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Effects of Water Distribution Uniformity on Waxy Corn (Zea mays L.) Yield: Preliminary Results  [PDF]
Lucia Bortolini, Marco Martello
Journal of Water Resource and Protection (JWARP) , 2014, DOI: 10.4236/jwarp.2014.611098
Abstract:

To face climatic changes, the increase of frequency and severity of droughts, and economic development pressures, Water Management Institutions point at the necessity of water conserving. A sustainable demand-led approach is the most viable option, focusing on achieving more efficient irrigation practices instead of less sustainable expansion of supply. The aim of this work is to investigate on some aspects of the rational water management for the irrigation of corn in order to evaluate the actual possibility of introduction of drip irrigation systems on the Venetian Plain. Trials were carried out on a farm located in Isola della Scala (Verona, Italy) in an area of about 13 ha (12 ha with a drip irrigation system and 1 ha with a solid-set sprinkler system); the effects of the performance of the two systems on waxy corn yield were considered. In particular, water distribution uniformity, water use efficiency, and yield performance of irrigation systems were evaluated. DUlq and CU coefficients for distribution uniformity and IWUe and WUEb indexes for water use efficiency were calculated. To visualize and better analyze the distribution uniformity, the crop yield and the efficiency parameters, ArcGIS 10 (ESRI?) with IDW interpolation were used to create maps. First results show a good water uniformity distribution in the drip irrigation system but only with a careful and proper design of the entire system. As regards the water use efficiency, drip irrigation values are lower than those of sprinkler irrigation (-46% for IWUe and -25% for WUEb), probably due to different irrigation management and water volumes used: in fact, drip irrigation was scheduled every three days, while only supplemental operations were done for sprinkler irrigation. No statistical correlation was found between application rate and yield for both

Identification of RAPD Markers for Northern Corn Leaf Blight Resistance in Waxy Corn (Zea mays var. ceratina)  [PDF]
Juthaporn Khampila,Piyada Theerakulpisut,Kamol Lertrat,Weerasak Saksirirat
Asian Journal of Plant Sciences , 2008,
Abstract: A F2 population from a cross of the waxy corn inbreds 209W and 241 W was used to determine random amplified polymorphic DNA (RAPD) markers linked to Northern Corn Leaf Blight (NCLB) resistance via Bulked Segregant Analysis (BSA). Resistant and susceptible DNA bulks were constructed using the segregating F2 plants based on phenotypic reaction against NCLB infection. In total, two hundred and twenty two decamer primers were used to identify three polymorphic bands observed between the bulks. The primers OPE02, OPJ18 and OPX04, generated the polymorphic DNA fragments of approximately 1200, 650 and 500 bp, respectively. These RAPD bands were present in only in NCLB-resistant bulk and 241W resistant parent. The study revealed that RAPD markers associated to NCLB resistance is potentially useful for the identification of genotyped individuals carrying NCLB resistant traits in breeding programs.
Some aspects of cultivation and utilization of waxy maize (Zea mays L. ssp. ceratina)
Agnieszka Klimek-Kopyra,Aleksander Szmigiel,Tadeusz Zaj?c,Agnieszka Kidacka
Acta Agrobotanica , 2012, DOI: 10.5586/aa.2012.001
Abstract: This paper is a review of available literature on Zea mays L.ssp.ceratina. It contains information on the origin, cul- tivation and utilization of waxy maize in the world and can be a contribution to the development of new research on maize cultivation and starch processing technology. Maize, as an old and economically important cereal, played an enormous role in the ancient civilisations of the New World. Among the maize subspecies compared, Z. mays ssp. indurata and Z. mays ssp. indentata are now the most important in Poland. The subspecies Z. mays ssp. saccharata has a marginal role, while Z. mays ssp. ceratina has not been hitherto cultivated. Decisions to introduce the subspecies Z. mays ssp. ceratina into cultivation are based on different grounds, taking into account both agro-climatic conditions and industrial uses of grain processing products. The growing demand for maize grain, stimulated by the increased demand for maize starch and oil in the global market as raw materials that are important in food production, is an impulse for the development of agrobiological research. The development of the starch industry, associated with the demand for industrial starch, will probably contribute to increased interest in this subspecies in Central Europe, also including Poland. Waxy maize grain can be a major ingredient of high-energy feeds for livestock, replacing in this role the type of maize that has been grown for this purpose until now. A great advantage of waxy maize is its specific structure of starch, due to its unique and high amylopectin content (95-98%), which creates unlimited possibilities of industrial use. Currently, waxy maize acreage in Europe does not exceed 2% of the maize crop area in this continent.
