Showing 6 results for Assad
Hooman Razi, Mohammad Taghi Assad,
Volume 2, Issue 1 (spring 1998)
Abstract
Two field experiments were conducted in 1996 at the experimental station, College of Agriculture, Shiraz University at Badjgah. Fourteen cultivars consisting of eight hybrids and six open pollinated cultivars were grown in two randomized complete block designs with four replications.
The well-watered experiment received water when evaporation reached 65±5 mm from class A evaporation pan.
The water-limited experiment was irrigated in terms of 125±5mm evaporation from class A evaporation pan. Days to flowering, days to physiological maturity, head diameter, stem diameter, number of leaves per plant, plant height, number of filled seeds per head, 1000 seed weight, kernel percentage, unfilled seed percentage, seed yield, oil percentage, oil yield and harvest index were measured.
Most of the traits including seed yield and oil yield showed considerable genotypic and phenotypic variations. Highly significant differences were observed among cultivars. In normal and water stress conditions, the highest seed yield were obtained by Louc and Armavirsky cultivars, respectively. Water stress significantly decreased yield and its components. Furthermore, days to physiological maturity reduced in response to water deficit. However, oil percentage did not differ significantly. Drought resistance indexes were calculated in order to evaluate the response of each cultivar to water deficit. No association was found between yield potential and the stress susceptibility index, suggesting that drought resistance and high yield potential may be combined to improve sunflower cultivars. In addition, it was revealed that selection for height mean productivity and stress tolerance index will improve yield and drought tolerance simultaneously. Among cultivars that were used in this study, Armavirsky, besides having a relatively higher yield, was also drought tolerant.
J. Pourreza, H. Nasrollahi, A.h. Samie, M. Mohammadalipour, A. Assadian,
Volume 3, Issue 4 (winter 2000)
Abstract
In order to study the effects of Total Dissolved Solids (TDS) in water on the performance of broiler chickens, preliminary data were obtained on water resources of Isfahan Province. Complementary tests and analyses were also performed including physical, chemical and microbial ones. Six different water qualities based on TDS contents of less than 1000, 1000-2000, 2000-3000, 3000-4000, 4000-5000 and more than 5000 ppm were selected. The main experiment lasted for 7 weeks (7-56 days), using 288 chickens in a completely randomized design, with 3 replications, while, the environmental and genetic factors were controlled in an identical broiler housing.
The results showed that using water with different TDS contents had the most negative effects on mortality rate (%) in the rearing period and up to 56.2% mortality was recorded at the highest TDS content. Water consumption showed high and positive correlation (P < 0.05) with TDS (r = +0.74). Correlation between TDS and bedding moisture was also high (r = +0.65) and significant (P < 0.05). The differences between final body weight of control chickens and highest level of TDS were significant (P < 0.05). Feed intake also was affected by different TDS contents and showed similar results as with body weight. Increasing the TDS level decreased the abdominal fat in the female chickens and ash content of tibia in the male chickens. It is concluded that water TDS should be considered for the development of broiler chicken farms. Therefore, it is recommended that higher quality waters (with a TDS content of 3000 ppm) must be used for this purpose. Otherwise, appropriate systems should be used to improve physical and chemical composition of the water.
A. Hemmat, A. Assadi Khoshoei,
Volume 6, Issue 2 (summer 2002)
Abstract
To increase mechanized cotton planting in areas with saline irrigation water and crust forming soil in Isfahan Province, assessment of seeders in flatland planting method with or without crust breaking is essential. An experiment was conducted at the Kabootarabad Research Station of Isfahan Research Center to compare the performance parameters of planting equipment in a clay loam soil. Four planting equipment treatments using Bazrsazan and John Deere planters and Nordsten drill along with three crust breaking methods, including rolling cultivator, rolling-type crust breaker and no crust breaking, were laid out in a factorial experiment within a randomized complete block design with three replications. Planters’ performance was evaluated by measuring the number of plants and plant spacings in each treatment, and estimation of the mean and standard deviation, multiples index, miss index, quality of feed index, precision, and hill-dropping index.
Although the plant spacings, and not the seed spacings, were measured in this experiment, the indices used in this research showed the planters’ performance to be very satisfactory. The suggested hill-dropping index showed the multiple seeds dropping characteristics of the seeders to be better than those of the multiples index regardless of the crust breaking methods. In the non-crust breaking method, the multiple seeds dropping tendency of Bazrsazan planter brought about a reduction in the mean and standard deviation of plant spacings. Crost breaking caused a reduction in plant spacings for all seeders, especially for the drill whose multiple seeds dropping tendency was negligible. The results indicated that the seed metering systems in Bazrsazan and John Deere planters were volumetric rather than single seed metering devices.
