A comparative study of mangrove ? oras in China and India

Species compositions in the mangrove habitats of China and India, especially on Hainan Island (China) and on the Sundarbans and the Andaman & Nicobar Islands (India), are of interest, showing several similarities and differences. The total mangrove areas of India cover about 6419 km 2 with 43 species (23 major and 20 minor species), while the mangrove areas of China cover about 150 km 2 with 26 speices (19 major and 7 minor speices). We carried out a comparison of mangrove floras in the Indian Sundarbans, Andaman & Nicobar Islands and in Hainan Island. The mangrove areas of the Indian Sundarbans comprise about 66.5% of the total Indian mangroves, presently covering an area of 4267 km 2 with 35 species from 22 genera and 16 families. There are 34 species from 17 genera and 13 families in the Andaman & Nicobar Islands. Hainan Island is considered a distribution center of mangroves; it has the largest number of mangrove species in China, i.e., 25 species from 15 genera and 12 families, accounting for about 96% of the total number of mangrove species in China. The mangroves of Hainan Island and the Andaman & Nicobar Islands belong to island types, while those of Sundarbans belong to inter-tidal deltaic types. Differences in soil type, rainfall, temperature, tidal fluctuation and other climatic features possibly cause variations in floristic composition of these regions.     

Folklore medicinal plants of North Andaman Islands, India

The rural folk of North Andaman, India use the traditional medicine for their primary health care. Folklore medicinal uses of 72 interesting medicinal plant species along with botanical name, local name, family, habit, part used, disease for which the drug is administrated, mode of administration are presented. These 72 plant species which provide the crude drugs pertain to 67 genera and 43 families of Magnoliophyta from tropical rainforests. These plants used to cure 40 ailments. Most remedies were taken orally, accounting for 76% of medicinal use. Most of the remedies were reported to have been from trees (55.6%) and herb (22.2%) species. The most widely sought after plant parts in the preparation of remedies in the areas are the stem bark (33.8%) and root (23.9%).     

Thraustochytrids of Mangrove Habitats from Andaman Islands: Species Diversity,PUFA Profiles and Biotechnological Potential

Thraustochytrids are the most promising microbial source for the commercial production of docosahexaenoic acid (DHA) for its application in the human health, aquaculture, and nutraceutical sectors. The present study isolated 127 thraustochytrid strains from mangrove habitats of the south Andaman Islands, India to study their diversity, polyunsaturated fatty acids (PUFAs), and biotechnological potential. The predominant strains were identified as belonging to two major genera (Thraustochytrium, Aurantiochytrium) based on morphological and molecular characteristics. The strain ANVKK-06 produced the maximum biomass of 5.42 g·L⁻¹, while ANVKK-03 exhibited the maximum total lipid (71.03%). Omega-3 PUFAs such as eicosapentaenoic acid (EPA) accumulated up to 11.03% in ANVKK-04, docosapentaenoic acid (DPA) up to 8.65% in ANVKK-07, and DHA up to 47.19% in ANVKK-06. ANVKK-06 showed the maximum scavenging activity (84.79 ± 2.30%) while ANVKK-03 and ANVKK-10 displayed the highest antibacterial activity against human and fish pathogens, S. aureus (18.69 ± 1.2 mm) and V. parahaemolyticus (18.31 ± 1.0 mm), respectively. All strains were non-toxic as evident by negative blood agar hemolysis, thus, the thraustochytrids are suggested to be a potential source of DHA for application in the health care of human and fish.     

Changing trend in the seroprevalence and risk factors of human leptospirosis in the South Andaman Island,India

Seroprevalence of leptospirosis among a healthy population of the South Andaman Island was assessed through random sampling. Previous studies have high seroprevalences of up to 55% in general population and 65% in agricultural labourers. The study subjects (1,181 in total, 781 rural and 400 urban) were interviewed and tested for antibodies against Leptospira. Multivariate models were developed to determine the risk factors in the rural and the urban population. The overall seroprevalence was 10.9%, with rural (12.9%) being higher than the urban subjects (7.0%). The commonest infecting serogroup was Icterohaemorrhagiae (53.5%), followed by Grippotyphosa (13.2%). Compared to the earlier observation, seroprevalence was lower and an apparent shift in the infecting serogroup was found. This shift was in concordance with the changing trend in animal population. Significant difference in risk factors, both in rural and urban areas, was also observed. Similar trends in seroprevalence are being observed around the world. Therefore, time to time prevalence studies are needed for the development of effective control measure.     

缅甸安达曼海浅色黄姑鱼生物学特性的初步研究

2012年10月—2013年1月在缅甸安达曼海域探捕期间,根据随机选取的650尾浅色黄姑鱼Nibea coibor样本生物学数据,对该鱼种的生物学特性进行了分析。结果表明:浅色黄姑鱼全长为138～459 mm,平均全长为243 mm,体长为109～381 mm,平均体长为200 mm,体质量为25～868 g,平均体质量为214g;全长(TL)与体长(BL)的关系式为TL=0.8626BL-8.4845(R2=0.9536),雌、雄个体间全长和体长分布均无显著性差异(P>0.05);体质量(BW)与体长(BL)的关系式为BW=0.0001BL2.713(R2=0.9159);雌性与雄性之比为1.19∶1,性成熟度以Ⅱ期和Ⅲ期为主;摄食等级以2、3级为主,占总样本数的69.69%,摄食等级为1～4的个体平均体长间无显著性差异(P>0.05)。     

