Macronutrient (N, P, K) and Redoximorphic Metal (Fe, Mn) Allocation in Leersia oryzoides (Rice Cutgrass) Grown Under Different Flood Regimes

Vegetated drainages are an effective method for removal of pollutants associated with agricultural runoff. Leersia oryzoides, a plant common to agricultural ditches, may be particularly effective in remediation; however, research characterizing responses of L. oryzoides to flooding are limited. Soil reduction resulting from flooding can change availability of nutrients to plants via changes in chemical species (e.g., increasing solubility of Fe). Additionally, plant metabolic stresses resulting from reduced soils can decrease nutrient uptake and translocation. The objective of this study was to characterize belowground and aboveground nutrient allocation of L. oryzoides subjected to various soil moisture regimes. Treatments included: a well-watered and well-drained control; a continuously saturated treatment; a 48-h pulse-flood treatment; and a partially flooded treatment in which water level was maintained at 15 cm below the soil surface and flooded to the soil surface for 48 h once a week. Soil redox potential (Eh, mV) was measured periodically over the course of the 8-week experiment. At experiment termination, concentrations of Kjeldahl nitrogen, phosphorus (P), potassium (K), iron (Fe), and manganese (Mn) were measured in plant tissues. All flooded treatments demonstrated moderately reduced soil conditions (Eh < 350 mV). Plant Kjeldahl nitrogen concentrations demonstrated no treatment effect, whereas P and K concentrations decreased in aboveground portions of the plant. Belowground concentrations of P, Mn, and Fe were significantly higher in flooded plants, likely due to the increased solubility of these nutrients resulting from the reductive decomposition of metal–phosphate complexes in the soil and subsequent precipitation in the rhizosphere. These results indicate that wetland plants may indirectly affect P, Mn, and Fe concentrations in surface waters by altering local trends in soil oxidation–reduction chemistry.     

Arbuscular mycorrhizal fungi influence tomato competition with bahiagrass

A strip-tillage production system for tomatoes (Lycopersicon esculentum Mill.) is impacted by nutrient competition from bahiagrass (Paspalum notatum Flügge). Tomato and bahiagrass differ in mycorrhizal responsiveness and our objective was to evaluate the influence of arbuscular mycorrhizal (AM) fungi on the competitive pressure of bahiagrass on growth of tomato. The first experiment evaluated the effect of bahiagrass competition, soil pasteurization, and AM fungal inoculation on tomato growth, P content, and root colonization in a low-P soil. Tomato grown alone was very responsive to mycorrhizal colonization - shoot dry mass of inoculated plants was up to 243% greater than that of noninoculated plants. Tomato grown with bahiagrass had reduced root and shoot growth across all treatments compared with tomato grown alone, but there was an increase in shoot mass following AM fungal inoculation across both pasteurized and nonpasteurized treatments resulting in a >50% increase in shoot dry mass of tomato compared to noninoculated controls. A second experiment was conducted to test bahiagrass competition, soil pasteurization, AM fungal inoculation, and P amendment on tomato growth in a moderate-P soil. With bahiagrass competition and no P addition, inoculation increased root mass by 115% and shoot mass by 133% in pasteurized soil; however, with the application of 32 mg P kg^-1 the trend was reversed and inoculated plants were smaller than noninoculated controls. We conclude that the role of mycorrhizae in plant competition for nutrients is markedly impacted by soil nutrient status and reduced P application may allow tomatoes to take advantage of their inherent responsiveness to mycorrhizae in a low to moderate soil-P environment.     

Impact of a soil feeding termite,<Emphasis Type="Italic"> Cubitermes niokoloensis</Emphasis>, on the symbiotic microflora associated with a fallow leguminous plant<Emphasis Type="Italic"> Crotalaria ochroleuca</Emphasis>

The influence of a soil-feeding termite nest (Cubitermes nikoloensis) on the development of a symbiotic microflora (rhizobia, arbuscular mycorrhizas) was tested in a pot experiment with a tropical legume (Crotalaria ochroleuca). Our results confirmed the role of soil-feeding termite nests as sites of high nutrient concentration, as a significantly higher content of available P and mineral-N was found in the mound wall. Arbuscular mycorrhizal spores increased in the soil near the termite mound. The mound soil itself almost totally depressed mycorrhizal establishment. The positive effect of the soils close to the mound was also evidenced by the number of nodules per root system as well as the nodule biomass per legume plant grown on this medium. Better growth of Crotalaria seedlings was observed in the soils from the mound wall; the shoot biomass increased by a factor of 9 and the root biomass by a factor of 6 as compared to the control soil (10 m away from the mound). Plant growth on soils from the immediate vicinity of the mound showed intermediate results but a higher N content per biomass unit. This probably reflected the association with arbuscular mycorrhiza and rhizobia. This work evidenced the linkage of plant nutrition to nutrient availability in mound material and the indirect mediating effect of the symbiotic microflora.     

