• International Journal of Industrial Entomology and Biomaterials
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• v.2 no.2
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• pp.111-117
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• 2001

Screening of fifteen bivoltine silkworm breeds of Bombyx mori Linn at a temperature of $31{\pm}1^{\circ}C$ and relative humidity of 85${\pm}$5% resulted in the identification of eight thermo-tolerant breeds. The survival and cocoon shell ratio of the tolerant breeds ranged from 72.7 to 78.7% and 20.0 to 20.1% respectively. The tolerant breeds comprised of four oval breeds and four dumb-bell breeds. Eight foundation crosses prepared by crossing the oval and dumb-bell parents among themselves were screened at a temperature of $31{\pm}1^{\circ}C$ and relative humidity of 85{\pm}5%. The performance of the foundation crosses on 11 economic characters were analysed by employing Multipie Trait Evaluation Index method. Four foundation crosses which scored average index value > 50 were selected as breeding parents and breeding initiated for the evolution of thermo-tolerant bivoltine silkworm breeds. The methodology and the results of the foundation crosses reared both at 31{\pm}1$^{\circ}C$ and at $25{\pm}1^{\circ}C$ temperatures, are discussed.

• International Journal of Industrial Entomology and Biomaterials
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• v.6 no.2
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• pp.171-178
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• 2003

Four thermo-tolerant lines of silkworm, Bombyx mori, (L.) viz., A HT, B HT (Chinese type) and F HT, G HT (Japanese type) were evolved by utilizing the breeding resource material (identified from initial screening at a temperature of 31 ${\pm} 1^{\circ}C$ and relative humidity 85 ${\pm}$ 5%) through conventional breeding. These tolerant lines were crossed with productive breeds and forty four hybrids were evaluated on eight economic traits by the Multiple Trait Evaluation Index Method. Ten hybrids were short-listed based on the average evaluation index value larger than 50 for eight economic traits studied. The identified ten hybrids recorded higher index values (＞ 50) for most of the traits studied. Single hybrid G ${\times}$ CSR12 indicated average index value larger than 50 for six traits viz., pupation number (58), cocoon weight (67), shell weight (65), average filament length (74), raw silk % (69), reelability % (51) except for shell ratio % (41). The standard deviation of the cocoons in the above hybrid was 8.41 in the hybrid cocoon length and width measurement. However, two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 recorded average index value larger than 50 for all the traits viz., pupation number (57, 60), cocoon weight (50, 54), shell weight (56, 57), shell ratio percentage (59, 53), average filament length (55, 60), raw silk percentage (63, 67) and reelability percentage (53, 53). The standard deviation of the cocoons in the two selected hybrids viz., A ${\times}$ CSR5 and G ${\times}$ CSR13 was 8.41 and 8.06 respectively in the cocoon length and width measurement.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.370-377
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• 1999

Thermo-tolerant bacterium producing the xylanase was isolated from soil and identified as Bacillus pumilus. This strain, named Bacillus pumilus TX703, was able to grow ad produce xylanase at the culture temperature of 5$0^{\circ}C$. The maximum xylanase production was obtained when 1%(w/v) birchwood xylan and 1% (w/v) soytone were used as carbon source and nitrogen source, respectively. The biosynthesis of xylanase was under the catabolite repression induced by glucose in the culture medium, and it was completely inhibited in the presence of 0.2% (w/v) glucose. The maximum activity of xylanase was observed from pH8.0 to 9.0 and from 50 to 6$0^{\circ}C$ and the enzyme was highly heat-stable, whose activity remained was over 50% at 8$0^{\circ}C$, and was quite stable from pH5.0 to 10.0.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.53-58
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• 2004

Studies on heterotic expression in the silk productivity of 66 thermo-tolerant bivoltine hybrids reared under high temperature $(36{\times}1^{\circ}C)$ and low humidity (60${\times}$5%) conditions revealed that manifestation of heterosis was highly significant for majority of the quantitative traits contributing to more cocoon productivity. Observations were made on 8 economically important traits such as fecundity, pupation rate, cocoon yield, cocoon weight, cocoon shell weight, cocoon shell ratio, cocoon filament length and raw silk. Analysis of variance results revealed great deal of variability indicating significant (P < 0.001) variations. Out of 66 hybrids, 7 hybrids exhibited positive heterosis for seven traits and 4 hybrids expressed significant hetero-beltiosis for 6 traits, out of 8 traits evaluated. Based on results, the hybrids ${SR_1} {\times} {SR_5}and {CSR_2} {\times} {SR_5}$ are adjudged as most promising ones and can be exploited commercially in tropical climates to increase the cocoon productivity.

• Animal Bioscience
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• v.35 no.11
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• pp.1635-1648
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• 2022

Thermal stress due to extreme changes in the thermal environment is a critical issue in cattle production. Many previous findings have shown a decrease in feed intake, milk yield, growth rate, and reproductive efficiency of cattle when subjected to thermal stress. Therefore, selecting thermo-tolerant animals is the primary goal of the efficiency of breeding programs to reduce those adverse impacts. The recent advances in molecular genetics have provided significant breeding advantages that allow the identification of molecular markers in both beef and dairy cattle breeding, including marker-assisted selection (MAS) as a tool in selecting superior thermo-tolerant animals. Single-nucleotide polymorphisms (SNPs), which can be detected by DNA sequencing, are desirable DNA markers for MAS due to their abundance in the genome's coding and non-coding regions. Many SNPs in some genes (e.g., HSP70, HSP90, HSF1, EIF2AK4, HSBP1, HSPB8, HSPB7, MYO1A, and ATP1A1) in various breeds of cattle have been analyzed to play key roles in many cellular activities during thermal stress and protecting cells against stress, making them potential candidate genes for molecular markers of thermotolerance. This review highlights the associations of SNPs within these genes with thermotolerance traits (e.g., blood biochemistry and physiological responses) and suggests their potential use as MAS in thermotolerant cattle breeding.

