نشریه بوم شناسی گیاهان زراعی
پیاپی 1 (بهار 1384)

ln order  to  evaluation    the  possibility of  true potato seed application    for potato  production,   An experiment conducted with six  true potato  seed families   includeing   three open pollination   Aula,   Kaizer and Dessire cultivars and three hybrid  families from  the crosses of paeizeh   x Dessire, paeizeh  x Kaizer and Aula x  Kaizer   in Ardebil Azad University   Agriculture   research  station.   Some agronomic   traits  such  as seedling stability,    Plant   hight,   number of stems,   plant  vigor,   number of tubers,   yield and tuber dry matter   were measured. The results of ANOVA showed that  there is  no significant   differences among  families  in  terms  of plant  hight, number of stems, seedling   stability and dry matter,  however differences   in  number of tubers, tubers   weight  and plant  vigor  were significant.    Paeizeh   x Dessire,   Payezeh x Kaizer with average of 21.3 and 20.4 tubers per plant  had the highest  and Kaizer  and Dczireh open pollination   with  average of 8 and 6.5 had the lowest  number of tubers per plant respectively.   Also  ranks of plant vigor  in Paeizeh   xDessirc  hybrid with the average of 3  and open pollination of Dessire with  the average of l.7 were the  highest   and lowest amounts respectively.    Also,   hybrid families were superiar   than open polliantions    in  term  of yield,   So that Paeizeh  =Desstre  with 20460 kg/ha was the highest  yielding   and Dessire  open pollination   with  6060 kg/ha was the least  yielding   families.  Analysis  of correlation  coefficient   showed   that  there are significant   positive relations   between yield   and agronomic traits includeing number of stems, number of tubers,   plant   vigor, seedling  success and plant hight.

Diamondback  moth,  Piute/la xylostella  L. is  a  major pest of Cruciferous  crops worldwide.   It  out broke in cabbage   fields  of Tehran province   in  1999 and   caused considerable   yield   losses.  Seven treatments  including  Biological   and Chemical   pesticides   were used in   the field  test.  These   treatments were as follow:  Consult  (EC I 0%) 0.4 kg/h & 0.5 kg/h, Carbaryle  (Wet able  powder  85%) 2.5  kg/h,  BtH (Iranian   product  as powder) I   kg/h & 2 kg/h, Dipel~  (Wet  able powder) 3  kg/h and  the control  in two factors  randomized  complete  block design  with split plot  combined  over times  in  four replicates.  The results  revealed  that  Consult  0.4  kg/h, Consult  0.5 kg/h, Carbarylc  2.5 kg/h and  Oipct®  3  kg/h  caused 79.09, 70.06,  70.01   and  65.77 percent larvae  mortality   respectively   and  were placed in  one  class  of Duncan's Multiple  Range Test. Btll  I   and 2 kg/h  had  less  effect on  this pest,  and was placed  in  another class.  Dipel  was also  more effective than  BtI-1  on Diamondback   moth larvae  in laboratory  bioassays.

Barley strip disease caused by Pyrenophora gramineae  is found in most of barley growing areas in the world and most part of Iran. This foliar disease  in barley  causes emptiness and extreme weakness of seeds and considerable yield losses. The disease is monocycle and seed-born and the fungus survives as mycelium in the hull,   pericarp and seed coat. Therefore,  the best way for disease controlling  is the eradication of seed born inoculum by different methods. In order to evaluate the effect of various thermal  and chemical  treatments on disease  control,  infected   seeds were  collected   from diseased  barley  fields  with  Prop star cultivar  and the infection   percent  was defined  approximately   89.5% with "Culture  plate test"  method. Thermal  treatments consisting  of  tennothcrapy  during  5  and  I 0 minutes  in  52 oC warm  water and chemical  treatments  with Carboxin-Tiram,   lrnazalil,  Mancozeb, Tilt and Maneb were applied.  Infected  seeds treated  with lap water were  considered  as  control  and  the project ran  in  completely  randomized  design.  For each  treatment,  20 treated seeds were sawed in three replications  in pots.  60 days after planting, the effects of various treatments on fungus seed-born inoculum and seed viability were studied by evaluation  of infected plant  percentage. The thermal  treatments were recognized to be unsuitable for seed disinfection   because of extraordinary and over than 50% effects  on seed viability   and low  effect  of disease control. Among chemical  treatments, lmazalil was the best  for disease  control and other treatments had significant  difference  with it. But there were no significant  differences  between  the  other  fungicides.  But application  of  Tilt  is  not  advisable  because  its significant effect on seed viability.

