scholarly journals Impact of photoperiod on circadian sucrose and sucrase rhythms in the digestive system of silkworm, Bombyx mori.

2013 ◽  
Vol 5 (1) ◽  
pp. 230-241
Author(s):  
E. Bhuvaneswari ◽  
B. Sailaja ◽  
S. Sivaprasad

The impact of photoperiod on circadian sucrose and sucrase rhythms were analyzed in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release or uptake cycles in gut lumen. The gut wall comprised 6 sucrose synthetic cycles (SS cycles) under LD, LL and 5 under DD. The 24 hr rhythm of LD and LL was clock shifted to 28.8 hr under DD. In gut content, the sucrose rhythm showed 7 sucrose uptake cycles (SUcycles) under LD, 6 under LL and 5 under DD and the 24 hr rhythm of LD was clock shifted to 28.0 hr under LL and 34 hr under DD. In the gut wall sucrase rhythm maintained 7 SES cycles under LD and DD and 9 cycles under LL and its 24-hr rhythm is advanced to 18.2 hr. In the gut lumen 5 SER cycles under LD, 8 under LL and 6 under DD and its rhythm is advanced to 15 hr under LL and 20 hr under DD. Further analysis of data showed that LD favoured both synthesis and uptake of sucrose while LL, favoured the sucrase synthesis and its release.

2013 ◽  
Vol 5 (1) ◽  
pp. 82-94
Author(s):  
E. Bhuvaneswari ◽  
S. Sivaprasad

Circadian trehalose and trehalase rhythms were studied in the digestive system of Bombyx mori under 12 hr light-dark cycle (LD), continuous light (LL) and continuous dark (DD). The rhythmic changes were interpreted as synthetic cycles in gut wall and release cycles in gut lumen. The trehalose rhythm of gut wall comprised 8 trehalose synthetic cycles (TS cycles) under LD and LL and 7 under DD. The 24 hr trehalose rhythm of LD and LL was clock shifted to 27.2 hr under DD. The trehalose rhythm included 4 TR cycles under LD, 5 under LL and DD in the gut lumen and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and DD. In the gut wall trehalase rhythm maintained 8 trehalase enzyme synthetic cycles (TES cycles) under LD, 10 LL and 7 under DD and the 24 hr rhythm of LD was clock shifted to 19.2 hr under LL and 27.2 hr under DD. In the gut lumen it included 4 TER cycles under LD and DD, 5 under LL and its 24-hr rhythm was advanced to 19.2 hr. Further analysis of data showed that LD favours trehalose synthesis, while LL and DD favour trehalase synthesis.


2011 ◽  
Vol 3 (1) ◽  
pp. 38-50
Author(s):  
B. Sailaja ◽  
S. Sivaprasad

The photoperiod-induced clock-shifting in the free running time of the circadian protein and amino acid rhythms was studied in the larval fat body of Bombyx mori. The analysis of peaks and troughs of phase response curves of the rhythm revealed that the fourth and fifth instar larvae grown under normal 12 h light and 12 h dark cycle (LD) showed 7 protein synthetic cycles, while those reared under continuous light (LL) recorded 9.5 cycles in fourth instar and 8 in fifth instar. Under continuous dark (DD), the protein rhythm maintained 8 cycles in fourth instar and 7.5 cycles in fifth instar. Clearly, both LL and DD conditions advance the 24-h free running time of the protein rhythm by durations ranging from 1.6 to 6.5 h. Comparative analysis of protein and amino acid rhythms shows that the photoperiod modulates the free running time of the former by altering the rate of amino acid mobilization.


