Potassium fertilization and soil diagnostic criteria for forage corn (Zea mays L.) production contributing to lower potassium input in regional fertilizer recommendation

Abstract

Effective soil diagnostic criteria for exchangeable potassium (Ex-K) combined with inorganic potassium (K) application rates were developed to lower K input in forage corn (Zea mays L.) production using experimental fields with different application rates and histories of cattle manure compost. Two corn varieties, ‘Cecilia’ as a low K uptake variety and ‘Yumechikara’ as a high K uptake variety, were selected from among 20 varieties and tested to make diagnostic criteria for K fertilization applicable to varieties with different K uptakes. The K uptakes increased from 96 to 303 kg K ha^?1 for ‘Cecilia’ and from 123 to 411 kg K ha^?1 for ‘Yumechikara’ with increasing Ex-K content on a dry soil basis from 0.11 to 0.92 g kg^?1 with no inorganic K fertilizer application. The K uptake by corn for achieving the target dry matter yield of 18 Mg ha^?1 was estimated to be approximately 200 kg K ha^?1 in common between the two varieties. Yields of both varieties achieved the target yield at an Ex-K content of approximately 0.30 g kg^?1 with no K fertilization, although ‘Yumechikara’ reached the target yield at a lower Ex-K content. At the low Ex-K content of 0.1 g kg^?1, inorganic K fertilizer application at 83 kg K ha^?1 was needed to gain the target yield, and apparent K recovery rate for K fertilizer was calculated to be 70% for both varieties. The K uptakes for gaining the target yield by the K fertilization were lower than that by soil K supply. Based on these results, diagnostic criteria of Ex-K and inorganic K application rates were set up as follows: at an Ex-K content of < 0.15 g kg^?1, inorganic K fertilizer is applied at 83 kg K ha^?1 (100 kg ha^?1 as potassium oxide (K₂O) equivalent); at an Ex-K content of 0.15–0.30 g kg^?1, the application rate is reduced to 33 kg K ha^?1 (40 kg K₂O ha^?1); at an Ex-K content of ≥ 0.30 g kg^?1, inorganic K fertilizer is not applied because of sufficient K in the soil. Additionally, we propose that cattle manure compost be used to supplement soil K fertility.     

NITROGEN NUTRITION ON LEAF CHLOROPHYLL,CANOPY REFLECTANCE,GRAIN PROTEIN AND GRAIN YIELD OF WHEAT VARIETIES WITH CONTRASTING GRAIN PROTEIN CONCENTRATION

Wheat cultivars (‘AC Barrie’, ‘Brook Field’, ‘Hoffman’, and ‘Norwell’) with different protein concentrations were compared under four nitrogen (N) levels (0, 50, 100 and 150 kg ha^?1) in an environment-controlled greenhouse, and the same experiment with an additional N level (200 kg N ha^?1) was repeated in the field in 2007. In the greenhouse experiment, application of 100 kg N ha^?1 resulted in significantly greater grain yield due mainly to higher number of grains per spike and heavier mean grain weight; in the field study, the 150 kg N ha^?1 treatment produced the greatest yield (P<0.01) primarily due to more number of grains per spike. Crude grain protein percentage was increased significantly with each increment of N up to the highest level; however, protein yield (kg ha^?1) increased significantly with fertilizer up to 150 kg N ha^?1. Leaf chlorophyll contents were increased linearly with increment of N levels up to 150 kg ha^?1 both in the greenhouse and field trials while leaf area indices continued to increase up to the highest application rate (200 kg N ha^?1). Canopy reflectance, expressed as normalized difference vegetation index (NDVI), attained maximum value with 150 kg N ha^?1 in the field experiment. Among the varieties tested, “Hoffman” out-yielded other three varieties due to heavier grain weight. Although highest grain and/or plant crude protein content were recorded in ‘AC Barrie’, it was the variety ‘Hoffman’ that produced the highest total protein (kg ha^?1) with largest NDVI and leaf area index (LAI) values.     

