JOURNAL OF CROP ECOPHYSIOLOGY (AGRICULTURE SCIENCE)
Year:2017 | Volume:11 | Issue:1 (41) |Papers Count:14

To investigate the effect of nitrogen and phosphorus nutrients from organic and chemical fertilizers sources, on their efficiency in purslane, a field experiment based on complete randomized block design was conducted at the Research Farm of Shahrekord University in 2014. Treatments were 13 t.ha-1 broiler litter (T1), 14.4 t.ha-1 broiler litter (T2), 39 t.ha-1 cattle manure (T3), 16.8 t.ha-1 cattle manure+150 kg.ha-1 urea (T4), four chemical fertilizer levels equivalent to organic manure treatments, 260+86 kg.ha-1 urea +triple super phosphate, respectively (T5), 287+100 kg.ha-1 urea+triple super phosphate, respectively (T6), 260+200 kg.ha-1 urea+triple super phosphate, respectively (T7), 260+100 kg.ha-1 urea+triple super phosphate, respectively (T8) and control (T0). The results showed that T2 treatment produced 8345 kg.ha-1 of dry matter as compared with those of other fertilizer treatments (P<0.05). This indicate that nitrogen and phosphorus efficiencies in T2 treatment were significantly higher than other treatments (P<0.05). In the mean time, nitrogen efficiency in T5 and T7 were not significantly different. However, phosphorus efficiency in T2 (52.6 %) indicated significant difference as compared with the other treatments. Nitrogen physiological efficiency of treatment in T2 (35.02 kg.kg-1) and T8 (31.6 kg.kg-1), and also P physiological efficiency in T1 and T5 were not significantly different. As a whole, the higher N physiological efficiency and also physiological efficiency of phosphorus in broiler litter reflect the ecological role of organic manure application in the production of purslane. This can also help environmental protection, as well as preventing loss of resources and phosphorus accumulation in the cropland soils.

Drought stress is one of the major factors limiting crop yield in dry-lands. To investigate the effect of sources and different rates of selenium on physiological traits, yield and yield components of wheat and barley in dry lands a factorial experiment based on complete randomized block design with three replicates was carried out at the Research Station of Islamic Azad University, Arak Branch, in 2014-2015. Experimental factors were selenium sources with two levels, (sodium selenate and sodium selenite), selenium rates with three levels, (0, 18 and 36 g.ha-1) and two crop plant (wheat and barley). The result showed that, foliar application of wheat with 18 g.ha-1 sodium selenite increased the grains per spike by 9.4% as compared to control and foliar application of barley with 18 and 36 g.ha-1 of sodium selenite increased the grains per spike by 8 and 12%, as compared to control, respectively. Two times foliar applications of these two plants with sodium selenate and sodium selenite increased their relative water content. Foliar application by 18 g/ha of selenium increased the grain yield from 1776.31 kg.ha-1 in control to 1889.92 kg.ha-1, while grain yield was decreased (about 1539.62 kg.ha-1) as compared to control when 36 g.ha-1 of selenium was used. It could be concluded that foliar application of 18 g.ha-1 selenium as sodium selenite or sodium selenite in wheat and barley during stem elongation and emergence of spike increases grain yield in dry land condition.

To Study of the effects of biological and chemical fertilizers applications on quantitative and qualitative traits of potato (Kaiser cultivar), a factorial experiment based on a randomized complete block design with three replications was performed in Lordegan city in Iran during 2014. The fertilizers used were chemical nitrogen and phosphorus fertilizers with two levels (nitrogen, 150 kg.ha-1 from urea resource and Phosphorous, 120 kg.ha-1 from super phosphate triple) and biological fertilizers were (nitroxin, vermicompost and phosphate barvar 2) each with two levels. The results showed that the use of nitroxin, vermicompost and phosphate barvar 2 and nitrogen and phosphorous fertilizers affected starch content, plant height, number of main stem per plant, LAI, total dry/fresh matter, the largest and smallest tuber diameter, number of tuber per plant and tuber yield, significantly. The highest tuber yield was observed by using nitroxin, vermicompost and phosphate barvar 2. Results of this research also showed that use of biological and chemical fertilizers affected vegetative traits that are related to qualitative and physiological indices. In spite of these promising effects of chemical and biological fertilizers on quantative and qualitative traits of potato, application of triple super phosphate along with biological fertilizers did not affect quality and quantity of potato. The highest starch percentage in dry matter of tuber (75.27%), number of main stem per plant (6.37), diameter of largest (185.75 mm) and smallest tuber (58.08 mm), tuber yield (33317.5 kg.ha-1), were produced by the use of biological fertilizers. Overall, results showed that the use of biofertilizeres may improve the measured traits of quantity and quality of caeser cultivar of potato and obtain the highest yield.

