PLANT ECOPHYSIOLOGY (ARSANJAN BRANCH)
Year:2013 | Volume:5 | Issue:12|Papers Count:9

In order to investigate the effect of salicylic acid as a salinity reverse effects retardant, an outdoor pot investigation was carried out in Islamic Azad University, Eghlid branch from Nov. 2010 to May 2011. The experiment was conducted as triple factorial based on complete randomized design with three replications. The first factor comprised of two salinity levels (non-saline irrigation water [EC=0] and saline irrigation water [EC=10ds/m]) and the second one consisted of two morphologically similar wheat cultivars, Dena as durum and Shiraz as bread type, and the third factor was application or not the salicylic acid solute. The salt treatments were accomplished four weeks after seed sprouting. The salicylic acid treatments were applied a week prior to salinity application i.e. 3-4 leaf stage. The measured parameters were biological (BY) and grain yields (GY), photosynthetic parameters, chlorophyll content, relative water (RWC) and protein content. The results showed that salicylic acid application caused GY, BY, RWC, Chlorophyll and photosynthesis to increase, but it remained ineffective on protein content. Salinity caused reduction in BY, GY, RWC and photosynthesis, but increased protein and chlorophyll content. Bread cultivar showed higher GY amounts than durum one. Durum's GY was more susceptible to salinity than bread's. SA was more effective in durum wheat than in bread type. SA also had different effects under various salinity levels. It was more effective under lower levels of salinity. Generally the highest and the lowest GY amounts were respectively seen in bread wheat under nonsline condition and with application of 0.5 mm SA, and in durum wheat under salinity without SA application.

This study aimed at determining the rate of tolerance to welter in conditions of none water using experimental epilate stripe plan including welter sensivity, tolerance and stress tolerance indices, (GMP), (MP) with three replicates in 2011-2012 in Damghan city. Result shows that with been types proud action grain variation was significant (P<0.05). In condition without stress Types 33 with 4790 kg. Ha had maximum production and also in stress condition type 33 with been 2645 hg had maximum production and maximum Index rate (STI) was in top stress depended type. Type 33 shows Maximum (MPL) (GMP) and the correlation of index with production in normal condition and stress condition shows that production in stress condition YS significantly correlated with (YP) and Index. Totally except sensitivity index in (SSI) and correlation (YP) With STI,MP,GMP, TOL significant correlation was found between MP with STI and GMP, and also STI with GMP. But maximum correlation was found between MP and GMP. SSI Shows no significant correlation with all indices. The result showed that the STI. MP, GMP, Indices were appropriate for estimating production.

In order to study the effect of drought stress and salicylic acid on parameters of physiology (membrane stability index ) and biochemical (photosynthetis pigments) an experiment was conducted under four drought levels, based on Field Capacity (100% FC, 75% FC, 50% FC, 25% FC) and treatment of Salicylic acid (0 , 0.7 mM) using a completely randomized design with three replications. The results showed increasing drought levels significantly decreased all parameters except chlorophyll a/b ratio in two genotypes. Application of salicylic acid (0.7 Mm) significantly increased membrane stability index and carotenoids in MCC358 genotype and also increased chlorophyll b and total chlorophyll content in MCC441 genotype. It seems that inhibitory effect of drought stress in MCC441 genotype was more effective than MCC358 genotype. Also, Application of salicylic acid could not improve growth parameters in MCC441 genotype.

To study the drought tolerance of different cultivars of sunflower (Helianthus annuus L.), an experiment was conducted in factorial experiment based on a completely randomized design with three replications. Two sunflower cultivars named Euroflour and Hysun 33 were used as the main factor and different levels of drought stress (FC, -0.3, -0.6 and -0.9 MPa) and foliar application of salicylic acid (0 as control and 100 mM) as the sub factors. Results indicate that by increasing drought level, leaves macronutrients and photosynthesis pigments in both cultivars increased significantly. Maximum rate of decreasing in above parameters observed in -0.9 MPa level. Results show that Hysun33 cultivar is more drought resistance than Euoroflour. Foliar application of salicylic acid in 100 mM concentration has also significantly increased all parameters of both sunflower cultivars under drought stress.