Balanced fertilization and bioregulators: enhancing productivity and profitability of wheat (Triticum aestivum)

A field experiment was conducted during the winter seasons between 2004 and 2006 to assess the role of balanced fertilization and bioregulators (foliar-applied brassinosteroid 0.5 mg I^?1, thiourea 1000 mg I^?1 and kinetin 10 mg I^?1) in enhancing the productivity of wheat. Conjoint application of NPKSZn (120 kg N, 40 kg P₂O₅, 30 kg K₂O, 40 kg S, 5.5 kg Zn ha^?1) recorded maximum improvements in yield attributes and significantly out-yielded all the fertilization treatments with 14.90, 4.97 and 6.39% increments in grain yield compared with NPK, NPKS and NPKZn treatments, respectively. Nutrient (N, P, K, S, Zn) content and uptake were also improved significantly with balanced fertilization. Among the bioregulators, application of 0.50 mg I^?1 brassinosteroid recorded maximum increments in grain yield (14.10%), followed by 10 mg I^?1 kinetin (12.31%) and 1000 mg I^?1 thiourea (9.92%), over control (4.99 t ha^?1). Bioregulators significantly enhanced the uptake of nutrients (N, P, K, S, Zn) over control. NPKSZn treatment also gave the maximum net return (Rs. 51,209 ha^?1). Among the bioregulators, brassinosteroid provided the maximum net return (Rs. 47,292 ha^?1) and benefit:cost (B:C) ratio (3.37) followed by thiourea (Rs. 45,500 ha^?1 and 3.35). Kinetin also provided yield advantage, however, it gave a significantly reduced B:C ratio compared with control.     

Optimal Management Practices for Nitrogen Application in Corn Cultivated During Summer and Fall in the Tropics

Optimal management practices for nitrogen (N) fertilization is well defined for corn (Zea mays) cultivated during summer (“summer” corn), but not for corn cultivated during the fall (“fall” corn) in the tropics. Two experiments were carried out to evaluate N rates (50, 100, 200, and 300 kg N ha^?1), N application timing (pre-planting – PP, V2–V3, and V5–V6) and N split application, once (at PP, V3, and V6), two (at V3+ V6) and three times (at PP+ V3+ V6) in corn cultivated during summer (2014/2015) and fall (2015/2016). Data on corn grain yield (CGY), weight of 1000-grains, leaf N content and values of soil-plant analyses development (SPAD) were collected and analyzed using univariate, multivariate (principal component analysis, PCA) and regression analysis. Results showed that corn growth was affected by N rates and splitting. Corn cultivated during summer presented higher CGY and weight-1000 g than corn cultivated during the fall. The highest yields were obtained with higher N rates on “summer” corn (125 kg N ha^?1) than “fall” corn (50 kg N ha^?1). Split N-application at vegetative growth stages, V3+ V6, or PP+ V2+ V6, provided higher yields for “summer” corn, while only PP application was a reliable period of N fertilization for “fall” corn. The finding is that corn cultivated during the fall presented a lower response to N and no obvious advantages to split N fertilization when compared to corn cultivated during summer. These optimal management practices for N fertilization in corn production in the tropics depend on soil water availability.     

BORON NUTRITION OF PEANUT GROWN IN BORON-DEFICIENT CALCAREOUS SOILS: GENOTYPIC VARIATION AND PROPOSED DIAGNOSTIC CRITERIA

Field studies were conducted to assess boron (B) requirement, critical concentrations in diagnostic parts based on yield response curves and genotypic variation by growing three peanut (Arachis hypogaea L.) cultivars (‘Golden’, ‘BARD-479’, ‘BARI-2000’) on two B-deficient calcareous soils. Boron application significantly increased pod yield of all the cultivars over control. Maximum pod yield increases were: ‘Golden’, 16?23%; ‘BARD-479’, 21?27%; and ‘BARI-2000’, 25?31%. The cultivars varied in B efficiency and cv. ‘Golden’ was the most B efficient (81?86%) while cv. ‘BARI-2000’ was the least efficient (76?80%). Boron requirements for near-maximum (95%) dry pod yield were 0.65 kg ha^?1 for ‘Golden’, 0.75 kg ha^?1 for BARD-479 and 0.80 kg ha^?1 for BARI-2000. Critical B concentrations in shoots and seeds were: ‘Golden’, 33 mg kg^?1 and 26 mg kg^?1; ‘BARD-479’, 38 mg kg^?1 and 31 mg kg^?1; and ‘BARI-2000’, 42 mg kg^?1 and 33 mg kg^?1.     