Carbohydrate Characters of Six Vegetable Waxy Corn varieties as Affected by Harvest Time and Storage Duration  [PDF]
S. Simla,K. Lertrat,B. Suriharn
Asian Journal of Plant Sciences , 2010,
Abstract: Six varieties of vegetable waxy corn (Zea mays var. ceratina) popular among growers and consumers in Thailand were analyzed for their carbohydrate compositions at different harvest times from 15 days after Pollination (DAP) to maturity and a corn variety was stored at different durations. All sugar compositions increased with Days after Pollination (DAP) to the peak and then declined, whereas total starch, amylopectin and phytoglycogen compositions increased with DAP and were highest in mature kernels. The accumulation timings of carbohydrate compositions were different among varieties and compositions. Suitable harvest times can vary between 17 and 25 DAP. The highest harvest durations were observed in Tien Baan Kao and Big White 852 being 9 and 7 days, respectively. Storage of waxy corn under ambient conditions resulted in rapid loss of sugar contents, whereas total starch, amylopectin and phytoglycogen were increased. Low storage temperature is required to maintain shelf-life of waxy corn products. These varieties are highly recommended for commercial production and can be used as germplasm sources for waxy corn improvement.
Influence of Corn (Zea mays L.) Cultivar Development on Grain Nutrient Concentration  [PDF]
Carla Fernanda Ferreira,Ant?nio Carlos Vargas Motta,Stephen A. Prior,Carlos Bruno Reissman,Nicolas Z. dos Santos,Juarez Gabardo
International Journal of Agronomy , 2012, DOI: 10.1155/2012/842582
Abstract: While corn productivity has been increased by the adoption of high-yield hybrids, there are concerns that increased grain potential may be associated with diminished grain nutrient concentration. Ten corn (Zea mays L.) cultivars representing five technological levels (landrace variety, commercial variety, and double, triple, and single cross-hybrids) were cropped on a Rhodic Ferralsol Eutric soil with high fertility in 2006 (dry year) and 2007 (normal year) in Rolandia County, Brazil. At maturity, grain was evaluated for concentrations of P, K, Ca, Mg, Fe, Mn, Zn, and Cu. In general, differences among cultivars were noted for all nutrients in both years. Concentrations of P, K, Fe, and Mn were lower in the dry year, while Ca, Mg, Cu, and Zn were higher. Soil water availability appeared to exert more influence on grain nutrient concentration than did cultivar development; nutrient removal due to grain harvest was also greatly influenced by rainfall patterns and their impact on corn productivity. Even though genetic differences were noted, which may be useful to breeding programs, long-term testing in subtropical environments will be required to clarify the interaction between genetics and climate events on grain nutrient quality and exportation. 1. Introduction Grain nutrient concentration plays a key role in seed quality as it relates to seed reserves required to germination and nutritional feed value [1]. Grain nutrient concentration can also provide information related to nutrient exportation (i.e., removal from the field) and the necessity for soil nutrient replenishment through fertilization [2, 3]. Despite these important issues, tissue analysis has traditionally focused on leaf, rather than grain, nutrient levels to diagnose whole-plant nutritional status. Recently, it has been suggested that genetic selection in wheat (Triticum aestivum L.) has contributed to reduced levels of some micronutrients in grain [1]. Concerns regarding diminished grain quality have spread to other crops such as corn (Zea mays L.). In a study evaluating six corn hybrids released between 1959 and 1988, lower values of micronutrients were found in the newer hybrids [4]. A study of four tropical corn cultivars released between 1970 and 1990 noted some differences among cultivars; however, it was not clear whether new cultivars designed for higher yields would result in decreased grain nutrient concentration [5]. Similar variation in grain nutrient concentrations among corn hybrids have also been reported in different field studies [3]. Other factors, such as soil type and
Granules morphology and rheological behavior of green banana (Musa cavendishii) and corn (Zea mays) starch gels
Izidoro, Dayane Rosalyn;Demczuk Junior, Bogdan;Haminiuk, Charles Windson Isidoro;Sierakowski, Maria Rita;Freitas, Renato Jo?o Sossela de;Scheer, Agnes de Paula;
Ciência e Agrotecnologia , 2007, DOI: 10.1590/S1413-70542007000500026
Abstract: in this work, it was used starch obtained from green banana (musa cavendishii) and commercial corn (zea mays) starch in order to compare the granule morphology and the rheological behavior of these gel-starches. images of starch granules morphology were obtained from scanning electron microscope (sem). the banana starch granules presented an oval and ellipsoidal shape with irregular diameters. neverthless, the granules of corn starch showed a poliedric shape, with different sizes. the rheological behavior of gel starch solutions showed a non-newtonian character with a pseudoplastic behavior. herschel-bulkley model gave a good description on the rheological behavior of the gel starch. banana gel-starch solutions showed higher values of shear stress and apparent viscosity when compared with corn gel-starch solutions. a progressive decrease in shear stress and viscosity occurred with the addition of sodium chloride and sucrose.