To investigate  adaptation  and effects of the  different  strains  of Rhizobium japonicum  on soybean cul ti var
and selective   of the  best cultivar and bacteria  strain,   an experiment   was carried  out in  Broujerd agriculture research  station.    A  factorial  design   with   4 replications    in the  basis   of randomized   complete   block   was applied.   Treatments  included three cultivars of soybean (Clark,  Williams   and  Zien)  and two  kinds  of bacteria strain (Helinitro  and Rizoking)  and a level  without bacteria   strain  (Control).   To determine  growth analysis, total  dry matter (TOM), leaf  dry matter (LOW) and leaf  area index   (LAI)   were measured,    and with three parameters   other growth  indexes were calculated.   The results  achieved   showed  that Williams cultivar and Helinitro    bacteria  strain ('' ith  high level  of nitrogen fixation)   had  better grain yield   and nitrogen  fixation efficiency   than  other cultivars   and strains.   These results obtained through  increasing   of the crop  growth  rate (CGR)  and leaf  area index (LAI),   which  these  factors increased   net  assimilation    rate (NAR) and  total  dry matter (TOM).   The control  plot  leaf  area index   and crop growth rate  were very low;  consequently,    net assimilation rate and total  dry matter decreased and grain yield  produced very low.

In order to study of irrigation intervals  and nitrogen splitting  effects on yield  and yield  components  of two spring  cultivars  of Canola (Brassica napus L), an experiment  was conducted  in Spring  2003, at research  station of college  of agriculture,  Ferdowsi University  of Mashhad.  Experimental   design  was a split - plot  factorial based on  completely  randomize   block  design  with  three replications.   The   main  plot   factors   including   irrigation intervals  (7,14   and 21  days) and Canola  cultivars   (ORO  and MIDAS)  and nitrogen  splitting  (100:0   (N1),      (25:72 (N2)   ,  (50:50  (N3) and (0: I 00 (N4))   were allocated  to sub plat whit a factorial  arrangement.  Results showed   that number of pods per plant,  weight  of I 000 seeds .biological  yield,   seed yield   and oil  percentage  were reduced
with  increasing  irrigation  intervals.  Oil  percentage were affected by nitrogen splitting.   The highest  oil percentage was produced in treatment  of N3 and N4•   The weight of I 000 seeds and oil percentage  were affctcd  by variety. ORO  produced the   higher weight  of seeds (4.2 gr) than   MIDAS (2 gr),  but  MIDAS  produced   more oil percentage  than ORO. Oil  percentage was increased  by reduction  of  irrigation   intervals.   The highest seed yield reduction  was observed \ ith increasing  the irrigation intervals. From the splitting   treatment,   N2 and N3  showed a better  performance.

Although  production  of hybrid corn kernel  is  low,  the value  per unit of yield  is  several   limes greater than that of seed grain.   The production   of hybrid  corn kernel   is  dependent  on timely   harvest  operations    that ensure maximum seed quality  and yield   of inbred parent and hybrid  seed.  The present research was conducted al the Experimental   Farm of the Islamic   Azad University  of Fasa during summer 2000.  The factorial   experiment was designed  based on complete  randomized   block  design   with 3 replications.     The factors were time of seed harvest during  various stages of kernel  maturity  and water deficit.   There were several  harvests from first week to third  week of kernel  maturity. The beginning  of kernel   maturity  was determined  from kernel   growth curve and the end of linear  grow th phase. Water  deficit   consisted   of control,   early and late  water deficit   after pollination. As the aim of this  investigation   was to study of corn kernel  harvest different   times  during   the stages of kernel maturity and the efTects of water deficit  on kernel   quality  characteristics,    kernels  of Sc 704 hybrid parent were seeded. Dry matter weight   and moisture percentage of kernels  and starch and protein percentage  of kernel   was determined   and used for the explanation  of germination  percentage and vigor changes of the kernels.  The results showed that  kernel  kernel  maturity  began from seventh week after pollination   and last  three weeks.   Statistical analysis   of kernel  dry matter weight  showed significant  effect at 5% probability  level  during this three weeks of the  water deficit. Also  early and late  water deficit   reduced kernel  embryo dry matter weight  by average 28.92% and 7.53% respectively   during  kernel    maturity.   Kernel   moisture  percentage  has shown  significant  difference only    during   the  first week of kernel  maturity.  The  germination    percentage  of com  kernels   produced  during kernel   maturity stages was determined. The results  showed that kernel germination  percentage was minimum  in control  treatment during first week of kernel  maturity (27%) and it  was maximum (92%) during the third week of maturity. A linear relationship    was obtained between germination  percentage  and kernel embryo dry matter weight  in control  and late  water deficit  treatments. Seedling dry matter weight  obtained from germination  of the first - week seeds was not affected by water deficit.