Phosphorus Fertilization Impacts on Corn Yield and Soil Fertility

Optimization of phosphorus (P) fertilization is important for balancing soil fertility especially in vertisol to support economic crop production. The objective of the study was to determine the impact of P fertilization (1998 to 2014) on crop yield and nutrient uptake, and soil fertility under continuous annually tilled corn (Zea mays L.)-wheat (Triticum aestivum L.) system in semi-arid Mediterranean conditions. The study was conducted on Arik clay (isohyperthermic, fine clay Typic Haploxerert) using randomized complete block design with four replications for each treatment at the research farm of the Dept. of Soil Science and Plant Nutrition, Çukurova University, Adana, Turkey. P fertilizer at 0, 50, 100, 200 kg P₂O₅ ha^?1 as triple superphosphate (TSP), respectively was applied a week before planting corn. Results showed that increasing P fertilization rates significantly decreased the number of mycorrhizal spores associated with corn roots. Similarly, a 10% decrease in corn root mycorrhizal colonization was observed with 200 kg P₂O₅ ha^?1 fertilization. In the control treatment, corn yield was 4.3 Mg ha^?1 as compared to 5.6, 5.7 and 6.1 Mg ha^?1 in 50, 100 and 200 kg of P₂O₅/ha, respectively. The relationship between P fertilization and relative yield showed that more than 95% of the corn yield was produced when P applied at 100 kg P₂O₅ ha^?1. While P fertilization significantly increased the leaf N, P, and K contents but decreased the leaf Zn, Fe and Mn contents, as compared with the control. However, P fertilization did not consistently affect the grain N and P contents. Both physiological efficiency- and agronomic efficiency of P fertilization have shown a significant non-linear increase than that of the control. Total organic C (TOC) and total N (TN) concentrations were more than 34 and 26% higher in 100 and 200 kg P₂O₅ ha^?1rates as compared with the control. Likewise, available P (AP), manganese (Mn) and zinc (Zn) concentrations increased with an increase in P fertilization rates. The AP, Mn and Zn contents significantly stratified by P fertilization. Our results suggested that 100 kg P₂O₅ ha^?1 is optimum to sustain Vertisol fertility for supporting economic corn production in the Mediterranean climates of Turkey.     

Nitrogen Leaching Of Spring Wheat Genotypes (Triticum Aestivum L.) Varying In Nitrogen-Related Traits

Efficient use of nitrogen (N) by wheat crop and hence prevention of possible contamination of ground and surface waters by nitrates has aroused environmental concerns. The present study was conducted in drainage lysimeters for three years (1998–2000) to identify whether spring wheat genotypes (Triticum aestivum L.) that differ in N-related traits differ in N leaching and to relate parameters of N use efficiency (NUE) with parameters of N leaching. For this reason two spring wheat cultivars (‘Albis’ and ‘Toronit’) and an experimental line (‘L94491’) were grown under low (20 kg N ha^?1) and ample N supply (270 kg N ha^?1). The genotypes varied in parameters of NUE but not in N leaching. Grain yield of the high-protein line (‘L94491’) was, on average, 11% lower than that of ‘Toronit’ but among genotypes had significantly higher N in the grain (%), grain N yield, and N harvest index. Nitrogen lost through leaching was considerably low (0.42–0.52 g m^?2) mainly due to low volume of percolating water or the ability of the genotypes to efficiently exploit soil mineral N. There were no clear relationships between N-related genotype traits and N leaching, but across all treatments significantly negative correlations between volume of leachate and the amount of N in the total biomass and grain N yield existed.     

