JOURNAL OF AGRICULTURAL SCIENCE AND SUSTAINABLE PRODUCTION
Year:2002 | Volume:12 | Issue:2|Papers Count:13

Study was conducted during 2000-2001 in sugarbeet fields of Miandoab Plain (Northwest of Iran). Five species from 4 genera belonging to the family Acaridae were collected and identified. From all the mites collected, Cosmoglyphussp. near batsyleviZakhvatkin is a new recording in Iran and Acarus tyrophagoides Zakhvatkin, Tyrophagussimilis Volgins, T. putrescentiae (Schrak) and Rhizoglyphus robini Claparede in Miandoab region. Tyrophagus putrescentiae and Rhizogly phusrobini, were found to be dominant species in the area.

In order to investigate the causes of drain discharge inefficiency and waterlogging in the Fars Meat Complex draiped lands, located in Drood-Zan plain, the, soil transmissivity coefficient (KD) through direct and indirect methods and intake rate of soil by double ring infiltrometer were measured. In direct method, the soil transmissivity coefficient was determined through measuring soil hydraulic conductivity (K) by inverted auger hole method and thickness of the aquifer (D) by soil profile examining. In indirect method, this coefficient was calculated from measuring of drainage discharge (q) and the hydraulic head (h) midway between two parallel drain by using Hooghoudt's formula assuming steady state condition. The results of this study showed that, soil texture from the surface down to 2.3 m depth is clay and the transmissivity coefficient obtained by direct and indirect methods were 1.110 and 0.376 m2/d, respectively. The result of direct method agrees with the results for the other parts of the Drood-Zan plain. The magnitude of this coefficient in indirect method was one third of the direct method. By applying the optimum values for hand q provided by the reports on other parts of this plain, and KD from the indirect method in Hooghoudts equation and assuming steady state condition, the appropriate estimated drainage spacing turned to be 24m. This spacing is one fourth of the currently existing distance in the area under study. Therefore, it seems that the indirect method of KD determination is superior to the direct one, because the amount of soilvolume engaged in the trail is much higher than the direct method. The results of infiltration measurement showed that mean basic infiltration rate is 1.37cm.hr -1. Further examining of soil in the studied area showed that the 25 cm of surface soil have doddy structure and cracks with mean diameter, distance and depth of 1.0,20, and 30 cm respectively. Below this, there is a layer with 35 cm thickness and with clay content of 62% and bulk density of 1.7 g.cm-3. It seems that this layer slows the flow of percolating water down into the lower part of the profile and leads to water logging. Therefore, to manage or eliminate this problem, further study in needed.

The experiment was conducted with 360 white Leghhorn layers during 38-54 weeks of age. Dietary ME levels included 2500, 2600, 2700 & 2800 Kcal/kg, and CP levels were adjusted regarding to CP: ME ratios proposed by NRC (1994) for Leghorn type layers, whereas CP: ME proposed by NRC considered as control, 7.5% lower and 7.5% higher than the control were considered as high protein and low protein levels, respectively. The trial was arranged as a 4x3 factorial completely random design. Each diet was allocated to 5 replications, where each consisted from 2 layout cages, and 3 laying hens in each cage. At the end of the experiment ME and CP levels significantly (P<0.001) effected on the feed intake, egg weight, daily eggmass production, feed conversion ratio, layingrate, dietary cost of 1Kg produced egg, and daily variable profit hen. Liver fat percentage was significantly affected (P<0.05) by CP levels and MExCP interactions. Regarding to feed intake, egg production, and cost of diet, ME levels of 2500 kcal/kg and 2600 kcal/kg were the best levels for reducing the dietary cost of egg production, however the level of 2600 kcal/kg showed the highest variable profit per hen.Control CP level (NRC proposed CP: ME) caused the lowest dietary cost of egg production, and the highest variable profit per hen, thus the level was the best dietary ratio of CP: ME. Diets containing 2600 kcal/kg ME and 13.45% CP, and 2500 kcal/kg and 13.9% CP showed the best economic results, respectively, with variable profits of 74.45 and 73.08 Rls/day. Regarding to broken and soft shelled eggs, body weight change, mortality, albumen quality (Haugh unit), shell thickness, shell% abdominal fat% and liver fat% (occurrence likelihood of FLD), there was not any significant difference between the diets and the best diets. Thus the these two diets can be selected as the best for increasing economic profit However, regarding to safety margin, in practical conditions, farmers culture, and variable profit, the diet containing 2600kcal/kg ME and 13.45% CP, was proposed as the most favorable levels of dietary ME and CP for Leghorn layers, during the second phase of laying period.