Effects of phosphate fertilizer and pseudomonas putida strains on the quantity and quality of forage of berseem clover as a second crop was studied in a factorial field experiment using randomized complete block design with three replications at Fooman, Guilan province, Iran. Treatments consisted of phosphate fertilizer with three levels (0, 75 and 150 kg/ha as triple super phosphate) and Pseudomonas putida strains with four levels (M21, M5, M168 and control). The results showed that use of phosphate fertilizers increased the soil pH during growing season while bacterial inoculation adjusted soil pH. The bacterial inoculation increased amount of crude protein, digestible protein, acidic and alkaline phosphatase activity compared to non-inoculated treatment, but it decreased crude fiber of the forage. Clover forage yield, protein yield and phosphorus content of foliage also were influenced by the interaction of bacterial strains and phosphate fertilizer. The highest forage and protein yield were obtained by using strain M5+150 kg P ha-1. Significant increases in forage and protein yield were found to be 16.49% and 8.01%, respectively, as compared with non-inoculated treatment. Based on the result of this experiment, application of 150 kg P ha-1 and Pseudomonas putida strain M5 inoculation can be used to obtain highest forage yield and quality of berseem clover as second crop in the experimental site.

To study the effects of drought and foliar applications of salicylic acid and chitosan on some physiological traits and oil yield of safflower under drought a split plot experiment with three replications based on a randomized complete block design was conducted at the University of Zabol, Iran. Treatments were three levels irrigations at 25, 50 and 75% of soil available water assigned to main plots, and four levels of foliar applications of salicylic acid and chitosan (control, 0.424 g/liter of salicylic acid, 5 g/liter of chitosan and mixed application of salicylic acid and chitosan) to sub-plots.Water stress reduced oil yield and phosphorus, potassium and calcium contents of shoot. Oil yield was decreased with increasing drought stress by 11% as compared to that of control. Severe water stress also increased the amount of sodium in seed, but its effects on nitrogen and iron control of shoot, membrane stability index and relative humidity were not significant. Foliar application of salicylic acid and chitosan increased macronutrients (nitrogen, phosphorus and potassium) and micronutrients (calcium and iron). Seed oil yield was not affected by foliar spray. In general, combined application chitosan and salicylic acid on traits under study was effective. It can be suggested that combined application of chitosan and salicylic acid could be effective in growing safflower at this region.

To evaluate the effect of humic acid on activity of antioxidant enzymes in castor bean a split plot experiment based on completely randomize block design with four replications was carried out at Islamic Azad University, Karaj Branch in 2014.Treatments were irrigation with three levels [irrigation at 80% of field capacity (S1) (normal), irrigation at 65% of field capacity (S2) (mid stress) and irrigation at 50% of field capacity (S3) (high stress)] assigned to main plots and humic acid with four levels (without foliar application, one time, twice and three times foliar application) to sub plots. In this study traits like seed yield, 100 seed weight and antioxidant enzymes were estimated. The results showed that the effect of humic acid was significant at 1% level on 100 seed weight and activity of antioxidant enzymes. Mean comparisons indicate that foliar application of humic acid could compensate relative effect of water deficit. It was also revealed that the rate of superoxide dismutase, glutathione peroxidase and catalase were increased with three times of humic acid foliar applications by 38.8, 34.75 and 37.88 percent under mid stress drought and 26.63, 41.15 and 43.14 percents under high stress drought as compared to control, respectively. Overall, it can be said that use of humic acid have different physiological effects. Humic acid not only increases seed yield of castor bean it also have a positive role in reducing water deficit effects and increasing activity of antioxidant enzymes.

