Method for screening bread wheat for tolerance to boron

A new method for screening wheat for boron tolerance has been developed to overcome the problems of methods used in the past. Seedlings were grown for 10 days while suspended over B-rich solutions. Their root lengths were then measured as an index of tolerance. Five varieties of wheat were screened at seven concentrations of B. Results were obtained more quickly and easily than from the alternative methodologies and compared favourably. Screening of 128 doubled haploid lines from a cross between Halberd and (Wl*MMC) suggested that transgressive segregation had occurred. This revised version was published online in August 2006 with corrections to the Cover Date.     

Efficacy of using previously used controlled internal drug release (CIDR) insert on the reproductive performance,hormone profiles and economic measures of sheep

This study was conducted using 120 multiparous Awassi ewes during the breeding season to compare the effects of using previously used controlled internal drug release (CIDR) on the hormone profiles, reproductive performance and economic measures of ewes. Ewes were randomized to receive one of five previously used CIDR (previously used for 6, 12, 18, 24 or 30 days) or the new CIDR as a control for 6 days (CIDR6, CIDR12, CIDR18, CIDR24, CIDR30, and CIDR0 [control], respectively). Blood samples were collected on four occasions, at the time of CIDR insertion, after 3 days of insertion, and at the time of withdrawal and insemination. Serum estradiol (E2) and progesterone (P4) concentrations were measured. Timed insemination was performed 48 hr post‐CIDR withdrawal. Pregnancy was diagnosed by ultrasonography 23 days after insemination and confirmed on day 35. The heat detection rate was significantly (p < 0.05) higher in the CIDR0 and CIDR6 groups than in the CIDR18 and CIDR30 groups. The total pregnancy rate and fecundity were significantly (p < 0.05) higher in the CIDR6 group than in other groups. P4 level was significantly (p < 0.05) higher in the CIDR0 group than in the CIDR30 group at the time of removal. At each time point, the E2 level was significantly (p < 0.05) higher in the CIDR6 group than at the other groups. The total variable cost, total cost, return and net profit were higher in the CIDR6 and CIDR0 groups than in the other groups. In conclusion, although previously used CIDRs are efficient at synchronizing oestrus in ewes, the duration of previously usage significantly affected the reproductive parameters and economic profit. CIDRs previously used for 6 days and new CIDRs provided the highest fertility and fecundity rates, besides return and net profit. Economically, it is not advisable to use CIDRs that previously used for 12 days or more.     

Rice straw biochar amended soil improves wheat productivity and accumulated phosphorus in grain

Abstract

Biochar is a pyrolyzed biomass produced under limited oxygen or oxygen absent conditions. Few investigations have been conducted to determine the combined effect of biochar with chemical fertilizer on growth, yield and nutrient distribution pattern in root, shoot and grain in wheat as well as changes in soil physiochemical properties. This research was designed to study the combined effect of chemical fertilizer and rice straw-derived biochar on soil physio-chemical properties, growth, yield and nutrient distribution pattern within wheat plant tissue and grain. Results showed that rice straw biochar caused a significant decrease in soil pH and increase in soil organic matter as well as nutrients like total nitrogen (TN), potassium (K), magnesium (Mg) and boron (B) due to incubation. Result also showed that root biomass and straw did not differ between Bangladesh Agricultural Research Council (BARC) and ½ BARC?+?rice straw biochar treatment. Similarly, thousand grain weight and grain yield did not differ between the same treatments. The phosphorus concentration in wheat grain was highest in ½ BARC?+?rice straw biochar as compared to other treatments. The use of rice straw biochar in addition to the chemical fertilizers in wheat production systems is an economically feasible and practical nutrient management practice. Our findings urged that reduction of chemical fertilizer application is possible with supplementation of rice straw biochar.     

Effect of organic and inorganic selenium supplementation on semen quality and blood enzymes in buffalo bulls

The present study aimed to evaluate the effect of organic and inorganic selenium (Se) supplementation on semen quality and blood serum profiles of buffalo bulls. Nine mature buffalo bulls were divided into three groups: control (non‐supplemented); organic Se (10 mg Sel‐Plex®/head twice weekly) and inorganic Se (10 mg sodium selenite/head twice weekly). Semen was collected twice a week for 3 months during Se supplementation. Semen properties were evaluated from fresh ejaculate. Moreover, fructose concentration, aspartate and alanine transaminase (AST and ALT) activities, total protein and total cholesterol were assayed in seminal plasma. Additionally AST, ALT, testosterone and Se levels were determined in the blood serum. Results showed that Se supplementation significantly (P < 0.05) influences the semen parameters during 3 months of treatment. Organic Se significantly (P < 0.05) increased the percentage of viable sperms compared to inorganic Se and the control group. Fructose concentration was significantly higher (P < 0.05) in the seminal plasma of organic Se‐treated bulls. Serum testosterone and Se concentrations were significantly (P < 0.05) increased in the Se supplemented groups than the control group. In conclusion, Se supplementation improved the parameters of buffalo bull semen and more precisely, organic Se was more effective for the improvement of semen quality and some blood components than inorganic Se.     

