JOURNAL OF CROPS IMPROVEMENT (JOURNAL OF AGRICULTURE)
Year:2018 | Volume:20 | Issue:2 |Papers Count:18

Arizona Cypress (Cupressus arizonica L. ) and Thuja (Thuja orientalis L. ) are very important evergreenand mainly used as ornamental trees. This study was carried out in two independent experiments with themain purpose of evaluating of freezing tolerance of Arizona Cypress and Thuja with eight levels oftemperatures (control,-10,-15,-20,-25,-30,-35,-40 ℃ ) in a completely randomized design. Proline, electrolyte leakages, soluble carbohydrate and re-growth were measured. Results showed that proline andelectrolyte leakages were increased in both species. Re-growth percentage decreased dramaticaly in bothspecies with decreasing the temperature so that any re-growth was observed for Thuja and ArizonaCypress in the-30 and-20℃ , respectively. Interactions between soluble carbohydrate and temperaturewere not significant for Thuja but decreased significantly in Arizona Cypress. There was a negativesignificant correlation between re-growth, in Thuja (-0. 895) and Arizona Cypress (-0. 646) withtemperature. According to the results, Arizona Cypress was more susceptible to freezing compared toThuja.

Raising free radicals in root cells and thus increasing ions leakage is from destructive effects of salinity. In order to study the effect of zinc on the some of free radicals’ inhibitor enzymes (Catalase [CAT], Ascorbat Peroxidase [APX]) and decreasing induced damages of salinity stress by NaCl, in two cultivarsof olive (Olea europea L. ) (Frontoio and Conservollea), this pot experiment conducted, in factorialarrange and completely randomized design in three replication. In this experiment, a one-year seedling oftwo olive cultivars treated with nutrition solutions involved different levels of sodium chloride (0, 40, 80, 120 mM) and zinc (0, 1, 5μ molar) of zinc sulfate (ZnSO4. 7H2O). The results showed that withincreasing of salinity levels decreased root and leaf dry weight and plant height, but increased ion leakageof potassium and zinc in root and activity of CAT and APX enzymes in leaf, as well, using Zn, decreasedion leakage of potassium and zinc; whereas root and leaf dry weight, plant height, CAT and APX activityincreased. Based on the results, the greater the concentration of sulfhydryl groups in roots in Frontoiovariety compared to Conservolea was in acceptance with less leakage of potassium and zinc ions on theFrontoio compared to Conservolea. Therefore, the Frontoio variety was more resistant to salinity incomparison with Conservolea.

The present experiment attempts to evaluate the effects of organic, chemical, and biological fertilizers onplant and soil properties in saffron cultivation. It has been performed in the research farm of ShahedUniversity during the growing seasons of 2015-2016 as a factorial with two factors, based on arandomized complete block design with three replications. The first factor has been nitrogen fertilizer(urea) at three levels (0, 50, and 100 kg per ha), and the second, different types of non-chemical fertilizersat four levels (namely, control, vermicompost, PGPR bio-fertilizer with Pseudomonas and Bacillusbacteria, and integrated application of bio-fertilizer and vermicompost). Results show that fertilizertreatments have significantly changed the qualitative and quantitative properties of plant and soil. Amongthe fertilizer treatments, the integrated application of vermicompost along with 50 kg/ha chemicalfertilizers have had the largest significant growth yields, improving soil properties, as stigma dry yield, soil nitrogen content, soil organic matter, and available soil phosphorus have increased by 42. 6%, 66. 67%, 68. 39%, and 43. 75%, compared to the control, in this treatment. As such, it can be said thattotally-integrated application of vermicompost along with half of the recommended urea fertilizer iscapable of increasing the yield and improving soil properties in saffron cultivation.

