نشریه یافته های نوین کشاورزی
سال چهارم شماره 2 (پیاپی 14، زمستان 1388)

In order to investigate the influence of bush accumulation and division of nitrogen fertilizer on jiroft local sesame، an experiment was done on split plot design based RCBD with four replications. Accumulation as a major factor in four bush levels (10، 13. 3، 20 and 40) in square meter and Nitrogen fertilizer divisgon in three levels (20-100-30)، (50-50-50)، (50-70-30) kg/ha were investigated. The results indicated that bush accumulation affected seed and biolgie function، number of capsul in bush، number of capsul in bush، number of foliage and height the effect of nitrogen fertilizer division is on seed function، biologic function، seed weight، number of capsul in bush، number of seed in capsul، number of secondary foliage and height. Average of nitrogen fertilizer comparison indicated that the highest seed function by 1727 kg/ha was obtained in division (50-50-50) kg/ha in pure nitrogen. Bush accumulation comparison indicated that the most seed function (1912 kg/ha) was achieved in accumulation of 40 bushes/m2. The mutual effects of bush accumulation and nitrogen fertilizer division showed that most seed function as 2044 kg/ha was in accumulation of 40 bushes/m2 and with usage of (50-50-50) pure nitrogen in kg/ha.

In order to determine the best rate of nitrogen and row spacing of rapeseed، Hyola 308، this research work was carried out in paddy field of RRII (Rasht، Iran) during 2004 – 2005. A factorial experiment was performed based on RCB olesign with three replications. The treatments were row spacing at three levels: 20، 25 and 30 cm and four nitrogen fertilizer rates: 0. 7، 1. 0، 1. 3 and 1. 6 R from urea source، based on soil testing and soil and water research institute recommendation. The R factor was 140 kg urea/ha. In this research work، some important agronomical traits such as number of pods per main stem، number of pods per auxiliary branches، number of pods plant، number of seeds per main pod، number of seeds per auxiliary pod، number of seeds per pod، 1000 seed weight، grain yield، oil percent and oil yield were studied. The results of analysis of variance showed that non significant differences exist between row spacing for grain yield. However، row spacing of 20 cm was relatively superior with an average grain yield of 1908 kg/ha. Interaction between row spacing and nitrogen rate on grain yield was non significant. Fertilizer rate of 1. 6 R and row spacing of 20 cm with average 2291 kg/ha had maximum grain yield. Interaction between row spacing and nitrogen rate on oil yield was non significant but row spacing of 20 cm and fertilizer rate of 1. 6 R showed maximum oil yield.

In order to determination of Cycocel application effect on barley cultivars (Hordeum vulgar L.) under different sowing date، an experiment was carried out at split factorial in randomized completely block design with three replications at Mazandaran province in 2009-2010. Main factor was sowing dates in three levels including 7 and 26 November and 11 December and sub factor was three varieties including Sahra، Productive and M12 and cycocel rates in two levels including 0 and 2. 8 lit/cycocel ha. Results showed maximum and minimum of the spike per plant، grain per spike، and grain yield were obtained on 26 November and 11 December، respectively. Sahra and M12 varieties had to most and least of the spike length، tiller per plant، spike per plant، grain per spike، 1000 grain weight and grain yield، respectively. With application of the cycocel، decreased of the stem length، but increased of the spike length، tiller per plant، spike per plant، grain per spike، 1000 grain weight and grain yield. Maximum and minimum of the spike length، tiller per plant and grain yield were obtained in interaction of the 26 November × sahra cultivar and 11 December × M12 varieties. Therefore sowing date of the 26 November، sahra variety and application of the 2. 8 lit/cycocel ha because of the most of increased the yield components and due to grain yield introduced the best of treatment.

In order to investigate the effects of row spacing (45، 60 and 75 cm) and plant density (50، 65 and 80 thousand plants per hectare) yield and yield components of maize Sc 711 an experiment was done in the university research farm of Abhar Islamic Azad University in 2006. It was done by using a factorial experiment based on CRBD with four replications. Different developmental stages of maize include 50% emergence، transition from vegetative to reproductive stage، pollination and physiological maturity، plant height and stem diameter in transition stage، dry weight of various organs، yield and yield components and harvest index were studied. With increasing row spacing، stem dry weight in the pollination and physiological maturity، seed weight، grain yield، harvest index and grain number per ear significantly increased. Increasing plant density، leaf dry weight in transition، opening pollination and physiological maturity، stem dry weight in stages pollination and physiological maturity، ear dry weight and grain yield under the effect of density was studied and other traits plant density was not affected. The interaction between row spacing and plant density on stem dry weight in physiological maturity stage، stem diameter in opening pollination stage and grain yield were significant. Finally، knowing that with annual tests can not be a recommendation، but the results may be based on 75 cm row spacing with a density of 8 plants per square meter for the production of maize Sc 711 under conditions similar to this experiment can be recommended.

