Leaf Anatomical Characteristics in Relation to Grain Yield of Wheat ( Triticum aestivum L.) Cultivars
An experiment was carried out to study the variability of leaf anatomical characters of wheat ( Triticum aestivum L.) cultivars and their association with grain yields. Results indicated that in most of the cases cultivar differences were significant. In respect of 6th leaf anatomical characters, simple correlation coefficients indicated that most of the leaf anatomical traits had significant negative relation with grain yield whereas in respect of flag leaf anatomical traits, only the association between radial dimension of big xylem vessel and grain yield was significantly negative and the correlation between number of veins and grain yield was significantly positive. Key words: Leaf anatomy, wheat, yield, correlation Â  doi: 10.3329/jbs.v15i0.2156 Â  J. bio-sci. 15: 153-158, 2007
Morphophysiological and Photosynthetic Reactions of Wheat (T. aestivum L.) and Its Wild Congeners to Drought Condition In Vivo and In Vitro
The results of the complex analysis of different wheat species tolerance to drought stress in vivo at different levels of organization as well as in vitro on callus cultures, which was conducted, are presented. The objects of research are as follows: species of wheat— T. monococum L. (A u ), T. dicoccum Shuebl. (A u B), T. polonicum L . (A u B), T. aethiopicum Jakubz. (A u B), T. macha Dek.et.Men. (A u BD), T. compactum Host. (A u BD), and T. aestivum L. (A u BD). The methods of this research are physiological, biotechnological, and cytological. The focus was on nonspecific reactions of cereals to osmotic stress, and species-specific changes according to growth and anatomical and photosynthetic parameters which depend on studied species ploidy were shown. It was shown that results of testing of plant tissues in vivo and in vitro are comparable. It demonstrated the criterions for selection of drought-tolerant forms. Optimal selection criteria were identified, and more drought-resistant wheat species were identified.
APPARENT PHOTOSYNTHESIS AND LEAF CHARACTERS IN RELATION TO LEAF POSITION AND AGE, AMONG CONTRASTING LOLIUM GENOTYPES
Summary 
The effect of leaf position, specific leaf weight and chlorophyll on light-saturated apparent photosynthesis, and their relationships with leaf mesophyll, among contrasting Lolium genotypes are described. Within a range of up to four fully expanded leaves on a tiller, the lower (older) leaves had greater photosynthetic activity than the upper (younger). For any particular leaf, maximum photosynthesis was attained prior to full expansion. These effects were closely related to differences in mesophyll cell size. A wide range in leaf chlorophyll levels exhibited by Lolium mutants was not associated with differences in apparent photosynthesis. Specific leaf weight and chlorophyll content were greater in thin leaves with small mesophyll cells than in thick leaves with large cells. Chlorophyll content was not associated with differences in photosynthesis in limiting light (500 ft-candles).