No abstract

No abstract

Present study was carried out in the experimental field of the Field Crops Department, Faculty of Agriculture, Ankara University during 1999 and 2001. Two wheat cultivars, Gerek-79 and Gün-9, were studied to investigate the impacts of the removal of some photosynthetic structures including flag leaf, second upper leaf blade and awneds, on some yield related components. The experiment was laid out in a randomized complete block desing of split-plot restriction with four replications. According to results obtained, removal of flag leaf resulted approximately 13, 34, 24 % reduction in grain per spike, grain weight per spike and 1000-grain weight, respectively and 2.8% increase in grain protein contents in both years. Studies indicated that significant reductions in these traits and increases in grain protein contents resulted from removal second upper leaf blade and awneds.Key Words: Wheat, flag leaf, awneds, photosynthates Buğdayda Fotosentez Organlarının Uzaklaştırılmasının Bazı Verim Ögelerine EtkisiÖz: Anakara Üniversitesi Ziraat Fakültesi Tarla Bitkileri Bölümü deneme tarlalarında 1999-2001 yıllarında yapılan çalışmada; iki ekmeklik buğday ( Gerek-79 ve Gün-91) çeşidinde başaklanma döneminde, kılçık, bayrak yaprak ve bayrak yaprak altındaki yaprağın uzaklaştırılmasının bazı verim öğelerine etkisi araştırılmıştır. Deneme tesadüf blokları bölünmüş parseller desenine göre dört tekrarlamalı olarak yürütülmüştür. Elde edilen sonuçlara göre; kontrole karşılaştırıldığında bayrak yaprağı uzaklaştırılan bitkilerde; başakta dane sayısı, başakta dane ağılığ ve bin dane ağırlığında her iki yılda da yaklaşık olarak sırasıyla % 13, % 34 ve % 24 oranında azalma ve protein içeriğinde % 2.8 artış ortaya çıkmıştır. Bu öğelerdeki azalma ve protein oranındaki artış kılçığı ve bayrak yaprak altındaki yaprağı alınan bitkilerde de önemli bulunmuştur.

It is known that genetic diversity is the most important factor in classical and modern plant breeding. The considerable increase in the number of transgenic crops reveals the value of new plant genetic resources. In this study, a set of 12 wheat progenitors were screened for tissue culture parameters such as callus induction, callus weight, regeneration capacity of callus and callus efficiency using mature embryos. Embryos were excised from imbibed seeds of the progenitors. The excised embryos were placed scutellum upwards in dishes containing 2 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) for callus induction. The developed calli and regenerated plants were maintained on 2,4-D free MS medium. When mature embryos of 12 wheat progenitors (Aegilops sp. and Triticum sp.) were compared, significant differences were detected in callus induction frequency, weight of callus, regeneration capacity and culture efficiency. A significant genotypic effect was observed on the culture responses. Of the 12 wheat progenitors tested, Aegilops umbellulata had the highest regeneration capacity of callus. Aegilops biuncialis created the most regenerable calli because of the highest callus induction and culture efficiency. In the experiment, callus induction was significantly correlated with callus weight (r= 0.820) and regeneration capacity (r= 0.955). Weight of callus was significantly correlated with regeneration capacity (r= 0.740), while there was no significant correlation between callus induction frequency and culture efficiency (r= 0.350). Our results showed that, generally, mature embryos of some Aegilops and Triticum species have a high regeneration capacity, and therefore, can be used as an effective explant source for the successful application of biotechnology in crop improvement.

The influence of hybrid vigor on callus induction, callus weight, regeneration capacity of callus, culture efficiency and number of regenerated plants from mature embryo cultures of winter barley (Hordeum vulgare L.) hybrid was studied. A total of 15 F 1 hybrids and their parents were used for mature embryo culture. The statistical analysis of the results revealed that positive heterosis was noticed for all these characters except for callus weight. Plants regenerated in vitro were successfully established in soil.