Year:2002 | Volume:7 | Issue:4|Papers Count:8

This study was carried out with the objective of evaluating the response of genotypes of hexaploid wheat to salinity stress during germination and as well as field Performance. In the first experiment, a factorial design treatment on the basis of completely randomized design with three replications was designed. There were two factors in the experiment; wheat genotypes in eight levels and the EC of water at four levels i.e. 0,5,10 and 15 ds/m. Petri dishes containing seeds after adding salt solution, were placed in a seed germinator at 20˚C±2. Daily reading of Mean Germinating Time (MGT) and Final Germination (FG) were recorded. At the end of germination, the mean Hypocotyls length (SL), the Root Length (RL) of the highest root and mean root number in each seed (RNO) were noted. The second experiment was carried out in the field plots with three replication. The same eight genotypes of wheat were grown and irrigated with irrigation water having EC of 0.76,5 and 10 ds/m in such a way that all the genotypes received all the irrigation treatments. The analysis of variance indicated that during germination period, there was a signigicant differences between the wheat genotypes and the EC of irrigation water decreased germination significantly. In the second experiment, there was an interaction between the genotypes and the EC of the irrigation water and all the characters measured with exception of RNO were signigicantly decreased as a result of increasing salinity. However the ratio of shoot weight to root weight was increased. The ANOVA also indicated that the interaction between the year and genotypes was significant for the grain yield. Increasing the salinity of irrigation water decreased the grain yield, however not the number of grains per plant spike.

The relative resistance of 30 rice genotypes of Gilan province to the Striped Stem Borer (SSB) was compared under the field conditions. Also the relationship between plant silica content of nine genotypes with their susceptibility to the SSB was investigated. It was found that the genotypes under investigation varied in their resistance to the pest. None of the genotypes were completely resistant, but genotypes 443, Neda, 445, Nemat, Anbar-bo and Binam Proved to be relatively resistant. A weak negative correlation (r=0.14) was observed between the silica content of the rice stem and its susceptiblity to the SSB, which may confer some resistance to the pest. Therefore, it is recommended that in an IPM system of the Chilo suppressalis, genotypes with relative resistance such as Nemat, Anbar-bo and Binam and also genotypes with high levels of silica in their- stems, such as Nemat, Khazar and Sepid roud to he used.

We must pay attention that in our country severe soil erosion and high percentage from pastures had increased to threefold of their capacity, so providing of forage and protein as a need is very important. This study was carried out as a split -plot and complet random blocks (CRB), at Varamin (Pakdasht), Abureyhan high educational complex farm in 1376. It studied three cultivars of forage Sorghum and the best planting date to get high forage yield. Different planting dates were 3.2.76, 18.2.76, 3.3.76 and 18/3/76 culivars were selected among new ones as: Speedfeed, Sugar graze and Jumbeo. In this study tests were placed in main plots and varieties in minor plots, so It took care the varieties. Forge yield accounted for wet and dry weight, the other cahracters were measured as: leaf numbers, shoot diameter, shoot height, rate of leaf / shoot pod weight (ə), leaf surface index and rate of dry / wet weight (ə). Results showed that wet forage in all three varieties at first and second dates 3/2/76, 18/2/76 were put in one group After drying the amount of dry forage for Sugar graze cultivar and planting date 3/2/76 with 34.13 t/ha had showed the highest rate. Leaf number of Sugar graze on 18/2/76 with 22.5 leaves were the most. Shoot diameter and plant height as two clear indexes for Sugar graze cultivar at second planting data with 4.4 cm and 325 cm mean were better than the others. Leaf surface index for Sugar graze at second planting date and for Speedfeed and Jumbo at first planting date 3/2/76 were put in one group. These measured characters and results showed that rate of leaf / shoot pod weight and rate of dry/wet weight for Sugar graze cultivar were less than the others. The best treatment (D2.V2) was belonged to Sugar graze variety at second planting date 18/2/76 which was prefered to the otheres in Varamin.

