THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

Soil Nutrient Bioavailability—A Mechanistic Approach

The essentiality of B for growth and development of plants is well-known, but the primary functions of B still remain unknown. Evidence in the literature supports the idea that the major functions of B in growth and development of plants are based on its ability to form complexes with the compounds having cis-diol configurations. In this regard, the formation of B complexes with the constituents of cell walls and plasma membranes as well as with the phenolic compounds seems to be a decisive step affecting the physiological functions of B. Boron seems to be of crucial importance for the maintenance of structural integrity of plasma membranes. This function of B is mainly related to stabilisation of cell membranes by B association with membrane constituents. Possibly, B may also protect plasma membranes against peroxidative damage by toxic O2 species. In B-deficient plants, plasma membranes are highly leaky and lose their functional integrity. Under B-deficient conditions, substantial changes in ion fluxes and proton pumping activity of the plasma membranes were noted. Impairments in phenol metabolism and increases in levels of phenolics and polyphenoloxidase activity are typical indications of B deficiency, particularly in B deficiency-sensitive plant species, such as Helianthus annuus (sunflower). Enhanced oxidation of phenols is responsible for generation of reactive quinones which subsequently produce extremely toxic O2 species, thus resulting in the increased risk of a peroxidative damage to vital cell components such as membrane lipids and proteins. In B-deficient tissues, enhancement in levels of toxic O2 species may also occur as a result of impairments in photosynthesis and antioxidative defence systems. Recent evidence shows that the levels of ascorbic acid, non-protein SH-compounds (mainly glutathione) and glutathione reductase, the major defence systems of cells against toxic O2 species, are reduced in response to B deficiency. There is also increasing evidence that, in the heterocyst cells of cyanobacteria, B is involved in protection of nitrogenase activity against O2 damage.

Boron deficiency-induced impairments of cellular functions in plants: a review

Heavy metals are transferred from the abiotic environment to living organisms, accumulated in biota at different trophic levels, and thus contaminate the food chains/webs. Trophic transfer, bioaccu...

Trophic transfer, bioaccumulation, and biomagnification of non-essential hazardous heavy metals and metalloids in food chains/webs—Concepts and implications for wildlife and human health

Plant Analysis: An Interpretation Manual

Boron (B) is considered as an essential element for plant growth and development. Sexual reproduction in plant is more sensitive to low B, than vegetative growth. Considerable research activities have been directed at accentuating the physiological and biochemical role of B in plant growth and development. This paper reviews the literature (upto the year 2006) focusing on the role of boron in cell wall integrity, cell division, plasma membranes, phenol metabolism, and its requirement for the nitrogen fixation and in the reproductive growth of plants. KEYWORDS: Boron; plant growth; cell division; cell wall; Pakistan. INTRODUCTION Mineral nutrition of plants is important for controlling physiological and biochemical processes of plants. Its deficiency may lead to changes in these processes and disturbed plant growth and yield. Boron is one of mineral nutrients that are required for normal plant growth. The essentiality of B for growth and development of higher plants has been earlier demonstrated (27, 43, 46). The main functions of boron relate to cell wall strength and development, cell division, fruit and seed development, sugar transport and hormone development. Some functions of boron interrelate with those of nitrogen, phosphorus, potassium and calcium in plant. The most important functions of boron in plants are thought to be its structural role in cell wall development; and stimulation or inhibition of specific metabolism pathways.

Role of boron in plant growth: A review

Waqar Ahmad1, Munir H. Zia2, Sukhdev S. Malhi3, Abid Niaz4 and Saifullah5,6 1Faculty of Agriculture, Food, and Natural Resources, The University of Sydney, 2Research & Development Section, Fauji Fertilizer Company Ltd, Rawalpindi, 3Agriculture and Agri-Food Canada, Melfort, Saskatchewan, 4Soil Chemistry Section, Institute of Soil Chemistry & Environmental Sciences, Ayub Agricultural Research Institute, Faisalabad, 5Institute of Soil and Environmental Sciences, University of Agriculture Faisalabad, 6School of Earth and Environment, Faculty of Natural and Agricultural Sciences, The University of Western Australia, Crawley, Perth, 1,6Australia 2,4,5Pakistan 3Canada

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Boron Deficiency in Soils and Crops: A Review

