Ograniczanie wyników

Czasopisma help
Autorzy help
Lata help
Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 175

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  control
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The aim of this study was to determine the efficacy of Ichtio Hexan (a complex blend of Allium sativum extract, Chelidonium majus extract, Origanum vulgare extract, carvacrol and cinnamic aldehyde) for the control of spironucleosis (hexamitosis) in rainbow trout fingerlings. For this purpose, three groups of rainbow trout naturally infected with S. salmonis were fed diets containing either no Ichtio Hexan or supplemented with Ichtio Hexan at a rate of 0.1 ml/kg bw (group 1) or 1 ml/kg bw (group 2) for 38 days. During this period mortalities were recorded and the dead fish were examined to confirm the isolations of S. salmonis. At the end of the experiment the fish were sacrificed, individually weighed and measured, their livers removed and weighed. In order to determine the prevalence and intensity of infection the intestinal contents were examined. The results of the present study showed that Ichtio Hexan in an amount of 0.1 ml/kg bw considerably reduced mortality caused by S. salmonis in rainbow trout fingerlings. The number of S. salmonis trophozoites in the digestive tract after administration of Ichtio Hexan at this dose for 38 days was significantly reduced and limited only to the posterior part of the intestine. On the other hand, in the 1 ml/kg bw fed group none of the fish were infected and the gain in the body weight was significantly increased; however, the mortality rate was similar to the control group. The experimental groups did not differ significantly from each other with regards to the condition factor and hepatosomatic index. Considering the above findings, Ichtio Hexan at a dose of 0.1 ml/kg bw can be successfully used in rainbow trout farms to reduce the mortality rate in S. salmonis infected fish.
Diabrotica virgifera Le Conte has been present in Poland since 2005. The range of its distribution increased in 2006 and 2007. D. virgifera is known from areas of nine voivodeships in Southern and partially Central Poland. Current control strategy is based on containment measures to limit the spread of the pest from regions where it has occurred. This strategy includes the application of specific phytosanitary measures in defined parts of the country.
The effect of UV-C light as a means of control of natural mycobiota of grains of maize (Zea mays L.) hybrids “San Juan” and ”H-159” (productive cycle, 2009) was investigated. UV-C lamps of 15 W were used and the exposure times applied were 0, 5, 10, 15, 20, 25 and 30 min. The experiment was established in the randomised complete block design with eight and four replicates. The unit pilot was 50 grains. For the determination of mycobiota the agar plate test was used, after disinfection of the grains with sodium hypochlorite diluted to 3% for 1 min. Differences (P ≤ 0.001, P ≤ 0.05) between treatments were found, the best treatments being those of 30 and 10 min, observing reductions of 42.85 and 52.05% in the number of grains infected with Fusarium spp. with respect to control for “San Juan” and “H-159”, respectively. For Fusarium monoliforme it was found that in 30 min there was a reduction of 53.74% for the hybrid “San Juan”, while for H-159 a reduction of 61.7% in 10 minutes was observed. These results show that UV-C radiation may be useful for application as a germicide in future experiments on a wide variety of grains.
The efficacy of some plant extracts on the control of potato tuber soft rot caused by Erwinia carotovora ssp. carotovora was evaluated in the laboratory conditions. Neem leaf and seed aqueous extracts significantly reduced the incidence and severity of tuber soft rot, while ironweed and Siamese cassia aqueous leaf extracts gave moderate control of the disease. Tuber treatment with river redgum aqueous leaf extract did not control tuber soft rot.
The studies on biological control of damson-hop aphid (Phorodon humuli Schrank) on Marynka cultivar, using Aphidius colemani and Aphidoletes aphidimyza, were carried out in the hop-garden localised within Hop Experimental Station at Jastków over the years 1998–2000. The efficacy of Aphidius colemani ranged from 5% to 65% and was found sufficient to control damson-hop aphid in the period before flowering i.e. to the middle of July, but it was not sufficient later. The efficacy of Aphidoletes aphidimyza ranged from 50% to above 90% and it was sufficient in one of the examined vegetation seasons. High air temperature and lack of rainfall reduced efficacy of both species, but especially that of Aphidius colemani.
In the field experiments performed in 1999–2001 the profitability of late blight control in accordance with three decision support systems: NegFry,Simphyt and Stephan with routine fungicide program was compared. Potato protection carried out according to the recommendations of the decision support systems guaranteed higher profitability of late blight control than when potato was protected routinely. The highest profitability was recorded for susceptible variety Bekas protected according to NegFry.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 9 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.