Aydın Ünay

The Waterlogging Tolerance of Wheat Varieties in Western of Turkey

This research was conducted to determine the wheat varieties against waterlogging which was clearly increased in recent years. For this purpose, this study was performed at Field Crops and Soil Science Department of Agricultural Faculty of Adnan Menderes University during wheat growth stages of 2007-2008. The experimental design was randomized complete block design with split split plot arrangements. The main plots were temperature applications (heat and normal), the growth periods (Zadoks scale; GS14, GS32, GS14 + GS32, and control) were split plots and varieties were split-split plots. The eight different wheat varieties were evaluated in the pots. The waterlogging was performed during GS14, GS32 and GS14 + GS32. In a pot experiment, plants were subjected to waterlogging to the soil surface for 10 days. All applications and varieties decreased the single plant yield. The waterlogging caused a yield loss compared with wheat grown on well-drained soil. In this study, the crop loss due to waterlogging is highly temperature dependent. The severity of the effects of the waterlogging depends on the growth stage of the plot. When all applications were compared with control by means of yield performance, Sagittario and Basribey varieties were less affected than the others.

Natural crossing and isolation distance between cotton genotypes in turkey

Os objetivos deste estudo foram determinar a percentagem de cruzamentos livres, a distância de isolamento e as especies de insetos polinizadores na producao de sementes de algodao (Gossypium hirsutum L.) na regiao de Aydin, na Turquia. Foram utilizadas as caracteristicas ausencia de glândulas e folhas vermelhas como marcadores de G. hirsutum. Dois experimentos foram conduzidos durante dois anos, nos quais os cruzamentos livres em linhas e plantas adjacentes foram monitorados, tendo sido comprovada uma variacao na percentagem de cruzamentos livres que variou entre 0 e 13,3% dependendo do marcador genetico. No experimento de determinacao da distância de isolamento, nao se observou cruzamento natural em 2002, mas em 2003 sua percentagem foi de 0,8%, apenas nas primeiras linhas. Neste estudo, os campos de algodao foram visitados uma vez por semana, por sete semanas, para determinar o numero de especies de insetos polinizadores, tendo sido encontradas abelhas produtoras de mel. O numero encontrado foi de 2,14% (2002) e 1,30% (2003) para linhas adjacentes; 1,71% (2002) e 2,00% (2003) para plantas em parcelas com ausencia de glândulas. E recomendado que a distância de isolamento entre genotipos deva ser de aproximadamente 1 m.

Integrated Weed Management in Cotton

Cotton (Gossypium spp.) is the most important fiber crop of the world, cultivated over a large area, and possesses several benefits. Fiber, food, feed, industrial products, and livelihood for a huge portion of population are some of the salient utilities of cotton crop. Cotton is perhaps the most problematic crop of the world, attacked by hundreds of insect pests, disease pathogens, and weeds. Weeds not only decrease the cotton production but also deteriorate the lint quality as well as harbor insect pests and diseases. Also, the composition of weed flora competing with cotton plants changes drastically with the changing set of management practices. The salient technologies for weed control in cotton include the application of preemergence herbicides, spray of postemergence herbicides, and the use of genetically modified herbicide-resistant cotton cultivars. Several other available options include the cultural weed control, weed control through allelopathy, and tillage. The techniques such as stale seedbed and use of allelopathy have special attraction for controlling weeds in cotton for their cost-effectiveness and environmental gains. Undoubtedly, the techniques are quite effective in suppressing the weeds and improving cotton growth. However, they are rarely implemented in an integrated way. Integrated weed management focuses on avoiding the causes of weed prevalence with basis from scientific knowledge and available management options rather than the mere reaction to the present weed flora. Most important considerations include limiting the weed population through implementation of all best available options so that the surviving weeds are least damaging for the crop. Nevertheless, systematically combining several of available effective weed control strategies as an “integrated approach” would aid for effective weed control in cotton, improved lint quality, cost-effectiveness, reduced risk of herbicide resistance development in weeds, and environmental conservation.

Su Taşkınına Maruz Kalan Bitkilerde Kök Gelişimi ve Hormonal Değişiklikler

Su taskini meydana gelen topraklarda havanin yerini su almaktadir. Su taskini, topragin suya doygun oldugu kosullarda bitki koklerinin toprakta yeterli oksijen olmamasi nedeniyle normal bir solunum yapamadigi ciddi bir problemdir. Kokler, su taskinlarindan kaynakli oksijen eksikliginde dogrudan ve ilk olarak etkilenen organlardir. Su taskini suresince, bitki kok gelisimi engellenebilmekte ve kok olumlerine neden olabilmektedir. Su taskinlarina bitkilerin tepkisi su taskininin meydana gelme zamani, topragin su altinda kalma suresi ve bitkinin cinsi, turu ve tur icerisindeki farkliliklarina bagli olarak degismektedir. Aerenkima olusumu ve adventif kokler uzun sureli su taskinlarinda hipoksi ve anoksi kosullara bitkilerin verdigi en yaygin tepkiler arasinda yer almaktadir. Oksijenden yoksun kok sistemleri ile hem kok hem surgun gelisimi icin yetersiz besin maddesi alimi gerceklesir. Toprak ustu aksamda su taskinina duyarli ya da daha az toleransli bitkiler fotosentez kapasitesinde meydana gelen onemli azalmalar nedeniyle zarar gorebilmektedir. Fotosentez kapasitesindeki dususun en onemli nedeni ise stomatal acikliktaki azalmadir. Su taskininin diger bir etkisi ise, buyume ve yaprak genislemesini saglayan bazi bitki hormonlarinin engellenmesidir. Ayrica etilen hormonu kok bolgesindeki oksijensizlige karsi bitkilerin hayatta kalabilmesi icin artis gostermektedir. Bu makalede, su taskinlarinin bitkilerin koklerinde olusturdugu degisimler ve hormonsal tepkiler incelenmistir.