For determination of lead content in soil and paddy crops of the agricultural area of adjacent highway, with due attention to the natural altitudes, two stations at area near the mountain, and two stations at an open area (field) were selected. The paddy crops and soil samples from each stations were collected at the distance of 10, 20, 30, 50, 100 and 150 m from the main road and analysed by AAS M.The results of the statistical analysis (Lsd test) stated that, in most of the agricultural farms, there is a significant variations (with %95 assurity level) between the lead content of soil and agricultural products of 10,20 and 30 m, with those samples of 100 and 150 m distance from the Main road. On other words, The lead content of soil and paddy crops at lesser distance (<30m) from the main road, are much more than those of at higher distance and by increasing the distance from the main road, the concentration of lead in different samples are decreases.

One of the most important practice in forest is the Transportation of the forest products from cutting place till depo (deck, yard) for reloading. It may be done by agricultural tractor, wheel Skidder, Track Skidder, and Cable System or aerial logging , one of the most important costs in forest pnlctice.Due to the in this research, the factors may specially be noticed is the selection of harvesting machinery.Factors would be discussed are: slope, Aspect, ground roughness, soil texture, drainage and ground strength. The study in such work has three different part of the works which are (field work, laboratory work and office work) those of the works are done in a seri of 953 hectars in lavige forest. the combination of those information and also preparing the plan and saving information and graphs are used by softwares of geographical information system (GIS) (IIwis, Arcinfo) and foxpro and also excel software.In this discussion, the combination factors such slope, Aspect and soil texture, ground strength will be determined. As a results of combinning ground strength. Ground roughness and slope, the harvesting units will be created. at last, due to such base suitable machine would be determined. The Factor of ground strength is not the only cause but is dued to other factors.Now we found factors such slope and ground strength can be the factors of limiting to use the harvesting machines in nature.In very optimal condition at the place of study the best equipment of skidding are wheel skidder and track skidder.

The importance of pectin in food is its ability to form the gels that are the basis of jam and other fruit preserves. Although apple pomace and citrus peels are traditional sources for commercial pectin, but sunflower heads could be used also as a source of pectin. Sunflower heads remaining after seed removal and stalks are sources of low-methoxyl pectin. Conditions including pH, temperature and concentrations of pectin, calcium and sugar can be varied during gel preparation to obtain gels with a range of firmness and elasticity. Low-methoxyl sunflower pectin can be used to prepare jellies with low sugar content or without sugar in the presence of a small amount of calcium and could be used as an ingredient formulating of low-calorie foods. In this study sunflower samples (Helianthus annuus L., Var. Armavirsky, Zaria and Record) were obtained from IRAN. Samples were dried and ground by hammer mill to pass 60-mesh size screen and stored until used. Extraction yield of pectin was 10.67,11.53 and 10.93% of the head residues, respectively Qualitavely the Record variety was selected ,based on its the highest methoxyl, lowest ash and galacturonic acid content.

The predatory hug, Orius alhidipennis (Reuter) is one of the most important predator on thrips and other arthropods, but this species prefers especially tobacco thrips, Thrips tabaci Lind. Which is a serious pest on many crops such as onion in field and greenhouse crops in Iran.In this research, limited populations of this predatory bug collected from onion fields in Isfahan province, and then transferred to the insectarium for large scale production under laboratory conditions (25±2˚C, 65±5% RH and a 16:8 L/D photoperiod). We used plexiglass boxes for its production in Lab. and Mediterranian flour moth eggs along with corn pollens as food for dit1'erent stages of nymphal development. Bean pods were used as oviposition suhstrate for female hugs. The oviposition substrates were removed at two or three days intervals and then transferred to glass tubes for eclosion of eggs and nymphal growth. All growth stages of the predator were reared for several generations.The average losses (from egg to adult) were 30% during the production. With considering that cach hug consumed about 35.5 eggs of Mediterranian flour moth, it can be concluded that almost 9541hugs may be produced by one gram of Mediterranian flour moth eggs. In mass production, proper shelfing of Lab. or insectarium can reduce the space requirement for insect rearing.