نشریه علوم به زراعی گیاهی
سال هفتم شماره 2 (پاییز و زمستان 1396)

In order to evaluation of trend yield and physiological indices variation of some current Rice cultivars an experiment was carried out in split-plot arrangement using randomized complete blocks design with three replication. In 2006 and 2007 years at Shavoor Agricultural Research Station in Khuzestan province. For exposing rice cultivars to different higher temperature regimes, main plots were assigned to three sowing dates from 5 May with 20 days intervals and cultivars namely: Hoveizeh, Hamar (heat tolerance) Ghermez Anbori, Champa (heat sensitive) and Danial (relatively heat tolerant) were randomized in sub-plots. The results of combined analysis of variance showed that the highest grain yield was harvested from the second sowing date (26 May). It was the superior to first sowing date (5May) with 62.5 percentages. The reason of higher yield related to superior physiological indices in panicle exertion, LAD in ripening duration and also higher dry matter storage potential. In among cultivars, Hoveizeh was the superior to other cultivars and had higher yield related to Ghermez Anbori, Champa with 50.9 and 36.3 percentage respectively. In spite of heat sensitive cultivars had higher of Maximum leaf area index but their's crop growth rate, net assimilation rate and relative growth rate were lower.

This experiment was conducted as factorial based on completely randomized blocks design with 3 replications during 2014-2015 in Ramhormoz, Khozestan province. The experiment consisted of two factors: nitrogen fertilizer rates: (zero, 50, 100 and 200 kg per hectare) and split nitrogen application included: T1 = (50% at planting + 50% at stem elongation), T2 = (33% at planting + 33% at stem elongation + 33% before ear emergence), T3 = (25% at planting + 50% + 25%at stem elongation before ear emergence) and T4 = (25% at planting + 25% + 25% at stem elongation before ear emergence + 25% in the milky stage. The results showed that difference between the levels of nitrogen fertilizer in plant height, number of spikes per square meter, grain number per spike, 1000-seed weight, grain yield, biological yield, harvest index and the amount and efficiency of current photosynthesis at 1% level of probability and remobilization rate of dry matter at 5% level of probability. Effect of split application of nitrogen on plant height, number of spikes per square meter, grain yield, biological yield and current photosynthesis at 1% level of probability and the efficiency photosynthesis current at 5% level of probability was significant. The interaction of the amount and nitrogen fertilizer splitting on biological yield and efficiency of dry matter remobilization and efficiency of current photosynthesis at 1% level of probability was significant. The highest grain yield was in N2 (100 kg ha nitrogen) with 5.5141 kg/ha and fertilizer splitting in T3 (25% at planting + 50% + 25% at stem elongation before ear emergence) 4.4592 kg/ha, respectively. The greatest amount and efficiency of current photosynthesis were observed in N2 (100 kg/ha nitrogen) and T3 (25% planting + 50% + 25% stem elongation before Ear emergence). In general, consuming 100 kg/ha of nitrogen fertilizer with T3 splitting (25% planting + 50% stem elongation + 25% before Ear emergence) increase yield and yield components compared to other treatments and it can be recommended in the region of study.

In order to investigate the effect of growth promoting bacteria and potassium sulfate fertilizer on quantitative and qualitative characteristics of corn an experiment based on randomized complete block design with three replications was conducted in summer 2015 in Shavour Agricultural Research Station, affiliated to the Agricultural and Natural Resources Research Center of Khuzestan. The treatments included: T1: Without inoculation and use of potassium fertilizer at recommended rate (as control), T2: using autoclaved inoculum and using chemical fertilizer of potassium as recommended, T3: inoculation with biological fertilizer of Pseudomonas and application of potassium fertilizer to Recommended rate, T4: Inoculation with biological fertilizer of Pseudomonas without the use of potassium fertilizer and T5: Inoculation with biological fertilizer of Pseudomonas and Potassium fertilizer use were 50% less than recommended rate.  The results showed that the effect of treatments on the number of rows per ear, number of seeds per row, 1000 grain weight, grain yield, biological yield, starch percentage and potassium percentage of seed and in regard to phosphorus percentage was  not significant. The maximum grain yield and biological yield was belonged to T3 treatment. T4 treatment showed the minimum grain yield and biological yield. There was no significant difference between two treatments of T3 and T5 in terms of starch percentage. The highest amount of potassium was obtained from T3 treatment and showed the lowest amount of T4 treatment. In general, there was no significant difference between T3 and T5 treatments in terms of quantitative and qualitative characteristics of yield and the T5 treatment was recommended as a suitable treatment due to reduced potassium fertilizer in terms of sustainable agriculture and reduction of environmental pollution.

