Showing 32 results for Khajeh
Reza Jamshidian, Mohammad Reza Khajehpour,
Volume 2, Issue 3 (fall 1998)
Abstract
Methods of seedbed preparation affect establishment, growth and yield of crops via manipulating physical and chemical properties of soil. These effects on wheat-mungbean double-cropping have not been studied in Isfahan. Therefore, the influences of various seedbed preparation methods on soil physical properties and nutrients content and on establishment of mungbean (experimental line 1-61-16) were studied in a wheat-mungbean double-cropping system during 1996 at the Agricultural Research Station, Isfahan University of Technology. Two residue management treatments (burned and unburned) along with four tillage systems (moldboard plow, disk, khishchee and no-till) were laid out in a strip plot design within a randomized complete block design with four replications. Bulk density and penetrability of soil at various depths were not affected by residue management at emergence. However, at the time of flowering, bulk density at 0-15 cm soil depth was lower and soil penetrability at 3-15 cm depth was higher in unburned treatment due to mineralization. Rate and coefficient of emergence of seeds were lower in unburned residue treatment. Soil bulk density at 0-30 cm depths was lower and penetrability at 3-21 cm depth was higher with moldboard plowing at both emergence and flowering time. In addition, lower soil N, P and K content at 0-15 cm depth at emergence and flowering time was obtained with moldboard plowing. Rate and coefficient of emergence were strongly lower in no-till treatment. Based on these results and considering sustainable agricultural goals, incorporating residue with disk tillage might be advantageous under conditions similar to this experiment.
Hassan Nassiri Moghaddam, Sayed Hamid Reza Razian, Fariborz Khajeh Ali,
Volume 3, Issue 1 (spring 1999)
Abstract
Effect of different sources of fat on performance of broiler chicks was studied. Three hundred and thirty six chicks were divided into 42 groups of 8 chicks per group. Seven isoenergetic and isonitrogenous diets, mainly based on corn and soybean meal were prepared and fed. These treatments were as follows: corn + soybean meal + (5% tallow, 5% cotton seed crude oil, 5% cotton seed soapstock, 2.5% tallow + 2.5% crude oil, 2.5% tallow + 2.5% soapstock, or 2.5% crude oil + 2.5% soapstock). One control diet without any source of fat was also included. Results showed that average feed intake of diets with different sources of fat up to 56 days old, was not differed from control group. Different sources of fat and their combinations increased weight gain and improved feed conversion. But soapstock had no effect on performance. Added fats increased abdominal fat of chickens. Therefore, if is concluded that on the contrary to soapstock, tallow and crude oil enhanced performance of broiler chickens.
Reza Jamshidian, Mohammad Reza Khajehpour,
Volume 3, Issue 1 (spring 1999)
Abstract
Limited time for crop residue decomposition and complete seedbed preparation in double-cropping necessitates reduced tillage which is associated with its shortcomings. Information about seedbed preparation aspects in double-cropping of wheat and mungbean in Isfahan is lacking. For this reason, the effects of various seedbed preparation methods on growth, seed yield and yield components of mungbean (experimental line 1-61-16) were studied in a wheat-mungbean double-cropping system during 1996 at the Agricultural Research Station, Isfahan University of Technology. Two residue management treatments (burned and nonburned) along with four tillage systems: moldboard plow, disk, khischee and no-till were laid out in a strip plot design within a randomized complete block design with four replications. Improved establishment and plant growth conditions associated with burning residue treatment significantly increased plant density, above ground plant weight, number of nodes per branch, plant height, number of pods per main stem and per square meter, number of seeds per pod on main stem and on branches, number of seeds per main stem, seed yield, biological yield and harvest index. Higher plant density in this treatment resulted in significant reduction in the number of branches and number of pods per branch. Desirable conditions for establishment and growth in disk and moldboard plow treatments significantly increased plant density, above ground plant weight, number of pods per main stem and per square meter, number of seeds per pod on main stem and on branches, number of seeds per main stem, seed yield, biological yield and harvest index. No-till treatment produced the least results in respect to the above traits. The results indicated that burning residues with disk tillage system might be an appropriate seedbed preparation method under conditions similar to this experiment.
