Iranian Journal of Field Crops Research
Year:2006 | Volume:4 | Issue:1|Papers Count:20

Pulse, as the second source of human nutrition, benefits from great agronomic and nutritious features. These plants are amongst the most important crops which are full of protein and are widely cultivated all over the world; having the ability to adapt to different climate measures ranging from mild to hot and from moist to very dry. The other noteworthy trait of these crops is their talent to coexist with nitrogen fixation bacteria available in the soil which plays an important role in soil fertility and sustainability. For the previously mentioned reasons and many more, pulses have been extensive fields of research. With the substitution of legumes with fallow in the wheat-fallow cropping system, great success in product stability has been gained. Having emphasized on the importance of the issue, the first national pulse symposium with the aim of investigating the opportunities and threats facing the development of pulse in Iran was held on 20-21 Nov. 2005 at Research Center of Plant Sciences, Ferdowsi University of Mashhad in collaboration with many scientific, research and administrative institutions. This paper aims at sketching the overview of the strategic research direction in Iran by analyzing the published papers presented in this conference and will provide the key points mentioned in the final conference manifestation.

Isabgol (Plantago ovata) is an important medicinal plant in world that has more medicinal uses. Germination stage is an important growth plant stage that often affected by environmental stress including water and salinity stress. In order to study germination characteristics of Isabgol in water and salinity stress conditions two laboratory's experiment were conducted. The two experiment were conducted in completely randomized design with 3 and 4 replications for salinity and water stress, respectively. The treatments, for salinity and water stress were six potential (0, -2, -4, -6, -8 and -10 bar) of NaCl and four potential (0, -4, -8 and -12 bar) of PEG respectively. Results of two experimental showed that increasing water and salinity stress decreased significantly germination rate, germination percentage, plumule and radicle length (P<0.01).Zero to -8 bar was the best range for seed germination on Isabgol. The results showed that among of total characters, plumule length is more sensitive to water and salinity stress. It seems that seed germination on Isabgol has more tolerance in salinity stress condition than water stress condition.

In order to evaluate the critical period of weed control in Cumin, an experiment with Complete Randomized Block Design and three replications was conducted in experimental field of Faculty of Agriculture, Ferdowsi University of Mashhad, During 2004-2005 growing season. Treatments included different combinations of weed free and weed infested periods (20, 30, 40 and 80 days after germination) plus weedy check and weed free check. Critical period weed control was evaluated with Gompertz and Logistic functions. Traits measured were yield and yield components, harvest index of cumin and also number and weight of weed species. Results showed the critical period was between 24-38 days after germination. With increasing interfering period at early or late growth stages of cumin, the economic yield was reduced. By extending weeding periods at early stage of growth or during the growth period, dry weight of weeds were reduced, while extending weeding period at the end of growth stage and also weed free during growth period, early or late stages of growth had no significant effects on yield components except on number of umbels per plant. Harvest index was positively affected by early weeding. It appears that early weeding was somehow more effective on yield components for cumin.

Optimal germination and plant establishment is an important problem for agricultural productivity in arid and semi-arid areas. Priming is an approach for increasing plant establishment in undesirable conditions. This research was conducted in a laboratory at the College of Agriculture, Ferdowsi University of Mashhad. Two lentil genotypes (MLC198, MLC4), two osmoticum as priming agents (pEG, NaCl) and three osmotic potential for each osmoticom (-4, -8 and -12 bars) were used in this study. Germination test was conducted in two conditions (water stress and non water stress). The result showed that PEG was more effective than NaCl for lentil seed priming. Within the applied osmotic potentials, -8 bar of PEG and -4 bar of NaCl were the best in promoting seed germination. MLC4 showed better response to priming compared with MLC198 genotype. Under non water stress conditions, different parameters of germination were in state of affairs.

Trends in cultivated area, yield and production of wheat, barley and rice as the main cereal crops of Iran were studied during 1350-1382 using time series analysis and the situation of future were predicted for 1382-1400 period. The results showed that country-level cultivated area of cereals is leveled off after and initial increase and the current area under cultivation will be maintained until year 1400. However, cultivated area of irrigated wheat and rice will be increased slightly. During the last 32 years cereals yield is increased considerably. Mean annual rate of yield increase was much higher for irrigated cereals (62.5kg year-1) and rice (69.7kg year-1) compared to rainfed cereals (12.6kg year-1), this incremental trend will be continued towards year 1400. The increase of cereal yield in spite of constant cultivated area is led to increase in total production and it was predicted that total cereal production of country will be exceed 26 million tons in target year of 1400. However, per capita cereal production which was at its highest in the mid years of the study period, was decreased later and at present is about 310kg which is not much different from the baseline year (1350). Per capita production of cereals will remain unchanged until year 1400 because of high predicted population growth rate.