With the aim of evaluat the effect of deficit irrigation stress on the growth, yield and physiological traitsof bitter apple (Citrullus colocynthis), an experiment has been conducted with three replications at theresearch field of University of Zanjan in 2016. Irrigation levels have been 100% of ETc with two deficitirrigations of 70% and 50% of ETc. Results show that deficit irrigation stress significantly reduce growthand fruit yield. The lowest leaf area, plant length, fruit number per plant, and fruit yield has been obtainedin deficit irrigation of 50% of ETc. Relative water content and chlorophyll content are significantlydecreased in response to increased deficit irrigation stress. Increase in deficit irrigation stress results inhigher peroxidase activity, electrolyte leakage, and proline accumulation, although there has been nosignificant difference between irrigation of 100% and 70% of ETc. Also, it has been observed that deficitirrigation of 70% of ETc saves 30% of irrigation water. Although it reduces fruit yield by 15. 5%, itcauses a 16. 8% increase in water use efficiency. Therefore, under limited irrigation water, it isrecommended to irrigate bitter apple plants at 70% of ETc irrigation to produce not only the same yields, approximately, but also save more water, as compared with 100% of ETc treatment.

To evaluate the effect of salinity stress on the biochemical reactions of almond genotypes, a factorialexperiment was carried out based on completely randomized design (CRD), with two factors; genotypesin 4 levels (Shahrood 12, ‘ Touno’ cultivars and ‘ 1-16’ genotype budded on GF677 rootstock and GF677(without budding)) and irrigation water salinity in 3 levels (0, 1. 2, 2. 4, 3. 6, and 4. 8 g/L of natural saltequal to electrical conductivity of 0. 5, 2. 5, 4. 9, 7. 3 and 9. 8 ds/m respectively). Total phenolics, antioxidant capacity, soluble carbohydrate, non-soluble carbohydrate, proline, total soluble proteins, hydrogen peroxide, malondialdehyde, other aldehydes, enzymes activity of catalase, ghayacol peroxidaseand ascorbat peroxidase were measured at the end of experiment. Results showed that in all genotypeswith increasing salinity level (to 4. 8 gr/lit), the content of hydrogen peroxide, malondialdehyde and otheraldehydes were increased. Also, the content of total phenolics, antioxidant capacity, solublecarbohydrates, proline, total soluble proteins, enzymes activity of catalase, ghayacol peroxidase andascorbat peroxidase, were increased at the lower salinity levels (1. 2 and 2. 4 g/lit), but their contents werereduced in higher salinity levels. Thoroughly, the highest content of soluble proteins, enzymes activity ofcatalase, ghayacol peroxidase and ascorbat peroxidase at salinity level 3. 6 gr/lit and the highest content oftotal phenolics, antioxidant capacity, soluble carbohydrate and prolin at salinity level 4. 8 gr/lit wereobserved in ‘ Shahrood 12’ cultivar. Also, the lowest content of hydrogen peroxide, malondialdehyde, other aldehydes and total non-soluble carbohydrate at salinity levels 3. 6 and 4. 8 gr/lit were observed in‘ Shahrood 12’ cultivar. Finally, ’ Shahrood 12’ budded on GF677 rootstock was recognized as the mosttolerant cultivar to salinity.

The present study aims at evaluating the impacts of harvest time and storage duration on fruit quality andstorage longevity of physalis (Physalis angulate L. ). As such, an experiment has been conducted in 2016, based on completely randomized design (CRD), having three iterations. The involved factors includedthree fruit harvest stages (mature green, yellowish green, and yellow) as well as storage time (0 (i. e., theharvest time), 10, 20, and 30 days). Results show that different harvest times and storage durations haveinfluenced fruit quality indices and storage longevity significantly, with the highest value of flavor andfruit color index, vitamin C (201. 54 mg), and total soluble solids (TSS) (7. 6% of brix) contents belongingto the fruits, harvested at the yellow stage with 10 days of storage duration, while longer storage durationsreduced vitamin C and TSS contents. The maximum titratable acidity (1. 71 mg/100gr) and pH of the fruithave been observed in the mature green stage and at the harvest time. The variations in fruit colordifferences in storage indicate an upward trend in the amount of mature green fruit, which differssignificantly from yellowish green and yellow fruit. According to the results, due to climactic nature ofphysalis fruits as well as their gradual ripening and fruit color change, harvesting the fruits at maturegreen stage increase the storage life up to 30 days at 15 ° C, compared to other fruits' harvest times.

