Previous models which describe the water‐content potential relationship for plant tissue do not account for die presence of apoplastic water in the tissue and its variation with water potential. This could cause errors in determination of tissue water parameters which are sensitive to plant water deficits. The theory was modified to account for apoplastic water fraction and used to determine the osmotic potential at full and zero turgor and tissue elastic modulus from moisture release curves for leaves of three winter wheat (Triticum aestivum L.) cultivars grown under moderately high and low stress environments in eastern Washington. Moisture release curves for individual leaves were obtained using a pressure chamber. Apoplastic water content was obtained independently from moisture release curves of frozen leaves using a hydraulic press. Osmotic potential at full and zero turgor showed significant responses to environment with leaves from the drier location having osmotic potentials 5 bars or more lower than leaves from the more moist site. Shifts in osmotic potential from wet to dry portions of the season were also about 5 bars. Apoplastic water fraction and elastic modulus were relatively insensitive to environment, averaging around 0.3 and 200 bars, respectively. Significant cultivar differences were found in tissue osmotic potential, but these did not correlate with performance of the cultivars in droughty environments. The study showed that apoplastic water in tissue, if not corrected for, markedly influences osmotic potential measurements using expressed cell sap since this water, which is essentially solute‐free, dilutes the cell sap when the membranes are destroyed. The tissue water parameters studied provide further insight on physiological factors important in plant resistance to moisture stress.

This work conducted on the research farm of Mallawi Agricultural Research Station, El-Minia Province, Egypt, during two successive seasons of 2004 and 2005 to study the role of the late plantings on the productivity of soybean. Three out of four genotypes selected to achieve that goal were new released cultivars, Giza-22; Giza-35; and Giza-111, and the commercial one, Crawford, the common parent of the three genotypes, as control. Three planting dates started on June 1 st , June 15 th for the second date of sowing and ended on June 30 th for the third sowing date in both seasons. The package of the recommendations of soybean culture carefully applied to get the best results of each sowing date. The results showed that all of the morphological, yield and productivity traits highly significantly affected by genotype and three out of five morphological traits, number of days to both flowering and maturity and plant height, also highly significantly affected by late sowing date. The other two traits, number of branches and leaf area at 75 days just significantly affected by late sowing date. In terms of yield and its components traits, only seed index highly significantly affected by late sowing date and yield per plot significantly affected by sowing time. All productivity traits were significantly affected by late sowing date specially the content of both oil and protein. Although yield per plot was significantly affected by late sowing date, the yield per plant was not affected by late sowing date indicating that the factor of time of sowing may affect the rate of the germination and control the stand of the plots. Number of active nodules considered as productivity trait because of the residual nitrogen that remain in the soil after harvest for the next crop. This number was significantly affected by sowing time and reached the highest values in the second date of June 15 th that may due to the high temperature at this time which lead to increasing the interaction between soybean roots and the nodule bacteria.

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Stevia rebaudiana, is an economically important medicinal plant act as sweetener substitute for diabetic and obese people. Climate modification causes a considerable influence on the production of several secondary metabolites of plants. In the present investigation, the effect of environmental factors on genetic divergence for three varieties of Stevia rebaudiana (Spanti; China and Eg1) by using differential response for different climate modification (black net, white net and plastic cover in comparing to without cover treatment (control) was studied. Data indicated that the application of different modification treatments showed that the use of nets had significant effect on air and substrate temperature and light intensity as well as relative humidity. In the same context, vegetative growth traits and biochemical analyses for stevioside and rebaudioside content had significant effects according to climate modification treatments. Electrophoresis banding patterns of total protein and isozyme (peroxidase) were obtained to characterize genetic relationship for both different treatments and genotypes. Based on the resolved soluble protein profiles it could be detected 11 and 13 polymorphic unique bands for different treatments and genotypes, respectively. The percentage of polymorphism for all studied treatment and varieties was 100 %. 12 and 13 polymorphic bands were detected in Isozyme marker (peroxidase) analysis for different treatments and genotypes, respectively. However, black net treatment and Spanti variety has the highest polymorphism percentage 100% by using cluster analysis of banding pattern for examined treatments and genotypes based on similarity index and UPGMA resulted four distinct clusters.

Two field experiments were conducted at the Agricultural Research Station of gemmeiza, ARC, El-Gharbia Governorate during 2011/2012 and 2012/2013 seasons in order to evaluate the performance of thirteen Faba bean genotypes for seed yield per plant and its related characters. Four statistical procedures, i.e. correlation and multiple regression analysis, factor and cluster analysis were applied to determine the main contributing characters in seed weight per plant variation. Genotype 2 possessed the earliest flowering plants and Genotype 9 (mutant 1) possessed the earliest matured plants. Genotype 8 followed by Genotype, 6, 4 and 1 showed the tallest plants, highest number of pods, seeds, seeds yield per plant and 100 seed weight. Highly significant and positive associations were obtained between seed weight/plant and each of number of seeds/plant and number of pods/plant. The full model regression gave R-square of 0.995, which means that 99.5% of the variation in Faba bean yield is explained by the independent variables in the model. Step-wise regression analysis for seed yield / plant as dependent variable and the other traits as independent, revealed that number of seeds, 100seed weight and number of branches are the most important seed yield / plant components. These traits accounted for 99.26% of total variation exist in seed yield / plant. Factorial analysis classified the eight studied characters, as yield per plant components, into three main factors explained 79.49% of the total variability in the dependent structure. Factor 1 was responsible for 35.71% of the total variation and included number of pods/plant, number of seeds/plant and seeds yield /plant. Factor 2 included100seed weight, days to maturity and plant height contributed by 24.49% of the total variation. Number of branches/plant and days to flowering accounted for 19.29% of the total variation. Graphically, showing eigen values in response to number of components for the estimated variables of Faba bean. The hierarchical cluster analysis permitted the classification of the genotypes according to similarity groups. Analysis of variance for traits studied showed significant differences among the genotypes. Phenotypic coefficient of variation for most characters was closer to the corresponding genotypic coefficient of variation values, showing little environmental effect on the expression of these characters. The highest values of phenotypic and genotypic coefficients of variation were obtained with number of branches/plant, seeds yield/ plant, number of seed and number of pods/plant indicating a wide range of variation which provided a good opportunity for yield improvement. Also, large proportions of heritability coupled with high values of genetic advance (% of mean) were recorded for the number of branches/plant, seeds yield/ plant, number of seeds and the number of pods/plant, explaining that these traits have more chance for Faba bean yield development among the tested genotypes.