2010 ◽  
Vol 2 (1) ◽  
pp. 48-56 ◽  
Author(s):  
B. Sailaja ◽  
S. Sivaprasad

Circadian rhythms in the silk gland protein profiles of Bombyx mori were analyzed under 12 h light and 12 h dark cycle (LD), continuous light (LL) and continuous dark (DD) conditions. The phase response curves of protein rhythms indicate the prevalence of a series of silk cycles, each comprising three phases; transcription, translation and consolidation of silk proteins. In the 24h- protein rhythm, the silk cycle repeats every 3h, 42 m under LD, 2h, 36m under LL and 3h under DD. The light and dark conditions advanced the rhythm of each silk cycle by 48m and 24m respectively. As a result the silk gland completes 7 rounds of protein synthesis under LD, 9 rounds under LL and 8 rounds under DD during the 24h-free running time of the rhythm. The light-induced clock-shift in the protein rhythm caused significant gains in economic parameters of sericulture with positive signals for enhancing silk productivity and quality.


Author(s):  
Shifa Vanmathi. J

<div><p><em>Studies were  carried  out  on  the  impact  of supplementation of Zea mays flour on  silkworm  Bombyx mori  belonging  to double hybrid variety (PFD).  The 3<sup>rd</sup>,4<sup>th</sup> 5<sup>th</sup>  instars    larvae  were  feed  with  leaves  supplemented  with different concentrations of Zea mays flour.  Maximum  larval  weight  was  observed in  5<sup>th</sup> instar  larvae  in 10% Treatment (4.59±0.31g )  and  5% Treatment (3.98±0.23g ) as compared  to  the control (3.13± 0.14g ).Mulberry leaves  treated with Zea mays flour  protein (10%)fed  larvae  recorded a  maximum  cocoon weight (2.32±0.07g),  pupal weight (1.53±0.12g) shell weight (0.42±0.02g) , shell ratio (24.55±0.62%)  silk filament length  (851.11±6.94m)  silk filament  weight (0.51±0.04g). Shell  ratio  in this treatment  (10%)  showed  an  increase of 18.38 %  over  control filament  length  21.64% . Larvae fed with mulberry  leaves  enriched with  Zea mays flour  protein  showed  significant  enchancement  in  economic characters of Bombyx mori was  traced.  </em></p></div>


2011 ◽  
Vol 3 (2) ◽  
pp. 176-188
Author(s):  
S. Sivaprasad ◽  
B. Sailaja

The photoperiod-modulated clock-shifting in the circadian protein rhythm was studied in the segmental muscle of Bombyx mori. The analysis of phase response curves of the fourth instar rhythm revealed that the muscle tissue completes six protein synthetic cycles (PS cycles) under normal 12 hr light and 12 hr dark cycle (LD), 8 cycles each under continuous light (LL) and continuous dark (DD) conditions. The fifth instar protein rhythm showed seven PS cycles each under LD and DD conditions, but only six under LL. The protein rhythm gets clock-shifted in instarspecific and photoperiod-specific fashions. In the fourth instar, both LL and DD conditions advanced the 24 hr free running time of the rhythm by six hours and set it at 18 hr, but in the fifth instar it is delayed by 4 hr and set at ~28 hr under LL, but remained unchanged under DD. Comparative analysis of protein and amino acid profiles shows that the photoperiod modulates the protein rhythm by altering the rate of amino acid mobilization.


Author(s):  
Rubia Bukhari ◽  
Kalpna Sudan

Sericulture is a commerce that involves the cultivation of mulberry plant species, the raising of silkworms, and the manufacture of silk. It is a sustainable, eco-friendly, and agricultural focused commerce. It is one of the largest employment industries, and it has played a significant role in rural opportunities and financial progress. The silkworm is the greatest mulberry assessor since different mulberry   types differ in numerous characteristics. Criteria for assessment have been created using a bioassay of silkworm larvae. The impact of a specific mulberry variety on a certain silkworm hybrid may be assessed based on growth/development, survival, and eventually cocoon generation, which directly influences silk productivity.


Planta Medica ◽  
2012 ◽  
Vol 78 (11) ◽  
Author(s):  
KS Ryu ◽  
HS Lee ◽  
KY Kim ◽  
MJ Kim ◽  
PD Kang ◽  
...  

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