Effect of solarization and vesicular arbuscular mychorrizal on weed density and yield of lettuce (Lactuca sativa L.) in autumn season

This study was conducted on trial field of Faculty of Agriculture, Dicle University, Diyarbakir, Turkey in 2007 growing season. The experiment established on a loamy- clay soil with the seedlings of Yedikulelettuce (Lactuca sativa L.) infected by Vesicular Arbuscular Mychorrizal (VAM) fungus, Glomus intraradices. The goal was to increase the yield and quality in lettuce production. The VAM infected and disenfected lettuce seedlings propagated in greenhouse conditions were planted by the split-plot designs-random model. The study was conducted as the main plot applied solarization and nonsolarization and subplot with VAM and without VAM which resulted in four repetitions. The solarized field had an increased soil temperature: the increase in the temperature was 11°C in 5 cm depth, 8°C in 20 cm and 5°C in 30 cm. This situation continued to the end of the growth season and also inhibited the germination of weed plants. In the solarized area, the plant height, plant crown-width and yield showed significant increase during the vegetative season of 45 days long. The data was significant for three growth factors. In solarized area, the average weight of lettuce was obtained to be 138.85 g but in control parcel the average weight was 30.85 g. The increases in VAM parcel for three growth factors were significant. But the interaction between solarization and VAM was found non significant. To determine VAM before testing in laboratory, VAM dutied like a bridge from donor lettuce to receiver wildmustard (Sinapsis arvensis L.) as observed in the experiment because mustrad has no symbiosis life with this fungus. Also the laboratory findings supported this; the number of spores, number of VAM infected and infection rate were higher both in main parcel of solarized and in the subplot parcel planted with VAM seedlings than the nonsolarized parcel and non VAM seedlings. The results for both criteria were significant in solarization and VAM application. But the interaction with VAM andsolarization was insignificant. As a result, one can note that the VAM inoculation after solarization application is beneficial for growing lettuce especially in the fall of season

Determination of long-term effects of consecutive effective fresh chicken manure with solarization and verticillium wilt (Verticillium dahlia Klebb) on weed and its control in egg plant

The aim of the study was to determine the weed density and the most economical way of weed control in eggplant (Solanum melongena) fields contaminated with Verticillium dahliae (Kleb) after the application of fresh chicken manure and solarization in the second year as the same crop was grown. The effect of solarization on weed and the labor need in weed control continued in a diminishing way in the consecutive observations. With fresh chicken manure (FCM), number of weeds (number m-2) decreased but their green and dry biomass (weights g m-2) increased. The labor need (d ha-1) to control the weeds decreased. Similar results were also recorded for V. dahliae inoculation. As a result of the study, 50% of labor saving was achieved in the plots of solarization and either FCM rate combinations [sol x FCM (12 kg.m-2); sol x FCM (6 kg.m-2)] compared to the control plots. Achieved savings in labor can afford to cover the costs of solarization and FCM.Key words: Soil solarization, fresh chicken manure, Verticillium dahliae, eggplant, weed, weed control