تاثير رژيم آبياري بر برخي خصوصيات زراعي و فيزيولوژيك ژنوتيپ هاي بزرگ

چكيده انگليسي :

Effect of Irrigation Regimes on Some Agronomic and Physiological Characteristics of Flax Linum usitatissimum L Azam Kadkhodaie kadkhodaiea@yahoo com August 8 2009 Department of Agronomy and Plant Breeding Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Parviz Ehsanzadeh ehsanp@cc iut ac ir AbstractWater deficit stress acconts for a major part of annual crop losses including oilseed crops This research wasaimed at studying growth chlorophyll proline and soluble carbohydrate contents yield and yield components offlax genotypes under different moisture regimes A 3 replicate split plot RCBD field experiment was conductedat the Lavark Research Farm College of Agriculture Isfahan University of Technology Isfahan Iran in 2009 Three levels of irrigation based on evaporation from the standard Class A Pan consisting I1 as control irrigationafter 75 mm I2 as moderate drought irrigation after 115 mm evaporation and I3 as severe drought irrigationafter 145 mm evaporation served as main plots Six flax genotypes consisting C1 C2 C3 B Khorasan and 33were considered as sub plots Leaf Area Index LAI at early flowering stage chlorophyll content at anthesis proline and soluble carbohydrate content of leaves and plant height at 50 capsule formation stage capsules plant seeds capsule grain yield oil percent and yield biological yield and harvest index weremeasured while plant height suffered a 12 decrease under sever drought C1 and B genotypes indicatedsmallest and greatest plant heights respectively LAI was negatively affected by drought leading to an averageof 1 58 at I3 against 3 12 at I1 Khorrasan produced greatest LAI Irrigation regimes differed in terms ofchlorophyll content a 17 5 decrease observed under severe drought C3 and 33 genotypes indicated greatestand smallest chlorophyll content respectively Drought increased leaf proline and soluble carbohydrate contentby 174 6 and 21 42 respectively C1 and B genotypes produced greatest and smallest proline contents respectively Genotype B indicated greatest increase in soluble carbohydrate content Grain yield at I3 was36 28 lower than at I1 due apparently to the smaller capsules plant 23 05 seeds capsule 6 43 and seedweight 11 6 The greatest and smallest grain yields were observed with B and C3 Irrigation regime did notaffect seed oil percent significantly thoug the oil yield was 40 decreased due to severe drought The highest 781 04 kg ha 1 and lowest 273 4 kg ha 1 oil yield were observed with genotypes B and C3 respectively Irrigation regime left significant effect on biological yield with I1 5796 1 kg ha 1 outyielding I3 3982 9 kg ha 1 It could be concluded that drought affects flax growth and grain yield significantly and this negative effect ismainly through the decreased photosynthetic surface and chlorophyll content Leaf proline content variationsunder different moisture regimes does not necessarily indicate flax resistance to drought though it may reflectthe occurance of water deficit stress Increase of soluble carbohydrates content would be related to their role indevelopment of osmotic adjustment in latter oilseed crop under water deficit stress Key Words flax drought proline soluble carbohydrate chlorophyll yield

كدخدايي، اعظم

تاثير رژيم آبياري بر برخي خصوصيات زراعي و فيزيولوژيك ژنوتيپ هاي بزرگ

خشكي , پرولين , كربوهيدرات محلول , كلروفيل