B. Bahraini-Nejad, M.r. Khajehpour,
Volume 3, Issue 3 (fall 1999)
Abstract
Combining herbicides for controlling broadleaf weeds and grasses in wheat farms has not been studied under Isfahan environmental conditions. Thus, this experiment was conducted in 1995-96 at the Agricultural Research Station, Isfahan University of Technology, in order to investigate the issue. In this study, 2,4-D+MCPA (U46 Combi Fluid 6), bromoxynil, metribuzin, diclofop-methyl and tralkoxydim and their combinations in 11 treatments plus weed-free and weedy checks were evaluated using a randomized complete block design with 4 replications. Goldbachia laevigata and Avena fatua were the dominant weeds. Cirsium arvense and Convolvulus arvensis were of less importance. Efficacy of bromoxynil on annual broadleaf weeds was higher than 2,4-D+MCPA, while 2,4-D+MCPA was more effective on perennial broadleaf weeds. Diclofop-methyl and combination of bromoxynil with tralkoxydim were the most effective on A. fatua, while differences between treatments containing diclofop-methyl or tralkoxydim on decreasing A. fatua numbers were non-significant. The most and the least visual damages to wheat plants were caused by metribuzin and bromoxynil, respectively. Wheat yield was not significantly affected by treatments. However, the highest yield was obtained by tralkoxydim + bromoxynil treatment, which produced the lowest total dry weight of weeds at terminal spikelet and heading stages of wheat. The results obtained here indicate that combination of bromoxynil with tralkoxydim might be the best treatment for the control of all annual weeds under conditions similar to this experiment. But if perennial broadleaf weeds and wild oat are dominant in the field, combination of 2,4-D+MCPAwith diclofop-methyl might be preferred.
M.r. Khajehpour, F. Seyedi,
Volume 4, Issue 2 (summer 2000)
Abstract
Obtaining high seed and oil yields of sunflower requires coincidence of vegetative and reproductive stages of growth of the plant with suitable environmental conditions via selecting appropriate planting date. Since the suitable date of planting for sunflower cultivars under Isfahan environmental conditions was not determined, this experiment was conducted in 1996 at the Agricultural Research Station, Isfahan University of Technology. In this study, five dates of planting (April 27, May 12 and 27 and June 12 and 29) and three open pollinated sunflower cultivars (Record, Vnimik 8931 and Armavirec) were evaluated using a randomized complete block design with split-plot layout in three replications. Date of planting was considered as the main plot and cultivars were randomized in the sub-plots.
Number of seeds per head (SH), l000-seed weight (SW), seed oil percent (SOP) and, consequently, yields of oil (OY) and seed (SY) were significantly reduced as planting was delayed. Reduction in these traits were considered to be related to the coincidence of vegetative and reproductive growth stages with higher temperatures prevailing at later plantings. Vnimik 8931 had higher SH and SW, and thus produced higher SY. This cultivar had lower SOP than Record, but produced higher OY than Record due to its higher SY. Armavirec was ranked the least for the measured traits, except for its SH that was slightly higher than that of Record. SH was the most contributing trait to the increase in SY, and SY was the most determining trait for the increase in OY. Date of planting by cultivar interactions for SH, SY and OY were significant. Nevertheless, the highest amount of the measured traits were obtained with Vnimik 8931 at the first planting date.
A. Soltani, A.m. Rezai, M.r. Khajeh Pour,
Volume 5, Issue 1 (spring 2001)
Abstract
Identification of easily measured physiological traits contributing to yield under specified environmental conditions would benefit genotypic selection for grain sorghum. A field experiment was conducted to determine broad-sense heritability and expected genetic advance, and to examine the relationships of grain yield with 11 physiological traits related to developmental periods, vegetative growth, growth rate, grain filling rate, and partitioning to the grain.
Sorghum genotypes exhibited significant differences for all traits, except for grain yield. Broad-sense heritability estimates ranged from a low of 49.6 (for grain filling rate per unit area) to a high of 99.4 (for days to maturity). Expected genetic advance ranged between 9.2% (for days to transition of vegetative to reproductive phase, days to maturity and number of leaves) and 39.8% (for grain filling rate per grain unit). Generally, grain yield gave a significant negative correlation with physiological traits related to development and vegetative growth. But, this correlation was positive and significant for growth rate, grain filling rate, and harvest index. Grain yield was low in its coefficient of genetic variation and expected genetic advance. It is, therefore, concluded that indirect selection for grain yield via growth rate, grain filling rate per unit area and harvest index is efficient. Results suggest that use of easily measured physiological traits in sorghum breeding is possible.