Nutrients management strategies to improve yield and quality of sugar beet in semi-arid regions

The objective of this study was to evaluate the effects of organic and inorganic fertilizers on the yield and quality of sugar beet genotypes (Beta vulgaris L.). Therefore, a field trial was carried out in Peshawar, Pakistan, during the winters in 2012–2013. The field experiment was conducted in a randomized complete block design with split plots, having three replications. Fertilizer treatments (control, composted manure Higo Organic Plus at 5 t ha^?1, Maxicrop Sea Gold seaweed extract at 5 L ha^?1, farm yard manure at 10 t ha^?1, inorganic nitrogen–phosphorus (NP) at 90:60 kg ha^?1, NP at 120:90 kg ha^?1 and NP at 150:120 kg ha^?1) were allotted to main plots, while genotypes (Sandrina, Serenada and Kawe Terma) were allotted to the sub-plots. Plots treated with the application of NP at 120:90 kg ha^?1 produced the highest beet yield (76.4 t ha^?1) and sugar yield (11.1 t ha^?1), and had the second highest polarizable sugar content (14.52%) and more economic return (Rs. 553,000 per hectare) as compared to control plots. Sugar beet genotype Serenada had significantly higher beet yield (55.5 t ha^?1) and sugar yield (7.9 t ha^?1) and a higher economic return (Rs. 380,000 per hectare) than the other genotypes. Sugar beet genotype Serenada supplied with NP at 120:90 kg ha^?1is recommended for the general cultivation in the agro-climatic conditions of Peshawar valley.     

Nitrolimigation: A Nutrient-in-Water Resource for Sustainable Crop Production on ‘Acid Sands’ of Southern Nigeria

The effects of a low-external-input soil fertility enhancement solution – hereafter termed ‘nitrolimigation’ were examined, as a preferred technique of applying nitrogen and calcium in the “Acid Sands” soils of southern Nigeria. Two types of nitrogenous fertilizer sources [urea and liquid pig manure (LPM)] and two types of lime {limestone (CaCO₃) and hydrated lime [Ca(OH)₂]} were used both in greenhouse and in field experiments at varying levels: Urea [CO (NH₂)₂] 0, 40, 50, 80, 100, 120, and 150 kg ha^?1; lime 0, 0.1, 0.3, 0.5, 1.0, 5.0, and 10.0 metric tonnes per hectare (t ha^?1) and LPM 0, 30, 60, 90, and 120 t ha^?1. The rates were arranged factorially and laid out in randomized complete block design (RCBD). The results indicated that combining lime at 9 t ha^?1 and LPM at 90 t ha^?1 in irrigation water had significant (P < 0.01) positive effects on the fertility status of the “Acid Sands” soils and growth of okra- Abelmoschus esculentus, the test crop. When urea was combined with hydrated lime, it reduced acidity and provided nutrient balance in the Acid Sands of Calabar. Total nitrogen was significantly (P < 0.01) boosted from 0.05 to 0.11%, base saturation (BS) from 46 to 62%, and exchange acidity was reduced from 2.93 to 1.35 cmol kg^?1. Combining urea (46-0-0) at 80 kg ha^?1 with lime (CaCO₃) at 5 t ha^?1 raised the soil pH from 4.4 to 7.1. Exchange acidity was reduced from 0.8 cmol kg^?1 to a negligible value, but electrical conductivity was improved from 170.7 to 291.9 μS cm^?1. When LPM and lime were combined, organic carbon was increased from 2.75 to 2.93%, BS was increased from 46.72 to 75.19%, and pH was raised from 6.0 to 6.73. Plant height was increased from 9.5 to 16.9 cm while mean number of leaves was also increased from 5.6 to 6.3 only with lower level of lime (3 t ha^?1) and LPM at 90 t ha^?1. Of the nitrogen and calcium sources, LPM and limestone were better at 120 t ha^?1 and 9 t ha^?1, respectively, to offset soil acidity, boost nutrient availability, and provide balanced nutrition to arable crops grown on the “Acid Sands” of southern Nigeria.     