Considering the importance of alternative food sources for predators in times of prey scarcity, effect of five species of aphids; Aphis fabae Scop., A. gossypii Glov., Acyrthosiphon pisum (Harr.), Myzus persicae (Sulz.) and Sipha maydis Pass. were studied on mortality and developmental time of three larval instars, puparium, Weight of one day- old puparium, growth rate index, adult longevity, fecundity and egg fertility of Leucopis glyphinvora Tanas. Adverse effects of preys, S.mayd and A.Gossypii were observed on the biology of predator due to their defensive mechanism and characteristics of host plant. Effects of six adult artificial diets including alfalfa pollen + corn pollen+ water, four mixtures of sugar or honey + yeast + water as artificial honeydews, distilled water and honeydew of A. fabae as control treatment were studied. Alfalfa pollen + corn pollen + water and distilled water treatments decreased adult longevity and inhabited oviposition. Artificial honeydews decreased adult longevity and fecundity but were not significantly different. It seems that the presence of a sugar in a diet is necessary for maintenance energy of L.glyphinivora. This predator is probably a proovigenic insect and oogenesis completed with consumption of food supply of larval stages.

A 56 days trail was conducted on 250 commercial broiler chicks to evaluate the using of raw potato powder (RPP) in broiler diets. The experiment was divided into 3 periods of starter (weeks 2 & 3), grower (weeks 4, 5 & 6) & finisher (weeks 7 & 8). Eight day old chicks were divided into 5 treatment groups of control (0%), 10%, 20%, 30%& 40% RPP. The percentages represent the amount of maize replaced with RPP in experimental treatments during starter & grower period. In the case of finisher, all treatments were fed with the control diet. There were five replications for each treatment and each replication contained 10 chicks. At 56Th, day two birds from each replication were sacrificed to evaluate carcass efficiency. Results of using RPP in the diets showed that no significant difference (P>0.05) was observed on weekly feed intake except at weeks 5 & 6. Significant differences (P<0.05) were observed in weekly weight gain & FCR during the experiment except in week 7. Using RPP in broiler diets caused a reduction in weight gain & an increase in FCR. No significant difference (P>0.05) was observed on abdominal fat pad prcentage, but the differences observed on carcass and liver gain were significant (P< 0.05); RPP reduced the carcass gain and increased the liver gain.

Salinity and alkalinity are the principle problems in arid and semi - arid regions. Utilization of water for the reclamation of saline and alkali soils is essential and unavoidable. Water is usually scared in such areas. As a result, any method of land reclamation that could save any drop of water is important from an economic point of view so, a research project using a factorial randomized block design was conducted in Rudasht Salinity Station, Isfahan. Four leaching treatments were accomplished before planting. These treatments were: T2, T4, T6 and T5, with 50, 30, 10 and 0 centimeters of leaching water respectively. The other treatments were two wheat varieties. Irrigation of the plots was accomplished according to the tradition of the region. Between the first and second irrigations, T8 received two additional irrigations (32 cm water). Salinity profiles showed that treatments T2, T4 and T8, could provide appropriate seed beds from the salinity point of view.T6 was significantly different from the other three treatments. T8 treatment seems to be superior to other treatments, for no need of water before planting of seeds, and we save time and costs of reveling of the land.