M.r. Khajehpour, F. Seyedi,
Volume 5, Issue 2 (summer 2001)
Abstract
Sensitivity of developmental stages of three sunflower cultivars to day length and temperature changes under field conditions were evaluated, and their development rates during various growth stages were modeled in a field experiment conducted in 1996 at the Agricultural Research Station, Isfahan University of Technology. Five dates of planting (April 27, May 12 and 27, and June 12 and 29) and three open pollinated sunflower cultivars (Record, Vnimik 8931 and Armavirec) were evaluated using a randomized complete block design with split-plot layout in three replications. Date of planting was considered to be the main plot and cultivars were randomized in sub-plots.
Number of days from planting (P) to head visible (HV) and P to first anther (FA) were significantly reduced with delay in planting as the result of increase in temperature during these periods. Number of days from P to physiological maturity (PM) was also significantly reduced with delay in P. This response, however, could not be explained by changes in temperature variables or day length. Number of days from HV to FA, in harmony with the partial stability of maximum and minimum temperatures during this period, was not affected by date of planting. Duration from FA to PM of the last planting date was significantly shorter than the other planting dates. This response was related to the persistence of the effect of high and stable maximum temperatures prevailing during HV to FA period of the last planting date. Armavirec was significantly earlier than Record and Vnimic 8931 for number of days from P to HV and from P to FA Cultivars showed significantly large differences for the FA to PM and P to PM durations. Armavirec was the earliest and Record was the latest cultivar. Based on the results obtained, it may be concluded that the cultivars under study were non-sensitive to photoperiod. Development rate (DR) of Armavirec responded linearly and DR of Record and Vnimic 8931 responded non-linearly to increases in temperature variables during P to HV and P to FA Development of Vnimic 8931 was faster than Record at high temperatures. DR of the cultivars decreased linearly during P to PM as day length increased. The relationship between DR and photoperiod could be used as a practical model for estimating P to PM duration of these sunflower cultivars.
M. R. Khajehpour, A. R. Bagherian Naeni,
Volume 5, Issue 4 (winter 2002)
Abstract
It is believed that various types of field bean, including pinto, white and red, differ in adaptability to high temperatures and may, thus, differ in response to delay in planting. In order to evaluate this response, an experiment was conducted during 1996 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with split-plot layout. Main plots consisted of four planting dates (April 28, May 13 and 28 and June 13) and sub-plots included four genotypes of common bean (red bean, c.v. Naz pinto beans, experimental lines 11816 and 16157 and a white bean, experimental line 11805).
Number of branches per plant, number of pods per branch and per unit area, number of seeds per pod of main stem and branch, number of seeds per main stem, per branch and per unit area, 100-seed weight and seed yield significantly reduced, while harvest index significantly increased by delay in planting and consequent increases in temperature and reduction in time for growth. The lower harvest index obtained with early planting was the result of the lower efficiency of the produced vegetative growth due to the coincidence of seed filling period with high temperatures. Pinto bean line 11816 ranked the highest for number of branches per plant and harvest index among the genotypes evaluated and produced the highest seed yield (3030 kg ha-1). Although red bean Naz ranked the highest for number of pods and seed per main stem and per unit area, it had the lowest harvest index and 100-seed weight and, consequently, produced the least seed yield (2254 kg ha-1). The results obtained indicate that delay in planting adversely affects bean seed yield. Pinto bean line 11816 may have higher yield potential among the genotypes studied at all planting dates under conditions similar to the present experiment. No specific relationship was observed between apparent seed characteristics and plant tolerance to heat.
F. Khajehali, H. Nassiri Moghaddam, R. R. Marquardt, M. Danesh Mesgaran,
Volume 6, Issue 3 (fall 2002)
Abstract
Evaluation of uric acid contents of poultry excreta was examined for use in the estimation of apparent protein digestibility. Uric acid was determined either by high-performance liquid chromatography or by spectrophotometric method. A high-pressure liquid chromatographic assay was used with absorbance measured at 285 nm. The method used a reverse-phase system with a C18-bonded column (250*4.6 mm, i.d.). The mobile phase was distilled deionized water. Injection volume was 20 l with a flow rate of 1 ml/min.
