Juan Hirzel

Residual effects of poultry litter on silage maize (Zea mays L.) growth and soil properties derived from volcanic ash

Abstract Poultry litter (PL) is a cheap alternative to conventional fertilizers. The use of PL in this way also reduces the environmental problems normally associated with its disposal. The residual effect of PL may reduce the amount of fertilizer (especially N fertilizer) required by subsequent crops. This study examines the residual effects of PL (with and without additional mineral fertilizer) on the properties of a volcanic ash soil and on silage maize (Zea mays) yields in central Chile. Poultry litter and mineral fertilizer were applied in 2002–2003 and their residual effects were determined in 2004–2006. The dry matter (DM) yield, nutrient balance and apparent nitrogen recovery efficiency (ANRE) of the silage maize were determined for each season, and the soil properties were analyzed at three depths (0–20, 20–40 and 40–60 cm) at the end of the third season. Crop yield showed a positive response to all fertilizer treatments. The residual effect, the nutrient balance, N uptake and ANRE also improved with fertilizer treatment, especially with the PL treatments. The average DM yield for the PL treatments was higher than that observed using mineral fertilizer by 2.8 and 1.2 Mg ha−1 in the third and fourth years, respectively. The ANRE was generally higher in the PL treatments, although it decreased over time (12.4 and 1.7% for the last 2 years, respectively). The mean ANREs for the mineral fertilizer treatment were 4.1 and 1.6% for the same years. The results suggest that the PL treatments had an important positive residual effect in terms of N supply. This should be taken into account when planning the next crop. After two annual applications of PL, slight increases were observed in soil NO3-N at a depth of 0–20 cm, and extractable P at depths of 20–40 cm and 40–60 cm. No other soil variables were significantly affected by any of the treatments. An additional source of K was found to be necessary to maintain an adequate soil K level.

Availability of Nitrogen, Phosphorus and Potassium from Poultry Litter and Conventional Fertilizers in a Volcanic Soil Cultivated with Silage Corn

A B S T R A C T Poultry litter (PL) is an organic matter source used as soil amendment. Besides its important nutrient content, it is a cheap alternative to conventional fertilizers in crop production. The efficient use of PL also helps reduce the environmental problems normally associated with its disposal near poultry production farms. This article reports the relative effects of PL and conventional fertilizers on the availability of soil N, P and K, dry matter (DM) production and total nutrient content in silage corn (Zea mays L.). The field experiment was carried out in a soil derived from volcanic ash (Tipic Melanoxerands) of Central South Chile. Corn was grown for three seasons (2002-2005) and PL and conventional fertilizers were applied in the first two years. The residual effect of the added fertilizer sources was evaluated in the third year. DM production in the fertilized treatments was similar and fluctuated between 30.6 and 37.1 Mg ha -1 for the two years of fertilization, and between 18.9 and 20.4 Mg ha -1 for the year without addition of nutrients. The plant nutrient concentrations were similar between fertilized treatments, except for the second year, in which N and P concentrations were higher with PL. During the third year (without fertilization), N decreased in the whole plant. Soil nutrient availability was similar between fertilization sources for the three years evaluated, the higher concentration being presented in the first two years (with fertilization). These results suggest that PL is an alternative fertilizer source to conventional fertilizers.

Nitrogen Mineralization and Released Nutrients in a Volcanic Soil Amended with Poultry Litter

Optimum application rates of poultry litter (PL) spread out on the farmers field is a valuable source of available plant nutrients. The aim of this study was to compare the effect of two rates of PL and conventional fertilization (CF) on N mineralization and P, K, Zn, and Cu availability in an Andisol from Southern Chile under controlled conditions. Aerobic incubation was carried out for a 16-wk period. N mineralization rates were higher (61.5%) with the two PL treatments than with conventional fertilizer (23%). CF was associated with high N availability prior to the start of incubation and slight immobilization during the first week, perhaps due to a more rapid conversion of urea into NH4 which was then temporarily immobilized by the microbial biomass. At the start and end of the incubation period, Olsen-extractable P content was generally higher in CF. Due to the high fixation capacity of the soil studied, extractable P values were slightly increased suggesting that PL mineralization is only associated with a low risk of P contamination in volcanic soil. In PL, K, Zn, and Cu availability were higher than in CF. However, values obtained for Cu and Zn were average in relation to referential values used in agricultural soil. The results indicated that PL could be an alternative to conventional fertilizer under the conditions of the present study.

