JOURNAL OF CROP PRODUCTION RESEARCH (ENVIRONMENTAL STRESSES IN PLANT SCIENCES)
Year:2011 | Volume:3 | Issue:2|Papers Count:9

To evaluate the drought tolerance indices in sunflower cultivars an experiment was conducted in split plot design based on randomized complete block design with three replications at two levels (Drought stress and non-stress condition) for 8 cultivars of sunflower in farm research of Islamic Azad University, Tabriz branch, during 2008 planting season. Based on yield under non stress condition (YP) and stress (YS), quantitative indices of drought tolerance, such as: tolerance index (TOL), geometric mean productivity (GMP), harmonic mean (MH), stress susceptibility index (SSI ) and stress tolerance index (STI) were calculated. In both conditions the highest grain yield and the highest GMP, MH and STI were for “Ghalami” cultivar. Simple Pearson correlation coefficient between above indices and average yield of seed and oil in stress and non drought stress conditions showed, TOL index with oil yield and STI, GMP indices with seed yield had positive significant correlation in both stress and non stress conditions. Therefore, STI, GMP were sujested according to seed yield and TOL was recommended in the basis of oil yield for tolerant cultivars selection respectively. Based on the above superior indicators, Pen and Haysan 33 cultivars identified as the most tolerant cultivars in the basis of seed and oil yield characters alternatively.

In order to evaluate the effect of amount and period of methanol foliar methanol application on Qualitative and quantitative traits of sugar beet, an experiment was conducted as split plots in the basis of complete randomized blocks design in 3 replications in 2010 at Karaj research field. Periods of methanol foliar application (every 10 days and every 20 days) were as main-plate and methanol solution concentration in 3 levels (0 (control), 14 and 28 %( v/v)) were considered as sub-plot, that each solution contained 2gr/lit glycine. There weren't significant differences between simple effects of foliar methanol period application and interaction effects of periods of foliar application and methanol solution amounts on all of measured traits. Analysis of variance indicated that there were significant differences between aqueous methanol solution on root yield, sugar yield and white sugar yield. The results indicated that, solution of 14% and 28% of methanol had the most root yield with 85.02 and 83.43 ton/ha arrange mentally. There were not significant difference between these treatments and control with 66.28 ton/ha which had the least root yield.

In order to evaluate the effect of Azolla compost and irrigation on yield, yield components and growth performance of rice varieties Hashemi, an experiment was carried out in Rice Research Institute of Iran (Rasht) during 2009. The experiment was arranged in a randomized complete block design as split-plot with three replications. In this experiment, three irrigation management (I1=100% control and I2, I3, respectively, irrigation with 80%, 60% evaporation from a class A evaporation pan) as the main plot and different amounts of composted azolla at 4 level (C1 C2, C3 and C4, respectively, without the use of compost, 4 tons, 8 tons and 12ton/ha) respectively as sub plots. The results showed that reducing the amount of irrigation water in the evaporation of 60%of pan evaporation, Harvest index, and total biomass and grain yield increased significantly. The effect of different amounts of compost and harvest index, total biomass and grain yield, was significant. Maximum grain yield of rice gained in irrigation with 60% evaporation from evaporation pan and 8 tons/ha Azolla compost application. Maximum total dry matter accumulation was calculated in irrigation after 60% evaporation and 8 ton/ha of Azolla consumption. Maximum leaf area index (LAI) was achieved in irrigation according to 60% evaporation and 8 tons/ha compost using.

Now a days, there is a great tendency of the sustainable and low-input agricultural system based on economic and ecological reasons. Nitrogen (N) is of the main input on wheat in high-input in this systems that pollutes soil and Underground water. Therefore, availability of varieties to high N uptake efficiency and N utilization efficiency is very important. This research was conducted with 20 wheat cultivars in a clay-loam soil with 2 N level (0 and 200 kg ha-1) in a RCB design with three replications in 2007-08 plant season. The results showed, high reaction and diversity to N reducing in genotypes in most characters. There were significant differences in genotypes. Evaluation of G´N interactions showed significant differences for thousand kernel weight, grain N concentration, stable N concentration, N uptake efficiency and N use efficiency at p=1% and number of seed per spike at p<5%. The result of comparison of means trials wrer showed that Koohdasht, Chamran and Gobustan cultivars at both N levels had high grain yield, but Zagros, Talee-38 and Gunashli had high grain yield at N0 and low at N+. Also, the experiment showed high diversity for N uptake efficiency and NUE for all N levels, G and GxN interaction. Mean comparision showed cultivars Gobustan, Talee-38, Zagross and Koohdasht the highest N uptake efficiency ones. For NUE cultivars Gunashli, Talee-38 and Darya were the best at two N levels. The cultivar of Nurlu-99 showed the highest sustainable to N reduction. In this study based on grain yield, N uptake efficiency and NUE, Gobustan, Koohdasht and Chamran purpose for breeding as the best cultivars.

