Nutritional composition and micronutrient status of home made and commercial weaning foods consumed in Tanzania

About 50% of young children in Tanzania suffer from protein-energyundernutrition (PEU) while more than 45% of children under the age offive suffer from various micronutrient deficiency disorders. The immediatecause of these conditions is inadequate intake and poor utilization ofnutrients, which begins in the weaning period and amplifies in thesubsequent years. This study was conducted to assess the potential of somehome made and commercial weaning foods commonly consumed in Tanzania tosupply adequate amounts of both macro- and micronutrients as recommendedin the Tanzania and FAO/WHO Codex Alimentarius Standards forcereal/milk-based weaning foods. Six types of home made weaning foods,maize, cassava, millet, sorghum and millet-sardine-peanut composite gruelsand plantain pap, and four types of commercial weaning foods, Cerelac-1,Cerelac-2, Lactogen-1 and Lactogen-2, popularly consumed in Tanzania, werechemically assayed for proximate composition, energy and mineral density.Results of the study indicated that, both the home made and commercialweaning foods were good sources of macro- and micronutrients. Whencompared with the Codex Alimentarius and Tanzania Bureau of Standardsspecifications for weaning foods, both home made and commercial weaningfoods had some shortcomings in terms of nutrient composition and energybalance. Many of the foods were low in fat, Fe, Ca, Zn and P but high incrude fiber, carbohydrate and magnesium. Ca, Fe and Zn were the mostcommon deficient macro/micronutrients in the home made weaning foods. Inspite of these shortcomings, most of the home made and commercial weaningfoods were nutritionally sound since they could provide reasonablepercentages of the recommended daily allowances for macro/micronutrientsand energy. It is suggested that, more efforts must be directed towardsincreasing the concentration of Ca, Fe and Zn in the home made weaningfoods through supplementation of the starchy staples with mineral richfoods. Meanwhile, the parents, caretakers and health workers should beeducated on the selection and preparation of nutritious, balanced weaningfoods and good weaning practices.     

SULFUR AND BORON-MAGNESIUM-ZINC COMPOUND FERTILIZER CONTRIBUTE TO THE REPRODUCTIVE GROWTH OF JATROPHA CURCAS L.

Jatropha curcas L., a native tree to Mexico and Central America, is cultivated in many counties of China as a source for biodiesel. The effects of different fertilizers on the growth of Jatropha curcas L. were studied under soil conditions of low nitrogen (N), phosphorus (P), potassium (K) and boron (B) in soil. Compared with 16N-16P-16K compound fertilizer, both sulfur (S) and a B-management (Mg)-zinc (Zn) compound fertilizer both increased the oil concentration of the seed, and promoted the reproductive growth. Only the fertilizer S increased the seed yield and the Acid value of the oil, while the B-Mg-Zn compound fertilizer declined the Acid value of the oil and induced the differentiation of female flowers. Boron-Mg-Zn compound fertilizer induced a smaller increase in the oil concentration of Jatropha curcas seed than fertilizer S and the largest increase in growth rate of trees. Moreover, Jatropha curcas showed a higher requirement of S for the reproductive phase than for its vegetative growth. Jatropha curcas may belong to the species with restricted B mobility, and B fertilizer should be sprayed as a foliar fertilizer. However, further research on the S nutrition of Jatropha curcas is required.     

COMPARATIVE STUDIES ON THE IRON AND ZINC CONTENTS ESTIMATION USING ATOMIC ABSORPTION SPECTROPHOTOMETER AND GRAIN STAINING TECHNIQUES (PRUSSIAN BLUE AND DTZ) IN MAIZE GERMPLASMS