Documentation in agricultural production involves giving all pieces of information as well as activitiesthat show the production route of a crop, ranging from providing the stage for sowing the seeds to harvestthe crop, itself. As a result, the present research recorded all these managing operations for local cultivarsof rice through field study in Mazandaran, Babol, between 2015 and 2016. Results show that from the155 variables under research, the final model with six independent variables has been chosen, in whichmaximum and average yields have been 6489 and 4572 kg ha-1, respectively, as compared to observedaverage and maximum yields (i. e., 4572 and 6489 kg ha-1). The entire estimated yield gap has beenequivalent to 1977 kg ha-1. The amount of yield increase from yield difference of two variables of the bestand average pest and weed problems has been equal to 7% and 3% of the total yield increase (i. e., 140and 59 kg ha-1), respectively. This increase is related to fallow variable, which has been 62 kg ha-1 or 3%of total yield increase. The quantity of yield increase is also related to the effect of Amrollahi cultivar, with plant density being 375 and 367 kg ha-1 respectively, equal to 19% of total yield variation. Moreover, the amount of yield increase is related to nitrogen consumption variable, before transplantingand after flowering stages, being equal to 355 and 619 kg ha-1, i. e., 18% and 31% of total yield increase, respectively. Therefore, based on this study's findings, it can be stated that the model precision has beenappropriate and applicable for not only evaluation of the amount of yield gap but also determining theportion of each restricting yield variable.

An experiment has been conducted to examine the effects of different tillage systems and fertilization onquantitative and qualitative characteristics of cumin as split plots, based on completely-randomized blockdesign with three replicates in Delfan in 2016. The main plots include three different tillage system: 1) conventional (mold board plough, chisel plough, and disk), 2) minimum tillage (chisel plough anddisk), and 3) zero tillage (disk), while the subplots comprise eight different combinations of organic andchemical fertilizer: 1) control, i. e., without any dose of manure and fertilizers, 2) 25 kg N ha-1, 3) 10 tonvermicompost ha-1, 4) 20 ton cow manure ha-1, 5) 20 ton municipal solid waste compost ha-1, 6) 50% doseof chemical fertilizer (N) + 50% vermicompost, 7) 50% dose of chemical fertilizer (N) + 50% cowmanure, and 8) 50% dose of chemical fertilizer (N) + 50% compost. Results show that the highest grainyield (81. 53 g/m-2) and biological yield (210. 41 g/m-2) have been achieved in minimum tillage and theapplication of cow manure, while the least quantities of these parameters have been observed in zerotillage and control. In addition, the greatest essential oil percentage and yield has been observed inminimum tillage and the application of 10-ton vermicompost, which was 25% and 28% greater thancontrol. Results suggest that in order to improve quantitative and qualitative characteristics ofcumin, it is recommended to apply manure and vermicompost, while having minimum tillage.

The present paper aims at examining the germination response of basil seeds (Ocimum basilicum L. ) totemperature and determining cardinal temperatures for percentage and rate of germination. For thispurpose, a combined experiment was performed from 2016 to 2017 at the seed technologylaboratory of Abu-Raihan Campus, Univerity of Tehran, through a completely-random designwith four replications and six thermal levels (8, 15, 20, 25, 30, and 35 degrees centigrade), thusenabling the evaluation of 22 Basil accessions that include “ Tehran” , Green Shahr-e-Rey” , “ Green Birjand” , “ Purple Birjand” , “ Green Shiraz” , “ Green Zabol” , “ Zahedan” , “ GreenZahedan” , “ Kermanshah” , “ Green Pishva” , “ Purple Pishva” , “ Green Malayer” , “ Khash” , “ Localgreen Tonekabon” , “ Green Isfahan II” , “ Purple Isfahan II” , “ Green Isfahan III” , “ Green IsfahanIV” , “ Green Mash’ had” , “ American green Napoltano” , “ Italian Genovese” , and “ Switzerland” . It has been seen that the optimal range of temperature for germination percentage andgermination rate was from 19. 10 to 27. 78 and from 20. 32 to 29. 89 degrees centigrade, respectively, with the highest germination rate observed at 25 degrees centigrade in mostaccessions. Among all evaluated accessions in the current research, Isfahan III presented thehighest germination rate in all temperatures. Results from this experiment show that theresponse of germination percentage and germination rate to temperature is well described viaBeta Function and Segmented Function, respectively, and that the cardinal temperatures can bedetermined for Basil by means of these two models.

