Significance of Elemental Sulphur, Bio-Inoculation and Micronutrient Foliar Applications on Canola Plants Grown in A Newly Reclaimed Soil Calcareous in Nature

Document Type : Original Article

Abstract

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FIELD experiment was conducted on a slightly saline-alkaline sandy clay loam soil calcareous in nature at a Private Farm of a newly reclaimed area comprising the eastern outskirt desert zone of El-Fayoum district, El-Fayoum Governorate, Egypt during the growing winter season of 2009-2010. The main target of this study was at identifying the positive effects of applied elemental sulphur (ES, i.e., at the rates of 0, 150, 300 and 450 kg/fed, as soil application), seed bio-inoculation (PDB, i.e., P-dissolving bacteria of Bacillus megatherium var. phosphaticum) and some micronutrients (MFS, i.e., Fe, Mn, Zn and Cu in EDTA-chelated form, as foliar spray) as either solely or combined treatments on canola (Brassica napus L., Serw 4 cv.) growth parameters at early flowering stage (i.e., leaf content of chlorophyll a & b, plant height, number of branches plant-1, dry matter weight plant-1, fruiting zone length and plant nutritional status), yield (number of pods plant-1, 1000 seeds weight, seed and straw yields) and seed quality parameters (i.e., seed oil and protein contents). The associated amelioration in some soil properties (i.e., soil pH, ECe, ESP and available macro and micronutrient contents) were taking into consideration in this study.

The obtained results indicated that the experimental soil could be classified as "Typic Torriorthents, fine loamy, mixed, hyperthermic". Soil suitability class for irrigated agriculture land belongs to a moderately suitable class (S2) in both current and potential conditions as well as moderately and highly suitable classes for cultivating canola plants, respectively. Data showed also a clear response for ameliorating soil properties, i.e., soil pH, ECe and ESP values as well as soil nutritional status as a result of the applied treatments, particularly those treated with the highest rates of elemental sulphur.

The obtained data emphasized that the achieved amelioration in soil properties was positively reflected in the studied plant parameters at the different growth stages of canola. The best and achieved greatest values were associated with pants subjected to the triple combined treatment (ES x PDB x MFS) as compared to the other combined or solely ones. Further, the applied treatments display an effective role in increasing growth plant characters and nutrient contents of plant tissues at early flowering stage (85 days after sowing), which positively reflected on seed yield and its quality. In general, the values of plant parameters were optimized, for bio-inoculated and micronutrients foliated plants, with increasing the applied elemental sulphur rates up to 300 or 450 kg fed-1, with insignificant differences. In this connection, the applied S and P-dissolving bacteria were also resulted in alleviating the antagonism between P and Zn in soil solution as well as showed a synergistic relationship represents the most appropriate treatment for obtaining an optimum seed yield with high contents of protein and oil.

So that, it could be recommended that elemental sulphur, seed bio-inoculation with P-dissolving bacteria and micronutrients in EDTA-chelated forms as foliar spray should be used to alleviate the hazardous effects of either a saline soil or a calcareous in nature, which negatively affect canola seed yield and its quality. In addition, such favourable conditions should enhancecontinuous biological activity and nutrients slow release along the growth stages of canola plants, and in turn to minimize their possible losses by either leaching process or volatilization and rationalize the use of mineral fertilizers, which represents a surplus point for sustainable agriculture system. This approach represents the best strategy in agriculture field that has a long-term positive agronomic value and an effective practice of fertilization management on long-term.

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