The present experement was conducted as a factorial experiment based on RCBD with four NaCl levels (0, 50, 100 and 150 mM) levels and two savory native clones (Tabriz and Hamadan) with three replications, to investigate the effects of Nacl salinity on some physiological (essential oils, chlorophyll, proline, soluble sugars, ion leakage, Na+ and K+ content) and growth characteristics of savory. The results revealed that there was significant interaction effects between salinity and clone on chlorophyll a content of the plant. The highest chlorophyll a content in both clones was recorded in the control plants. Root dry weight, Na+ and K+ content, K+ /Na+ ratio, soluble sugars and ion lekage were affected by NaCl salinity. The highest amounts of stem and leaf dry weights, essential oils contents, proline and chlorophyll b content, were influenced by both clone and salinity levels. The highest stem dry weight, essential oil and proline contents belonged to Tabriz clone.The highest leaf dry weight and chlorophyll a + b contents were produced by Hamadan clone. The highest amont for some other traits, like root, stem and leaf dry weights, as well as for K+ and K+ /Na+ ratios, were observed in the control treatment. The highest Na+ accumulation were recorded in 150 mM NaCl treatment. It was also observed that with increasing salinity levels, proline content was concomitantly increased. The hieghest ion leakage, soluble sugars and proline amounts were belonged to 100 and 150 mM salinity levels. Considering the variation patterns for the traits studied, it seems that the salinity levels in both clones routinely affected the growth and physiological characteristics of the plants. It can be concluded that to achieve economical yields of savory and proper physiologyical traits we have to select salt tolerant clones to suit saline environments.

Electrical conductivity of wheat cell sap and chlorophyll concentration of its leaves under drought stress and application of zeolite were evaluated in a split plot experiment, by using a RCBD with three at Arak Payam-Noor University in 2010. Treatments were four levels of water stress (I0=control irrigation, I1=irrigation at 85% of I0, I2= irrigation at 70% of I0, I3=irrigation at 55% of I0) assigned to the main plots and four levels of zeolite applications (Z0=without zeolite application, Z1=3 t.ha-1, Z2=6 t.ha-1, Z3=9 t. ha-1) to the sub plots. Sub plots consisted of 4 rows of 5 m long spaced 50 cm apart and 20 plants per meter on the rows. In this study traits like peduncle length, awn length, number of spike per m-2, grain yield, electrical conductivity by using water with 50 and 60oC were assessed. Results indicated that intraction effect of water stress and zeolit application on number of spike per m2, seed yield, and electrical conductivity at 50 and 60oC water were significant. Mean comparisons of intraction effects showed that electrical conductivity of water with 50 and 60oC (447 and 476 respectively) resulted in the least detrimental effect on cell membrane. Results also revealed that electrical conductivity at control irrigation (554 ms.cm-1) and application of 9 t.ha-1 of zeolit produced highest seed yield (4901 kg.ha-1) at wheat.

Tribenuron-methyl is commonly used for post emergence control of broad leaf weeds in wheat fields. In order to survey suspicious resistant weeds in wheat fields to this herbicide thirty-eight fields of Kermanshah province were investigated during 2012- 2013. Seeds of suspected resistance of wild mustard were gathered and tested in a randomized complete blocks design experiment with three replications. First, for early detection of herbicide resistance, the suspected population was screened using discriminating dose of tribenuron-methyl. Determining of the resistance degree was conducted by whole plant bioassay tests using dose-response curves. The resistance mechanisms were assayed by molecular methods, especially using the ALS gene cloning by PJET1.2/blunt Vector. For susceptible populations, the concentration required for complete control was 10.4 g ai ha-1 tribenuron-methyl. Also, in screening tests 50% of populations as resistant populations were identified. According to the Beckie and Tardif, it was found that 57.8% of these population did have a very high degree of resistance, 31.5% with high resistance and 10.5% with low resistance degree.GR50 of the resistant weeds was also increased as compared to sensitive weed, which indicates resistance in this province, Thus to control the resistant populations Z15, this amount increased to 1309 g ai ha-1.The results of DNA sequencing showed that mutation by replacing proline amino acid at position Ala122 causes resistance based on target-site mutation.