Non-Chilling Peel Pitting (NCPP) is a physiological post-harvest and storage disorder, in many citruspeels. The purpose of this study, was to determine the effects of the steroidal plant hormone, 24-epibrassinolide (0, 5 and 10 mg L-1) and relative humidity at the dry storage (RH=30% and 20 º C)compared with normal (RH=70% and 6 º C), on the shelf life of Thomson-Novel sweet orange. Theexperiment was performed as a factorial arrangement in Completely Randomized Design (CRD) duringwinter of 2015in 30 days with three replicates and 10 samples. In this Research characteristics of fruitsuch as weight loss, NCPP, open stomata, total soluble solids, titrable acid, leakage, Catalase andMalondialdehyde activity investigated. The results indicated that weight loss (9. 67%), NCPP (33. 3%code) and Catalase activity (0. 13682) in fruits peel significantly increased under drough stress. Maintenance of fruits in dry environments causes a reduction in the open stomata of skin from 55. 3 to36. 1%, which improved using 24-epibrassinolide, as well in normal storage (51. 1%). According to theresults, 5 mg L-1 24-epibrassinolide concentration was recommended considering its reduction effects onweight loss rate, NCPP and Catalase activity in fruits skin.

In order to study the effect of green manure and different levels of nitrogen on nitrogen yield and useefficiency in purslane, an experiment has been conducted at the Research Farm of Birjand University as asplit plot design, based on completely-randomized block designs with three replications for the timeperiod between 2014 and 2015. Four green manure varieties (control (i. e., no green manure), Vicia villosaL., Eruca sativa L., and a mixture of both) as well as three levels of nitrogen (viz. 0 (control), 50, and 100kg. ha-1) have been considered as main plots and sub plots, respectively. Results show that the use ofgreen manure has had no effect on grain and forage yields of purslane. The use of 100 kg. ha-1 nitrogenhas also led to an 18. 81% increase in dry forage yield (3992. 3 kg. ha-1), in comparison with the control(3360. 1 kg. ha-1). In addition, it has been shown that green manure with high nitrogen levels improves theyield and nitrogen content of biomass, reducing absorption and agronomy efficiency of nitrogen, based onforage yield. Results reveal that given the reduction of nitrogen efficiency, despite the use of green andnitrogen fertilizers, as well as the production costs and environmental problems, nitrogen amounts of 54. 6kg. ha-1 and 50 kg. ha-1 in the soil will suffice for sustainable production of grain and forage production ofpurslane, respectively, while any higher consumption of nitrogen will be a luxurious aspect.

An experiment has been conducted with the aim of investigating the effect of polyamines on vegetativeand biochemical traits of Crocus sativus L. It has been in the form of a factorial in a completelyrandomizedblocks with three replications during 2015-2016 and has taken place in field research ofTarbiat Modares University. There has been three sizes of corms (i. e., 3-5, 5-7, and 7-10 g) as well as fiveconcentrations of polyamines (zero in control, zero in distilled water, spermidine 0. 5 and 1 mM, andputrescine 0. 5 and 1 mM) as the treatments. Results show that the plants, treated with putrescine 0. 5and spermidine 1 mM, have had the highest germination percentage (96. 56%) as well as the highestnumber of lateral sprouts (with an average of 8. 33 sprouts), respectively. It has also been revealed that thelength and weight of the leaves are negatively affected by polyamine treatment. The highest chlorophyllcontent and corm yield are observed in the plants, treated with Putrescine 0. 5 mM and 1 mM, respectively. The content of starch and soluble carbohydrates in dormant corms at the end of growingseason have not been affected by polyamines significantly; however, total phenolic and flavonoid contentin these corms have decreased and increased, respectively, as a result of applying polyamines. With nosignificant effect on stigma dry weight and picrocrocin content, polyamine treatment has increased thenumber of flowers and crocin content in small corms. It can be concluded that in order to obtain bettervegetative and biochemical traits of saffron, corms more than 7 g and treated with putrescine, should beused.

