Raafat N. Zaki and N. R. Habashy( 2011). The Role of De-oiled Seed Cakes as Organic Sources of Nutrient Applied to Sunflower and Maize Crops Grown in a Calcareous SoilResearch Journal of Agriculture and Biological Sciences, 7(1): 23-31, 2011 ISSN 1995-0748
Abstract: Two year field experimental were carried out in a calcareous soil at West Noubaria region (private farm) during summer season of 2009 and 2010 to compare the effects of full and partial applications of organic sources as rich-nutrient supplies and/or as soil conditioners, with the recommended doses of inorganic fertilizers (RDF) on growth index and yield of sunflower (Helianthus annuns) and maize (Zea mays) crops. Eleven
treatments, including: the control, 100% of (RDF), 100% of full recommended dose of nitrogen (RDN), through de-oiled seeds of Jatropha (JC), Castor seed cakes (CC), farm yard manure (FYM) and mixtures of 50 and 25% of the organic sources plus 50 and 75% of RDF, respectively, were arranged in complete randomized block design with three replicates. At the proper time, growth index, yield records, nutrient uptake, oil and
fatty acid contents were assessed on the growing crops. At the end, some soil properties (pH, organic carbon and bulk density) and soil nutrient status were also calculated. The results showed that: 1- The contrary result prevailed on organic carbon and soil bulk density, considerable decrease in soil pH was observed along the treatment variable. However, higher N, P and K content were noted for the soil treated with mixture treatments of 50:50%, followed by the single organics fertilizers at the end of experiment. The results detected on Fe, Mn and Zn soil nutrients content are quite different, revealing the performance of single organics. 2- Relative to the control, sunflower supplied with single organic sources exhibited marked effects on the measured growth criteria, except LAI. The relative comparisons between RDF and the respective organic sources showed mixed significant trends on growth and yield performances. 3- The results detected on the fertilizers mixtures proved
that the combined applications of 75% RDF plus 25% of RDN, through any of the tested organics were more superior to stimulate growth attributes and yield records than the single applications and/or rational fertilizers mixtures of 50:50%. Satisfactory results were however achieved when sunflower plants were treated with 75% RDF+ 25% RDN through JC or CC, rather than FYM. 4- The result obtained on maize crops proved that the plants provided with 50:50% fertilizers mixtures exhibited maximum response on the all measured data, followed by the single application of organics. Optional results were actually detected on yield when 50% of
RDF was incorporated with 50 % RDN, through JC. 5- The maximum N uptake in sunflower plants was clearly for the single application of RDF and the integrated fertilizers mixtures, whereas 75% of RDF was combined with 25%RDN, through JC source. Lower N uptake was noted for the plants treated with single organics, followed by the fertilizers mixture treatments of 50:50%. 6- As for N uptake trend, similar results were reported on P and K-uptake by sunflower plants. However, the results detected on nutrients uptake in maize are quite different, revealing the performance of 50:50% of fertilizers mixture. 7- In contrast to the ANUE trends, wider variations in PNUE were developed between the tested crops, being the highest for 75% RDF+25% of organic. 8- Net returns recorded were highest value in the treatment of 50% RDF+50%RDN
through JC for both sunflower and maize crops.
Keywords: (Jatropha, Castor seed cakes, Calcareous soils, Sunflower, Maize crop.)