Correlation (r) between the two methods for uric acid content of excreta from birds fed diets with different methionine levels was 0.976. The uric acid values were then used to determine apparent protein digestibility. The apparent protein digestibility values, when corrected for uric acid nitrogen, were comparable with those calculated from amino acid analysis.
A. Azari, M.r. Khajehpour,
Volume 7, Issue 1 (spring 2003)
Abstract
Planting pattern through changing vegetative growth and utilization of environmental resourses affects yield components and seed yield. These effects were studied in the spring of 2000 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with a split plot layout and three replications. Main plots consisted of three row distances (30 cm flat, and 45 and 60 cm on bed), and sub-plots included three planting densities (30, 40, and 50 plants m-2). The experiment was planted on March 13 using local safflower variety of Isfahan, named Koseh. Increase in row distance and plant density enhanced most developmental stages of safflower. Leaf area index was not significantly affected by row distance but increased as planting density increased. Up to the 50% flowering stage, 30 cm row distance produced highest plant dry weight, but had the least dry weight at the end of the growing season, probably due to the strong shedding of leaves. Up to the end of flowering stage, 50 plants m-2 treatment produced the highest plant dry weight, but ranked lower as compared to 30 plants m-2 treatment at the physiological maturity, probably due to the shedding of leaves. Row distance had no significant effect on number of branches per plant and per square meter, number of heads per branch, number of seeds per head, 1000-seed weight and harvest index. But number of heads per plant and per square meter as well as seed yield per plant and per square meter significantly decreased as planting distance increased. Plant density had no significant effect on number of branches per plant, number of heads per square meter, number of seeds per head, 1000-seed weight and seed yield. Increase in planting density increased number of branches per square meter, but reduced number of heads per branch and per plant, seed yield per plant and harvest index. The highest seed yield (4769 kg ha-1) was obtained with 30 cm row distance and 40 plants m-2 treatment. On average, 397 kg ha-1 petal was harvested, which has a large economic value. However, petal clipping, over all treatments, reduced seed yield by about 7.4%. Considering the advantages of uniform distribution of plants and adaptation of safflower to flat planting, 30 cm row distance with 40 plants m-2 might be appropriate for planting safflower under conditions similar to this experiment.
N. Dadashi, M. R. Khajehpour,
Volume 7, Issue 4 (winter 2004)
Abstract
A field experiment was conducted in 2000 at the Agricultural Research Station, Isfahan University of Technology, to model the response of four safflower genotypes to day length and temperature changes under field conditions. Five planting dates (March 12, April 12, May 10, June 8, and July 12) and four safflower genotypes (Arak 2811, local variety Koseh, Nebraska 10 and Varamin 295) were evaluated using a randomized complete block design with split-plot layout in three replications. Date of planting was considered as the main plot and cultivars were randomized in the sub-plots. Number of days from planting (P) to emergence (E), stem elongation (SE) to head visible (HV), and HV to flowering initiation (FI) significantly reduced with delay in planting as the result of increase in temperature during these periods. Number of days from P to SE, duration of flowering (DF) and termination of flowering (TF) to physiological maturity (PM) were significantly affected by planting date and reduced as day length increased. The same was observed in the case of number of days from P to 50% flowering (MF) and to PM. Large co-variation of day length with temperature may explain a portion of day length contribution to the variation in the above periods. Varamin 295 was later than other genotypes with respect to the duration from P to HV, and specially, for rosette duration. In addition and for unknown reasons, the rate of development (RD) of Varamin 295 at all developmental periods could not be explained by day length and/or temperature variables. Among other genotypes, Koseh with 125 days, and Nebrska 10 with 118 days from P to PM were the latest and the earliest genotypes, respectively. The response of Koseh to planting dates, as measured by the duration of various developmental stages, differed from Arak 2811 and Nebraska 10. This was attributed to the probable response of Koseh to day length. RD of Koseh, Arak 2811, and Nebraska 10 during P to MF was explained by a linear regression and RD of Koseh during P to PM by a polynomial regression with day length by mean temperature as an independent variable. RD of Arak 2811 and Nebraska 10 during P to PM was explained by minimum temperature. It seems that partial sensitivity of Koseh to day length has a considerable significance in its adaptation to environmental conditions prevailing in the summer under Isfahan climatic conditions.