In order to evaluate the effects of seed priming to reduce water deficit stress in safflower cultivars, anexperiment was conducted as a split-plot factorial based on randomized complete block design with threereplications at Shahrood Agricultural Research Center in 2015. The main plot consisted of irrigation atthree levels based on the evaporation from class A evaporation pan: non-water deficit stress (60 mmevaporation), mild water deficit stress (120 mm evaporation) and severe water deficit stress (180 mmevaporation) and subplots consisted of two factors include safflower cultivars (Goldasht, Sina, andSoffeh) and seed priming (Primed seeds with salicylic acid and non-primed). The results showed thatsevere water stress reduced the grain yield by about 29 percent compared to non-stress conditions. Inthese conditions activity of superoxide dismutase, peroxidase, ascorbate peroxidase, and catalase enzymeswere increased by about 33, 25, 29 and 40 percent respectively. In severe water deficit condition, thecontent of malondialdehyde, proline, and carotenoid significantly increased, but the amount ofchlorophyll was reduced. Priming of seeds with salicylic acid caused to increase the antioxidant defensesystem activity by about 7-9 percent, therefore increased the resistance of safflower plants to water stressand resulted in greater seed yield under water stress conditions. Interaction of irrigation and cultivarappeared to be significant on seed yield and activity of catalase peroxidase, and ascorbate peroxidaseenzymes.

The present research has been conducted to investigate the effect of potassium Nano-fertilizer on soybeangrowth, irrigated with holding condition. To do so, an experiment has been carried out with split plotsarrangement, based on completely-randomized block design with three replications in Mugan Plainduring cropping seasons of 2015 and 2016. The main factor has been four levels of irrigation (IR), namely normal irrigation, cutting irrigation during vegetative phase, cutting irrigation during floweringphase, and cutting irrigation during grain filling phase, with the sub-factor being three levels of 5, 10 and15 kg. ha-1 for potassium Nano-fertilizer (NK). Results show that the use of potassium Nano-fertilizerhave reduced the effect of drought stress at all stages of irrigation; therefore, no wonder that the greatestseed yield and yield components under normal irrigation and off-irrigation conditions have been obtainedfrom the use of 15 kg. ha-1 potassium Nano-fertilizer. Also, the highest plant height (66 cm), the distancebetween the first pod of ground (20 cm), number of leaves per plant (345), and the number of lateralbranches (19. 66) have been obtained at the normal irrigation treatment in which the consumption ofpotassium Nano-fertilizer is 15 kg, and the lowest values of those treatments have been obtained at theirrigation cut, during vegetative phase that uses 5 kg. ha-1 of potassium Nano-fertilizer. In addition, oilpercentage and seed protein have been strongly affected by drought stress, especially cutting irrigation atthe grain filling phase. According to the results, it can be concluded that 15 kg. ha-1 of potassium Nanofertilizerapplication can reduce the effects of drought stress on yield (by 15%), especially at the seedfillingstage of soybean.

In highly stressed ecosystems, symbiosis between plants and has beneficial effects onplant growth. Theobjective of this study was the effects of two dark septate endophyt fungi againstmycorrhizal (Glomusmussea and Glomus interaradices) and Piriformospora indica on spinach growthin without and withdrough stress (Field Capacity (FC) and 50% FC). This study was done in the research greenhouse at Bu-Ali Sina University of Hamedan (2015-2016). The percentage of root colonization, wet and dry weights, contents of chlorophyll and some of the micro-and macronutrients have been analyzed in some adulttreated plants after six weeks. The colonization results showed that all studied fungi can effectivelyenterinto spinach roots. Inoculation with Glomus mussea increased the wet weight (20 g/plant) of the plants. Also, some morphophysiological and physological properties such as dry weight (4. 1 g/plant), chlorophyll content (2. 7 mg/g dry matter) and potassium to sodium ratio (8. 4) was increased when plantsinoculated with Curvularia specifera. However, high phosphorus content (311. 2 mg/100g dry matter)measured in plants that was inoculated with Glomus interaradices. Generally, this study showed that darkseptate endophyte could be benefical in grwoth of spinach as much as mycorrhizal and Piriformosporaindicasymbiosis.