An  investigation    was  carried   out  on    yield,    yield    components   and  some   agronomic   traits evaluation    of sunflower  cuJtivars,   as  Randomized    Complete  Block   Design  at 4 replications   in Khoy  as summer   second  cropping   in  Agriculture   Jihad   Research   Station  during  2003.    In  this  experiment    12 sunflower   varieties   including  4 commercial   hybrids,  I lysun-33,   Azargol,   Allstar,    Euroflor,  6 new Three Way Cross  hybrids,  RI03*  Fl/7,   Rl03*    Fl/2,   Rl03*  Fl/16,   R95*  Fl/26,   Rl03*  Fl/l,Rl03*     Fl/18,    and two   open-pollination      varieties,     Record   and   Armavirecki,      were   planted     in  Tir   eleventh     (2   July). Experimental     results   revealed    significant    difference   among   the  features  of   the  varieties   indicating remarkable  diversity   of the  varieties  traits  in summer  second cropping  and the possiblity  of choossing  the excellent  variety  among  them.   Among  experimental    varieties,  hybrid  Rl03*   Fl/7  with average  growing season  of 93 days,  and Record  variety  with average  growing   season  of  104.   5  days were early  and delay ripening  varieties   respectively.    New T.  W.  C.  hybrids  with  average  growing  season  of 93-96 days,  were early  ripening  than all  of the commercial   hybrids  except  for Allstar   hybrid.   This  hybrid  with 94 days of growing  season  had no significant   different   with  new hybrids.  Record  variety  enjoyed  remarkable  plant height   among  other  varieties    excluding   Euroflor  and  Allstar  varieties,    but  other  varieties  showed   no significant    difference  as regards  this feature.  The highest  tray diameter  was seen first in Hysun-33  hybrid, and then in Record  and Rl03*  Fl/26  hybrid.   Weighty  seeds with average  test weight  of 57.70  and 57.19 were  seen  in  Record  and  Hysun-33  varieties  and the greatest  number  of seeds  in tray were  also  seen  in aforesaid  varieties.   The highest seed yield  related  to Hysun-33  hybrid with average 4004 Kg/ha  but due to lowness  of oil percent  in this  hybrid  (41.16    %) Record  variety  with  oil yield of  1839   Kg/ha comes  first among  others  and  Hysun-33  hybrid  with  oil yield   1646   Kg/ha  comes  second.   Then  come  Azargol  and R95* Fl/26 hybrids  with respective  average  seed yield  of 3116,    2967 and oil  yield of  1515,  1347   Kg/ha as  far as  the  amount  of  this  feature  is concerned.   Studying  of correlation  yield  and yield   components showed   that  there  exists   a  positive   and  strong  correlation   between   seed  yield   and  test  weight.   The experiment  results showed  that due to the region's   conditions,  planting  of delay  ripening  varieties  such as Record  and  Hysun-33  on timely  and  prematurely  can  have  the  highest  seed  yield   and  oil yield.   But  if there  is   limitation    of  planting    season,   early   ripening  hybrids  such  as  R95*  Fl/26   and  R103*     Fl/18 without   having   significant    difference  in  terms  of seed  and oil yield   with  above  mentioned  varieties,  are suitable    for  cultivation    as  second  cropping   in  region.    Provision    of  new  hybrids  with  enjoy  of  early ripening,  high seed and oil yield,   can lead  to the expansion   of area or sunflower  planting  in  the region.

This  study  was conducted   for investigation   of the effect of three between  plant   20, 25 and 30  cm on
60  cm  fixed   rows  and  early  ripeing    three  cultivars  Zaria,Azargol    and  Chemianca     on  different  triat including yield  and yield   components in Sunflower  after Barty  harvasting    in Miyaneh   region   during 2003. A fectorial   experiment    with randomized    complet   block design   and  3  replication     was  used.  In  this study some  of  vegitative    and   reproductive     stages,  morphologyeal     charactristics,     dry  wieght  various   organs, yield    and  yield   components    and  harvest   index  was  evaluated.    On  the  obtained    results,    there  was  no significant    difTerencc    between    plant  densities      in   phenologycal     stages,yicld     components      and   must   of evaluated   traits  except  I 00 grain weight   and grain  yield.   Also   there was no  significant    difference  between planted cultivars the must  evaluated   triats  except shrub length  and husk  to seed portion.ln    this  experiment diffrcnce   of interaction    of density    and cultivars   with   studied   trait  wasn't   significant    except   dry wight to second  sampling.The    must  dry wieght   was obtained  in the 83000   plant/ha    tretment  with Zaria and the
55000 plant/ha tretrnent   whit  Chemianca    was the least  dry wieght.   Finaly, considering    with experimented conditions   in this study the density   of 63000 plant/ha with Azargol   for double   cropping of sunflower    is suitable for Miyaneh region.