Method for rapid assessment of nutrient supply capacity of soils

Abstract

A method to determine the nutrient supplying capacity of soils is presented which utilizes a nutrient solution in a lower container to supply designated nutrients to an upper container holding the soil. A series of nutrient solutions have been developed which maintain counter ion concentrations when a single nutrient is omitted from the solution. The validity of the technique is demonstrated by the agreement between plant yields, plant analysis data, and soil tests.     

Nutrient Leaching When Compost Is Part of Plant Growth Media

Engineered plant growth media must support plant growth while minimizing environmental impact. The objective of this research was to determine how different growth media influence nutrient leaching. Plant growth media contained varied amounts of soil, sand, compost that did or did not contain manure, and possible sorbents for phosphorus. If the plant growth media included compost derived partly from manure, leaching losses of nutrients were excessive due to the high nutrient load in the compost. Layering compost over the plant media mix resulted in lower nitrate concentrations in effluent (87 mg L^?1) compared with mixing compost into the media (343 mg L^?1); however, growth of prairie grasses was reduced because of dense media below the compost blanket (0.09 versus 0.31 g). Using lower amounts of compost that did not contain manure resulted in lower mean nitrate concentrations in effluent (101 versus 468 mg L^?1). Media that had no soil (13.3 mg L^?1) had greater loss of phosphorus after harvest for unsaturated drainage than media with soil (1.8 mg L^?1). To reduce nitrate leaching, only small amounts of low-nutrient compost (higher C:N ratio) should be incorporated into the media. If compost is applied as a surface blanket without incorporation, then soil should be added to the sand to reduce density of the media and increase plant growth.     

Relationship between in vitro production of auxins by rhizobacteria and their growth-promoting activities in Brassica juncea L.

Rhizobacteria were isolated from the rhizosphere of different Brassica species and assayed for their ability to produce auxins in vitro. The isolates varied greatly in their potential for auxin production (ranging from 0.33 to 11.40 µg ml^-1). L-Tryptophan (an auxin precursor) addition to the media increased the auxin production by several fold. Based upon in vitro auxin production and growth promotion of B. juncea seedlings caused by various isolates under gnotobiotic conditions, promising isolates were selected and tested in pot trial to observe their effects on growth, yield and oil content of the same Brassica species. Results showed that seed inoculation with different isolates of rhizobacteria significantly increased plant height (up to 56.5%), stem diameter (up to 11.0%), number of branches (up to 35.7%), number of pods per plant (up to 26.7%), 1,000-grain weight (up to 33.9%), grain yield (up to 45.4%) and oil content (up to 5.6%) over the uninoculated control. Isolate S54 gave the most promising and consistent results. Highly significant correlations between L-TRP-derived auxin production by plant growth-promoting rhizobacteria (PGPR) in vitro and grain yield (r =0.77^**), number of pods (r =0.78^**) and number of branches per plant (r =0.77^**) of B. juncea were found. It was hypothesized that these PGPR may influence the growth and yield of inoculated plants by production of auxins in the rhizosphere of inoculated plants from the L-TRP present in the root exudates, although other mechanisms of action might have also contributed.     

Effect of 2,4-diacetylphloroglucinol-producing and non-producing strains of Pseudomonas fluorescens on root development of pea seedlings in three different soil types and its effect on nodulation by Rhizobium

The effects of seed inoculation with the 2,4-diacetylphloroglucinol (DAPG)-producing Pseudomonas fluorescens strain F113 and a non-DAPG-producing Tn5 mutant of this strain (F113G22) on the growth of pea roots (Pisum sativum) was studied in three different soil types (sand, silty loam and clay) at two different temperatures (14°C and 21°C). It could be shown that high concentrations of DAPG in the rhizosphere of pea seedlings increased root mass production by >50% in all soil types providing that soil conditions did not limit plant growth. The presence of DAPG was associated with increased root length and root weight and transiently enhanced lateral root formation of pea plants. It is therefore suggested that DAPG can act as a plant hormone-like substance, inducing physiological and morphological changes in the plant that can lead to enhanced infection and nodulation by Rhizobium.     

