Nitrogen Fertilizer Research Papers - Academia.edu (original) (raw)

Establishment of seedlings of Bromus inermis, a native grass species of China, into a degraded steppe grassland was studied in an experiment with a factorial combination of different soil disturbance (control and harrowing), cutting... more

Establishment of seedlings of Bromus inermis, a native grass species of China, into a degraded steppe grassland was studied in an experiment with a factorial combination of different soil disturbance (control and harrowing), cutting post-sowing (control and cutting), nitrogen (N) fertilizer application (0 and 100 kg KNO3 hm−2) and seed rate (400, 800 and 1200 seeds m−2) treatments. Seedling emergence and survival rates, and plant performance, were followed over 2 years. Seedling emergence was increased by soil disturbance (harrowing). Cutting post-sowing and N fertilizer application did not increase seedling emergence. Seedling survival rates at the end of first growing season were strongly influenced by harrowing and the use of higher seed rates. Seedling height was higher in the harrowing and the N fertilizer application treatments and at the higher seed rates. Seedling survival rates in the second growing season were low but much higher with harrowing than the other treatments. Soil disturbance by harrowing may have increased contact between seed and soil, and reduced competition from established plants. It is concluded that, for the restoration of degraded semi-arid grassland in China by re-seeding, soil surface disturbance is necessary for successful seedling establishment, and modest seeding rates should be used to control costs.

Natural toxins, such as mycotoxins, have emerged as a significant factor affecting the safety image of cereal grains as a raw material for the food and feed industry. The aim of the present study was to investigate the contents of... more

Natural toxins, such as mycotoxins, have emerged as a significant factor affecting the safety image of cereal grains as a raw material for the food and feed industry. The aim of the present study was to investigate the contents of trichothecenes in representative samples of oats during official variety, nitrogen fertilization and organic farming trials in Finland, 1997–1999. Further objectives were to promote industry and commerce by selection of high-quality oat varieties for various applications. The official variety trials conducted at 8–10 locations were managed following standard protocol. There were 2 types of agronomy trial, the first included comparison of oat cultivars grown in conventional and organic farming systems at 6 locations, and the second used 5 nitrogen rates (0, 40, 80, 120 and 160 kg N ha-1) at 2 locations. Regardless of wet cold summer occurring in Finland during 1998, the concentrations of Fusarium toxins were lowest during this 3 year monitoring period. More...

SUMMARY - Gluten strength is the main determinant of the end-use quality in durum. Wheat gluten strength is affected by genetic variation at genes coding for gliadins and glutenins, and by environmental factors. We grew 110 recombinant... more

SUMMARY - Gluten strength is the main determinant of the end-use quality in durum. Wheat gluten strength is affected by genetic variation at genes coding for gliadins and glutenins, and by environmental factors. We grew 110 recombinant inbred lines of the cross Jennah Khetifa x Cham1 in 13 environments (sites and years), and analyzed gluten strength in the resulting grain

Two cherry tomato plant cultivars (Lycopersicon esculentum Miller, cultivars ‘Koko’ and ‘Pepe’) were supplied with high (395 ppm), medium (266 ppm) and low (199 ppm) concentrations of nitrogen to determine the influence of nitrogen... more

Two cherry tomato plant cultivars (Lycopersicon esculentum Miller, cultivars ‘Koko’ and ‘Pepe’) were supplied with high (395 ppm), medium (266 ppm) and low (199 ppm) concentrations of nitrogen to determine the influence of nitrogen fertilization on development, cultivar preference and honeydew production by greenhouse whiteflies, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae). The nitrogen, protein, and chlorophyll contents of tomato leaves were higher in the

ABSTRACT Maize grain yields have increased dramatically over the past fifty years, and concurrently end-uses have proliferated requiring special quality characteristics. Plant breeders have developed many specialty types of maize, all of... more

ABSTRACT Maize grain yields have increased dramatically over the past fifty years, and concurrently end-uses have proliferated requiring special quality characteristics. Plant breeders have developed many specialty types of maize, all of which are influenced by the agronomic practices used to produce the crop. Grain yield increases have resulted in lower protein concentration except when the yield increase resulted from nitrogen fertilizer application. Irrigation improves the biological value of protein, while higher nitrogen application rates alter the amino acid balance thereby reducing the nutritional value. Kernel breakage susceptibility and kernel density increase with higher nitrogen fertilizer application rates, and are reduced by irrigation. Extractable starch and oil concentration are largely influenced by hybrid choice, but small production practice effects have been documented. Essential mineral nutrient levels are often influenced by soil or foliar fertilizer application. The production of aflatoxin can be reduced by irrigation or other strategies to avoid water stress during grain fill. Although genetics usually exerts the largest effect on maize grain quality, agronomic practices are also important.

The effect of different levels of nitrogen N0(0kg/ha), N1(30 kg/ha), N2 (60 kg/ha), and N3 (90 kg/ha) and farmyard manure F0 (0 tonnes/ha), F1 (10 tonnes/ha), and F2 (20 tonnes/ha) on the yield and nutrient composition of spinach and its... more

The effect of different levels of nitrogen N0(0kg/ha), N1(30 kg/ha), N2 (60 kg/ha), and N3 (90 kg/ha) and farmyard manure F0 (0 tonnes/ha), F1 (10 tonnes/ha), and F2 (20 tonnes/ha) on the yield and nutrient composition of spinach and its uptake was investigated on a sandy loam soil. Yield; phosphorus, iron, manganese, zinc, and copper uptakes; and ascorbic acid content increased with the application of both the inorganic nitrogen fertilizer and the farmyard manure, with a maximum at the N3F2 level, i.e. at 90 kg N/ha with 20 tonnes FYM/ha. However, the contents of protein, β-carotene, and reducing sugars were maximum at the highest dose of nitrogen without the application of farmyard manure.