To evaluate the effects of glycine betaine (GB) on yield and yield components of sunflower (Helianthus annuus L.) in saline condition, a field experiment was conducted in Islamic Azad University, Sabzevar Branch, in 2011. The experiment was carried out in factorial arrangement on the basis of a randomized complete block design with 3 replications. Factors were time of GB application at 3 stages (V5 (5 leaves), R1 (forming of terminal bud) and R5 (beginning of flowering) and 4 GB rates (0, 50,100 and 150 mM).The results showed that foliar application of GB at V3 had the highest economic yield, biological yield and grain number in capitul. Delay in GB application increased potassium level in leaf. 100 seed weight was not affected by GB time application, although V5 had the highest 100 seed weight. Increase in GB rate increased linearly yield and yield components. 150 mM foliar application of GB had maximum yield and yield components. There was no significant difference between 100 and 150 mM foliar applications of GB. Na content increased 5.75% by increasing GB from 100 to 150 mM. Overall in saline conditions, 100 mM foliar application of GB at V5 was found to be the best treatment for achievement of maximum grain yield.

In order to investigate the effects of manure and application of Nitroxin fertilizer accompanied by gibberellin on corn (Zea mays L.) in Baiza (Fars province), a split factorial experiment arranged in randomized complete block design (RCBD) was conducted with three replications. Treatments included manure (zero and 30 t ha-1) and Nitroxin fertilize (zero and 35 g a.i/ha-1) respectively, each at two levels as main plots and three levels of gibberellin (zero, 100 and 200 ppm) as sub-plots. Results showed that the effect of their interaction was not significant on many traits and characteristics but significant for single effect. The highest traits related to application of different levels of manure obtained in treatment of 30 t of manure per hectare. The results showed that Nitroxin fertilizer application of 35 g/ha-1 increased many traits. Gibberellin increased the traits but among the levels of between 100 and 200 ppm no significant difference was observed some traits. The highest grain yield was obtained in treatment of 30 t/ha-1 of manure, Nitroxin fertilizer the rate of 35 g/ha-1 plus 100 ppm gibberellin. Results showed that in the current conditions and considerhng the development of sustainable agriculture, use of these inputs can be beneficial and justified.

Nitrogen is necessary for plants growth. Symbiotic N2-fixation is the most important source of nitrogen in legumes. A filed study was conducted to evaluate 10 rhizobium strains (l-78, l-195, l-192, l-54, l-75, l-30, l-100, l-197. l-120 and l-177) and two nitrogen fertilizers treatments (35 and 75 ppm N) with control treatment (without inoculation and N2 – fertilizer) in yield of bean in 2009-2010. Experimental design was randomized complete block (RCBD) with four replicates. The weight of dry mater, nitrogen in leaf and seed and yield of bean were calculated. In the first year, the results indicated that there was a significant difference (at 5 %) in grain yield between treatments. The best seed yield and nitrogen in dry mater were obtained in L-54 strain treatment. This yield inceased 174 % compared with control treatments. In the second year, the results showed that there was a significant difference between treatments (at 5 %). The maximum yield was obtained by L-77 and L-54 strains with 1595 and 1511 kg/ha respectively. The yields of this treatment increased 41 and 33 % compared with control treatment (without inoculate and nitrogen fertilizer). Based on the results in two years of experiment we showed that the highest yield and protein were obtained by rhizobium inoculated of bean.

In order to investigate the effects of nitrogen and weeds interference (Amaranthus retroflexus L. and Chenopodium album) on millet yield and yield components, an experiment was done in a greenhouse in Bavanat region, Fars province, in atumn 2010. The experimental design was completely randomized with a factorial treatment arrangements replicated three times. The first factor, was the rate of nitrogen from urea source including; 0, 100, 200 kg nitrogen per ha and the second factor was the competition of millet and weeds in 3 levels including a pure millet without weeds and 2 levels of millet and weeds intercropping (pigweed and lamsquarter). Measured traits were grain yield, biological yield, harvest index and plant relative yield (PRY). The results showed that the effects of weeds interference on millet yield and yield components were significant. The increase in nitrogen level from 100 kg/ ha to 200 kg did not noticeably affect millet yield because of the high weeds competition; the increase of nitrogen decreased milled yield. The effect of various nitrogen levels and various weed treatments and their effects on grain yield, biological yield and the harvest index of millet were significant. The PRY index decreased with the increase in weed density. In the mixed culture of millet and lambsquarter, PRY in lambsquarter was lower than that of millet and in the mix of millet and pigweed the amount of PRY was higher than that of pigweed. It may indicate that pigweed competed severely with millet.