Evaluation of agro-industrial by-products as nutrient source for plant growth

Nutrient leaching from dry (COD) and wet (COW) coffee, sisal (SIS), brewery barley malt (BEB) and sugar cane (FIC) by-products, and linseed (LIC) and niger seed cakes (NIC), and uptake by maize were studied in a pot experiment with tropical Alfisol. After three months, soils were leached to recover labile plant nutrients, and root and shoot biomass was harvested. The leachate from FIC-amended soil had the highest concentration of inorganic P (0.90 μmol L^?1), whereas the highest concentrations of potassium (K) (48,088 μmol L^?1) and calcium (2566 μmol L^?1) were determined in leachates from COD and BEB treatments, respectively. The amendments significantly increased K uptake by maize proportional to the amount of K applied, but the effects for other plant nutrients were small. The results indicated that pre-decomposition of agro-industrial by-products may increase the nutrient release in tropical soils.     

Do interactions with soil organisms mediate grass responses to defoliation?

Defoliation-induced changes in grass growth and C allocation are known to affect soil organisms, but how much these effects in turn mediate grass responses to defoliation is not fully understood. Here, we present results from a microcosm study that assessed the role of arbuscular mycorrhizal (AM) fungi and soil decomposers in the response of a common forage grass, Phleum pratense L., to defoliation at two nutrient availabilities (added inorganic nutrients or no added nutrients). We measured the growth and C and N allocations of P. pratense plants as well as the abundance of soil organisms in the plant rhizosphere 5 and 19 d after defoliation. To examine whether defoliation affected the availability of organic N to plants, we added ¹⁵N-labelled root litter to the soil and tracked the movement of mineralized ¹⁵N from the litter to the plant shoots.When inorganic nutrients were not added, defoliation reduced P. pratense growth and root C allocation, but increased the shoot N concentration, shoot N yield (amount of N in clipped plus harvested shoot mass) and relative shoot N allocation. Defoliation also reduced N uptake from the litter but did not affect total plant N uptake. Among soil organisms, defoliation reduced the root colonization rates of AM fungi but did not affect soil microbial respiration or the abundance of microbe-grazing nematodes. These results indicate that interactions with soil organisms were not responsible for the increased shoot N concentration and shoot N yield of defoliated P. pratense plants. Instead, these effects apparently reflect a higher efficiency in N uptake per unit plant mass and increased relative allocation of N to shoots in defoliated plants. The role of soil organisms did not change when additional nutrients were available at the moment of defoliation, but the effects of defoliation on shoot N concentration and yield became negative, apparently due to the reduced ability of defoliated plants to compete for the pulse of inorganic nutrients added at the moment of defoliation.Our results show that the typical grass responses to defoliation—increased shoot N concentration and shoot N yield—are not necessarily mediated by soil organisms. We also found that these responses followed defoliation even when the ability of plants to utilize N from organic sources, such as plant litter, was diminished, because defoliated plants showed higher N-uptake efficiency per unit plant mass and allocated relatively more N to shoots than non-defoliated plants.     

Response of neem (Azadirachta indica A. Juss) to indigenous arbuscular mycorrhizal fungi, phosphate-solubilizing and asymbiotic nitrogen-fixing bacteria under tropical nursery conditions

Neem (Azadirachta indica A. Juss) seedlings were inoculated with arbuscular mycorrhizal (AM) fungi, Glomus intraradices Schenck and Smith and G. geosporum (Nicol. and Gerd.) Walker, Azospirillum brasilense, and phosphate-solubilizing bacteria (PSB) individually or in various combinations in unsterile soil under nursery conditions. Seedlings were harvested at 60 and 120 days after transplantation. Microbial inoculation resulted in increased mycorrhizal colonization, greater plant height, leaf area and number, root collar diameter, biomass, phosphorus, nitrogen and potassium content, and seedling quality. Inoculated seedlings also had low root/shoot ratios and low nutrient utilization efficiencies. Populations of PSB declined with seedling growth; contrarily populations of A. brasilense increased. A. brasilense and PSB populations were related to each other and influenced root colonization by AM fungi. Microbial inoculation effects were greatest when seedlings were inoculated with a combination of microbes rather than individually. This clearly indicates that these microorganisms act synergistically when inoculated simultaneously, with maximum response being when both AM fungi were coinoculated with A. brasilense and PSB. The results emphasize the importance of microbial inoculations for the production of robust, rapidly growing seedlings in nurseries and illustrate the advantage of inoculating soils of a low microbial population with indigenous microbes.     