Long-Term Tillage,Straw Management,and Nitrogen Fertilization Effects on Organic Matter and Mineralizable Carbon and Nitrogen in a Black Chernozem Soil

Soil, crop, and fertilizer management practices may affect quality of organic carbon (C) and nitrogen (N) in soil. A long-term field experiment (growing barley, wheat, or canola)was conducted on a Black Chernozem (Albic Argicryoll) loam at Ellerslie, Alberta, Canada, to determine the influence of 19 years (1980 to 1998) of tillage [zero tillage (ZT) and conventional tillage (CT)], straw management [straw removed (S_Rem) and straw retained (S_Ret)], and N fertilizer rate (0, 50, and 100 kg N ha^?1 in S_Ret and 0 kg N ha^?1 in S_Rem plots) on macro-organic matter C (MOM-C) and N (MOM-N), microbial biomass C (MB-C), and mineralizable C (C_min) and N (N_min) in the 0- to 7.5-cm and 7.5- to 15-cm soil layers. Treatments with N fertilizer and S_Ret generally had a greater mass of MOM-C (by 201 kg C ha^?1 with 100 kg N ha^?1 rate and by 254 kg C ha^?1 with S_Ret), MOM-N (by 12.4 kg N ha^?1 with 100 kg N ha^?1 rate and by 8.0 kg N ha^?1 with S_Ret), C_min(by 146 kg C ha^?1 with 100 kg N ha^?1 rate and by 44 kg C ha^?1 with S_Ret), and N_min(by 7.9 kg N ha^?1 with 100 kg N ha^?1 rate and by 9.0 kg N ha^?1 with S_Ret)in soil than the corresponding zero-N and S_Rem treatments. Tillage, straw, and N fertilizer had no consistent effect on MB-C in soil. Correlations between these dynamic soil organic C or N fractions were strong and significant in most cases, except for MB-C, which had no significant correlation with MOM-C and MOM-N. Linear regressions between crop residue C input and mass of MOM-C, MOM-N, C_min, and N_min in soil were significant, but it was not significant for MB-C. The effects of management practices on dynamic soil organic C and N fractions were more pronounced in the 0- to 7.5-cm surface soil layer than in the 7.5- to 15-cm subsoil layer. In conclusion, the findings suggest that application of N fertilizer and retention of straw would improve soil quality by increasing macro-organic matter and N-supplying power of soil.     

Phosphorus Use Efficiency in Upland Rice Genotypes Under Field Conditions

Phosphorus (P) deficiency is one of the most yield limiting factors for crop production in South American soils. Upland rice (Oryza sativa L.) is an important crop in South American cropping systems, including Brazil. A field experiment was conducted with the objective to evaluate 20 upland rice genotypes for phosphorus (P) use efficiency. The P rate used was low (0 kg P ha^?1) and high [87 kg P ha^?1 or 200 kg phosphorus pentoxide (P₂O₅) ha^?1]. Plant height, shoot dry weight, grain yield, panicle number, 1000 grain weight, spikelet sterility, and grain harvest index were significantly influenced by P and genotype treatments. The P X genotype interaction was significant for grain yield, indicating that genotypes responded differently under two P rates. Overall, grain yield increased by 12% with the addition of P fertilization. Based on grain yield efficiency index, genotypes were classified into efficient, moderately efficient, and inefficient group. The genotypes that were classified as efficient in P use were BRA032048, BRA042094, BRA02601, BRA032051, BRA032033, BRA052015, BRA042156, BRA01600, BRA01506, BRA052023 and BRA042160. The inefficient genotypes in P us efficiency were BRS Primavera, BRA052045, BRA01596, and BRS Sertaneja. Grain harvest index had a significant positive association with grain yield and spikelet sterility had a significant negative association with grain yield, as expected. Average, P-use efficiency of five genotypes was about 17 kg kg^?1 (kg grain yield per kg P applied).     

Response of sunflower to potassium and magnesium fertilizers in calcerous soils in central Anatolia of Turkey

This research was carried out to determine the effects of potassium [0, 40, 80, 120 kg potassium oxide (K₂O) ha^?1] and magnesium (0, 20, 40, 60 kg magnesium oxide (MgO) ha^?1) applied into soil separately and together on the grain yield and yield components of sunflower for oil grown in two farmer fields in the semi-arid Central Anatolia in 2009 and 2010. The experiments were set as factorial experiment design in randomized blocks and 4 replicates. Potassium and Mg-fertilizers were used in the single time into base in the sowing. According to the results, K application in the increasing doses increased yield components more than that of Mg. Together giving of the K and Mg in certain combinations took the yield components to maximum levels. The highest grain yields were obtained by the K₄₀Mg₄₀ in the first year (7313 kg ha^?1) and by the Mg₆₀ in the second year (6510 kg ha^?1).     

