Antimicrobial activity of Securinega leucopyrus

Extracts of the leaves of Securinega leucopyrus exhibited a broad spectrum of antimicrobial activity.     

孟加拉涝原地区村林居住的宗教社团偏爱的乔木和灌木树种及使用的造林材料研究

2002年1月至6月对孟加拉涝原地区两个不同的宗教部落(印度教和穆斯林教)的传统家园森林进行了探索性研究，包括印度教和穆斯林教社团对树种(乔木和灌木)的偏爱度、类似性、造林材料及来源、植树地点和间距。研究发现Mangifera indica作为乔木树种，Ocimum sanctum作为灌木树种为印度教社团最喜爱的树种；Artocarpus heterophyllus和Lawsonia inermis分别为穆斯林社团最喜爱乔木树种和灌木树种。两中不同宗教社团选择乔木数种的相同性为86．57％，灌木树种为78．48％。两个宗教部落使用种子和苗木作为造林材料最多。乔木树种的造林材料主要来自家园(39％)灌木树种主要来自自然界(40％)。表3参27。     

棕榈在孟加拉乡村传统利用——一种可持续的生物多样性管理手段(英文)

采用多级采样的方法研究了孟加拉国农村耕作区内棕榈树的传统利用模式和当地的管理经验。农民管理棕榈主要为获取树液产品,生产以糖为主的次生品。树液可直接用作饮料,也可加工成糖蜜或酒精饮料。7块不同地块为棕榈提供生长环境,20.40%的棕榈种植在果园内。尽管中等级的农民拥有多数棕榈(33%),但是主要管理棕榈的是没有土地的农民,他们靠棕榈维持生计。这些农民将自己的智慧应用到棕榈管理当中,从种植到开孔取树液再到产品加工。如果能更科学地管理棕榈,加上农民的智慧,棕榈业将会对当地经济发展起到重要作用,也会丰富当地生物多样性。     

The locus for resistance to Asian soybean rust in PI 587855

Asian soybean rust (ASR) caused by Phakopsora pachyrhizi is one of the most serious soybean (Glycine max) diseases in tropical and subtropical areas. A soybean line, PI 587855, showed a resistance phenotype against ASR pathogens in Japan and South America at high frequency; however, little is known of the genetic control of this resistance and chromosomal location of the corresponding locus. Therefore, the aim of this study was to study the inheritance of PI 587855 resistance and map the corresponding locus with SSR markers aiming to use the linked markers in marker‐assisted selection. In the segregating population, resistance to ASR appeared to be controlled by a single dominant gene. The ASR resistance locus was mapped near to the chromosomal region where the resistant loci, Rpp1 and Rpp1‐b, were previously mapped. Comparative genetic mapping and disease reaction profiles of other seven lines carrying Rpp1 or Rpp1‐b to four Brazilian ASR isolates revealed that the resistance reaction exhibited by PI 587855 was similar to that of Rpp1‐b‐carrying varieties which have useful resistance to South American ASR strains.     

Marker-assisted selection of low erucic acid quantity in short duration Brassica rapa

Low erucic acid (LEA) rapeseed, which has accumulated mutant fatty acid elongase genes at the BnFAE1.1 and BnFAE1.2 loci of the A- and C-genome, respectively, is an important oilseed crop. Short growing turnip rape (B. rapa) is also important as a catch crop in the continuous cropping of rice in Asia but there is no LEA B. rapa cultivar for cultivation in South Asia. In order to develop LEA turnip rape cultivars, high erucic acid turnip rape cultivars were interspecifically crossed as recurrent parents to a canola quality rapeseed. In the meantime, we monitored incorporation of the mutant bnfae1.1 (e1) gene into A-genome of turnip rape, using a dCAPS primer pair, which can amplify PCR fragment only for the mutant e1 gene from A-genome. The early backcross progenies showed poor seed set, but which was improved in advanced progenies. Finally, homozygous e1e1 genotypes were established in the selfed progenies of BC₂–BC₃, and their LEA content was confirmed by gas-chromatography analysis. Our results and promising lines will contribute to LEA-trait selection in turnip rape and rapeseed breeding.     

