SYUDY ON THE ECONOMICAL FITNESS DURATION OF SILKWORM, BOMBYX MORI L. EGGS, PRODUCED BY DIFFERENT METHODS | Проучване върху продължителността на стопанска годност на бубени семена произведени по различни методи
2010
Tsenkov, P., Sericulture and Agriculture Experimental Station, Vratza (Bulgaria) | Avramova, K., Agricultural University, Plovdiv (Bulgaria) | Grekov, D., Agricultural University, Plovdiv (Bulgaria)
The study has been carried out at the Sericulture and Agriculture Experiment Station – Vratza and Agricultural University – Plovdiv during the period 2007 – 2010. Under "economical fitness" it was accepted the duration of time, during which the silkworm eggs preserve a hatchability over 75 %. The economical fitness had been tested in different silkworm strains and hybrids while the eggs were produced by the following four methods: Method 1: hibernating, laid in June, obtained economical fitness in March of the next year; Method 2: hibernating, laid in June, obtained economical fitness in November of the same year; Method 3: laid in June, HCL treated 24 hours after the beginning of oviposition and obtained economical fitness immediately after the acid treatment; Method 4: laid in June and put under 2.5 o C at the 48th hour after the beginning of oviposition, then HCL treated after 3 to 60 days and obtained economical fitness immediately after the acid treatment. It was detected that the silkworm eggs produced by method 1 preserved their economical fitness within 150 days, by method 2 – within 200 days, by method 3 – within 90 days and by method 4 – within 120 to 180 days - depending on whether the HCL treatment was performed after 3 or 60 days preservation under cold storage. As result of the present study it is recommended in the silkworm egg production by HCL treatment to use the method of egg preservation under low temperature with a subsequent HCL treatment aiming at providing of a longer economical fitness. In order to produce silkworm eggs, suitable for rearing throughout the year it is recommended to combine the methods one, two and four.
显示更多 [+] 显示较少 [-]