• International Journal of Industrial Entomology and Biomaterials
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• v.31 no.2
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• pp.115-126
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• 2015

The tropical climate prevailing in India adversely affects temperate bivoltine silkworm rearing and causes crop loss especially during summer. Identification of high temperature tolerant bivoltine breeds by screening for thermotolerance in the silkworm, Bombyx mori (Lepidoptera: Bombycidae) is an essential prerequisite for the development of thermotolerant bivoltine breeds / hybrids. Therefore, in this study, 20 silkworm breeds were reared at different temperatures (25 ± 1℃,32 ± 1℃, 34 ± 1℃ and 36 ± 1℃) for 6 h every day from 3^rd d of 5^th instar to till spinning. Significant differences (p < 0.01) were found among all the rearing traits over temperature. Based on pupation percentage, SK4C and BHR3 were identified as thermotolerant bivoltine breeds. Hierarchical clustering analysis based on rearing traits at tested temperatures grouped 20 silkworm breeds in four clusters which included one cluster each of susceptible and tolerant, and two clusters of moderately tolerant silkworm breeds. This suggests that clustering based on rearing data at high temperatures by using Euclidean distance can be an effective approach in classifying the silkworm breeds on their thermotolerance capacity. The identified breeds would be used for development of thermo tolerant bivoltine silkworm breeds / hybrids.

• Journal of Ecology and Environment
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• v.32 no.3
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• pp.167-176
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• 2009

Land cover changes associated with urbanization have driven climate change and pollution, which alter properties of ecosystems at local, regional, and continental scales. Thus, the relationships among urban ecological variables such as community composition, structure, health, soil and functioning need to be better understood to restore and improve urban ecosystems. In this study, we discuss urban ecosystem management and research from a futuristic perspective based on analyses of vegetation structure, composition, and successional trends, as well as the chemical properties of soils and the distribution of heat along an urban-rural gradient. Urban thermo-profile analysis using satellite images showed an obvious mitigating effect of vegetation on the Seoul heat island. Community attributes of Quercus mongolica stands reflected the effects of urbanization, such as pronounced increases in disturbance-related and pollution-tolerant species, such as Styrax japonica and Sorbus alnifolia. Retrogressive successional trends were detected in urban sites relative to those in rural sites. Changes in the urban climate and biotic environment have the potential to significantly influence the practice and outcomes of ecological management, restoration and forecasting because of the associated changes in future bio-physical settings. Thus, for management (i.e., creation and restoration) of urban green spaces, forward-thinking perspectives supported by historical information are necessary.

• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.248-255
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• 2022

Phlebia sp. MG-60 is the salt-tolerant, white-rot fungus which was isolated from a mangrove forest. This fungus expresses three kinds of manganese peroxidase (MGMnP) isozymes, MGMnP1, MGMnP2 and MGMnP3 in low nitrogen medium (LNM) or LNM containing NaCl. To date, there have been no reports on the biochemical salt-tolerance of these MnP isozymes due to the difficulty of purification. In present study, we established forced expression transformants of these three types of MnP isozymes. In addition, the fact that this fungus hardly produces native MnP in a high-nitrogen medium (HNM) was used to perform isozyme-selective expression and simple purification in HNM. The resulting MGMnPs showed high tolerance for NaCl compared with the MnP of Phanerochaete chrysosporium. It was worth noting that high concentration of NaCl (over 200 mM to 1200 mM) can enhance the activity of MGMnP1. Additionally, MGMnP1 showed relatively high thermo tolerance compared with other isozymes. MGMnPs may have evolved to adapt to chloride-rich environments, mangrove forest.

• Journal of Microbiology and Biotechnology
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• v.1 no.3
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• pp.207-211
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• 1991

Yeast fermentation at $40^{\circ}C$ was conducted for microbial protein production and COD reduction in three different sugar beet stiIlages by a thermo- and acid-tolerant yeast Candida rugosa isolated from East Africa. The assimilation proceedings of some main components such as protein, carbohydrate, total titrable acids and glycerol in stillages were observed with growth kinetics of the yeast. Most of glycerol and organic acids were rapidly assimilated at the beginning of the fermentation. Protein assimilation was slowly accelerated with the proceeding of fermentation time and its assimilation rate reached only 14.2%-28.4%. Though Candida rugosa was a flocculent yeast, the flocculation characteristics of the yeasts grown in three stillages were different from each other.

• Microbiology and Biotechnology Letters
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• v.27 no.5
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• pp.364-369
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• 1999

In order to obtain the suitable plasmids for constructing plasmid vectors of Bacillus species, endogeneous plasmid DNAs were screended from thermo-tolerant soil bacteria. Based on agarose gel electrophoresis patterns of the isolated plasmid DNAs, two strains harboring small-size plasmids were selected. The isolated were identified to belong to the genus Bacillus on the basis of their morphological and biochemical properties, and named Bacillus sp. 3-3 and 77-8, respectively. The restriction endonuclease maps were determined for four plasmids including two plasmids from each Bacillus isolates. It is interesting that Bacillus sp. 3-3 and 77-8 have an identical plasmid according to the restriction maps. The three kinds of hybrid plasmids constructed by introducing each plasmid of two isolates into a Escherichia coli plasmid vector. pUCCm18 containing chloramplenicol resistance gene active in Bacillus strains, could be replicated in B. subtilis and B. licheniformis. These plasmids are very stable in B. subtilis, suggesting that the Bacillus plasmids identified in this work would be useful for development of new cloning vectors for Bacillus strains.