Malnutrition arising from dietary deficiency of critically important mineral micronutrients such as iron (Fe) and zinc (Zn) is a serious problem affecting nearly half of the world's population. Screening for micronutrients rich breeding lines includes the estimation of grain micronutrient contents in the seed samples using atomic absorption spectrophotometer (AAS). Though the protocol produces precise results, it is usually costly and time consuming. The nutritionist started searching for newer methods like staining the particular plant tissue with dyes so the initial screening of among vast germplasm lines becomes easier. A set of four hundred and thirty genotypes were used in this experiment wherein the reliability and the cost effectiveness of the use of the staining method in place of the estimation using AAS was investigated. The intensity of the color developed was directly proportional to the amount of iron and zinc in the grains and were scored as 1, 2, 3, 4, and 5. The genotype ‘UBC 7’ has got the maximum level of iron (65.43 mg kg^?1) with about 64 lines is found to contain higher levels of iron. The genotype ‘UMI 421’ had the maximum level of zinc (60.15 mg kg^?1) along with ten lines showing richer zinc levels. The genotypes namely ‘UMI 1069’, ‘UMI 630’, ‘UMI 473’, ‘UMI 327’, and ‘UMI 382’ are found to be having considerably higher levels of iron and zinc in the kernels. These lines may be used for the introgression of the traits concerning micronutrient enhancement into the popular elite cultivars. When compared to the estimation with AAS, the staining methods with Prussian Blue and Dithizone (DTZ: 1,5-diphenyl thiocarbazone) are found be very cost effective and precise in identifying and categorizing the lines as micronutrient rich/deficit. The varying color intensities serve as a reliable selection criterion for grain micronutrient contents in maize and other cereal crops. These protocols, could, therefore, be effectively used as the initial screening methodology and so the genotypes might be identified for higher grain micronutrient contents among huge population in a short period of time.     

Effect of manures and fertilizers on soil physical properties,build-up of macro and micronutrients and uptake in soil under different cropping systems: a review

Combined application of manures and fertilizers played a pivotal role in the improvement in soil physico-chemical properties, macro and micronutrients distribution and their transformations under different cropping systems. Based on a cropping system, the different levels of manures and fertilizers were used to study improvement in physico-chemical properties of soil. The aim was to explore the appropriate application of organic manures and inorganic fertilizers for improved sustainable yields of a cropping system. Intensive cropping systems lead to N, P, K, Zn, Cu, Fe, and Mn deficiencies in surface and subsurface soil, which could be refreshed with combined application of manures and fertilizers. The application of manures and fertilizers controls the pH and electrical conductivity of soil. Moreover, manures and fertilizers showed improvement is soil physical conditions viz. bulk density, particle density, porosity, and water holding capacity etc. Manuring coupled with fertilization helped to great extent for macro and micronutrient transformations in the soil. Under these transformations, the soil solution and water soluble component (fractions/pools) of soil is enriched with macro and micronutrients. There was a consistent declining trend of DTPA-extractable Zn, Cu, Fe, and Mn in the sub-surface soil in comparison to the surface layer, which may be ascribed to increase in pH with increase in depth and decrease of organic matter with depth. Similarly, manures reduced the concentration of residual macro and micronutrients in soil. Recently, integrated nutrient management system (INMS) is gaining importance vis-a-vis maintaining the soil fertility with conjunctive use of chemical fertilizers plus organic manures.     

Micronutrient deficiencies and toxicities of cassava plants grown in nutrient solutions. I. Critical tissue concentrations

The programmed nutrient addition technique was used in a series of 5 experiments to determine the response in growth and micronutrient content of cassava (Manihot esaulenta Crantz) cv. M Aus 10, to 8 supply levels of boron, copper, iron, manganese and zinc respectively. The experiments were of 9 weeks duration and utilized 22 litre pots of nutrient solution. The supply levels for each micronutrient covered the range from severe deficiency to toxicity. Critical tissue concentrations for deficiencies determined by relating total dry matter production to the nutrient concentration in the youngest fully expanded leaf blades were (μg/g): boron 35, copper 6, manganese 50, and zinc 30. Likewise, critical concentrations for toxicities in the same index tissue were (μg/g): boron 100, copper 15, manganese 250, and zinc 120. In the iron experiment, the data were too variable to allow precise determination of critical concentrations for deficiency and toxicity. Critical micronutrient concentrations in the petioles of the youngest fully expanded leaves were also determined, but offered no advantage over the leaf blades.     

Leaf mineral element concentrations and growth of sweet sorghum subjected to acid soil stress

Abstract

The nutritional profile of sweet sorghum [Sorghum bicolor (L.) Moench] cultivars grown under acid soil field stress conditions is a critical consideration when developing plants which are adapted to these infertile soils. Uptake and accumulation of macro‐ and micronutrients vary among genotypes and ultimately Influence plant growth and development. This study compared fourteen sweet sorghum germplasm lines and varieties for their Individual patterns of leaf nutrient concentrations and productivity when grown under acid soil field conditions (pH 4.45 to pH 4.85) at three locations over a two‐year period. Significant year x location interactions were found for Fe, K, and Ca concentrations at both Blairsville and Calhoun and for Mn and P levels at Blairsville and Calhoun, respectively. Data from Calhoun on plant height, dry weight, visual stress ratings, and rainfall indicate a possible association between drought tolerance and acid soil tolerance in sorghum. No significant differences in A1 concentrations were found among these sweet sorghum lines and varieties, which indicate that their acid soil tolerance mechanisms are probably not related to A1. MN 1054 accumulated the highest levels of Mn in the three acid soils. The highest concentrations of Mg and P were found in Brandes. MN 960 had the highest visual stress ratings (highest susceptibility) while Brandes, Ramada, Roma, and Wray were the most tolerant. All fourteen cultivars apparently have some tolerance to acid soil stress conditions.     

