April-June 2020


Effect of Arginine on Growth Characters of Two Maize Hybrids under Water Deficit conditions

Amal G. Ahmed, Nabila M. Zaki and Hassanein M.S.

ABSTRACT: Two field experiments were carried out at private farm Wadi El-Rayyan, El-Fayoum governorate, Egypt, during the two successive summer seasons of 2017 and 2018 to study the effect of skipping one irrigation with or without arginine on growth characters of two maize hybrids (Fine Seeds- 101 and T.W. 329). Normal irrigation gave the highest value in all growth characters under study followed by omitting the 5th irrigation + 200cm3/ fed., arginine. Fine Seeds- 101 cultivar significantly surpassed T.W. 329 cultivar in plant height (cm), total dry weight / plant (g), number of ear /plant, leaf area (dm2), leaf area index, leaf area ratio, specific leaf area and specific leaf weight in both seasons. The interaction between maize cultivars and water shortage with or without arginine were significant in all growth characters in both seasons except leaf area (dm2) and leaf area index. The best treatment for plant height (cm), total dry weight / plant (g), number of ear /plant, leaf area ratio, specific leaf area and specific leaf weight was normal irrigation + Fine seeds- 101. Also, the best treatment was omitting 5th irrigation + 200 cm3 / fed., arginine with Fine Seeds- 101 cultivar for plant height (cm), total dry weight / plant (g) and leaf area ratio.

[ FULL TEXT PDF 168-172 ] DOI: 10.36632/csi/2020.9.2.16


Selenium Behavior in the Soil, Water, Plants and its Implication for Human health. A review

El-Sayed A.A., M.A Abou Seeda, A.A Yassen, A. Khater and Sahar M. Zaghloul

ABSTRACT Selenium (Se) is proved an essential trace element in the nutrition of humans, animals, and some bacteria, however, it is considered as a beneficial element that have the potential to influence the antioxidant activity systems of the higher plants, showing beneficial to toxic characteristics in a narrow concentration range. Nonetheless, its essentiality for plants is still controversial. Some regions of the world present high Se levels in soils causing several functional disorders and diseases in plants and people who live in seleniferous regions. Selenium is playing among other functions a relevant role in the antioxidant system of mammals, but lead to toxicity when taken in excessive amounts. Adsorption capacity of Se on soils is affected by soil characteristics such as pH, mineralogy and texture, organic matter content and Se chemical form, redox condition, and interactions with other ions. Behavior of Se in plants was chemically similar to sulfur, hence taken up inside the plants via sulfur transporters present inside root plasma membrane, metabolized via sulfur assimilatory pathway, and volatilized into atmosphere. Inadequate Se levels in the soil and human body is a well-known concern in many parts of the world. This malnutrition problem is often due to Se-poor diet; probably because of the low Se availability in soils where plants are growing, which are consider the main source of dietary Se. However, paradoxically some regions of the world present high Se levels in soils causing several functional disorders and diseases in people who live in seleniferous areas. Therefore, selenium should be supplied in controlled amounts to avoid harmful effects, taking into account the importance of the soils as a way to ensure the adequate Se supply for the population. This review has dealt with Se behavior in soil environment and plants, its presence in water and its relevance for plant growth and the human health.

[ FULL TEXT PDF 173-197 ] DOI: 10.36632/csi/2020.9.2.17


Importance of sulfur and its roles in Plants physiology: A Review

Abou Seeda M.A., Abou El-Nour E.A.A., Yassen A.A., Gad Mervat M. and Sahar M. Zaghloul

ABSTRACT Sulfur is one of the most versatile elements in life. It functions in fundamental processes such as electron transport, structure, and regulation. In plants, additional roles have developed with respect to photosynthetic oxygen production. Sulfate uptake, reductive assimilation, and integration into cysteine and methionine are the central processes that direct oxidized and reduced forms of organically bound sulfur into its various functions. Sulfite reductase (SIR) is a key enzyme in higher plants in the assimilatory sulfate reduction pathway. The reduction of SIR activity caused chlorotic and necrotic phenotypes in tobacco leaves, but with varying phenotype strength even among clones and increasing from young to old leaves. The levels of downstream metabolites were reduced, such as cysteine, glutathione (GSH) and methionine. This metabolic signature resembles a sulfate deprivation phenotype as corroborated by the fact that O-acetylserine (OAS) accumulated. In addition, chlorophyll contents, photosynthetic electron transport, and the contents of carbohydrates such as starch, sucrose, fructose, and glucose were reduced. Amino acid compositions were altered in a complex manner due to the reduction of contents of cysteine, and to some extent methionine. Interestingly, sulfide levels remained constant indicating that sulfide homeostasis is crucial for plant performance and survival

[ FULL TEXT PDF 198-231 ] DOI: 10.36632/csi/2020.9.2.18