Effect of soil depth and increasing fertilization rate on yield and its components of two durum wheat varieties

Agronomic practices, climatic variables, and soil conditions are key factors in crop productivity. Although the effects of soil chemical properties and water and agronomic crop management are known, there is little information about effective soil depth and its influence on crop productivity. Since most crop fertilization systems are based on the productive potential associated with climatic conditions and chemical properties of the first 20 cm of soil depth, the objective of this study was to determine the importance of effective depth in terms of increasing fertilization rates on durum wheat ( Triticum turgidum L. var. durum) productivity. Two experiments were conducted in the 2006-2007 season in the Santa Rosa Experimental Station (71°54’ S, 36°31’ W, 220 m a.s.l.) of the Instituto de Investigaciones Agropecuarias (INIA) located in south central Chile. We used the hard wheat cvs. Llareta-INIA and Corcolen-INIA because both respond differently to soil physicochemical properties. Each cultivar was sown in sectors with different depths: 1) 0.45 m depth, silt loam on river material and 2) 1.0 m depth, loam on deep sediments. Fertilization was: 1) control without fertilization, 2) basal fertilization (BF) based on P, K, Ca, Mg, S, B, and Zn plus 90 kg N ha-1, and 3) BF plus 210 kg N ha-1. Grain yield, plant height, and number of stems m-2 were positively affected by increasing depth of soil profile. The increasing fertilization rate affected grain yield and plant height. Grain yield for cv. Corcolen-INIA had a greater response than cv. Llareta-INIA when soil depth was increased.

Effect of Split Nitrogen Applications on Durum Wheat Cultivars in Volcanic Soil

Durum wheat (Triticum turgidum L. var. durum) is an important crop for the world population and occupies a large cultivated area worldwide. New cultivars need constant improvement of their agronomic management, within which N fertilization is highlighted. Durum wheat is also important in Chile where genetic breeding and agronomic management have been developed to increase yield, industrial, and nutritional grain quality. The objective of this experiment was to determine the appropriate number of N applications during a crop cycle in a volcanic ash soil in South Central Chile. Nitrogen split applications were carried out on three durum wheat cultivars in a Melanoxerands soil during the 2003-2004 and 2004-2005 seasons. A rate of 200 kg ha -1 N was applied at different growing stages including planting, tillering, flag leaf, and heading (200-0-0-0, 100-100-0-0, 66-67-67-0, and 50-50-50-50 kg N ha -1 , respectively). The evaluated traits were grain yield, hectoliter weight, and wet gluten content. Results indicated that the use of two and three split N applications increased grain yield and wet gluten content with differences among genotypes. The best N split strategy corresponded to two and three N splits: at planting and tillering; at planting, tillering, and flag leaf, respectively.

Short-Term Effects of Poultry Litter Application On Silage Maize Yield and Soil Chemical Properties

If properly managed, poultry litter (PL) might be a good alternative to conventional fertilizers. This paper reports on a three-year field study to compare the effects of two consecutive PL and traditional mineral fertilizer applications on silage maize (Zea mays) production and soil chemical properties. The experiment was undertaken on volcanic soil in the Central-South Region of Chile. The PL was applied at doses of 10, 15 and 20 Mg ha−1, with and without mineral fertilizer to 50 m2 plots, and the outcomes compared with those obtained with two rates of nitrogen mineral fertilizer equivalent to the mid and high PL rates. Maize yield showed a positive response to all treatments, although the mean yield obtained with the PL treatments was higher than with the mineral fertilizer in the third year, in which no fertilizers were applied. The whole plant N concentration of the PL plants was significantly higher than that of the plants that received mineral fertilizer (this was the only nutrient variable for which such differences were found), but the values were not related to the amount of PL applied. After two annual applications of PL, slight increases in soil-available inorganic N and P were observed. However, the values obtained were low, highlighting the high P fixation capacity of the soil as well as its high capacity to stabilise organic matter. No other soil variables studied were significantly affected by any of the treatments.

Effect of soil cadmium concentration on three Chilean durum wheat cultivars in four environments

ABSTRACT Durum wheat (Triticum turgidum L. var durum) is a species that accumulates cadmium (Cd). Durum wheat cultivars differ in their absorption ability of Cd; therefore, identifying and selecting genetic material with low Cd accumulation reduces human exposure to this toxic element. In the present study, Cd concentration was evaluated in three Chilean durum wheat cultivars (Llareta-INIA, Corcolén-INIA, and Lleuque-INIA) grown in four Chilean locations with varying concentrations of Cd in soils. The objective of this study was to evaluate the response of these durum wheat cultivars to different doses of cadmium in terms of grain yield; Cd concentration in different plant tissues (grain, straw, roots); soil Cd concentration was also evaluated. Results show that grain yield was not affected by soil Cd; differences in Cd concentration in plant tissues were generally associated with location, cultivar, and soil Cd concentration. Grain Cd concentration in all three cultivars was classified in the low accumulation category for this metal; ‘Lleuque-INIA’ noted as having a very low accumulation.

