Evaluation of potting media for commercial nursery production of container-grown plants

Abstract

Effects of isobutylidene diurea (lBDU) , osmocote, ammonium sulphate «NH4) 2S04) , and urea fertilisers in the presence or absence of a nitrification inhibitor, 2-chloro-6-(trichloromethyl) -pyridinie ('N-serve') on the dry matter yield and nitrogen uptake of Callistephus chinensis (L.) Nees (aster) in three New Zealand commercial nursery potting media were determined. The three media were: peat-sand (P-S), peat-sand-sawdust (P-S-saw), and peatsand-soil (P-S-soil). Dipton peat was used in the main experiment and Mataura peat in the split-application experiment. In the main experiment, generally, in P-S and P-S-saw, IBDU, osmocote, osmocote and N-serve, (NH4)2S04, and urea produced significantly higher yields than did IBDU and N-serve, urea and N-serve, and (NH4)2S04 and N-serve, which contained higher concentrations of nitrogen. The reduced growth of plants was probably because of ammonium toxicity. All fertiliser treatments, including the N-serve treatment, gave similar results in the soil medium. This was attributed to high amounts of NOs-N present, reducing the toxic effect of high NRI-N regimes. Results also showed that asters could be grown equally well in all three media, provided adequate water and nutrients were present. There were, however, indications that the P-S-saw medium encouraged better root growth particularly when the fertilisers were applied as split dressings. The split application of (NH4)2S04 and also that of urea reduced growth substantially in the P-S-saw medium by rapid immobilisation of applied N. Root growth in the first 49 days was greater in the Mataura peat-based media than in the Dipton peat-based media.

Efeito do volume de tubetes e tipo de substratos na qualidade de mudas de <i>Cryptomeria japonica</i> (L.F.) D. Don.

“…O aspecto físico mais importante de um substrato, segundo HAYNES & GOH (1978), é a presença de estrutura porosa, com capacidade de estocar e suprir água para as raízes das plantas, e, ao mesmo tempo, proporcionar aeração adequada.As características químicas mais importantes são o pH e o teor total de sais solúveis, pois podem modificar o suprimento dos fertilizantes (VERDONOK, 1984). O valor do pH em água recomendado para a maioria das espécies florestais varia de 5,5 até 6,5 (SIQUEIRA, 1987).…”

Growing media, greenhouse tomato yield and Pythium root rot

“…This is also consistent with the soil dead porosity value of 0.10 cm 3 cm -3 reported by Glinski and Stepniewski (1985) for mineral soils, where gas relative diffusion tends toward zero, and with the low gas relative diffusion obtained by King and Smith (1987) for peat at air-filled porosities of 0.10 cm 3 cm -3 and below. As expected, additions of sawdust to peat improved substrate aeration properties (Haynes and Goh 1978) (Table 3). Indeed, significant quadratic relationships linked AFP and Ds/Do to the peat content in the substrate (Fig.…”

Greening the Growth: Unveiling the Impact of Compost Extract on Seed Germination and Soil-Compost Mixtures on Biomass Yield and Leaf Chlorophyll Content

“…Compost extract, an organic amendment, elevates chlorophyll content and enhances growth (Hargreaves et al, 2008). Organic manure boosts chlorophyll content in crops (Arisha and Bradisi, 1977). However, little literature is available on the effects of compost extract on germination of seeds and growth of crop seedlings.…”