This research was carried out for investigation the effect of different sowing dates on panicle characteristics and yield of rice cultivars in Shavoor Agricultural Research Station in Khuzestan. It was performed as split-plot design on the basis of randomized complete block design with 3 replications. The main plots were planting dates in 3 levels (15 March, 14 April and 26 May) and the subplots were including 10 genotypes (Dollar, N22, Gerde zanjan; 3 local cultivars: Hoviezeh, Gerde Ramhormoz and Hamar, 2 foreign cultivars: CR547-1-2-3 and IR1567-228-3-3; and 2 lines: 7 and 13).Results showed that the highest yield, number of full seeds and fertility percentage were related to Hoveizeh and Hamar cultivars in third planting date. The line 7 had the highest 1000-grain weight. Panicle numbers in m2, primary and secondary branch, panicle weight were recorded in 3rd sowing date but panicle lengthand the number of seeds per panicle had the highest amount in 2nd planting date. In according to results; foreign cultivar of IR1567-228-3-3is recommended for 15 March sowing (had the highest harvest index in all planting dates) Hoviezeh and Hamar are recommended for other planting dates.

In order to study the effect of limited irrigation on photosynthesis, CO2 exchange and seed yield in four cultivars of sunflower (Helianthus annuus L.), a field experiment was conducted in the basis of split plot using randomized complete blocks design with three replications in Zanjan Agricultural Research Center in 2009 cropping season. Limited irrigation levels included: normal irrigation, Stop irrigation in flowering stage, Stop irrigation in grain filling stage that arranged in main plotsand, sub plots were the cultivars in four levels: Master, Lakomka, Euroflour and Azargol. Limited irrigation had significant effect on grain yield and physiological traits. The highest seed yield obtained from Azargol cultivar in normal condition. Stop irrigation at the beginning of flowering stage (Anthodium formation), caused the highest grain yield reduction, so that Master, Lakomka, Azargol and Euoroflour cultivars, showed %62, %52, %65 and %63 seed yield reduction respectively. Water stress had significantly effect on physiological traits too. Drought stress in different stages, reduced photosynthesis rate in all of four cultivars. In flowering stage stop irrigation (Anthodium formation); photosynthesis rate reduced 26%, 27%, 20% and 30% for Master, Lakomka, Azargol and Euoroflour cultivars respectively. In flowering stage stress, photosynthesis rate reduced 42%, 24%, 22% and 39% for Master, Lakomka, Azargol and Euoroflour cultivars and in grain filling stage drought stress, reduced photosynthesis rate 34%, 22%, 16% and 25% for Master, Lakomka, Azargol and Euoroflour cultivars alternatively. In all of three irrigation levels, drought stress decreased stomata conductivity in all cultivars and in sub stomata CO2 exchange, in drought stress condition, Azargol cultivar had the best yield and photosynthesis characters compare with the other cultivars.

To examine the effect of delay cropping dates in different genotypes of silage corn genotypes as a second product, an experiment was conducted at Mazandaran Agricultural Research center based in Ghaemshahr (Gharakheil) in crop year 1389, as splip plot in the basis of randomized complete blocks design in 4 replications. Planting dates in 4 levels (23july, 1Aug, 12 Aug and 22 Aug) were as main factor and 3 corn genotypes (Early maturing S.C540, mide maturing S.C647 and late Maturing S.c704) considered as sub- factors. The Results indicated that the maximum and minimum amounts of leaf dry weight and corn yield respectively achived on 23 july and 1 Aug. Maximum ratio of corn dry weight achived on23 july and 1Augrespectively. The plant height with delay in plantation decreasing trend 21.3% in silk worm stage. The Forage dry weight decreased 33.6% after delay in plantining time. The most leaf and corn dry weights and maximum forage dry yield achived for early maturing genotype (S.C540). The plant height were minimum and the corn dry ratiotototal dry weight were lowest in silk stage for late maturing S.C647. The maximum corn dry weight affected by interaction effect of genotype and planting date for early maturing genotype and 1Aug. The highest plant height in silk formation stage for early maturing genotype (S.C540) gained in planting on 1Aug plantation and for late maturing hybrid(S.C704) conducted on 23 july. For delay cropping of summery silage corn in Mazandaran province, early maturing genotype (S.c540) and planting on 23 july1Aug is recommended.

In order to study the integrated effect of nitrogenand organic fertilizer on yield and yield components of Tarom cultivar of rice a field experiment was carried out at the Haraz Technology Development and Extension Center in Mazandaran (Amol) during 2010. The experiment conducted as a randomized complete block design with 8 treatments and 3 replications. Treatments included two kinds of organic fertilizer (Bioll555) and Azola compost that every one of those was incorporated whit amount of nitrogen as: 1- without nitrogen 2- whit 50% N at basal 3- with 50% N (25% at basal and 25% at panicle initiation) and 4- with 100% N (50% at basal, 25% at tillering stage and 25% at panicle initiation). Other cultural practices were down to all plots according SRI method monotonously. In this study, plant height, panicle length, tillers and panicle number per hill, filled grains and total grains number per panicle, 1000 grain weight, economical and biological yield and harvest index were measured. Results showed that were not significant differences for grain yield among treatments, nevertheless the highest grain yield (4.491 t/ha) belonged to T8 (organic fertilizer Bioll555+100% Nitrogen (50% at basal+25% at tillering stage+25% at panicle initiation) and the lowest grain yield (3.673 t/ha) belonged to T1 (Azola compost without N application) which indicate N is very important in rice production. For all measured traits, organic fertilizer (Bioll555) had superiority in comparison with Azola compost. We found that organic fertilizer is advantageous for decrease of N application up to 50%.