In order to study different of velvetleaf (Abutilon theophrasti Medicus) and simultaneous planting. date of (Glisine max (L.) Merril) and velvetleaf on yield and yield components of soybean, an experiment was conducted in 2004, at Ferdowsi University of Mashhad, College of Agriculture Experimental Station. The type of experiment was Completely Randomized Design in factorial arrangement with 3 replication in witch velvetleaf density (0, 2, 4, 8, plan/m2) and planting date of soybean and velvetleaf at 3 levels (April 23, May 13 and June 3) were used. Study of grain yield and yield components indicated that increase in velvetleaf density due to significant decrease in pod and grain number of soybean plant caused significant reduction of grain yield. Different planting dates had significant effect on yield and all yield components and delaying planting date, resulted in a significant reduction of yield components and yield. The interaction between density and planting date, was based on number of pod in plant and number of grain in soybean pod but it had no significant effects on grain number per plant, 1000 grain weight and grain yield of soybean.

In order to study the effect of different densities of intercropping cumin and chickpea, an experiment was conducted in the farm of Agriculture College of Mashhad. This experiment was conducted as a strip design based on RCBD with four replications. Main plots included weed control treatments (I-one time control in growing season on emergence stage. II-without control) and subplots included 5 different densities (1-120 pl/m2 cumin, 11-90 pl/m2 cumin + 15 pl/m2 chickpea, III- 60 pl/m2 cumin + 30 pl/m2 chickpea, IV- 30 pl/m2 cumin + 45 pl/m2 chickpea, V- 60 pl/m2 chickpea). The results showed a significant difference in all growth indices in all one time weed control and without weed control treatments. As the densities decreased, both crop's growth indices decreased. The decrease of chickpea yield in all densities in both weed control treatments, showed significant difference. Crop growth rate (CGR) and leaf area index (LAI) in cumin despite of chickea has affected positively by intercropping. Total land equivalent ratio (LER) in all treatments was more than one and partial LER only in 90 pl/m2 was more than one that shows the positive effect of intercropping on cumin yield.

In recent years, allelopathy has received special attention by scientists in integrated weed management (IWM). To study the effect of different amount of Knotweed residue on emergence and growth of tomato and corn seedlings, two experiments were conducted at, Ferdowsi University of Mashhad. The type of design was completely randomized, with 5 and 4 replications for tomato and corn, respectively. The Knotweed residues (zero, 0.33, 0.67, 1 and 1.33% (W/W) were added to the pot soil. Seedlings showed different response to different amount of Knotweed residues. Increasing residues increased the emergence percentage of tomato but decreased corn emergence. Increasing residues resulted in increasing 33.9% and 39.3% of leaf area in tomato and corn, respectively. Knotweed residues resulted in 36.5% and 46.7% increase in shoot dry matter of tomato and corn, respectively. Increasing dry matter resulted in increasing up to 67.2% and 54.5% root dry matter of tomato and corn, respectively. Different doses of Knotweed had stimulatory effect on emergence of tomato but had inhibiting effect on corn. Knotweed residues had stimulating effect on seedling growth of corn and tomato. Root dry matters of both species were more influenced by Knotweed residue than foliage.

In order to investigate species and functional diversity and community structure for weeds in wheat and sugar beet fields in different provinces of Iran, this study was conducted by using data from a previous projects on weed control conducted by Ministry of Jihad Keshavarzi. Total number of weed species were 72 and 52 species in wheat and sugar beet, respectively. In the wheat fields, Poaceae and Asteraceae showed the most diversity amongst monocotyledonous and dicotyledonous groups. In the sugar beet fields, Poaceae and Brassicaceae were the most diverse family amongst monocotyledonous and dicotyledonous groups. Provinces were grouped in three clusters for functional weed groups in wheat and sugar beet fields (similarity 75%). Tehran and East Azerbaijan had the highest similarity percentage (71%) amongst the provinces for weed diversity in wheat. In sugar beet fields, the highest similarity percentage was observed in Hamedan and Kohkiloyieh va boier-ahmad (71%), Ilam-Ardabil and Khoozestan-Ardabil provinces showed the lowest.