A. Enferad, K. Poustini, N. Majnoon Hosseini, A. A. Khajeh-Ahmad-Attari,
Volume 7, Issue 4 (winter 2004)
Abstract
In a pot experiment, the growth (Dry matter) responses of 18 rapeseed varieties to three levels of NaCl salinity induced by 1.2, 6, and 12 dS.m-1 were investigated using a factorial experiment with a randomized complete block design in 3 replications. The results indicated that salinity reduced total dry matter, Na concentration, K/Na ratio, ion selectivity of K versus Na, and leaf water potential while it increased K concentration. However, the leaf water potential of the plants had the highest and a significantly negative correlation with total dry matter accumulation. Therefore, it seemed that leaf water content of the plants could explain the tolerance or sensitivity responses to salinity. The rapeseed varieties were accordingly ranked into different groups. The varieties viz, Alice, Fonax, DP.94.8 and Licord were classified as saline tolerant group, and varieties such as Okapi, Akamar and Eurol as saline sensitive group. The remaining eight rapeseed varieties were moderately tolerant. Moreover, the response of rapeseed varieties viz. Consul, VDH8003-98 and Orient were different such that the above explanation could not be applied to them. Therefore, halophytic strategies for these three varieties might be worth further investigation.
N. Dadashi, M. R. Khajehpour,
Volume 8, Issue 3 (fall 2004)
Abstract
Although safflower is known to be a cool-season crop, it is usually planted as a summer crop in Isfahan. Thus, an experiment was conducted in 2000 at the Agricultural Research Station, Isfahan University of Technology, to study the effects of date of planting on growth, yield components, and seed yield of safflower. Five planting dates (March 12, April 12, May 10, June 8, and July 12) and four safflower genotypes (Arak 2811, local variety Koseh, Nebraska 10, and Veramin 295) were evaluated using a randomized complete block design with split-plot layout in three replications. Date of planting was considered as the main plot and cultivars were randomized in sub-plots. Delay in planting from March 12 to may 10 reduced plant dry weight per unit area, number of heads per plant, number of seeds per head, seed yield per unit area, harvest index and petal yield. The above traits increased as planting was further delayed from May 10 to June 8. Highest seed oil and lowest seed protein contents were also obtained for this planting date. Plants of July 12 planting date did not reach physiological maturity. Among the genotypes evaluated and over planting dates, the highest and lowest number of heads per plant, 1000-seed weight, and seed yield were produced byArak 2811 and Veramin 295 (mean of the first and second planting dates), respectively. Highest seed yield (4512 kg ha
-1) was produced by local variety Koseh in June 8 planting date. It might be concluded that this variety has adapted to the summer planting conditions of Isfahan by natural selection.
M . Latifian, H. Seyedoleslami, J. Khajehali,
Volume 8, Issue 3 (fall 2004)
Abstract
Populations of Arboridia kermanshah Dlabola is increasing in Isfahan vineyards. In this study, some morphological characteristics of the immature stages, over wintering sites, number of generations per year, and seasonal population fluctuations of this pest were studied in vineyards in Isfahan Province. Eggs showed apparently four distinct embryonic developmental stages. At 25.8 ±2˚C, development of eggs was completed in 10.9 ± 0.7 days. There were five nymphal developmental stages. Nymphal stages can be distinguished with wing pad development and width of head capsule and width of pronotum. The grape leafhopper overwintered as adults under leaves and crop residues. Rearing studies showed that the grape leafhopper had three generations per year, each lasting 33.9±0.6 (without overwintering period), 46.3±0.7 and 37.3±0.6 days, respectively. Seasonal monitoring of adults, nymphs and eggs showed three or four overlapping periods of activity in the field. Four periods of activities of adults were recorded through season from early May – mid June, mid June – mid July, mid July - late August and early September – mid October.
