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
PERFORMANCE OF GRAIN YIELD, BIOCHEMICAL AND ANATOMICAL CHARACTERS UNDER WATER STRESS CONDITIONS IN SOME BREAD WHEAT GENOTYPES
A field experiment was carried out during 2013/2014 and 2014/2015 winter growing seasons at the Experimental Farm, Kafr El-Hamam Agricultural Research Station, Zagazig, Sharkia Governorate, Egypt, to evaluate 20 wheat genotypes and cultivars under three irrigation regimes. Plants in the first regime were irrigated four times after planting irrigation (normal irrigation I1). In the second regime plants were irrigated two times after planting irrigation (I2). In the third regime plants were given one surface-irrigation 25 days after planting irrigation (I3). A wide border (7m) was made to minimize the underground water permeability surrounded each experiment. The experiment was laid out in a split-plot design with three replications. Highly significant genotype differences were registered for grain yield and its components in both seasons and combined. The interactions between genotypes and water regime treatments for grain yield and its components were highly significant for all characters in both seasons and combined except for 1000 grain weight in first season. The obtained results showed that I1 treatment gave the highest water consumptive use and applied irrigation water. Results indicated that values of water consumptive use in the first season were 520.1, 382.6 and 275.3 mm for irrigation regimes I1, I2 and I3, respectively. However, in the second season the corresponding values of the water consumptive use were 494.7, 370.9 and 263.4 mm, respectively. Genotype No. 2 gave the least value of water consumptive use, while genotype No. 13 recorded the highest water consumptive use. Water utilization efficiency (kg grains/ m applied water) revealed that I3 gave the highest value, whereas I1was the lowest one. The highest water utilization efficiency was registered by Genotype 8, while genotype 3 recorded the lowest value for this measurement. Drought sensitivity index (DSI) reveal that genotypes No 1, 5, 8, 10, 12, 16 and 18 were tolerant to water stress. Moderate drought stress resulted in significant increase in total soluble sugars, proline and free amino acids in the studied genotypes. Under sever stress, the above mentioned characters significantly increased in genotypes No 1, 2 and 3 compared to other tested genotypes. Therefore wheat genotypes No.1, 2 and 3 could be classified as more tolerant to moderate drought stress. Anatomical features of 5 wheat genotypes were influenced by drought stress. It has been noticed that genotype No. 20 recorded the highest reduction in anatomical characters. On the other hand, the least reduction was detected in genotype No. 1 compared to other tested genotypes. Genotype No. 1 appeared to be more tolerant to drought stress as it exhibited DSI less than unity and gave increase in total soluble sugars, proline and free amino acids with lowest reduction in leaf anatomical characteristics. The study recommend genotype No. 1 as more tolerant to drought stress with good level of yield productivity.
The Study of Relationship between Berm Width and Debris Flow at the Slope
The purpose of this study is to estimate the behavior and the mechanism of debris flow at the end of mountain side when a berm was set on the inclined plane. The numerical model was performed by using the Finite Difference Method(FDM) based on the equation for the mass conservation and momentum conservation. In order to measure the behavior of the debris flow, the debris flow of a straight channel slope and the debris flow of channel slope with 3 types of berms were compared. First, the flow discharge and the sediment volume concentration at the downstream of the channel slope, depending on the various berm width and the different inflow discharges at the upstream of the channel were analyzed. The longer the berm width, the flow discharge at the downstream of the channel was decreased and the high flow fluctuation was reduced by a berm. And it means that a berm can effect for the delay of the debris flow. Through Root Mean Square ratio(RMS) comparison, the flow discharge of the channel slope with a berm was lower than that of a straight channel slope. The longer the berm width, for the sediment volume concentration, an inflection point did not show but mild curve. Because the low sediment concentration with water mixture by a berm continuously flow at the downstream end, it will be effect for reducing the disaster caused by debris flow. The results of this study will provide useful information in predicting and preventing disaster caused by the debris flow.