Cadmium phytoextraction capacity of white lupine (Lupinus albus L.) and narrow-leafed lupine (Lupinus angustifolius L.) in three contrasting agroclimatic conditions of Chile

The phytoextraction process implies the use of plants to promote the elimination of metal contaminants in the soil. In fact, metal-accumulating plants are planted or transplanted in metal-contaminated soil and cultivated in accordance with established agricultural practices. The objective of the present study was to evaluate the productivity and Cd phytoextraction capacity of white lupine (Lupinus albus L.) and narrow-leafed lupine (Lupinus angustifolius L.), as well as the effect on residual Cd concentration in the soil. Both species of lupines were grown at three CdCl2 rates (0, 1, and 2 mg kg-1), under three agroclimatic conditions in Chile in 2013. In the arid zone (Pan de Azucar, 73 mm precipitation), narrow-leafed lupine production was significantly (P < 0.05) higher than white lupine (4.55 vs. 3.26 Mg DM ha-1, respectively). In locations with higher precipitation (Santa Rosa, 670 mm; Carillanca, 880 mm), narrow-leafed lupine DM production was slightly higher than in Pan de Azucar, but white lupine was approximately three times higher. Total plant Cd concentrations in white and narrow-leafed lupine increased as Cd rates increased in the three environments, but they were much higher in narrow-leafed lupine than white lupine; 150%, 58%, and 344% higher in Pan de Azucar, Santa Rosa, and Carillanca, respectively. Cadmium uptake (g Cd ha-1) and apparent recovery were also higher (P < 0.05) in narrow-leafed lupine in two environments (Pan de Azucar and Carillanca). These results suggest that narrow-leafed lupine present higher potential as phytoremediation species than white lupine.

Increasing nitrogen rates in rice and its effect on plant nutrient composition and nitrogen apparent recovery

Rice ( Oryza sativa L.) is one of the essential foods of the human diet; advances in agronomic crop management can improve productivity and profitability as well as reduce adverse environmental impacts. Nitrogen rates in Chile are generally based on crop yield without considering other agronomic factors. The objective of this experiment was to determine the effect of increasing N rates on plant nutrient composition and N apparent recovery in rice cultivated in five different locations in Chile. The five sites located in central Chile belong to one of the following soil orders: Inceptisol, Alfisol, and Vertisol; they were cropped in field conditions with ‘Zafiro-INIA’ rice fertilized with 0, 80, and 160 kg N ha-1. Whole-plant total DM, macronutrient composition, and N apparent recovery efficiency (NARE) were determined at grain harvest. Results indicate that all evaluated parameters, with the exception of K concentration, were affected by the soil used. Nitrogen rates only affected total DM production and P, K, and Mg concentrations in plants. Phosphorus and K response decreased when N was added to some soils, which is associated with its chemical properties. Magnesium concentration exhibited an erratic effect, but it wasSnot affected by the N rate in most soils. Nitrogen apparent recovery efficiency was not affected by the N rate and accounted for approximately 49% and 41% for 80 and 160 kg N ha-1, respectively. Macronutrient composition was 5.1-7.7 g N, 1.3-1.8 g P, 5.4-10.8 g K, 1.68-2.57 g Ca, and 0.81-1.45 g Mg kg-1 of total DM.

Chemical properties of volcanic soil affected by seven-year rotations

Long-term crop rotation systems can benefit soil chemical-physical properties and crop productivity. The lack of information on the effect of long-term crop rotations on soil chemical-physical properties for volcanic soils in Chile could restrict reaping real benefits, and make it difficult to take agricultural management decisions, which could lead to possible negative consequences on some soil chemical-physical properties and the environment. The development of information associated with the effect on soil chemical-physical properties with respect to long-term rotation systems and their fertilization management contribute to improving agronomic management decisions for these soils. A study was carried out to assess the effect of six rotation systems replicating fertilization management used by farmers, especially N and P application, and eventually low rates of K, Ca and Mg on soil chemical properties in a volcanic soil after 7 yr in Central South Chile. Affected chemical properties were pH, inorganic N, and available K, along with a general decrease of pH related to fertilization used, which was insufficient in Ca, K, and Mg. Moreover, this soil exhibited high P adsorption capacity (90.2 to 97.5%). Hence, crop rotations that included pasture legumes and crops with high nutrient inputs such as sugar beet (Beta vulgaris L.) generated a less negative effect on soil chemical properties. This study indicates that fertilization management in crop rotation systems must consider the input and output nutrient balances to prevent the negative effect on some soil chemical properties.