The effects of organic amendments on the interactions between a nematophagous fungus Arthrobotrys oligospora and the root-knot nematode Meloidogyne mayaguensis parasitizing tomato plants

The aim of this study was to examine the effects of amendments with leaf biomass on the development of tomato plants in a soil where root-knot nematodes (Meloidogyne mayaguensis) and/or a nematophagous fungus (Arthrobotrys oligospora, strain ORS 18697) had been inoculated. Six origins of leaf biomass were chosen: Acacia mangium, Acacia holosericea, Eucalyptus camaldulensis, Casuarina equisetifolia, Azadirachta indica and Sorghum vulgare. These leaf biomass types inhibited the development of the aerial parts of the tomato plants. This negative effect was not observed when the fungus was inoculated. On the contrary, plant growth was stimulated. Moreover, the antagonistic activity of Arthrobotrys oligospora was strengthened in the presence of ground leaf powder, especially that from Acacia holosericea. The effects of phenolic compounds on fungal growth and predatory activity and on plant growth are discussed.     

Glacially abraded rock flour from Greenland: Potential for macronutrient supply to plants

Rock flour (RF) is a fine‐grained material produced naturally by glacial movement and resulting bedrock abrasion. In Greenland fluvial transported RF from the inland ice sheet sediments in riverbeds and marine outflows. This fine‐sized RF (50% < 9.8 µm) has a high reactivity and may therefore potentially be used to rejuvenate nutrient poor soils and provide nutrients to plants. The aim of this study was to evaluate the ability of a RF from Greenland to supply P, K, Mg, and S to plants. A double‐pot system was used, in which ryegrass (Lolium perenne L.) could take up nutrients from both a hydroponic solution and a soil‐compartment with or without RF amendment; a soil mixture or pure sand was used in the soil‐compartment to estimate RF‐soil interaction effects. Omission of single nutrients from the hydroponic solution allowed assessment of which nutrients the RF in the soil‐compartment was able to supply. Ryegrass biomass was harvested four times during 62 days. We found that RF could supply K continuously to plants grown in soil or sand, but insufficient to fully circumvent K deficiency. During 62 days 5.8% and 4.3% of the applied K from RF was accumulated in the aboveground plant tissue in soil and sand, respectively. Mg was supplied from RF to plants in sand, but no significant effects were observed in soil, possibly due to background soil Mg availability. The amounts of P and S supplied to plants were insignificant. These results indicate the potential of Greenland RF to act as a slow release K and Mg fertilizer.     

Plant growth enhancement and suppression of Macrophomina phaseolina causing charcoal rot of peanut by fluorescent Pseudomonas

A plant growth-promoting bacterial strain, GRC₂, was isolated from potato rhizosphere and characterized as fluorescent Pseudomonas. It produced a hydroxamate-type siderophore in iron-deficient tryptic soy medium. The production of hydrocyanic acid and indole acetic acid was also recorded under normal growth conditions. The strain showed a strong antagonistic effect against Macrophomina phaseolina, a charcoal rot pathogen of peanut, when co-cultured on tryptic soy agar medium. The growth inhibition of M. phaseolina was 74% after 5 days of incubation. Bacterization of peanut seeds with fluorescent Pseudomonas GRC₂ resulted in increased seed germination, early seedling growth, fresh nodule weight, grain yield and reduced charcoal rot disease of peanut in M. phaseolina-infested soil as compared with control. A streptomycin-resistant marker of the bacterium GRC₂^strep+ was used to monitor root colonization, which positively confirmed the efficient colonization of peanut root. Seed bacterization reduced charcoal rot disease in M. phaseolina-infested soil as compared with the control by 99%, making the organism a potential biocontrol agent against charcoal rot of peanut.     