Foliar phosphorus fertilization of common bean complementing phosphate fertilization at sowing

The objective of this study was to evaluate the response of common bean plants to phosphorus (P) applied to the leaves at different growth stages, as a complement to phosphate fertilization at sowing. The experiment followed the 2 × 7-factor randomized block design (RBD) with four replicates. The first factor was fertilization with P at the base with 60 and 120 kg ha^?1 of phosphorus pentoxide (P₂O₅). The second factor was the times and doses of P applied to the leaves: 0.5 or 1 kg ha^?1 of P₂O₅, at the V3 phenological stage; parceled in the following manner: 20% in V3, another 40% in R5 and 40% in R6, or 50% in R5 and 50% in R6; and one treatment with no P₂O₅ application to the leaves. P-based foliar fertilization increased P content in the grains of plants grown in soils with greater P availability. The lower common bean biomass production under scarce P availability was minimized by the foliar fertilization, as well as its productivity when 1 kg ha^?1 of P₂O₅ was applied to the leaves, 50% in the R5 phenological stage and 50% in R6. The highest productivity was obtained with the application of 0.5 kg ha^?1 of P₂O₅ to the leaves in the V3 phenological stage with the 120 kg ha^?1 dose at the base.     

Use of Treated Wastewater as Fertilization and Irrigation Amendment in Pot-grown Processing Tomatoes

ABSTRACT

Plants of tomato cultivar ‘TITANO M’ were grown under glasshouse conditions, in plastic pots filled with the upper (Ap, Soil A) and the underlying horizons (Bt, Soil B) of an Alfisol from central Greece in a randomized complete block design. Four treatments were utilized: no fertilization and irrigation with distilled water (C), irrigation with wastewater without fertilization (W), complete fertilization (110 kg N ha^?1, 150 kg P₂O₅ ha^?1, 150 kg K₂O ha^?1) and irrigation with distilled water (CF), complete fertilization and irrigation with wastewater (WF) each replicated four times. The results showed that wastewater significantly increased electrical conductivity (EC), exchangeable sodium percentage (ESP), exchangeable magnesium (Mg), and extractable zinc (Zn). A three-fold increase of above ground biomass (AGB) compared to C treatment was recorded in Soil A. Photosynthates allocation to AGB and water use efficiency (WUE) were promoted by effluent application. Wastewater could be a water source for agriculture under water limited conditions substituting partially for inorganic fertilization.     

Nitrogen Rate Influence on Pearl Millet Yield,Nitrogen Uptake,and Nitrogen Use Efficiency in Nebraska

Abstract

Pearl millet is a potential dryland crop for Nebraska. Experiments were conducted in eastern Nebraska in 2000, 2001, and 2002, and in western Nebraska in 2000 and 2001. The objectives were to determine optimum nitrogen (N) rate, N uptake, and N use efficiency (NUE) for pearl millet. The hybrids “68×086R” and “293A×086R” and N rates of 0, 45, 90, and 135 kg N ha^?1 were used. Hybrids had similar yield, N uptake and NUE responses. In western Nebraska in 2000, pearl millet yield response to N rate was linear, but the yield increase was only 354 kg ha^?1 to application of 135 kg N ha^?1. In eastern Nebraska, pearl millet response to N rate was quadratic with maximum grain yields of 4040 in 2001 and 4890 kg ha^?1 in 2002 attained with 90 kg N ha^?1. The optimum N rate for pearl millet was 90 kg N ha^?1 for eastern Nebraska. For western Nebraska, drought may often limit pearl millet's response to N fertilizer.     