3 Abstract: The application of organic wastes combined with or without mineral fertilizer to soil is considered as a good management practices in any agricultural production system because it improves, plant quality and soil fertility.... more

3 Abstract: The application of organic wastes combined with or without mineral fertilizer to soil is considered as a good management practices in any agricultural production system because it improves, plant quality and soil fertility. The objective of the present study is to evaluate the effect of three compost types (plant residues, animal residues and mixed) when mixed with mineral

Tritrophic interactions (plant—herbivore—natural enemy) are basic components of nearly all ecosystems, and are often heavily shaped by bottom-up forces. Numerous factors influence plants’ growth, defense, reproduction, and survival. One... more

Tritrophic interactions (plant—herbivore—natural enemy) are basic components of nearly all ecosystems, and are often heavily shaped by bottom-up forces. Numerous factors influence plants’ growth, defense, reproduction, and survival. One critical factor in plant life histories and subsequent trophic levels is nitrogen (N). Because of its importance to plant productivity, N is one of the most frequently used anthropogenic fertilizers in agricultural production and can exert a variety of bottom-up effects and potentially significantly alter tritrophic interactions through various mechanisms. In this paper, the potential effects of N on tritrophic interactions are reviewed. First, in plant-herbivore interactions, N availability can alter quality of the plant (from the herbivore’s nutritional perspective) as food by various means. Second, nitrogen effects can extend directly to natural enemies through herbivores by changes in herbivore quality vis-à-vis the natural enemy, and may even provide herbivores with a defense against natural enemies. Nitrogen also may affect the plant’s indirect defenses, namely the efficacy of natural enemies that kill herbivores attacking the plant. The effects may be expressed via (1) quantitatively and/or qualitatively changing herbivore-induced plant volatiles or other plant features that are crucial for foraging and attack success of natural enemies, (2) modifying plant architecture that might affect natural enemy function, and (3) altering the quality of plant-associated food and shelter for natural enemies. These effects, and their interactive top–down and bottom-up influences, have received limited attention to date, but are of growing significance with the need for expanding global food production (with accompanying use of fertilizer amendments), the widening risks of fertilizer pollution, and the continued increase in atmospheric CO2.

The dry matter yield (DMY) of Napier grass was significantly affected by plant height at cutting, fertilizer application and their interaction. The highest yield, 12.34 t/ha, was from cutting at 1.0 m with 92 kg N kg/ha. Plant height at... more

The dry matter yield (DMY) of Napier grass was significantly affected by plant height at cutting, fertilizer application and their interaction. The highest yield, 12.34 t/ha, was from cutting at 1.0 m with 92 kg N kg/ha. Plant height at cutting had a significant positive effect on number of leaves per tiller and per plant. The internodes and internode length per tiller, the number of tillers per plant and basal circumference were positively affected by both plant height at cutting and fertilizer application, but the effect of leaf:stem ratio on DMY was negative. Copyright © 2003 Whurr Publishers Ltd

Seed variety is the most important input that contributes to the yield, growth and to the quality improvement of the annual forage plants. By keeping this fact in view an experiment was conducted in the Siddique Farm, Tando Adam, Sindh to... more

Seed variety is the most important input that contributes to the yield, growth and to the quality improvement of the annual forage plants. By keeping this fact in view an experiment was conducted in the Siddique Farm, Tando Adam, Sindh to determine the best suited cultivar for Rhodes grass in its climatic zone. The experiment was laid out in a randomized complete block design (RCBD) with three replications. The economic and qualitative parameters studied during the research study was plant height, tillers / plant, leaves / tillers, leaf area, green fodder yield, dry matter yields, crude protein, ether extract, crude fibre, nitrogen free extract, and ash contents respectively. Analysis of Variance showed that commercial cultivars were significantly varied from each other for dry fodder yield and other recorded characters. The cultivar Finecut produced highest (6.75 ton/ha/cut) dry fodder yield per hectare per cut. The maximum plant height (131.98 cm), tillers / plant (5.12), leaves / tillers (10.66), leaf area (323.21 cm 2), green fodder yield (23.53 ton/ha/cut), and crude protein content (9.23) was also observed for the cultivar Finecut. However, the other Rhodes grass varieties showed less yielding results for all the agronomic parameters. Statistical analyses of all the research parameters are elaborated in Table 01 and Table 02 respectively. From the obtained statistical results it can be concluded that the cultivar Finecut has a best genetic potential to perform better and hence it is recommended that these cultivars are best suited to cultivate in the arid region of Tando Adam, Sindh – Pakistan.

In order to evaluate the effect of the cutting frequency and types of nitrogen fertilization on three elephant grass genotypes, a field trial was carried in the Universidad de Los Andes farm, in El Vigia, Merida state, Venezuela, located... more

In order to evaluate the effect of the cutting frequency and types of nitrogen fertilization on three elephant grass genotypes, a field trial was carried in the Universidad de Los Andes farm, in El Vigia, Merida state, Venezuela, located at 67 masl. A random bocks design with three replications was used; treatments were two cutting frequencies (F1: 49 and F2: