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اسلام مجیدی
هروان
author
مریم
شهبازی
author
text
article
1994
per
The salt tolerance of 2 bread wheat cultivars were evaluated in pot and petri dishes grown under different salt solutions. The results indicated that the cultivar shoeleh was more tolerant than Bay at. The dilutions of Persian golf sea water at 40 and 60% , saline soil extract at 20 and 40% could be used to distinguish the differences between cultivars. Among characters studied, the number and length of roots and plant height were significantly different for the treatment at 1% level of probability.
Iranian Journal of Agriculture Science
پرديس کشاورزي و منابع طبيعي دانشگاه تهران
1
v.
0
no.
1994
https://jijas.ut.ac.ir/article_15913_96af775970564eaa6bb6f1a7cd7f5a78.pdf
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بهمن یزدی
صمدی
author
حجت اله مظاهری
لقب
author
text
article
1994
per
To study the resistance of alfalfa to alfalfa weevil, 124 Iranian and introduced alfalfa varieties and lines were studied in three field and one greenhouse - experiment (s). Traits studied were amount of damage to the plants, rate of insects on the plants, plantheight,flowering time, dry yield and cytological situation of the varieties. The results showed that some resistant varieties have the resistance mechanisms of tolerance, however, some other may have mechanisms such as antibiosis or non—preference, or a combination of both.
Iranian Journal of Agriculture Science
پرديس کشاورزي و منابع طبيعي دانشگاه تهران
1
v.
0
no.
1994
https://jijas.ut.ac.ir/article_15914_e5d907920dc81d36662b53d9c95c6ce3.pdf
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سیاوش
روحانی
author
text
article
1994
per
A study the profitability of sugar beet crop production and inorder to understand the obstacles and problems encountered in the expansion of the acreage of this crop, costs and benefits of sugar beet farming were investigated in Hamedan province. In the present study, in addition to collecting relevant information from the specialists and informed sources, data on costs and benefits was obtained from sugar beet farmers in a specilly designed questioner.
The area under study was divided into four categories on the basis of acreage. Mechanized and non-mechanized farms were studied separately. Mean comparisons of cost, yield, and profit showed significant differences at0.005% level except in two cases. The analysis of data showed that 80 percent of the production costs was spent on irrigation, Cultivation, thinning, and transportation.
Irrigation costs were 46.77 percent and 39.04 percent of the total costs in mechanized and non-mechanized farming, respectively. Transportation cost was 18-19 percent. of the total costs in both production methods. Thinning and cultivation made up 11.21 and 78 percent of the total costs in mechanized and non-mechanized farming, respectively.
There was a positive relationship between the amount of labor required and the cost in all farming operation, Labor required farminq 1 hectar of sugar beets with mechanized and non-mechanized methods was 418.7 and 702.4 hours respectively, As a result of saving 283.7 hours of labor per unit area, mechanized farming cost less than non—mechanized farming. The study showed that due to the prevalence of traditional crop maintenance practices in sugar beet production, increasing the acreage causes an increase production socts and a reduction in productivity.
In mechanized farming, the average yield and production cost per hectar in 1—hectar and 5—15 hectar farm were 30.50 tons 437660 Rials and 25.01 tons 505730 Rials, respectively, while in non-mechanized farming,. the average yield and production cast per hectar in 1—hectar and 5-15 hectar farms were 28.40 tons—48830 Rials and 2303 tons 560570 Rials, respectively. Among the seven regions, Assadabad with 36.6 tons had the highest yield per hectar. In this region, the farms who used mechanized farming method and the lowest production cost of 387200 Rials per hectar.
Iranian Journal of Agriculture Science
پرديس کشاورزي و منابع طبيعي دانشگاه تهران
1
v.
0
no.
1994
https://jijas.ut.ac.ir/article_15915_e921dea5838b69baab79381f8f7ac6e7.pdf
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محمداخوان
قالیباف
author
احمد
جلالیان
author
بهروز مصطفی
زاده
author
سید فرهاد
موسوی
author
text
article
1994
per
In arid regions, due to limited chemical weathering, resalinization with salt redistribution in the soil is important. In the Rudasht alluvial plain of Isfahan, the pattern of salt reaccumulation in the soils were investigated by studying topography, ground water fluctuation, and water application and distrubution. Data collected from water levels during one year shows in regions of lower topography salts accumulate on the surface, if excess water is not drained. It is recommended to use low salt water for irrigation and pump the excess water to control ground water level and to reduce soil salinity. Earth canals (Muddies) are also contributing to soil salinization. Zayandehrud river terraces sometimes create lower regions and nonuniform natural drainage and hence are partly responsible for soil salinization. In the study area, because of macro—relief, the local hydraulic gradient is opposed to the general hydraulic gradient, thus, preventing drainage of salt water from the region. The critical depth of ground water to prevent salt accumulation is proposed to be 2.5 m. In summary, factors contributing to salt accumulation and redistribu- tion are: heavy soil texture, relief, earth canals, and the system of water application and distribution.
Iranian Journal of Agriculture Science
پرديس کشاورزي و منابع طبيعي دانشگاه تهران
1
v.
0
no.
1994
https://jijas.ut.ac.ir/article_15916_ff0abb670f549174636b825535a42e6b.pdf
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علی
احمدی
author
بهمن یزدی
صمدی
author
text
article
1994
per
Iranian Journal of Agriculture Science
پرديس کشاورزي و منابع طبيعي دانشگاه تهران
1
v.
0
no.
1994
https://jijas.ut.ac.ir/article_15917_f4d37bcc0ca7579b3ca9920bb70943b9.pdf
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کاظم
پوستینی
author
د.آ.
بیکر
author
text
article
1994
per
The responses of CO2 uptake, transpiration and stornatal conductance from two wheat cultivars, Known to be tolerant (Sholeh) and intolerant (Inia-66), grown in saline conditions (0, 2.5 and 5 g/l NaCl) were measured using Infra Red Gas Analyser, in a split plot design . The results showed that with Sholeh the CO2 uptake was reduced only at the highest level of salinity used. Parallel reductions to CO2 uptake in transpiration and stomatal conductance in both cultivars indicate that in saline conditions the stomatal resistance to CO2 may greatly cause reductions in Photosynthesis. Microscopic observations on leaf tissues showed that CO2 flux may partly be limited by alterations in leaf internal structure.
Iranian Journal of Agriculture Science
پرديس کشاورزي و منابع طبيعي دانشگاه تهران
1
v.
0
no.
1994
https://jijas.ut.ac.ir/article_15918_563eaf377729357864bd23761d303bb4.pdf