The Combined Effects of Fungicides and Arbuscular Mycorrhiza on Corn (Zea mays L.) Growth and Yield under Field Conditions  [PDF]
S. Samarbakhsh,F. Rejali,M.R. Ardakani,F. Pak Nejad
Journal of Biological Sciences , 2009,
Abstract: With respect to the significance of the combined effects of fungicides application and Arbuscular Mycorrhizal fungi on the growth and yield of different crop plants such as corn (Zea mays L.) a field experiment was conducted. The objectives were to determine: (1) the combined effects of different fungicides and different arbuscular mycorrhiza (AM) species on the growth and yield of corn and (2) the efficiency of different AM species in symbiosis with corn plants, treated by different fungicides, under field conditions. Four AM treatments including control (M0), Glomus mosseae (M1), G. etunicatum (M2) and G. intraradices (M3) and four fungicide treatments including control (F0), benomyl (F1), vitavax (F2) and captan (F3) were tested in a factorial fashion on the basis of a completely randomized block design in three replicates in 2006. Different species of AM significantly affected corn growth and yield when subjected to different fungicides treatments. G. mosseae and corn plants established the most efficient symbiosis. In addition, fungicide benomyl had the least unfavorable effects on the colonization of corn roots by AM species. Determination of the appropriate rates of fungicides for treating seeds to alleviate the unfavorable effects of fungicides on plant growth, especially when in symbiosis with AM species, is of great significance.
Evaluation of Competition in Corn (Zea mays L.) and Pumpkinseed (Cucurbita pepo var. styriaca) Intercropping by Reciprocal Yield Model and Some Competitive Indices  [PDF]
M. Khoramivafa,S. Zehtab Salmasi,A. Dabbagh Mohammadi Nassab,A.Javanshir
Journal of Agronomy , 2006,
Abstract: In order to evaluate the intra- and inter specific competition of corn (Zea mays L.) and pumpkinseed (Cucurbita pepo var. styriaca) by reciprocal yield model, two years field experiments were conducted at the research station of faculty of Agriculture, University of Razi, Kermanshah, Iran, in 2003-2004. The experiments laid out as factorial based on randomized complete block design. The interspecific competition of corn on pumpkinseed was greater than that of Pumpkinseed`s on corn. Corn Intraspecific competition in second year was greater than that first year; due to delay in planting date. According to relative competitive effects, intraspecific competition affected corn plants less than pumpkinseed plants.
Molecular responses of Bt transgenic corn (Zea mays L.) plans to salt (NaCl) stress  [PDF]
Mohamed Salah Beltagi
Australian Journal of Crop Science , 2008,
Abstract: Non-transformed and Bt transgenic crop lines of a hybrid (YieldGard 2) corn (Zea mays L.) plants in the 4th leaf stage were subjected to 0, 50, 100 and 150 mM NaCl. Significant (P = 0.05) reduction in growth of non-traformed plants was recorded under almost all levels (50, 100 and 150 mM) of salt (NaCl) stress; while, the growth of the Bt transgenic corn plants showed no significant changes under the same levels of salt stress. Chlorophyll a contents were reduced at 150 mM NaCl only; but did not change in the BT transgenic corn plants. Chlorophyll b was not responsive to NaCl treatments in both non-transformed and Bt transgenic corn plants. Chlorophyll stability index (CSI) were always higher in the Bt transgenic than in the non-transformed corn plants under all salinity levels. The analyses of SDS-PAGE revealed relative stability in the patterns of protein bands in the Bt transgenic corn plants under salinity stress. The sum of optical densities of protein bands was higher in the Bt transgenic corn plants. In response to salinity stress, a group of polypeptide (76.96, 59.38, 41.56, 33.5 and 31.26 KDa) were newly synthesized in both non-transformed and Bt transgenic plants. Salt-susceptible polypeptides of molecular weights 325.47, 32.64 and 24.17 KDa were found only in non-transformed corn plants and completely disappeared under all level of salt stress; while two polypeptides of molecular weights 38.59 and 30.61 KDa were totally inhibited in all salt-stressed corn plants. The synthesis of another four polypeptides (298.81, 99.82, 20.79 and 19.43 KDa) was solely specific to the Bt transgenic corn plants. Stability of chlorophyll pigments and molecular weights of salt stress responsive proteins are key genetic determinants of salt stress in Bt transgenic corn plants.
Agronomic Performance of Some Corn Cultivars (Zea mays L.) in Middle Anatolia
Cetin Palta,Ufuk Karadavut,Mehmet Tezel,Seref Aksoyak
Journal of Animal and Veterinary Advances , 2012, DOI: 10.3923/javaa.2011.1901.1905
Abstract: This study was conducted to determine some yield characters of corn cultivar in Konya province which is located in Middle Anatolian region in 2003 and 2004 years. Eight corn cultivars (Monton, Monzon, Ranchero, Ada, Montel, Progen, 35P12 and TTM 8119) were tested in randomized complete block design with four replicates. Corn yield changed from 10397 kg ha-1 (cv Ranchero) to 12725 kg ha-1 (cv Monton). Corn yield level in Konya was comperatible to other region in Turkey. Therefore, it can be new and large corn production area in coming years.
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