M. Latifian, H. Seyedoleslami, J. Khajehali,
Volume 9, Issue 2 (summer 2005)
Abstract
Some bioecological aspects of grape leafhopper, Arboridia kermanshah Dlabola, including: the egg distribution under the leaf surface, eggs and nymphs spatial distribution on the vine arms, the adult distribution on three strata of the vine canopy, the adult diel activities and the geographical distribution of this species in Isfahan province were studied. Samplings were done in the 1997. The egg distribution under the leaf surface was determined by repeated sampling during the season and the egg density was estimated on three regions such as the main and secondary vein, the leaf surface margins and others. Eggs and nymphs spatial distribution along the vine arms were studied weekly for six weeks by sampling an arm of five vines during the second generation, the leafhopper population was the highest. The adult spatial distribution on the vine canopy was determined by sampling three strata of the vine canopy using the D-vac apparatus. Diel activities were studied by sweeping nets fifty times per vineyard at the two hour intervals from 8 a.m. to 20 p.m. Temperature and the relative humidity were also measured in the shade once per hour. The presence and the abundance of this species in 87 vineyards in the different climatic conditions were studied by a sweeping net. The leaf margin and around of the secondary vein were preferred for the oviposition of the leafhopper. Adults, nymphs and eggs were more abundant in the middle strata of the vine canopy than others. The mean pattern of the daily activity of the adult indicated one peak at 8 a.m. and the other one at 20 p.m. Maximum temperature thereshold for the adult activities was 28º C. The study of the grape leafhopper distribution in isfahan province indicated that this species was distributed in the most vineyards, but was highly abundant in more humid conditions.
A. Azari, M.r. Khajehpour,
Volume 9, Issue 3 (fall 2005)
Abstract
The appropriate planting pattern of safflower in summer planting might be different from the planting pattern suitable for spring planting, and this has not been determined under Isfahan environmental conditions. A field experiment was conducted in the summer of 2000 at the Agricultural Research Station, Isfahan University of Technology, using a randomized complete block design with a split plot layout and three replications. Main plots consisted of three row distances (30 cm flat and 45 and 60 cm on bed), and sub-plots included three planting densities (30, 40, and 50 plant m-2). The experiment was planted in June 13 using local safflower variety of Isfahan, named Koseh. Leaf area index, number of heads per branch, number of seeds per head, 1000-seed weight, seed yield per plant and harvest index were not significantly effected by row distance. Increase row distance significantly enhanced most developmental stages and increased number of branches per plant and per square meter, but significantly decreased number of heads per plant and per square meter and seed and petal yields. The highest seed and petal yields (3841 and 373 kg per ha, respectively) were obtained with 30 cm row distance. Plant density had no significant effect on number of branches per plant, number of seeds per head, 1000-seed weight and seed yield per plant and per unit area. Plant density significantly enhanced most developmental stages and increased leaf area index, number of branches and number of heads per square meter, but significantly decreased number of heads per branch and per plant, petal yield and harvest index. The highest seed yield without petal clipping (4341 kg per ha) was obtained with 30 cm row distance and 50 plants m-2 treatment. The results obtained in this experiment indicate that this planting pattern might be appropriate for summer planting of safflower under conditions similar to this experiment.
M. Latifian, H. Seyedoleslami, J. Khajehali,
Volume 9, Issue 3 (fall 2005)
Abstract
In 1997, in two vineyards of Isfahan university of technology and Zobeahan in Isfahan, the density fluctuations of Arboridia kermanshah Dlabola and their injury symptoms were studied. In each vineyard three leaves of each of ten randomly selected vines were sampled weekly. Nymphs in different instars were counted directly and rate of injury symptom (leaf discoloration) was determined with planimeter. Special cages were used to determine rate of injury symptom for each nymphal instar in comparison to each other. Rate of injury symptoms and nymphal density indicated two peaks through growing season until harvest. Tolerance threshold for A. kermanshah nymphs was determined 80 first instar nymphal days or presence of 11-12 first instar nymphs and feeding for seven days. With increase of nymph densities, damage symptom increased rapidly.
F A. Frouzandeh Shahraky, M. R. Khajehpour,
Volume 9, Issue 4 (winter 2006)
Abstract
Under irrigation and in double-cropping system, a large amount of plant residue remains after harvest that along with the limited time for residue decomposition and complete seedbed preparation, necessitates reduced tillage and special residue management. In the present study, the effects of various seedbed preparation methods on vegetative growth, yield components and seed and oil yields of sunflower (Euroflor hybrid) were studied in a barley-sunflower cropping system during 2001 at the Agricultural Research Station, Isfahan University of Technology. Three residue management treatments (standing, partly removed and burned) along with five tillage systems (moldboard + disk chisel + disk disk moldboard and furrower as the minimum tillage) were laid out in a split-block design with three replications. Burning residue treatment significantly increased plant dry weight at various developmental stages and also head diameter. Number of seeds per head, 1000 seed weight, harvest index, and oil yield were non-significantly higher in the burned residue treatment. Seed yield was significantly higher in the burned and partly removed residue treatments. Moldboard + disk and chisel + disk treatments significantly produced higher plant dry weight at various developmental stages, head diameter and seed yield. Number of seeds per head, 1000 seed weight, harvest index, and oil yield were non-significantly higher in these treatments. Minimum tillage ranked the lowest for these traits. The results of this experiment indicate that chisel + disk treatment with the partly removed residues might be an appropriate seedbed preparation method in a barley-sunflower double planting under conditions similar to this experiment.