Weed identification is considered the most fundamental task in weed management.It would be possible to decide on specific methods of weed control through availability of weed information in a particular location, otherwise applying different methods of control will not show satisfactory effects. To evaluate the species diversity and population indices of weeds in dry-land winter chickpea fields at four counties of Kermanshah province, 30 fields were investigated in 2015. The sampling was done based on W method at twenty points in each field. All weed species in each quadrate were identified and counted on the basis of genus and species. The indices of density, frequency, uniformity, abundance index, and relative diversity for each species were calculated and 44 weed species belonging to 22 different families were identified: 18% of families belonged to Asteraceae, 13% to Fabaceae, 11% to Brassicaceae, and 9% to Poaceae of all the weeds identified 89 percent of belonged to dicotyledons and 11 percent to monocotyledon. The broad leaf weeds of winter dry-land chickpea of Ravansar county based on dominance were common chicory (Cichorium intybus), european bindweed (Convolvulus arvensis), cow cockle (Vaccaria pyramidata) and stichy willie (Galium tricornatum), respectively. In Kermanshah county the european bindweed (Convolvulus arvensis), common chicory (Cichorium intybus), stichy willie (Galium tricornatum) and yellow goatsbeard (Tragopogon major), were the dominant weeds, respectively. Also, at Dalahoo county the common chicory (Cichorium intybus), stichy willie (Galium tricornatum), cow cockle (Vaccaria pyramidata) and wild licorice (Glycyrrhiza glabra), were dominant weeds, respectively. In west Islamabad county the dominance was related to common chicory (Cichorium intybus), European bindweed (Convolvulus arvensis), wild mustard (Sinapis arvensis) and yellow goatsbeard (Tragopogon major), respectively.

Integrated weed management in canola (Hyola 401) was studied in an experiment conducted in 2014-2015 growing season in“Kohghilooyeh and Boyer Ahmad”, Iran.The experiment was performed in strip split plots based on randomized complete block design with three replications. Tillage systems with three levels (conventional tillage, reduced tillage and no-tillage) assigned to main plots, and herbicide applications at four levels consisted of trifluralin (1200 g ai ha-1, 48% EC), quinmerac+metazachlor (1040 g ai ha-1, 41.6% SC), clopyralid (180 g ai ha-1, 30% SL) +setoxydim (375 g ai ha-1, 12.5% EC), clopyralid (180 g ai ha-1) +haloxyfop-R methyl ester (81 g ai ha-1, 10.8 % EC) and weed free treatments. Results showed that weed density and dry weight reductions were 76.84% and 68.08% in reduced tillage system+quinmearc+metazachlor application, respectively. It was, also, observed that treatment influenced plant height, biological yield, harvest Index, silique number per plant, seed number per silique, 1000-seed weight and seed yield. The maximum yield (3226 kg.ha-1) was obtained by using reduced tillage+quinmearc+metazachlor application. Therefore, it would be concluded that reduced tillage+quinmearc+metazachlor was the best treatment to control weed and achieve high canola seed yield. The results, also, revealed that use of clopyralid+ Haloxyfop-R-methyl ester+no-tillage resulted in lowest yield (467 kg.ha-1) So, it was considered as inefficient treatment.

To evaluate the reduced concentration effect of Trifluralin (Treflan EC 33%) on common lamsquarters (Chenopodium album L.) and redroot pigweed (Amaranthus retroflexusL.) in potato (cv. Agria) a field experiment based on randomized complete design with three replications was carried out at the Agriculture and Natural Resources Research Station of Ardabil during 2013. Treatments were concentration of Trifluralin (0.125, 0.25, 0.5, 1, 2 and 4 Lit a.i/ha) without weed control and weeding out (as control). Sampling of weeds were performed before and after flowering of potato.Statistical analysis showed significant differences of reduced concentrations of Trifluralin on reduction of both lamsquarters and pigweed in the field. The highest reduction in percentages of weed densities, before and after flowering (91.94 and 90.34 percent, respectively) were achieved by using 4 Lit a.i/ha of Trifluralin. Application 4 Lit a.i/ha of Trifluralin at before and after flowering reduced common lamsquarters density by 87.13 and 86.04 percentages, respectively. Application 4 Lit a.i/ ha Trifluralin at befor and after flowering reduced pigweed density by more than 90 percent. Experimental results also showed that different concentrations of Trifluralin had significant effect on mean tuber weight per plant, and potato tuber yield. The highest mean weight of tuber per plant, yield per plant and potato tuber yield was obtained at 2 Lit a.i/ha Trifluralin concentration, while it was not significantly different from that of 4 Lit a.i/ ha. Generally, application of 2 and 4 Lit a.i/ha Trifluralin incereased tuber yield by 51.85 and 50.74 percents respectively.

