Physico‐geochemical and mineral composition of neem tree soils and relation to organic properties

Abstract

The Neem tree, the oil of which has a long history of pesticide, fertilizer and medicinal use in India, has been studied extensively for its organic compounds. Here we present a physical, mineralogical and geochemical database resulting from the analyses of two Neem soil profiles (epipedons) in India. Neem tree derivatives are used in the manufacture of a variety of products, from anti‐bacterial drugs and insecticides to fertilizers and animal feeds. A preliminary geochemical and mineralogical analysis of Neem soils is made to explore the potential for chemical links between Neem tree derivatives and soils. Physical soil characteristics, including colour, texture and clay mineralogy, suggest the two pedons formed under different hydrological regimes, and hence, are products of different leaching environments, one well‐drained site, the other poorly drained. Geochemically, the two Neem soils exhibit similarities, with elevated concentrations of Th and rare earth elements. These elements are of interest because of their association with phosphates, especially monazite and apatite, and the potential link to fertilizer derivatives. Higher concentrations of trace elements in the soils may be linked to nutritional derivatives and to cell growth in the Neem tree.

Plant Organic Matter Really Matters: Pedological Effects of Kūpaoa (Dubautia menziesii) Shrubs in a Volcanic Alpine Area, Maui, Hawai’i

“…Soil color, per se, normally has little pedological relevance, but it may indicate accumulation of humified organic matter [86,98]. Many organic compounds can also coat mineral grains, influencing their color [100]. As color is not easily amenable to standard statistical tests [101], an alternative analysis method was devised [34,35].…”

Evaluation of nematicidal potential of neem sawdust against Meloidogyne arenaria on eggplant

“…NSD has been proved to be more effective than other plant-derived sawdust concerning nematode control (22). As apart from containing micro and macronutrients it also enriches the soil by way of im-proving the physico-chemical properties such as porosity, pH, Cation exchange capacity (CEC) and water holding capacity (WHC) of the soil thus can be used as a soil improver (27). The main objectives of the present work are to apply the NSD in different concentrations to the field soil to evaluate its potential as a nematicide on eggplants.…”