Evaluation of bacteria for biological control of early blightdisease of tomato

Twenty three bacterial isolate out of 190, exhibiting inhibitory affects against Alternaria solani in preliminary tests, were screened for their activity towards A. solani Ell. and G. Martin) Sor. by a dualculture in vitro assay on nutrient agar (NA) medium and in vivo (whole plant) test. In vitro studies indicated that all the 23 bacterial isolates inhibited the mycelial growth of A. solani by forming inhibition zone ranging from 9.35 to 31.3 mm. The most effective isolate was Serratia plymuthica (IK- 139) (31.3 mm) based on the in vitro test results. Twenty three bacterial isolates were subjected to a whole plant test to investigate their ability to protect the tomato plant against early blight disease. In whole plant tests, 0.5 x 108 cfu/ml bacterial suspension was sprayed and one day later, A. solani spores suspension were applied on tomato seedlings and plants were incubated in moist chamber at 20°C with 95% relative humidity (RH) and 12 h photoperiods for 21 days. Based on the whole plant tests, Paenibacillus macerans-GC subgroup A (1.82), Serratia plymuthica (1.78), Bacillus coagulans (1.75), Serratia marcescens-GC subgroup A (1.50), Bacillus pumilis –GC subgroup B (1.50) and Pantoea agglomerans (1.32) bacterial isolates reduced the disease severity of early blight significantly when compared with control. These results suggest that the bacterial isolates studied have a good potential to be used as biocontrol agents of A. solani in tomato.Key words: Alternaria solani, early blight, biological control, bacterial isolate

Effects of shading and covering material application for delaying harvest on gray mold disease severity

To delay the harvest of Sultani Cekirdeksiz grape variety and to reduce pre and post-harvest botrytis bunch rot severity, shading and covering material application were tested in 2009 to 2010 growing periods. In this study, grape vines were shaded with shading materials which had three different shading densities (35, 55, and 75% shading density) from veraison period to harvest. The grape vines were also covered with four different covering materials (transparent polyethylene, mogul, polypropen cross-stich and lifepack) before rainfall, at the end of August until harvest. The gray mold severity was recorded three times (before shading at unriped grape stage, veraison period, shortly after shading and twice at 20 day interval) during growing period. Based on the results of this study, the highest gray mold (Botrytis cinerea) severity was obtained in the control (uncovered and unshaded) treatment and the lowest disease severity was observed in lifepack treatment with or without shading. Since gray mold disease of grape was the main factor affecting harvest date of the crop lifepack, + 35 or 55% shading could be recommended to delay harvest and reduce the gray mold severity of grape in Manisa province-Turkey.Key words: Sultani seedless, table grape, shading, cover material, delaying harvest disease severity, Botrytis cinerea

Fireside Corrosion in Oxy-Fuel Combustion of Coal

Oxy-fuel combustion is based on burning fossil fuels in a mixture of recirculated flue gas and oxygen, rather than in air. An optimized oxy-combustion power plant will have ultra-low emissions since the flue gas that results from oxy-fuel combustion consists almost entirely of CO2 and water vapor. Once the water vapor is condensed, it is relatively easy to sequester the CO2 so that it does not escape into the atmosphere. A variety of laboratory tests comparing air-firing to oxy-firing conditions, and tests examining specific simpler combinations of oxidants, were conducted at 650-700 C. Alloys studied included model Fe-Cr and Ni-Cr alloys, commercial ferritic steels, austenitic steels, and nickel base superalloys. The observed corrosion behavior shows accelerated corrosion even with sulfate additions that remain solid at the tested temperatures, encapsulation of ash components in outer iron oxide scales, and a differentiation between oxy-fuel combustion flue gas recirculation choices

Pigmentation of rainbow trout (Oncorhynchus mykiss) with carotenoids from marigold flower (Tagetes erecta) and red pepper (Capsicum annum)

The effects of diets including various natural carotenoid sources and synthetic astaxanthin on the pigmentation and growth of rainbow trout (Oncorhynchus mykiss) were investigated. Rainbow trout weighing about 111 g were fed diets containing 1.6%, 2.4% and 3.2% marigold flower; 4.4%, 6.6% and 8.8% red pepper; 100 mg kg-1 synthetic astaxanthin; and a control diet for 60 days. At the end of the experiment, synthetic astaxanthin provided the highest carotenoid accumulation in the fish flesh (6.42 mg kg-1) in the groups. This was followed by red pepper (5.78 mg kg-1) and marigold flower (5.59 mg kg-1), each of which included equal levels (100 mg kg-1) of carotenoids (P < 0.05). The fish fed marigold flower experienced yellow pigmentation, which was remarkably different from the other groups. An addition level of 2.4% or higher marigold flower and 6.6% or higher red pepper into the diet had negative effects on growth performance (P < 0.05). It can be concluded that the most appropriate dietary doses of marigold flower and red pepper for pigmentation of rainbow trout are 1.6% and 4.4%, respectively. © TÜBİTAK

Seasonal changes in total carotenoid contents of wild marine shrimps (Penaeus semisulcatus and Metapenaeus monoceros) inhabiting the eastern Mediterranean

