Boris Lazarević

Quantification of aluminum-induced changes in wheat root architecture by X-ray microcomputed tomography

ABSTRACT Root architectural traits are of fundamental importance for plant performance, especially under unfavorable soil conditions. This study examined the effect of aluminum (Al) toxicity in different growing media (nutrient solutions and soil) on root architecture of two wheat (Triticum aestivum L.) cultivars with different Al tolerances. Seedlings were grown in acidic and limed soil and in two contrasting nutrient solutions. Root systems of soil-grown plants were scanned using x-ray microcomputed tomography (µCT) while that of nutrient solution–grown plants were assesses using WinRhizo, 3 and 5 days after planting (DAP), respectively. Aluminum caused significant reduction of all examined root traits (number of seminal roots, root length, length of the longest seminal root, root surface area, and root volume). Growth in acidic soil caused significant reduction in root length, length of the longest seminal root, and root surface area at 5 DAP. Soil-grown plants produced a larger root system compared to plants grown in nutrient solutions. Aluminum toxicity–induced differences of root traits were also found between different nutrient solutions. Beside the well-known reduction of root length, Al toxicity had a profound effect on other root architectural traits. X-ray µCT has revealed root architectural changes under specific conditions of acidic, Al-toxic soil. Differences obtained in Al-induced effects on root architecture between different nutrient solutions as well as between different growing systems emphasize the need for further study of root architecture, especially under specific conditions of Al toxicity in acidic soils.

Gas exchange capacity of Croatian common bean landraces (Phaseolus vulgaris L.) is related to their origin and growth type

The long tradition of common bean (Phaseolus vulgaris L.) cultivation in Croatia has resulted in the development of many landraces, which create a valuable basis for screening different physiological traits. Studying gas exchange parameters could provide valuable information that could be useful in creating new crop germplasm with enhanced agronomic attributes. Variability of gas exchange parameters, such as the net photosynthetic rate (A), transpiration rate (E), stomatal conductance (gs), intercellular CO2 concentration (Ci), light use efficiency (LUE), and water use efficiency (WUE) were studied on the collection of 226 common bean accessions and the relationship of the gas exchange parameters with the origin and morphological traits was tested. The highest variability among all landraces was found for the WUE and gs, and lowest for the A and LUE traits, indicating high potential of these traits to be used for selection and breeding programs. Accessions of the Mesoamerican origin had higher A and LUE and lower Ci values compared to accessions of the Andean origin. Accessions with the determinate growth had higher gs and Ci values and lower A, LUE and WUE values compared to accessions with the indeterminate growth. The variance components analysis showed that the growth type has a more pronounced effect on gs, Ci and WUE, whereas the origin has a stronger impact on A and LUE. The principal component analysis (PCA) showed that A separates accessions according to their origin, whereas Ci separates accessions according to their growth type. Accessions with higher Ci had lower A, indicating possibly higher rates of carboxylation per active site on Assist. Prof., PhD, Boris Lazarević, Department of Plant Nutrition, Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, HR-10000 Zagreb, Croatia, tel: +385 1 2393961, e-mail: blazarevic@agr.hr * This work has been fully supported by the Croatian Science Foundation under the project UIP-11-2013-3290.

Protein content in common bean row seeds in relation to a* and b* dimensions of the L*a*b* color space

Abstract Background: In Egypt, liver diseases are one of the most prominent killers especially hepatitis virus infection, fibrosis and cirrhosis . Hepatitis has a serious health effects and alter the functions of the

Status of Fe, Mn and Zn in red beet due to fertilization and environment

Soil is a non-renewable resource, so it should be taken care of it. High quality food with sufficient yield for a growing human population can be produced only if plant nutrients are added to the soil by fertilizers to increase soil fertility, but the fertilizers have to be used economically, with the aim of raising the nutrient content available in the soil in order to meet plants’ needs. The goal of the present investigation was to determine the effect of application of organic and mineral fertilizers as well as the effect of research environment on micronutrient content in red beet root. A field trial (2003–2005) was set up in a hilly part of Croatia according to the Latin square method, with four types of fertilization (control, 50 t stable manure*ha-1, 500 and 1,000 kg NPK 5-20-30*ha-1). After digestion of plant material with concentrated HNO3, iron, manganese, and zinc were determined by an atomic absorption spectrophotometer (AAS). The highest average red beet root micronutrient contents (270 mg Fe*kg-1 in dry matter, 96 mg Zn*kg-1 in dry matter, and 53 mg Mn*kg-1 in dry matter) were determined in the first research environment (Brasljevica in 2003) with low potassium soil content. There was a general decreasing trend in contents of the studied micronutrients (Fe, Mn and Zn) with NPK 5-20-30 fertilization (and by application of high doses of potassium), certainly due to antagonistic activity with potassium. It is suggested to fertilize with both 500 kg NPK 5-20-30*ha-1 and microelement fertilizers.

Genetic Diversity of Croatian Common Bean Landraces

In Croatia, the majority of the common bean production is based on local landraces, grown by small-scale farmers in low input production systems. Landraces are adapted to the specific growing conditions and agro-environments and show a great morphological diversity. These local landraces are in danger of genetic erosion caused by complex socio-economic changes in rural communities. The low profitability of farms and their small size, the advanced age of farmers and the replacement of traditional landraces with modern bean cultivars and/or other more profitable crops have been identified as the major factors affecting genetic erosion. Three hundred accessions belonging to most widely used landraces were evaluated by phaseolin genotyping and microsatellite marker analysis. A total of 183 different multi-locus genotypes in the panel of 300 accessions were revealed using 26 microsatellite markers. Out of 183 accessions, 27.32% were of Mesoamerican origin, 68.31% of Andean, while 4.37% of accessions represented putative hybrids between gene pools. Accessions of Andean origin were further classified into phaseolin type II (“H” or “C”) and III (“T”), the latter being more frequent. A model-based cluster analysis based on microsatellite markers revealed the presence of three clusters in congruence with the results of phaseolin type analysis.