Collection of plant genetic resources from Andaman and Nicobar Islands

The Andaman and Nicobar (A&N) group of islands is immensely rich in plant biodiversity. Andaman’s native tribes are hunter-gatherers, sustaining on wild or marine food and practically do not have any cultivation. Diversity in cultivated crops is presently maintained in home gardens by settlers from the mainland and other adjoining countries. The National Bureau of Plant Genetic Resources (NBPGR) through explorations either alone or in association with CARI or with other ICAR institutes has collected 1234 accessions in 48 exploration and collection missions. Variability was collected in rice, cowpea, black gram, green gram, okra, Chinese spinach, ash gourd, taro, cucumber, pumpkin, bottle gourd, ridge gourd, bitter gourd, chilli, greater yam and coconut. Indigenous landraces are absent. The in situ conservation of the wild relatives of crops is well taken care of by a large number of protected forest reserves.     

IF THAI SHRIMP FARMING WERE TAXED,HOW MUCH SHOULD IT BE?

A dynamic-constraint optimization model that incorporates the accumulated nutrient load from farm discharges to the sea is applied to derive an optimal corrective tax for Thai shrimp farming. The model internalizes the environmental costs of the cumulated stock of nutrients discharged, mangrove conversion and abandoned farms. It suggests imposing a tax on the stock externality that is equal to the increasing shadow cost of the stock of nutrient accumulated before damage occurs. However, the simulation results show very small shadow costs at the beginning of the paths and indicate that the nutrient load has a negligible impact on the Andaman Sea but a significant effect on the Gulf of Thailand. A socially efficient level of production for Thailand would be around 70–80% of private optimal production. The tax ensures a higher net gain from trade. On the other hand, its effect on net social welfare is ambiguous.     

The host background of rice influences the resistance expression of a three genes pyramid (xa5 + xa13 + Xa21) to bacterial blight (Xanthomonas oryzae pv. oryzae) pathotypes of Indian mainland and Bay islands

Bacterial blight (BB) is a major disease of rice for which host resistance is the only effective solution. The three genes pyramid xa5 + xa13 + Xa21 is recently the most utilized combination for developing resistant varieties through marker‐assisted breeding. Our study was carried out to elicit the detailed response of twenty lines possessing these three genes in five genetic backgrounds to twelve diverse BB pathotypes in India. The lines developed from ADT 47 variety showed incomplete resistance to most of the pathotypes, whereas susceptibility varied from 8.3% to 16.6% in ADT 43 and IR24, respectively. However, in IMP ASD16/60 and Improved Samba Mahsuri, complete resistance against all pathotypes was observed. The overall results confirmed that genetic background plays crucial role for the effective expression of xa5 + xa13 + Xa21 combination. Molecular studies did not reveal correlation between origin of pathotypes and their virulence potential. It is suggested to deploy Improved Samba Mahsuri, IMP ASD 16/60 and AD1306 varieties in the bacterial blight prone areas or use them as donors for realizing wider and durable resistance.     

Aspects in spawning biology and migration of the mud crab Scylla olivacea in the Andaman Sea, Thailand

Abstract  Spawning biology and migration of the mud crab, Scylla olivacea (Herbst), in the Andaman Sea were examined from November 2002 to March 2004 at Klong Ngoa Mangrove area, Ranong Province, Thailand. Mature females were dominant from July to November. The changes in monthly gonadosomatic index of females ranged from 1.9 (±3.3) to 8.2 (±5.8) and size at first maturity was 9.4 cm internal carapace width (ICW). Fecundity ( F ) correlated ICW according to F =3.02 ×ICW^2.98. A total of 1013 female crabs were double tagged with spaghetti and bottom tags. The recaptured rate was 36.7% and showed that females migrated from coastal area to the open sea during the spawning season. A closed season during the north-east monsoon season and a minimum legal ICW size of 10 cm are recommended for sustainable management of the fishery.     

缅甸外海大西洋带鱼基础生物学特性初步研究

[目的]了解缅甸外海大西洋带鱼的基本生物学特性,为合理开发和利用该海域的渔业资源提供参考.[方法]根据2012年10月～2013年1月在缅甸外海定置网渔船探捕调查所收集的渔获资料,对主要渔获的大西洋带鱼（Trichiurus lepturus）生物学特性进行研究分析.[结果]大西洋带鱼的雌雄性别比1.1∶1.0;性成熟度以Ⅱ～Ⅳ期为主,占样本总数的94.35％;摄食等级不高,主要是1～2级,占样本总数的78.24％;肛长范围101～422 mm,均值为212.26 mm,优势肛长组为141～260mm,占个体总数的79.14％.按经、纬度来分析,发现在东经95°～96°30 ′范围内大西洋带鱼的平均肛长较短,而在北纬14°～15°30′范围内大西洋带鱼的平均肛长较长;雌性个体在优势肛长组（181～220mm）中出现的频率高于雄性.大西洋带鱼的优势体重组为51～200 g,占个体总数的63.94％,且雌性所占比例较雄性高.对大西洋带鱼的肛长与体重进行线性回归处理,发现雌性个体与雄性个体的生长模式基本相同,肛长与体重不存在显著相关性.[结论]缅甸外海大西洋带鱼的资源状况良好,捕捞生产仍可持续发展.