This experiment was performed to evaluate the effect of nitrogen source type and plant growth promotingbacteria on yield and its attributes of Talesh local garlic as split plot arrangement based on randomizedcomplete block design with three replications in experimental field of Guilan Agricultural and NaturalResources Research and Education Center (Rasht) Iran, during the 2016-2017 cropping season. Threenitrogen sources of vermicompost (15 ton/ha), nitrogen (100 kg /ha), integrated utility of vermicompost(7. 5 ton/ha) with nitrogen (50 kg /ha) as main plot and ten preparation of plant growth promotingincluding of non-inoculation (as check), Azospirillum brasilense, Azospirillum lipoferum, Pseudomonasputida, Pseudomonas fluorescens, Azotobacter, Azospirillum + Pseudomonas, Azospirillum + Azotobacter, Pseudomonas + Azotobacter, Azospirillum + Pseudomonas + Azotobacter as sub plot comprised experimentaltreatments. The greatest bulb yield was obtained under the usage of 100 kg nitrogen per hectare as ureafertilizer and simultaneous application of Pseudomonas and Azospirillum spp. There was a positive andsignificant correlation between bulb yield and all traits such as biological yield, bulb diameter, bulb height, clove numbers per bulb, clove weight, dry weight of bulb, dry weight of stem, leaf numbers per plant and plantheight except bulb shell layers. Also, the correlation between yield attributes such as clove numbers per bulb, clove weight, bulb diameter, bulb height and vegetative characteristics of bulb plant was positive andsignificant. In general, bulb yield and its attributes showed different responses to nitrogen sources and plantgrowth promoting bacteria. Based on results of this experiment, the application of Azospirillum +Pseudomonas could be recommendable to improve bulb yield of garlic in conventional agriculture and underregion climatic condition.

In order to evaluate the effect of water deficit stress on seed yield and yield components of safflowergenotypes (Carthamus tinctorius L. ), an experiment has been conducted as a split plot with threereplicates at the research filed of University of Shahrekord for the duration of spring 2016. The treatmentshave consisted of three levels of irrigation based on 100%, 75%, and 50% of the plant’ s waterrequirement as well as three selected safflower genotypes, including Sina, Isfahan, and Faraman. Resultsindicate that deficit irrigation causes a significant reduction in all traits, namely the number of lateralbranches per plant, plant height, number of heads per plant, number of seeds per head, the weight of seedsin thousand, seeds' yield, oil percentage, oil yield, biological yield, and harvest index. The lowest valuesof seed yield (1196 kg. ha-1) and oil yield (313 kg. ha-1) are for the deficit irrigation treatment of 50% ofplant's water requirement, while the highest seed yield (2310 kg. ha-1) and oil yield (561kg. ha-1) have beenobtained in 100% of plant's water requirement. Also, according to the obtained results, it can be seen thatthere has been a significant variation among investigated safflower genotypes, wherein the highest seedyield (1998kg. ha-1) and oil yield (561kg. ha-1) belong to Sina genotype, whereas the lowest seed yield(1659kg. ha-1) and oil yield (426 kg. ha-1) are related to the local Isfahan genotype. Accordingly, it can beunderstood that the variations among genotypes in terms of morphological traits, oil percentage, and oilyield are important components that could be used to select genotypes or appropriate cultivars withdrought conditions.

To study the factors affecting soybean yield loss, an experiment was conducted in the Kalaleh region atsummer of 2016. The sampling of weeds was taken in the early growing season based on W pattern in 50fields. In this study, all agronomic management information including land area, farmers’ experience, seedbed preparation, sowing date, cultivar and provided seed sources, sowing methods, seed rate, weedscontrol methods, amount and time of herbicide application were collected during growing season bypreparing the questionnaire and complete them with farmers. Soybean grain yield determined at the endof the growing season. Asian spider flower (Cleome viscosa L. ) and Johnson grass (Sorghum halepense L. )had significant effects on soybean yield among the various parameters of the field area, seed rate, certified seed application and planting date. The predicted minimum and optimum yields with the modelwere 1039 and 2036 kg. ha-1, respectively. Thus, yield gap between predicted minimum and optimumyield was estimated at 996 kg. ha-1 in this region. Results showed that certified seed (23. 07 percent), delayed planting date (15. 04 percent), low seed rate (11. 54 percent), low field area (7. 62 percent), presentof Johnson grass and Asian spider flower weeds (12. 47 and 30. 25 percent, respectively) were the mosteffective factors on soybean yield gap. Thus, optimizing mentioned factors can be reduced yield gap.