Identification of Minimum Data Set Under Balanced Fertilization for Sustainable Rice Production and Maintaining Soil Quality in Alluvial Soils of Eastern India

The scarcity of non-renewable fertilizers resources and the consequences of climate change can dramatically influence the food security of future generation. Introduction of high yielding varieties, intensive cropping sequence and increasing demand of food grains day-by-day, application of recommended dose of fertilizers could not fulfill our targets due to outdated fertilizers recommendations are yet in practice. It not only alters soil quality, nutrient balance, microbial and enzymatic ecology but also affected productivity and sustainability of rice in Gangetic alluvial soils of India. The effect of fertilizers application based on “fertilizing the soil versus fertilizing the crop” which insure real balance between the applied and available soil nutrient is urgently needed. Hence, the present study was conducted during three consecutive crop seasons (2010, 2011, and 2012) to assess the effect of imbalance and balance fertilization based on initial soil test values and targeted yields, and to determine the effect of farmyard manure (FYM) when superimposed with balanced fertilizers on identification of minimum data set for the development soil quality, nutrient acquisition, and grain yield of rice. The six fertilizer treatments were laid out in a randomized block design with three replications. The treatments were: T₁-control (no fertilization), T₂-farmyard manure @ 5 t ha^?1, T₃-farmers practice (60:30:30 kg N:P₂O₅:K₂O ha^?1), T₄-precise application of mineral fertilizers based on initial soil test values (77:24:46 kg N:P₂O₅:K₂O ha^?1) for targeted grain yield of 4.0 t ha^?1, T₅-precise application of mineral fertilizers based on initial soil test values (74:23:43 kg N:P₂O₅:K₂O ha^?1) plus FYM (5 t ha^?1) for targeted grain yield of 4.0 t ha^?1 and T₆-precise application of mineral fertilizers based on initial soil test values (135:34:65 kg N:P₂O₅:K₂O ha^?1) for targeted rice grain yield of 5.0 t ha^?1. Result revealed that the targeted rice grain yield of 4.0 and 5.0 t ha^?1 was achieved in T₄ and T₆ treatments with 1.59% (4.06 t ha^?1) and –3.40% (4.83 t ha^?1) deviations, respectively. T₄, T_5, and T₆ significantly increased crop growth, nutrient uptake, available P (P_a) and K (K_a) and augmented rice grain yield by 10.6, 20.2 and 31.6%, respectively, over T₃. Microbial biomass carbon, soil respiration and enzymatic activity were enhanced significantly in T₅ as compared to T₆. Highest soil quality index was found in T₅ (0.95) followed by T₆ (0.90) and, lowest was in T₁ (0.63). The contribution of minimum data set (MDS) toward the SQI was in the descending order of ALP (30.6%) > SOC (21.5%) > K_a (11.3%) > PSM (9.68%) > N_a (8.51%). Overall, rice yield and soil quality was improved by using balance fertilization based on fertilizing the crop Vs fertilizing the soil in alluvial soils of India.     

Agronomic performance and grain quality of sesame (<Emphasis Type="Italic">Sesamum indicum</Emphasis> L.) landraces and improved varieties grown in a Mediterranean environment

Sesame seeds are an excellent food and non-food raw material, for which there is a consolidated deficit in Italy and in other European Union countries. For this reason, a 2-years experiment was conducted in Sicily to compare the agronomic performance (phenology, morphological and productive traits) and grain quality (oil and its main constituents, protein of defatted flour, fibre) of three landraces, one of Turkish origin and two Sicilian (“Ispica” and “Modica”), and two improved varieties (‘Pachequino’ and ‘Yori 77’). The landraces evidenced earliness (115 days) and the greater height of insertion of first capsule (0.52 m), whereas the variety ‘Pachequino’ was the most productive (3.5 t ha^?1). Turkish and “Ispica” landraces and ‘Yori 77’ variety provided seeds with greater lipid (54 %, on average) and protein contents (44 % on defatted flour, on average). ‘Pachequino’ and both Sicilian landraces produced seeds richer in fibre fractions. As regard to oil quality, the oleic acid/linoleic acid was found balanced (about 1) for Turkish landrace, and it decreased for the other cultivars reaching the lowest value for ‘Pachequino’. “Modica” had higher quantity of unsaponifiable matter (1.98 %) in the oil, whereas ‘Yori 77’ had the maximum concentration of phytosterols (5532.8 mg kg^?1). Policosanol fraction prevailed in oil of “Ispica” (205.8 mg kg^?1). Moreover, there was variability in the fatty acid, sterol and policosanol compositions with differences among the cultivars. Research provide information to exploit sesame within agrosystems under Mediterranean climates, and may be a starting point for breeding activity to enhance crop productivity and grain quality.     