J. Yasrebi, N. Karimian, M. Maftoun, A. Abtahi, A. Ronaghi, M. T. Assad,
Volume 7, Issue 4 (winter 2004)
Abstract
Twenty-five surface samples of calcareous soils of Fars Province were used to study the distribution of different nitrogen (N) forms to determine the relationship between the N forms and soil charcteristics, and to obtain regression equations for prediction of N forms from soil characteristics. The forms determined were: soil total nitrogen NO3-N by phenol disulfunic acid NO3-N extractable by 2 M KCl NH4-N extractable by 2 M KCl, 1 N sulfuric acid, and 0.25 N sodium hydroxide oxidative released N by acid permanganate and alkaline permanganate and NH4-N extractable by 2 M KCl at 100 oC. The highest amount of N was that released by alkaline permanganate which constituted 4.47% of soil total N and the lowest form was exchangeable NH4+ which amounted to only 0.6% of total N. Water soluble and exchangeable forms accounted for less than 2% of total N. Highly significant correlations were found between total N and acid permanganate-N (r=0.931) and total N and alkaline permanganate-N (r=0.850). Highly significant regression equations were obtained for prediction of soil total N, acid permanganate-N, and alkaline permanganate-N from soil organic matter (OM), which is an indication of a close relationship of these N forms with OM.
M. Modarresi, M. T. Assad, M. Kheradnam,
Volume 7, Issue 4 (winter 2004)
Abstract
Yield is a quantitative trait and improving grain yield through direct selection is time-consuming. Indirect selection consisting of selection indices is more promising. A field experiment was conducted during 1999-2000 growing season in two experimental locations (Kooshkak and Badjgah) of College of Agriculture, Shiraz University, Shiraz. Thirteen corn hybrids were used in a randomized complete block design with three replications in each location. Thirty-five traits were measured in five developmental stages (stem elongation, tasseling, blister, hard dough and physiological maturity) and combined analysis of variance and covariance were conducted. Finally, 12 traits were selected for constructing selection indices via path analysis. Two optimum selection indices were used in this experiment. In both selection indices, different combinations of traits applied as linear function (multivariate linear model) and coefficients of traits in combinations were calculated. The coefficient of indices were obtained from: b=P-1Ga, where b is the vector of index coefficients, P-1 is the inverse of phenotypical variance and covariance matrix, G is the matrix of genotypical variance and covariance and a is the column vector of traits heritability. In the first index, heritability of traits with the same sign was used as economic values. Selection index including grain yield and net assimilation rate in the second stage (NAR2) was the best. In the second index, the sign of genotypic correlation with yield was given to economic values. Finally, selection index including grain yield and NAR2 was the best, too. In both selection indices, correlation of selection indices with genotypic value was equal to 1. This was 14% higher than the first index including yield alone. In both selection indices, physiological indices including net assimilation, crop growth, and relative growth rates were the most important traits comprising the best selection indices.
N. Alizadeh, A. Babai-Ahary, Y. Assadi, M. Valizadeh, B. Passebaneslam,
Volume 10, Issue 3 (fall 2006)
Abstract
Rape seed (Brassica napus L.) containing more than 40 per cent oil is one of the best oilseeds for cultivation in Iran. Sclerotinia stem rot is one of the important diseases of the rape seed, the causal agent being Sclerotinia sclerotiorum. The aim of our study was to assess the effect of the disease on the quantity and quality of the extracted oil and remaining foodstuff in a field experiment. In this research three cultivars including Okapi, SLM046 and Talayeh were examined under field conditions using a factorial design (cultivars and inoculations were two factors under study). The cultivars were inoculated with SK4 isolate of S. sclerotiorum. The inoculation was done on the plant stems at 30 cm height above the soil using Lewartosca method during mid flowering stage. One thousand- seed weight and glucosinolate, erucic and oleic fatty acids contents of the seeds were determind after the harvest. The results indicated that the infected plants in comparision with the controls had a lower 1000- seed weight and oleic acid content and a higher glucosinolates and erucic acid contents. There were significant differences among the genotypes in respect to all the studied traits except 1000- seed weight. Inverse correlation was observed between 1000- seed weight and erucic acid content or oil glucosinolates contents. It was concluded that the disease can reduce quantity and quality of seed oil and other nutrient contents.