Water deficit is a common and major constrain for agricultural production in arid and semi-arid parts of the world like Iran, to the extent that it might threaten the nation’s food security in years to come. Seed germination is a crucial growth stage that is often affected by environmental stresses, including drought. This study investigated the effects of four levels of water osmotic potential (i.e. 0, -3, -6 and -9 bar) on germination and seedling characteristics, of three maize hybrids )SC500, SC640 and SC704). According to the results, different levels of drought stress, type of cultivar and intraction beatween them had significant effect on measured characteristics. Results also showed that significant decrease was observed in the percentage and rate of germination, radicule and plumule of long and weight and seedling total dry matter. SC500 as a drought-tolerant hybrid, indicated the greatest germination percentage radicle and plumule length, radicle and plumule dry weight than the other cultivars. So, this hybrid was more tolerance to water stress.

This study was aimed to evaluate the effect of planting method on the morphological and anatomical properties of Iranian alliums native populations. The experiment was conducted in spilt plot base on randomized complete block design with three repetitions for one year in Khuzestan. Main factor was at two levels (1: stream and ridges and 2: plot) and the secondary factor included two alliums masses of Shadegan and Ahwaz19. Results showed that on-ridges planting, in terms of better input management, in spite of having the minimum number of plant per square meter, had the higher level of agriculture properties such as more leaf per plant, length, width, and weight. Maximum stomata diameter and surface was achieved from plot planting, which increased the resulted-from–the yield quality reduction transpiration and dehydration in this method of planting, while the maximum number of stomates, because of the optimal conditions, was gained through the on- stream and ridge planting in Ahwaz19, and can be the main reason of the increase of the leaf’s dry weight. Based on these results, it seems that by concentrating the modifying goals on the mentioned anatomical properties, with the appropriate method of planting, we can hopefully expect an increase in yield resulted from the increase of pure photosynthesis.

For evaluating the operation of two systems of planting wheat in raised bed planting with furrow irrigation in comparison with conventional planting with Flooding irrigation a testing was conducted in year of 2017-18 in Shoushtar township located in north of Khuzestan province. The attendees were conducted which induced type of planting (wet planting, dry planting), planting with line adopting on the mound (fixed furrow-spring furrow) and 3 line of planting on the mound with spaces of 60 and 75 cm in 3 line in the furrow of random complete blocks with 3 replications. Wet planting with the use of line adopting with spring furrow and spaces of 75 cm increased the operation (p< 0/01) in compares with other attendances by 33%. Also, the harvest index showed a meaning full difference on the factor of space between row and type of planting at the type of furrow (p<0/01) the most operation of seed was related with the amount of 5467 kg related to wet planting and 75 cm rows space and use of line adopting with spring furrower and the least operation with the amount of 4133 kg was related to conventional planting. The results of calculations showed that wet planting has 15% more Irrigation efficiency in compares with tool steeling and conventional planting with irrigation efficiency of 2/184 kg /m3 was the least and planting on atmospheric and 75 cm mound with irrigation efficiency with 29% difference. So, planting with wet planting in rows of 75 cm with spring furrow was the most suitable attendance in increasing operation of seed and irrigation efficiency.