Nutrient supply from organic amendments applied to unvegetated soil, lettuce and orchardgrass

Abstract

. Nutrient supply from organic amendments applied to unvegetated soil, lettuce and orchardgrass. Can. J. Soil Sci. 86: 21-33. Organic sources of nutrients are increasingly being used in horticultural and certified organic production. The nutrient-supplying potentials of poultry manure compost (PM), feather meal (FM), alfalfa meal (AA) and vermicastings (VC) and an unamended control were measured in a growth room experiment. The amendments were applied at rates equivalent to 200, 400 and 800 kg total N ha -1 to a soil of low fertility. Nitrogen supply rates and concentrations were measured over 6 mo in unvegetated pots using PRS™ probes and KCl extraction, respectively. Biomass of lettuce (Lactuca sativa L.) and orchardgrass (Dactylis glomerata L.) and N uptake of orchardgrass were measured. Repeated measures analysis revealed significant amendment × rate × time interaction effects for N supply rate and concentration. Of total N applied, available N was 50 to 70% in the FM and PM treatments, 10 to 40% in the AA treatments, and 10% in the VC treatments. High rates of FM and PM were toxic to lettuce but produced good orchardgrass yields. VC was safe for lettuce but low N availability limited long-term orchardgrass growth. Higher application rates did not result in corresponding increases in nutrient supply. Consideration should be given to balancing the ratio of available nutrients in amendments with plant requirements. toxique pour la laitue, mais assure un bon rendement de dactyle pelotonné. Le FV est inoffensif pour la laitue, mais la faible quantité de N réduit la croissance à long terme du dactyle. Un taux d'application supérieur n'entraîne pas de hausse correspondante de l'apport de nutriments. On devrait songer à équilibrer la quantité d'éléments nutritifs disponible avec les besoins de la plante.

Nutrient release pattern from Leptic Cambisols as influenced by vermicompost and inorganic fertilizer applications

“…Similarly, the declines for pots treated with 0, 33.33, 66.67 and 100% of the recommended doses of NPK from inorganic fertilizers at this stage were 48, 51, 53 and 56%, respectively. This trend has also been reported by Hammermeister et al (2006), who reported lower soil N mineral content in the final analysis compared to the initial analysis for several treatments, suggesting loss of N with time. Similarly, Nathiya and Sanjivkumar (2015) have also found higher available nitrogen content on vegetative and flowering stage of groundnut than at postharvest stage, indicating that plants derive nutrients from soil for their growth and development leading to the depletion of soil nutrients at the late growth stages.…”

“…Even though chemical fertilizers substantially increased the available plant nutrients during the first weeks, losses arising from different factors limit the continual supply of nutrients at critical periods where plants inquire high demand for these nutrients. Reports from Hammermeister et al (2006) show that chemically fertilized plots declined in NH 4 + as sampling time continues. On the other hand, available P was high at tillering which declined later at flowering and maturity stages of rice (Lungmuana et al, 2013) compared to organic residues and manures.…”

Sweet Onion (Allium cepa L.) as Influenced by Organic Fertilization Rate: 1. Plant Growth, and Leaf and Bulb Mineral Composition

“…In a lettuce (Lactuca sativa L.) pot study, of the total N applied (200-800 kg · ha -1 ), available N over 6 months was 50% to 70% with feather meal and poultry manure compost treatments, 10% to 40% with alfalfa meal, and 10% with vermicastings. Application rates above 800 kg · ha -1 did not result in corresponding increases in nutrient supply (Hammermeister et al, 2006). Insufficient soil N availability is frequent in organic vegetable production because of unpredictable N release.…”

Assessing soil nitrogen availability in contrasting cropping systems at the end of transition to organic production

“…Compared with conventional agriculture, nutrient management in organic farming rotations can become very complex when trying to account for nutrient contributions from soil amendments, in addition to forages. Considerable efforts have been made to evaluate N availability for different types and rates of soil amendment (N'Dayegamiye et al 1997;Eghball 2000;Mkhabela and Warman 2005;Hammermeister et al 2006) and forages (Patriquin et al 1986;Griffin and Hesterman 1991). On a commercial farm, the application rates of soil amendments are also adjusted according to expected nutrient availability from previous crops in rotation and the nutrient demands of the current crop.…”

“…The amounts of N 2 fixed by leguminous crops are affected by environmental conditions (Haase et al 2007), and a large variation in fixation rates (i.e., from 40 to 240 kg N ha (1 ) has been reported (Patriquin et al 1986;Griffin and Hesterman 1991). Nitrogen availability from soil amendments can also vary depending on N source (Eghball 2000;Amlinger et al 2003;Hammermeister et al 2006), and application rate (He´bert et al 1991). Nitrogen management could be improved by quantifying the N availability from soil amendments and forages at the end of an organic transition period.…”