In the developing world, vegetables are commonly grown in suburban areas irrigated with untreated wastewater containing potentially harmful elements (PHEs). In Pakistan, there is no published work on the bioaccessibility aspect of PHEs and dietary minerals (DMs) in sewage-irrigated soil or the vegetables grown on such soils in Pakistan. Several industrial districts of Pakistan were selected for assessment of the risk associated with the ingestion of vegetables grown over sewage-irrigated soils. Both the total and bioaccessible fraction of PHEs (Cd, Co, Cr, Ni, and Pb) and DMs (Fe, Cu, Mn, Zn, Ca, Mg, and I) in soils and vegetable samples were measured. The concentrations of these PHEs and DMs in sewage-irrigated and control soils were below published upper threshold limits. However, compared to control soils, sewage irrigation over the years decreased soil pH (7.7 vs 8.1) and enhanced dissolved organic carbon (1.8 vs 0.8 %), which could enhance the phyto-availability of PHEs and DMs to crops. Of the PHEs and DMs, the highest transfer factor (soil to plant) was noted for Cd and Ca, respectively. Concentrations of PHEs in most of the sewage-irrigated vegetables were below the published upper threshold limits, except for Cd in the fruiting portion of eggplant and bell pepper (0.06–0.08 mg/kg Cd, dry weight) at three locations in Gujarat and Kasur districts. The bioaccessible fraction of PHEs can reduce the context of dietary intake measurements compared to total concentrations, but differences between both measurements were not significant for Cd. Since the soils of the sampled districts are not overly contaminated compared to control sites, vegetables grown over sewage-irrigated soils would provide an opportunity to harvest mineral-rich vegetables potentially providing consumers 62, 60, 12, 104, and 63 % higher dietary intake of Cu, Mn, Zn, Ca, and Mg, respectively. Based on Fe and vanadium correlations in vegetables, it is inferred that a significant proportion of total dietary Fe intake could be contributed by soil particles adhered to the consumable portion of vegetables. Faecal sterol ratios were used to identify and distinguish the source of faecal contamination in soils from Gujranwala, Gujarat, and Lahore districts, confirming the presence of human-derived sewage biomarkers at different stages of environmental alteration. A strong correlation of some metals with soil organic matter concentration was observed, but none with sewage biomarkers.

Health risk assessment of potentially harmful elements and dietary minerals from vegetables irrigated with untreated wastewater, Pakistan

Boron (B) is an essential microelement, which is necessary for reproductive organs including pollen tube formation in wheat (Triticum aestivum L), and flowering and boll formation in cotton (Gossypium hirsutum L) The study was associated with wheat-cotton rotation in 80 farm fields, belonging to different soil series, in four districts of cotton belt of Punjab, Pakistan to assess concentrations of extractable B in soils [005 M hydrochloric acid (HCl) extractable B], and added fertilizer B and their relationship to some soil physico-chemical properties [pH, organic matter (OM), calcium carbonate (CaCO3) and clay content], yields and total B concentrations in wheat and cotton plants All soils had alkaline pH (745 to 855), high CaCO3 content (214 to 865%), less than 10% OM (033 to 099%), low plant available-P (Olsen P less than 8 mg kg−1 soil) and medium ammonium acetate extractable potassium (K) (< 200 mg K kg−1 soil) Of the 80 soil samples, 65 samples (81%) were low in available B (<045 mg B k

Relationship of soil extractable and fertilizer boron to some soil properties, crop yields, and total boron in cotton and wheat plants on selected soils of punjab, pakistan

Seven extractants widely used to determine plant-available boron (B) from either acidic or alkaline soils were tested for 20 alkaline and calcareous soil series from cotton belt of Punjab, Pakistan. The hot-water-soluble boron (HWS-B) extraction procedure was used as a benchmark to see any relative variation in available B in comparison with alternate extractants [0.05 M hydrochloric acid (HCl), 0.018 M calcium chloride (CaCl2), 1 M ammonium acetate (NH4OAc), 0.25 M sorbitol–diethylenetriaminepentaacetic acid (DTPA), 0.05 M mannitol prepared in 0.01 M CaCl2, 0.005 M ammonium bicarbonate (AB)–DTPA]. The soil series used in this study belonged to four soil orders (Aridisols, Entisols, Alfisols, and Inceptisols). The greatest mean B concentration (0.32 ± 0.11 mg kg−1) was obtained by hot water extraction followed by 0.05 M HCl extraction (0.31 ± 0.12 mg kg−1), whereas the lowest was obtained by 0.25 M sorbitol–DTPA (0.24 ± 0.06 mg kg−1) extraction. The comparison between soil series showed that the greatest ...

Abid Niaz

Papers

Role of boron in plant growth: A review

Boron Deficiency in Soils and Crops: A Review

Health risk assessment of potentially harmful elements and dietary minerals from vegetables irrigated with untreated wastewater, Pakistan

Relationship of soil extractable and fertilizer boron to some soil properties, crop yields, and total boron in cotton and wheat plants on selected soils of punjab, pakistan

Relative Efficiency of Different Extractants for Available Boron Estimation in Alkaline Calcareous Soils