Association mapping reveals loci associated with multiple traits that affect grain yield and adaptation in soft winter wheat

Genome-wide association studies (GWAS) are useful to facilitate crop improvement via enhanced knowledge of marker-trait associations (MTA). A GWAS for grain yield (GY), yield components, and agronomic traits was conducted using a diverse panel of 239 soft red winter wheat (Triticum aestivum) genotypes evaluated across two growing seasons and eight site-years. Analysis of variance showed significant environment, genotype, and genotype-by-environment effects for GY and yield components. Narrow sense heritability of GY (h ²  = 0.48) was moderate compared to other traits including plant height (h ²  = 0.81) and kernel weight (h ²  = 0.77). There were 112 significant MTA (p < 0.0005) detected for eight measured traits using compressed mixed linear models and 5715 single nucleotide polymorphism markers. MTA for GY and agronomic traits coincided with previously reported QTL for winter and spring wheat. Highly significant MTA for GY showed an overall negative allelic effect for the minor allele, indicating selection against these alleles by breeders. Markers associated with multiple traits observed on chromosomes 1A, 2D, 3B, and 4B with positive minor effects serve as potential targets for marker assisted breeding to select for improvement of GY and related traits. Following marker validation, these multi-trait loci have the potential to be utilized for MAS to improve GY and adaptation of soft red winter wheat.     

Quantification and Understanding of Above and Belowground Biomass in Medium Saline Zone of the Sundarbans,Bangladesh: The Relationships with Forest Attributes

ABSTRACT

The relationship between stand attributes and biomass accumulation pattern in a mangrove forest has been intensively studied in this study. We assessed above (AGM) and belowground mass (BGM) and examined the relationship between forest attributes and aboveground mass in the Sundarbans, Bangladesh. The study was conducted with 18 plots having total area of 1.08 ha. The mean AGM and BGM of the study sites were 234.08 and 132.85 Mg ha^?1 respectively. H. fomes contributed the highest amount (82.9% of total AGM and 80.53% of total BGM) of above (193.56 Mg ha^?1) and belowground mass (107.09 Mg ha^?1) at the study site. Our study revealed structural attributes (tree diameter, height, and basal area) positively correlated with AGM. In contrast, species richness and species diversity negatively correlated with AGM. Our study indicated that lack of positive relationship between species diversity and AGM which may be attributable to high AGM of the dominant species (H. fomes) and may have a considerable consequence in AGM of the study area. Thus, maintaining large trees (DBH and height) rather than species diversity in the Sundarbans mangrove forest might be an effective approach for increasing aboveground mass.     

孟加拉吉大港地区乡村家庭竹手工业

对孟加拉吉大港地区家庭竹子手工业非农就业的潜力以及对其产生的社会经济效益进行了调查。本地区有40个竹企业,涉及到Hathazcori upazila的4个村庄。80%手工业者的年龄在30~50岁。他们的大多数是未受教育和土地贫瘠的家庭成员。50%的企业是由夫妻或3~5个工人组成的。竹产品主要是满足当地市场的需求。产品是根据季节的变化而决定的。5个产品中,竹书架提供了企业月净收入的41%,平均月净利润约2373.48塔卡,这为促进乡村经济发展起到重要的作用。作者对竹产业发展的状况进行了验证,并提出了建议。     

Rooting behavior of rice cultivars under different planting methods

An experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh in Old Brahmaputra Alluvial Flood Plain (AEZ-9) during December 2005 to May 2006 to examine the root growth of different rice cultivars under various establishment methods. This experiment comprised two sets of treatment (i) three methods of planting viz., dry direct seeding, wet direct seeding and transplanting, and (ii) six rice cultivars, two inbreds viz., BRRI Dhan 28 and BRRI Dhan 29, two hybrids, viz., Aalok 6201 and Sonarbangla 1 and two local improved cultivar viz., Habigonj IV and Habigonj VIII. Cultivars had more remarkable effect on different root parameters i.e. number of roots, root length, root length density, root biomass, root weight ratio and root shoot ratio of hybrid, inbred and local improved rice cultivars than method of planting. BRRI Dhan 28 performed the best for most of the parameters. At harvest, BRRI Dhan 29 showed the best rooting behavior among the cultivars. For both stages hybrid rice cultivars showed intermediate and local improved cultivars performed lower in rooting behavior. Direct seeding method performed better than transplanting method for most of the root parameters but wet direct seeding and dry direct seeding methods were identical. Interaction effect between method of planting and cultivar in most of the root parameters were insignificant. But, BRRI Dhan 28 and BRRI Dhan 29 under wet direct seeding method and Sonarbanngla 1 under transplanting method showed the best rooting performance among the other combinations.     

Exogenous Calcium Supplementation Improves Salinity Tolerance in BRRI Dhan28; a Salt-Susceptible High-Yielding Oryza Sativa Cultivar

Journal of Crop Science and Biotechnology - Salinity is one of the most brutal abiotic stressors, commencing a great stumbling block in the way of attaining food security in Bangladesh. Cultivation...