M. Bagheri Mofidi, M. Bahar, H. Shariatmadari, M. R. Khajehpour,
Volume 10, Issue 2 (summer 2006)
Abstract
To investigate drought tolerant isolates of rhizobial symbioant of lentil (Lens culinaris L.), 12 soil samples were collected from cultivated and non-cultivated area of Golestan, Chaharmahal-O-Bakhtiari and Isfahan provinces. Local cultivars of lentil including Binam Dorosht, Ghazvini and Faridani were planted in each soil sample. After 10 weeks, a total of 324 rhizobial isolates were recovered from root nodules of the lentil plants. Evaluation of the ability of the isolates to grow at different concentration of salt showed that all isolates grew normally on 200 mM NaCl and only 20% was determined as salt tolerant isolats(>400mM). Among the isolates RL249 was classified as superior salt tolerant strain due to growing on 600 mM salt. The drought tolerance of the isolates was also examined, using PEG6000. In general, the salt tolerant isolates were also drought tolerant, however their tolerance to salinity and drought is not related to their geographical origin. In a randomized split factorial design with three replications, the effectiveness of tolerant isolates(RL249 and RL211) and a sensitive strain (RL 77) was compared on two cultivars of lentil (Binam Dorosht and Faridani) under water stress treatments with the consumptions of 50, 75,90 and 98% of soil available water. Although nodulation rate was reduced in both cultivars as the consequence of drought stresses, plants of Binam Dorosht cultivar showed high nodulation rate due to the increased fresh weight of the roots. Despite the fact that RL249 was identified as a superior nodulating and salt/drought isolate, however nodulation efficiency was decreased significantly under water stress treatments with more than 50 % of soil available water.
S. Fallah, A. Ghalavand, M. R. Khajehpour,
Volume 11, Issue 40 (summer 2007)
Abstract
It is necessary to use organic fertilizers and decrease chemical fertilizers consumption to reach sustainable agriculture. Thus, to study the effects of manure incorporation methods, and integrated effects of poultry manure with chemical fertilizers on the grain yield and yield components of maize, an experiment was conducted in 2004 at the Agricultural Research Farm of Lorestan Weather Department, 30 kms northeast of Khorramabad. The treatments were arranged in a split plot layout based on randomized complete block design with four replications. The main plots consisted of incorporation of fertilizer with soil by furrower or disk. The subplots included T0: control (no consumption of fertilizer and poultry manure) T1: 200, 100, and 100 kg ha-1 of nitrogen, phosphorus, and potassium, respectively T2: 80% of T1+ 4 ton ha-1 of poultry manure T3: 60% of T1+ 8 ton ha-1 of poultry manure T4: 40% of T1+ 12 ton ha-1 of poultry manure T5: 20% of T1+ 16 ton ha-1 of poultry manure and T6: 20 ton ha-1 of poultry manure. The results showed that incorporation of fertilizer by furrower, compared with disk, led to significant increase in plant height, 1000 seed weight and grain and biological yields. However, there were not significant differences in the number of seed per ear and harvest index between the two fertilizer incorporation methods. Fertilizer treatments caused significant increase of the treats mentioned except for the harvest index. The interaction effects were not significant for any traits. T5 treatment produced the highest grain yield, and was significantly different from T0, T1, T3 and T6 treatments. The differences between T1 (chemical nutrition system) and T6 (organic nutrition system) were not significant either. Effectiveness of integrated poultry manure and chemical fertilizers on maize yield components was higher than either poultry manure or chemical fertilizer. The results of this experiment indicated that incorporation of 16 ton poultry manure + 40, 20 and 20 kg ha-1 N, P and K with furrower might be appropriate for maize prodution under conditions similar to this experiment.