In order to investigate the effect of different irrigation intervals and plant densities on yield and yield components of two fennel landraces, an experiment was conducted at the agricultural research station, Ferdowsi University of Mashhad in 2003 and 2004. For this purpose a double split plot experiment based on a Complete Randomized Block Design with three replications was used. Treatments included three irrigation intervals (10, 20 and 30 days), two fennel landraces (Khorasan and Kerman) and four plant densities (40, 50, 67 and 100 plant per m2). Row spaces were kept constant (25 cm) and plant density were adjusted in row spaces. Results indicated that irrigation affected vegetative and reproductive organs, significantly. With increasing irrigation intervals, plant height, dry matter of stem, total dry matter of plant, lateral branches per m2, umbels per m2, umbels per plant, fertile umbels per main stem, umbels per lateral branch, umbelets per umbel, 1000-seed weight and grain yield were decreased, but main branches per m2 and grain number per umbelet did not show a constant trend. Khorasan landrace had more plant height and 1000-seed weight than Kerman landrace, but main branches per m2, lateral branches per m2, umbels per m2, umbels per main branch, umbelets per umbel, grain number per umbelet and grain yield in Kerman landrace were higher than Khorasan landrace. Two landraces showed no differences in dry matter of stem weight, total dry matter of plant, umbels per plant and umbels per lateral branch. With increasing plant density, umbels per plant, umbels per main branch, umbelets per umbel and grain number per umbelet decreased, significantly. Density had no significant effect oil 1000-seed weight. With increasing density, dry matter of stem, total dry matter of plant, main branches per m2, lateral branches per m2, umbels per m2and grain yield increased, but umbels per lateral branch showed no constant trand. Our results showed that the maximum grain yield was obtained in Kerman landrace with 10 days irrigation interval and 100plants per m2.

In order to study the effect of terminal drought stress on some quantitative traits and tolerance of three kabuli chickpea genotypes, an experiment was carried out at Kohdasht, Iran, on a loam soil using, a split plot experimental design with three replications. Three sowing dates (autumn, winter and spring) were assigned to main plots and three Kabuli chickpea genotypes (ILC482,Greet and Hashem) to sub plots. Results indicated that delay in sowing date decreased dry matter (66%), and grain yield (89%). Grain yield reduction was mainly due to reduced number of pod/plant (60%), 100 seed weight (32%). Considering the stress tolerance index (STI) Greet had the highest grain yield under the optimum condition (1464 kg/ha) as well as under terminal drought stress condition (302 kg/ha). It also performed to be resistant to terminal drought stress and height temperature conditions, according to stress susceptibility index (SSI).

Liens tolerate environmental stresses utilizing is one of the applicable technologies in sustainable agriculture. Since occurrence of a suitable winter for studing and selection of cold/frost resistance on breeding materials is one year out of ten, therefore laboratory methods complementing field data provide a reasonable solution for this propose. This research was conducted in Khorasan Agri. Res. Center. Mashhad. Using RCBD in three replications during 1380-81. Treatments consisted of twenty promising genotypes of uniform regional yield trail (cold area). Genotypes suits low temperature regions will be introduced based on generated results from this investigation. Using crown freezing method, experimental genotypes were treated with -20. C temperature under controlled conditions. Survival percentage was computed. Results indicated that genotypes No.9 (C-78-9) and No.7 (C-78-7) had highest (98.33%) and lowest (66.67%) survival percentage respectively. The minimum Crown Moisture Content was detected in line No. 9 (C-78-9) and there was no significant difference for the same trait between genotype No.7(C-78-7) and other superior genotypes. A high negative correlation (r=-0.701) was observed between survival percentage after exposing to frost and crown moisture content. Ear primordia development stage was one of the characters which had also a significant correlation with survival percentage (r=-0.619). Significant correlation between survival percentage and days to heading (r=-0.207) and days to physiological maturity (r =-0.028) was not observed. Correlation between survival percentage and collected cold damage data from experimental fields over five low temperature regional stations was highly significant (r=0.416), therefore it may be concluded that Crown Freezing Method and subsequent computing of survival percentage is a reliable method for estimating wheat frost/cold tolerance in natural conditions.

Agroclimatic indices could be affected by climate change and evaluation of these indices under different climate scenarios provides a framework for further impact studies. Principal component analysis (PCA) and cluster analysis are proper methods for regional analysis of agroclimatic data and classification of climatic regions based on their similarities. Using 55 agroclimatic variables similarity of 36 meteorological stations around the country were studied under the present and future (2025 and 2050 as target years) climatic conditions. Results of PCA showed that 5 principal components including 1) temperature data, 2) precipitation data and winter minimum temperature, 3) winter maximum temperature, 4) winter precipitation and maximum temperature of spring, summer and autumn and 5) growth degree days during spring and winter and summer precipitation accounts for 97% of total observed variance. Results of cluster analysis showed that under the current climate, the studied stations were grouped in 10 clusters. However, number of clusters was reduced to 8 and 7 for the years 2025 and 2050, respectively. Based on the results it was concluded that under future climatic conditions agroclimatic diversity of Iran will be reduced considerably.