To investigate the effect of weed interference on the yield and yield components of rice an experiment was conducted in 2014 at Amol and Mahmoudabad cities in Mazandaran. The experiment was performed in a randomized complete block design with 12 treatments and three replications. Treatments to control weeds were of two types. The first treatment consistsed of controling weeds 10, 20, 30, 40, and 50 days after rice transplanting and then weeds interfered with plant during rest of growing season. A whole season weed control was used as check. The second type treatment at weed interference until 10, 20, 30, 40, and 50 days after rice transplanting and then weeds were controlled during rest of growing season. A whole season interference treatment was used as a weed infested check. The results of variance analysis showed a significant difference for grain yield in either weed free or weed infested treatments between two places. Weed control and interference (except panicle number and biological yield) significantly affected grain yield, grain numbers per panicle and 1000 grain weight. The highest grain yield (3010.83 kg.ha-1) belonged to weed control during whole growing season and lowest grain yield (2075 kg.ha-1) was obtained from weed infested check. Weed infested check resulted in lower grain yield (by 8.31%), panicle number (by 8.33%) and grains number per panicle (by 10.26%) as compared to the control. The critical period of weed control, based on the amount of 5 and 10 percent of yield losses, were fitted by Gompertz and Logestic regression to weed infested weed free treatments, respectively. The results showed that the critical period of weed control in Mahmoudabad region occurred during the days of 22 to 59 and 27 to 36 (from early to end of tillering) based on 10 and 5 percent of yield loss, respectively. The critical point was calculated to be 32 days after transplanting. The critical period for Amol region occurred during days of 15 to 54 and 20 to 37 (from early to end of tillering) based on 10 and 5 percent of yield loss, respectively. The critical point was calculated for day 25 after transplanting. In conclusion, the critical period of weed control seems to begin earlier in Amol than in Mahmoudabad and it also had a longer range.

A field experiment was conducted at Rasht, in 2014, to investigate controlling weeds in native Hashemi cultivar paddy fields by different methods of herbicide applications and inoculated withAzotobacter chroococcum. The factorial experiment based on a randomized complete block design with three replicates was performed.Factors were Azotobacter application with two levels (inoculation with or without Azotobacter chroococcum) and weed management regimes with six levels (pretilachlor plus a supplementary hand weeding, bensulfuron methyl plus a supplementary hand weeding, and pretilachlor+bensulfuron methyl plus a supplementary hand weeding, hand weeding during rice growing period+no herbicide, un-weeded during rice growing period+no herbicide). Results indicated that paddy rice yield was significantly increased by 16% afterAzotobacter chroococcum inoculation. Rice paddy yield was significantly reduced in un-weeded plots compared to hand weeded and herbicide treated plots. ANOVA also revealed that there was no interaction effect between Azotobacter chroococcumapplications and weed management regimes on paddy and biological yields, indicating that the herbicides had no adverse effect on Azotobacter efficiency in promoting growth and paddy yield of rice. Weed dry weight was reduced by 88, 91, 92, and 94 percentages in weeded plot and plots treated with pretilachlor, bensulfuron methyl, and pretilachlor+bensulfuron methyl, respectively, compared to un-weeded plots.Azotobacter chroococcum inoculation had no significant effect on weed biomass. Overall, the result of this experiment confirmed the feasibility of chemical weed control in paddy fields inoculated withAzotobacter chroococcum.