جستجوی مقالات مرتبط با کلیدواژه "cocoon shell" در نشریات گروه "زیست شناسی"

Silkworm rearing has been intermingled with the life and culture of the Khorasan Razavi people for a long time. This study was conducted to determine robust hybrids for economically important traits in mulberry silkworm Bombyx mori under numerous climatic conditions. To identify the most suitable hybrid for Khorasan Razavi climatic conditions, 14 imported hybrids were compared with four Iranian local hybrids. In the spring of 2021, rearing was carried out under uniformed laboratory condition by adopting standard method. The experiment was laid out in Completely Randomized Design (CRD) with four replications and 200 larvae per replication using procedure of GLM in SAS 9.2 in the Torbat Heydarieh sericulture center (Torbat Heydarieh, Iran). These eighteen hybrids were evaluated for their performance in eight metric traits viz., larval losses, percentage of pupae, percentage of cocoons (good, medium, weak and double), weight of cocoons (good, medium, weak and double), number per liter, weight of one liter, weight of cocoon cortex, percentage of cocoon cortex and percentage of raw silk. The results showed that Chines hybrid Q×B had higher cocoon weight with 339.57 gr (P <0.05). Also, L2×R had higher shell cocoon perecent with 24.36%  (P <0.05) and L2×OR showed higher average mean of cocoon wight with 1.72 gr (P <0.05). The result of the present study indicated that six hybrids viz., 872 × 871, B × Q, BB × QA, HB × JA, JA × HB, and M × S exhibited better performance in imported Chinese hybrids, and three Iranians hybrids viz., 103 × 104, 151 × 154, 154 × 151 had better performance in Torbat Heydariyeh region of Khorasan Razavi province.

The present investigation was carried out to evaluate the effects of dioxide titanium particles on growth and performance character. Based on previous works, it is expected that TiO2 nanoparticles (NPs) improving the feed efficiency and promote silk protein synthesis in the silkworm can be improved important traits such as cocoon shell weight and cocoon weight. The experiment was designed in a completely randomized design with three replications. Five groups of silkworms fed diets with dioxide titanium nanoparticles at 0, 5, 10, 50, and 100 mg/l in duration 4 and 5 instars. Data were analyzed by SAS software, and Duncan test was used to compare the mean. It was observed that the addition of dioxide titanium nanoparticles at different levels significantly improved percent viability, cocoon and cocoon shell performance compared control group.  In comparison to the control treatment, cocoon weights rose by 3.3 and 3.85 percent in 5 and 10 mg/l dioxide titanium, respectively. In comparison to the control treatment, 5 mg/l nanoparticles had a higher cocoon shell weight and cocoon shell ratio of 10.40 and 6.27 percent, respectively. Results showed that using dioxide titanium nanoparticles in 5 and 10 mg/l can increase cocoon and cocoon shell performance, but it has not effect on these traits with higher concentration.