Penaeus semisulcatus and Metapenaeus monoceros, harvested in January, April, July and October, were analysed for total carotenoid contents. During spring and summer, for both species, the carotenoid contents were considerably higher than in winter and autumn seasons p<0.05. Mean carotenoid contents of P. semisulcatus and M. monoceros were 14.1±0.45 and 16.9±0.26 mg/kg, respectively. These values are quite high compared to other seafoods. © 2004 Elsevier Ltd. All rights reserved.This study was supported by the Çukurova University Research Fund, PhD studentship (No. FBE.2001.D.37)

Seasonal Changes in Total Carotenoid Contents of Some Fish and Crustaceans Inhabiting the Eastern Mediterranean Sea

This study was conducted to determined the total carotenoid concentration of different body parts of green tiger shrimp (Penaeus semisulcatus), kuruma shrimp {Penaeus japonicus), speckled shrimp (Metapenaeus monoceros), blue crab {Callinectus sapidus), red porgy (Pagrus pagrus) and red mullet {Mullus barbatus) caught from the coast of the Eastern Mediterranean in February and October. The carotenoid levels of head, shell and whole body of all animals were higher in October than those in February while their muscle carotenoids were not affected by seasons, except for kuruma shrimp and speckled shrimp. Amounts of carotenoids were highest in the head, decreasing in shell (or skin) and muscle. Average total carotenoid concentration among body parts of species ranged from 16.19-55.44 mg kg-1 in green tiger shrimp, 16.77-74.92 mgkg-1 in kuruma shrimp, 17.24-66.36mgkg-1 in speckled shrimp, 6.41-14.34 mgkg-1 in blue crab, 1.37-28.77 mg kg-1 in red porgy and 1.30-39.26 mg kg-1 in red mullet. These values are quite high compared to other sea foods. Since, coloration plays an important role in consumer preference, it would be advantageous to fish these animals in October rather than February. © Medwell Journals, 2012

Control of powdery mildew (Leveillula taurica) on tomato by foliar sprays of liquid potassium silicate (K2SiO3)

A foliar application of soluble silicon (liquid potassium silicate) was tested for the control of powdery mildew of tomato for 2 years in the field conditions on susceptible cultivar Alida F1. Powdery mildew in field-grown staked tomato, caused by Leveillula taurica was significantly controlled by a foliar spray of either K2SiO3 or Bayleton + sulfur. Potassium silicate applied on a 12 day schedule was highly protective against natural infection by the mildew fungus in the field conditions. The disease severity indexes (DSI) were 77.5 and 74.7% in control plots in 2006 and 2007, respectively, and were significantly different (P &lt; 0.05) from those in the K2SiO3 plots with 5.8 and 4.6% in 2006 and 2007, respectively. Potassium silicate concentration (1 g/1 L water) used in the present study were not phytotoxic to plant foliage. The inhibitory effectiveness of potassium silicate makes it a useful biocompatible fungicide and possibly ideal foliar fertilizer for disease control in the field.Key words: Powdery mildew, potassium silicate, fungicide, tomato

Effects of hot and sweet red peppers (Capsicum annuum) as feed supplements on pigmentation, sensory properties and weight gain of rainbow trout (Onchorhynchus mykiss)

This study was conducted to evaluate the effects of diets, including 0.5, 2 and 4.4% dried hot or sweet red pepper and a control diet without added red pepper, on pigmentation, sensory properties and weight gain of rainbow trout, with average initial weight of 60 g, for a rearing period of 80 days. Both red pepper types had similar effects on the carotenoid accumulation, weight gain and sensorial properties of the fish (P>0.05). Total carotenoid accumulation in the fish muscle increased significantly with increasing inclusion of red peppers. However, only the diet consisting of 4.4% hot or sweet red pepper provided adequate carotenoid accumulation in the fillet of the fish, that is, the desired colouration in the fish. Fish fed diets containing red peppers exhibited higher appearance and colour scores compared to control group (P<0.05). Irrespective of being hot or sweet, red pepper can be successfully used as an alternative natural carotenoid source in rainbow trout diets. © 2016 Walter de Gruyter GmbH. All Rights Reserved.*This study was supported by the Çukurova University Research Fund (No. FBE.2002.D.218)

The effects of red pepper, marigold flower, and synthetic astaxanthin on pigmentation, growth, and proximate composition of Penaeus semisulcatus

Shrimps with an initial weight of 11.10 ± 0.26 g were fed diets supplemented with 6.6% red pepper (RP), 2.4% marigold flower (MF), and 100 mg/kg synthetic astaxanthin (SA), each of which contained 100 mg/kg total carotenoid, and a control diet (BD), without carotenoid supplement for 60 days. Dietary carotenoid sources did not significantly affect the growth of the shrimps (P > 0.05). SA supplementation yielded the highest survival rate (92%), followed by RP (82%) and the other diets (75%) (P 0.05). RP and SA resulted in a greater protein increase in shrimp muscle than MF (P 0.05). © TÜBİTAK