紫茎泽兰和黄顶菊入侵对土壤微生物群落结构和旱稻生长的影响

为比较入侵植物与本地植物对土壤微生态影响的差异, 探索外来植物入侵的土壤微生物学机制, 本研究通过同质园试验, 比较分析了2种入侵菊科植物(紫茎泽兰、黄顶菊)和2种本地植物(马唐、猪毛菜)对土壤肥力和微生物群落的影响, 并通过盆栽反馈试验验证入侵植物改变后的土壤微生物对本地植物旱稻生长的反馈作用。同质园试验结果表明: 2种入侵植物和2种本地植物分别对土壤微生态产生了不同的影响, 尤其是紫茎泽兰显著提高了土壤有效氮、有效磷和有效钾含量,紫茎泽兰根际土壤中有效氮含量为39.80 mg·kg^-1,有效磷含量为48.52 mg·kg^-1。磷脂脂肪酸指纹图谱结果表明, 2种入侵植物与2种本地植物相比, 较显著增加了土壤中放线菌数量, 而紫茎泽兰比其他3种植物显著增加了细菌和真菌数量。盆栽结果表明: 黄顶菊生长过的土壤灭菌后比灭菌前旱稻株高增加113%, 紫茎泽兰也使旱稻的株高增加17%。由以上结果可知, 紫茎泽兰和黄顶菊可能通过改变入侵地土壤的微环境, 形成利于其自身生长扩散的微生态环境从而实现其成功入侵。     

Response of yield and nutrients uptake of pea plants to silicate under sandy soil conditions

Desertic soils in Egypt are mostly sandy soils and have issues, due to their sandy nature, related to physical properties and the low potential for productivity. The aim of this study was to investigate the effect of silicon as potassium silicate on yield and nutrient uptake of pea (Pisum sativum L.) plant in sandy soil during the growth seasons of 2014–2015. Spraying of different rates of silicon significantly increased yield, biomass, 100 seed weight and nutrients accumulation as compared to unsprayed plants. The greatest values of photosynthetic pigments, plant height, and nutrients accumulation of plants were observed with 500 mg L^?1 silicon. Also, the highest percentage increase in fresh pod yields and protein of 82.5% and 45%, respectively, was recorded from 500 mg L^?1 silicon.     

Nutrient availability and corn growth in a poultry litter biochar‐amended loam soil in a greenhouse experiment

Nutrient‐rich biochar produced from animal wastes, such as poultry litter, may increase plant growth and nutrient uptake although the role of direct and indirect mechanisms, such as stimulation of the activity of mycorrhizal fungi and plant infection, remains unclear. The effects of poultry litter biochar in combination with fertilizer on mycorrhizal infection, soil nutrient availability and corn (Zea mays L.) growth were investigated by growing corn in a loam soil in a greenhouse with biochar (0, 5 and 10 Mg/ha) and nitrogen (N) and phosphorus (P) fertilizer (0, half and full rates). Biochar did not affect microbial biomass C or N, mycorrhizal infection, or alkaline phosphomonoesterase activities, but acid phosphomonoesterase activities, water‐soluble P, Mehlich‐3 Mg, plant height, aboveground and root biomass, and root diameter were greater with 10 Mg/ha than with no biochar. Root length, volume, root tips and surface area were greatest in the fully fertilized soil receiving 10 Mg/ha biochar compared to all other treatments. The 10 Mg/ha biochar application may have improved plant access to soil nutrients by promoting plant growth and root structural features, rather than by enhancing mycorrhizal infection rates.     

Effects of mycorrhizal inoculation of shrubs from Mediterranean ecosystems and composted residue application on transplant performance and mycorrhizal developments in a desertified soil

Arbuscular mycorrhizal inoculation and composted residue application are being assayed to aid restoration of desertified areas under Mediterranean climate. The particular objective of the present study was to assess the short-term (8 months) effects on the initial stages of plant performance and on mycorrhizal propagule release, key factors to decide further developments in the restoration process. Mycorrhizal inoculation, with Glomus intraradices, was practised during nursery production of representative shrub species from Mediterranean ecosystems and composted residues were added to soil before transplanting to a desertified area in southern Spain. Pistacia lentiscus, Rhamnus lycioides, Olea europaea subsp. sylvestris and Retama sphaerocarpa, key species from the natural succession in the target area, were the test plants. Mycorrhizal inoculation, and in some cases compost addition, improved the ability for nutrient acquisition by plants upon transplanting in the field. The number of "infective" mycorrhizal propagules was higher in soil around mycorrhiza-inoculated shrubs than that around the corresponding non-inoculated controls. The organic amendment significantly increased propagule production in the rhizosphere of mycorrhiza-inoculated plants. The number of mycorrhizal spores was relatively low in soil around transplants, being hardly affected by treatments. Only three distinguishable glomalean spore morphotypes were found, belonging to the species Glomus geosporum, G. contrictum and Scutellospora calospora, with very few unidentified spores, corroborating the low diversity in degraded ecosystems. An increased development of the extramatrical AM mycelium was found in soil around the roots of the four mycorrhiza-inoculated test plants, probably the main source of AM fungal propagules in the ecosystem at this stage of plant development. In conclusion, the tailored AM inoculation assayed was functioning under field conditions to enhance nutrient acquisition by the target indigenous shrubs and, in interaction with organic amendments, promoted mycorrhizal propagule production in soil, critical factors to benefit further stages of the revegetation process.     