Towards sustainable production of peppermint (Mentha piperita L.) through integrated use of vermicompost and cowpea green manuring with synthetic nitrogen fertilization

A field experiment with peppermint (Mentha piperita L.) was conducted in a sandy loam (Typic ustifluvent) soil during 2007 and 2008 at Lucknow, India. Ten treatments consisting of control (no synthetic or organic nitrogen fertilization), synthetic nitrogen fertilization (SN) 75, 150 and 225 kg ha^?1 alone, vermicompost (VC) 3 t + 37.5 kg SN ha^?1, VC 6 t + 75 kg SN ha^?1 and VC 9 t + 112.5 kg SN ha^?1 and intercropping of one, two and three rows of cowpea for green manuring in combination with 50, 100 and 150 kg SN ha^?1, respectively, were evaluated in a randomized block design. Integrated use of VC 9 t with 112.5 kg SN ha^?1 produced maximum essential oil (94.3 kg ha^?1), increased the herb and essential oil yields by 104 and 89%, respectively, over control and reduced SN use by 50%, without affecting the quality of essential oil. Application of VC and intercropping of cowpea for green manuring significantly improved the organic carbon, available N, P and K content in soil over SN alone. To get sustainable production of peppermint, application of VC 9 t ha^?1 along with 112.5 kg N ha^?1 through synthetic fertilizer is recommended for light textured sandy loam soils.     

Chemical Attributes of Soil and Forage Yield of Pasture Recovered with Phosphate Fertilization and Soil Management

Extensive and semi-extensive pastures are the basis of Brazilian livestock production. However, much of it is degraded or in degradation process, with low stocking rate per area. Even with this problem, this management type is 60% and 50% of Australia’s and the United States’ production costs, respectively. In order to research alternatives for Urochloa decumbens degraded pasture recovery in an Oxisol, Stylosanthes (Stylosanthes spp.) “Campo Grande” cultivar was introduced and phosphate fertilization was applied. The experimental design was of randomized blocks, 7 × 2 × 2 factorial design, with four replicates, involving seven systems to introduction (U. decumbens control; partial desiccation with 1.5 L ha^?1 glyphosate, total desiccation with 3.0 L ha^?1 glyphosate; direct planting; scarification, harrowing, and plowing + harrowing), phosphate fertilizer presence or absence, and two evaluation periods. “Campo Grande” Stylosanthes legume introduction increased shoot dry weight (SDW) yield, except in direct planting. Phosphorus fertilization increased SDW yield only in the first period, and Stylosanthes introduction in the pasture has not changed soil chemical properties. Phosphorus (P) fertilization also provided available P and exchangeable calcium (Ca²⁺) content in the soil increase, in addition to sum of bases and cation exchange capacity increase.     

Effect of nitrogen fertilization on methane and carbon dioxide production potential in relation to labile carbon pools in tropical flooded rice soils in eastern India

In an incubation experiment with flooded rice soil fertilized with different N amounts and sampled at different rice stages, the methane (CH₄) and carbon dioxide (CO₂) production in relation to soil labile carbon (C) pools under two temperature (35°C and 45°C) and moisture (aerobic and submerged) regimes were investigated. The field treatments imposed in the wet season included unfertilized control and 40, 80 and 120 kg ha^?1 N fertilization. The production of CH₄ was significantly higher (27%) under submerged compared to aerobic conditions, whereas CO₂ production was significantly increased under aerobic by 21% compared to submerged conditions. The average labile C pools were significantly increased by 21% at the highest dose of N (120 kg ha^?1) compared to control and was found highest at rice panicle initiation stage. But the grain yield had significantly responded only up to 80 kg ha^?1 N, although soil labile C as well as gaseous C emission was noticed to be highest at 120 kg ha^?1 N. Hence, 80 kg N ha^?1 is a better option in the wet season at low land tropical flooded rice in eastern India for sustaining grain yield and minimizing potential emission of CO₂ and CH₄.