Properties and available micronutrient status of some soils derived from Abeokuta formation in Nigeria

Available iron, zinc, copper and manganese were determined in six pedons located in upper slope, middle slope and valley bottom soils derived from Abeokuta geological materials in Nigeria. The soils had an average of 639.8 g kg^?1 sand, 241.8 g kg^?1 clay and 118.4 g kg^?1 silt. The fertility status of the soils was low–medium with a strongly acid–neutral reaction, 1.3–15.1 g kg^?1 organic carbon contents, moderate–high exchangeable bases and 1.38 mg kg^?1 available phosphorus. Both Fe (122.50 mg kg^?1) and Mn (111.40 mg kg^?1) occurred at toxic levels, whereas the mean Cu (1.27 mg kg^?1) and Zn (2.56 mg kg^?1) contents were found to be adequate for most crops grown in the region. There were significant positive correlations among the micronutrients and also between soil pH, organic carbon, particle size fractions and micronutrients. The high levels of Fe and Mn were probably due to the presence of oolitic ironstone in the parent material.     

The role of root plasma membrane ATPase and rhizosphere acidification in zinc uptake by two different Zn-deficiency-tolerant wheat cultivars in response to zinc and histidine availability

ABSTRACT

We investigated the effect of histidine (His) and Zn deficiency on H⁺-ATPase activity and H⁺ release from wheat roots. Two bread wheat (Triticum aestivum L. cvs. Kavir and Back Cross Roshan) were grown in a nutrient solution for four weeks before being transferred to treatment solutions consisting of two concentrations of His (0 and 50 µM) and two concentrations of Zn (0 and 10 μM). The Zn-only and the Zn+His treatments were observed to release more H⁺ in the root media than did the control ones, with the highest achieved under the Zn+His treatment which was roughly 2.1 times higher than that under the control conditions. The H⁺ release from wheat roots increased slightly but significantly in the presence of only His when compared with the control solutions. The hydrolytic and transport activities of H⁺-ATPase were affected by both Zn deficiency and His supply. In both cultivars, application of Zn and His resulted in a higher hydrolytic activity of H⁺-ATPase when compared with the control solutions. The highest hydrolytic activity of H⁺-ATPase in the root plasma membrane vesicles was achieved with the Zn+His treatment. The ‘Back Cross Roshan’ exhibited a higher (PM) H⁺-ATPase activity and H⁺ pumping than did ‘Kavir’.     

Leak-preventing effect of synthetic soil conditioners in paddy field

Synthetic soil conditioners have been studied by many soil scientists, but their studies were mainly on the formation of the water-stable aggregate of soils. But it may be possible that, if synthetic soil conditioners, the water-soluble polymers, are spread on the plowsole of the leaky paddy field, the leakage of water is prevented by the thin layer of the polymer formed by the swelling with irrigation water.     

Enhancing micronutrient uptake and yield of wheat through bacterial PGPR consortia

A pot experiment was undertaken under net house conditions, with three rhizobacterial strains AW1 (Bacillus sp.), AW5 (Providencia sp.) and AW7 (Brevundimonas sp.), applied along with 2/3 recommended dose of nitrogen (N) and full dose of phosphorus (P) and potassium (K) fertilizers (N₉₀P₆₀K₆₀). An enhancement of 14–34% in plant biometric parameters and 28–60% in micronutrient content was recorded in treatments receiving the combination of AW1?+?AW5 strains, as compared to full dose of fertilizer application. The treatment involving inoculation with AW5?+?AW7 recorded highest values of % P and N, with a two-fold enhancement in phosphorus and 66.7% increase in N content, over full dose application of P and K fertilizers. A significant correlation was recorded between plant biomass, panicle weight, grain weight, N, P and iron (Fe) with acetylene reduction activity, indicating the significance of N fixation in overall crop productivity. Our study illustrates the multiple benefits of plant growth promoting rhizobacteria (PGPR) inoculation in integrated nutrient management and biofortification strategies for wheat crop.