos recursos naturais.