This research was done to investigate the effect of nitrogen fertilizer and furrow irrigation methods on quantity and quality yield of tobacco، Coker 347 cultivar. It was done at research farm of Rasht tobacco research center during 2008-2009. The experiment was conducted on a split plot design based on CRBD with 3 replications. Major factor was considered nitrogen fertilizer (45، 55، 65 Kg/ha) and minor factor was considered as irrigation (one way، two ways and no irrigation). Irrigation time was determined by tans meter device and in each turn soil irrigation was performed to the extent of field capacity. Tobacco product has been harvested in 5 sorts. Results showed that leaf length، dry leaf weight، sugar، chlorophyll، plant height were significant (P<1%) and leaf width and nicotine were significant (P<5%). Generally applying irrigation caused to increase of tobacco yield while two ways irrigation method had more effects. Applying 45 kg nitrogen/ha caused to maximum yield in major factors.

In order to determine the effects of different substrates on quantitative characteristics of greenhouse cucumber of Negin cultivar and also to study the possibility of mixing of perlite in different substrates، an experiment laid out in a randomized complete block design with nine treatments and four replication was carried out in a personal greenhouse in 2010. Characters including yield، the number of fruit، plant high، were measured and examined during this experiment. The results showed that different substrates significantly affected many measured characteristics as follows: peat moss with 2998 gr of fruit weight had the highest yield and leca with 355 gr of fruit weight had the lowest yield between the whole treatments. And also between the treatments، peat moss with 54 numbers of fruit per pot had the most fruit number and leca with less than 8 fruit number per pot had the least number of fruit averagely. Peat moss with the average of 179 cm had the highest high and leca with 56. 5 cm had the lowest high between the substrates. The results also showed that the mixed perlite made some changes in the most measured characters in substrates compared to the pure one.

In order to investigate the quantity and source of nitrogen and nitrogen coated urea on yield and growing index in sunflower hybrids، an experiment was conducted in research farm of Agricultural Jahad Organization in Arak during 2006. The main goal of this research was determining the suitable quantity and kind of nitrogen application to reach the maximum grain yield and oil yield of two sunflower cultivars in climatic conditions of Arak as provincial center of Markazi province. The experiments was done with different treatments of nitrogen and nitrogen coated urea each in 3 levels (25، 50، 100 kg/ha) of recorded cultivar and Liza–R–M hybrid based on factorial experiment in RCB with four replications. Some of compared characteristics were considered as، plant height، hay yield weight، head diameter، disk seed weight، 1000 seed weight، seed yield، harvest index، oil percentage، oil yield and rate of crop growing. The result of experiment showed that application of different nitrogen levels had significant difference on the rate of growing but the oil percentage had no differences. The highest grain yield was related to record cultivar with average 3. 36 ton/ha and the treatment of 100 kg/ha nitrogen coated urea with average 3. 96 ton/ha. The comparison of different treatments showed the highest increase in the crop growth rate in treatment of 100 kg/ha nitrogen coated urea much more than the others.

Salinity is one of the most important of factors decrease crops yield. Tolerance of plants to salinity between species plants is different and is at the influence of plant growth environmental. One of the most practical and economic method for decrease saline stress in saline lands is release the saline tolerant varieties. In this experiment 19 barley lines and one current native cultivar compared with a randomized complete block with four replicates in Esfahan Saline Research Station during 2004-2005. Electrical Conductivity of soil was about 9 ds/m and plants were irrigated with saline water (EC=12 ds/m). Some traits such plant height، total dry matter، number tiller per plant، number fertile tiller per plant، spike length، number spike per m2، number spiklet per spike، number grain per spike، 1000 grain weight and grain yield of each genotype measured and base on this traits in final the most tolerance genotypes selected. Base on results of ANOVA variance and for base on plant height، number tiller per plant، number fertile tiller per plant and grain yield of lines، line of ICB119146 (line 7)، with 3867 kg/ha yield was best line. In final، base on the results about grain yield can line 7 for adoption experiment and replace to current native cultivar recommend.