Susceptibility of humic acids from soils with various contents of metals to microbial utilization and transformation

Humic acids (HAs) from a pseudogley soil with various metal contents were added as supplemental sources of nutrients, or as the sole sources of carbon or nitrogen, to aerobic cultures of complex microbial populations indigenous to the same individual soils. Depending on nutrient conditions in the individual cultures and origin of HAs, between 44% and 67% of the added HAs were utilized. The lowest utilization rate was obtained for HAs from soil heavily contaminated with Mg. The overall carbon mineralization in the microbial cultures was significantly reduced in the presence of HAs. Simultaneously, the formation of microbial biomass was enhanced up to 261%. Variovorax (Alcaligenes) paradoxus, Pseudomonas fluorescens, and a yeast Cryptococcus sp. have been identified as the dominant microbial species utilizing HAs. The individual HA preparations re-isolated from the microbial cultures exhibited distinct changes in elemental and structural characteristics. Diminished contents of ash and alterations in infra-red absorptions indicated a splitting of organic and mineral components in HAs exposed to microbial activities.     

Common Chicory Performance as Influenced by Iron Concentration in the Nutrient Solution

An experiment was carried out from February 25 till April 10 of 2010 at the Jaboticabal campus of the Paulista State University (UNESP), state of São Paulo, Brazil, viewing to find out which would be the optimum and the phytotoxic levels of iron in the nutrients solution for common chicory (Cichorium intybus) plants. Iron concentrations in the nutrients solution were of 0.9, 2.7, 8.3, and 25 mg L^?1. These treatments were replicated 4 times and the experimental units were distributed according to a randomized complete block design. The nutrient film hydroponic technique (NFT) was used. Growth parameters such as plant height and number of leaves as well as reproductive parameters such as green and dry mass production were evaluated. The optimal concentrations were found to be between 2.7 and 8.3 mg L^?1 of iron in the nutrients solution. The concentration of 25 mg L^?1 caused toxicity, although no visual sign of iron in excess was observed.     

Broiler Litter as a Sole Nutrient Source for Cotton: Nitrogen,Phosphorus, Potassium,Calcium, and Magnesium Concentrations in Plant Parts

Abstract

The ability of poultry litter to support plant growth by supplying essential plant nutrients in the absence of other sources of the nutrients has not been studied thoroughly. The objectives of this research were to (1) determine the ability of poultry litter, as the sole nutrient source, to provide macronutrients and support growth of cotton (Gossypium hirsutum L.) (2) evaluate the distribution of these nutrients within the different plant parts, and (3) estimate the efficiency with which these nutrients are extracted by cotton. The research was conducted in plastic containers filled with a 2:1 (v/v) sand:vermiculite growing mix under greenhouse conditions. The treatments included broiler litter rates of 0, 30, 60, 90, or 120 g pot^?1 with or without supplemental Hoagland's nutrient solution. Broiler litter supplied adequate amounts of the macronutrients nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) and supported normal growth of cotton. Tissue nutrient analysis showed that the concentration of N, P, K, and Mg in the upper mainstem leaves was within published sufficiency ranges for cotton growth. Evaluation of the N distribution indicated that the cotton plant partitions N to reproductive parts when faced with deficiency of this nutrient and favors allocating N to new leaf growth once the requirement for reproductive growth is met. The partitioning of P was similar to that of N but less distinct. Cotton extracted Mg and K with greater efficiency (up to 58%) than the other nutrients and stored these nutrients in older leaves. The extraction efficiency of N ranged between 21% at 120 g pot^?1 litter and 27% at 30 g pot^?1 litter. Phosphorus was the most poorly extracted nutrient, with only 16% of the total applied P extracted when 30 g pot^?1 litter was applied and only 6% extracted at the higher litter rates. This suggests that the same problem of P buildup that has been reported in soils under pasture may also occur when poultry litter is repeatedly applied to the same soil planted to cotton. These results show that broiler litter not only supplied enough N but also supplied the four other macronutrients (P, K, Ca, and Mg) in amounts sufficient to support normal cotton growth. This research implies that poultry litter can effectively substitute for several fertilizers to meet crop macronutrient (N, P, K, Ca, and Mg) needs in soils deficient in any or all of these nutrients.