In order to study the effect of indices on yield and yield components of soybean cultivars in mixed cropping, an experiment was conducted in split block design with randomized complete block orientation in four replication at the College of Agriculture Ferdowsi University of Mashhad. Soybean cultivars (Williams, Century and Hobbit) were mixed planted in three combination of 2 cultivars at four planting ratios (0:4, 1:3, 2:2 and 3:1) with population density of 45 plants/m2 and row spacing of 55cm. The results indicated that plant height and the number of branches were affected by different planting ratios, whereas, the number of pods in the main stem was not affected by using these ratios, but the highest number of pods was observed in the third middle portion of the stem. The highest number of pods per plant and seed per plant were observed in Hobbit and Williams’s combination. The empty pod percentage of Hobbits, in combination with other cultivars, showed significant difference as compared with it in pure stand. The percentage of empty pods in the third upper portion of plants was more than the other parts. The combination of Century and Williams in 2:2 ratio had highest yield and the combination of Century and Hobbit in 3:1 ratio resulted in lowest yield.

In oder to calculate the optimum farm size in rural production cooperatives in Hamadan Province, 645 units of production belonging to rural cooperatives were selected randomly in a two - stage process and relevant information was collected on the basis of questionnaire. Data was statistically analyzed and relationships between variables and correctness of estimated parameters were tested on the basis of mathematical procedures and econometric patterns. In this study relevant computer software’s were used. Theoretical basis for the calculation of optimum farm size is presented and the results are discussed. This study showed that with the addition of every hectare to the farm size, the cost of farming per hectare is reduced by 2580 Rails. Under present conditions the cost of farming per hectare is 522707 Rails. If the optimum farm size of 167.8 hectare is attained, the farming cost per hectare is reduced to 125732 Rails. Meanwhile the optimum farm size for cost minimization is 12.8 hectare in irrigated wheat farming and 74.4 hectares for dry farmed wheat.

In order to determine the best quantitive index for assessment of chickpea response to drought, a field experiment was conducted in 1996 at Experimental Station of Agricultural Research Center of Kurdistan, Iran. In this experiment 24 genotypes of desi type chickpea were sown at two sowing time and two moisture levels including, rain fed and irrigated conditions in a factorial split -plot experiment with three replications. Genotypic differences were observed for 14 recorded traits and five different drought response indices [DRI (Drought Response Index), STI (Stress Tolerance Index), TOL (Tolerance), MP (Mean Productivity) and GMP (Geometric Mean Productivity)].Their values were estimated to identify tolerance of chickpea alines to drought. Correlation coefficients, scatter plots and principal component analysis show that STI and MP are the best indices for drought resistance evaluations in chickpea. Using these indices, four high yielding and early maturing drought tolerant genotpes (ICCV 93032, ICCV 94008, ICCV 90033 and ICC 89204) were selected. A registered drought resistant line, ICC 4958, which produced highest seed yield, but due to its large seed size and dark yellow color, is not a desirable variety in the country. It is therefore, recommended to be used as progenitor in drought tolerance breeding programs.

Carp is a part of forelimb and is placed distal extremity of forearm and proximal extremity of metacarpus which composed of small bones. Relationship between the carpal bones makes its structure very interesting. Forelimb and specially the carp tolerate most of the body weight.Arrangement of carpal bones in relation to each other and adjacent bones of the region is important in diagnosis and treatment of displacement, fractures of the bones and any disorder in carpal articulation. The Samples for this survey were provided from boffalo's forelimb (distal regione of forearm). Radiographic treatment was performed on these samples in anterior - posterior and lateral position. Then samples were entered to liquid calcium carbonate and were boiled at 100°C for 4 to 5 hours. To our knowledge, there is no information about the structure of boffalo's carp. There are six bones arranged in two (position and distal). Four bones are located in proximal row and two in distal row. Proximal bones, from medial to lateral, are arranged as follow: radil carpal, intermediate carpal, ulnar carpal and accessory carpal bones, respectively. The accessory carpal bone is placed palm lateral to the carp and articulates with palmar aspect of the ulnar carpal bone. The shape of the buffalo's accessory carpal bone is pyramuidal and directed caudoproximally in the palmar region, which is different from cattle. This characteristic of buffalo's accessory carpal bone is similar to the horse accessory carpal bone. Distal row bones from medial to lateral are carpal bones 2+3 and 4, respectively. The carpal is probably eliminated and second and third carpal bones are fused during developing. Among the carpal bones, accessory carpal bone is the smallest and radial carpal bone is largest.