Antimicrobial and cytotoxic constituents of Loranthus globosus

(+)-Catechin, 3,4-dimethoxycinnamyl alcohol and 3,4,5-trimethoxycinnamyl alcohol were isolated from the barks of Loranthus globosus. All compounds showed significant antimicrobial and cytotoxic activities.     

树木-水稻农林系统中害虫的侵害

本文比较研究了10种水稻害虫在3个树种(Akashmoni,Jhau和Albida)与稻子混栽的农-林复合生态系统中的发生情况,通过3个树种的冠幅大小、透光率以及害虫发生程度相比较,提出农-林复合生态系统中,水稻害虫的发生与树冠的透光率呈密切的负相关关系。     

Role of homestead forests in household economy and factors affecting forest production: a case study in southwest Bangladesh

Empirical information regarding the role of homestead forests in household economy is essential in understanding the importance of these resources. Identification of the factors that affect homestead forest production and understanding forest owners' attitudes toward key forest management issues have great significance in making appropriate policy responses to manage these resources on a sustainable basis. In Bangladesh, homestead forests are claimed to play an important economic role in rural livelihoods, but no reliable quantitative information exists. This study was undertaken to investigate the role of homestead forests in the household economy, examine if forest production and income vary across landholding size classes, to explore the relationships of homestead forest production with species richness, education level, and household size, and to assess the attitude of homestead forest owners toward key forest management issues. Results show that homestead forests contribute 15.9% of the household income and generate 51.4 man-days of employment per household per year. Production of homestead forests significantly varies across landholding size classes. It was observed that forest production depends significantly on species richness of homestead forests and the education level of forest owners. However, no such relationship was found between forest production and household size. The study revealed that farming families depend more on forest income than nonfarming families. Attitudes of forest owners toward key forest management issues differ significantly across landholding size classes. For example, although the majority of the forest owners prefer fruit species to timber species, the percentage of respondents decreased as the landholding size class increased, while the opposite trend was observed for timber species. The findings of this study suggest that diversification of forests and extension of education amongst forest owners would improve forest production. Furthermore, forest policy should address the concerns of the forest owners in different landholding classes and focus on their specific requirements to enhance sustainable forest management.     

Economic contribution of participatory agroforestry program to poverty alleviation: a case from Sal forests, Bangladesh

In the Forest Department of Bangladesh, a Participatory Agroforestry Program (PAP) was initiated at a denuded Sal forests area to protect the forest resources and to alleviate poverty amongst the local poor population. We explored whether the PAP reduced poverty and what factors might be responsible for poverty alleviation. We used three poverty measurement methods: the Head Count Index, the Poverty Gap Index and the Foster-Greer-Thorbecke index to determine the extent poverty reduction. We used a linear regression model to determine the possible differences among factors in poverty reduction. Data were collected through semi-structured questionnaires and face to face interviews within the study area. PAP proved effective at poverty alleviation, considerably improving the local situation. The linear regression model showed that PAP output explained the income differences in poverty reduction. Participants identified bureaucracy and illegal money demands by forest department officials, an uncontrolled market system, and underdeveloped road infrastructure as the main obstacles to reduction of poverty. Overall, PAP is quite successful in alleviating poverty. So this program might be ofinterest at other degraded forest areas as a tool to alleviate poverty.     

Non-escaping frost tolerant QTL linked genetic loci at reproductive stage in six wheat DH populations

Reproductive stage frost poses a major constraint for wheat production in countries such as Australia.However,little progress has been made in identifying key genes to overcome the constraint.In the present study,a severe frost event hit two large-scale field trials consisting of six doubled haploid(DH)wheat populations at reproductive stage(young microspore stage)in Western Australia,leading to the identification of 30 robust frost QTL on 17 chromosomes.The major 18 QTL with the phenotype variation over 9.5%were located on 13 chromosomes including 2 A,2 B,2 D,3 A,4 A,4 B,4 D,5 A,5 D,6 D,7 A,7 B and7 D.Most frost QTL were closely linked to the QTL of anthesis,maturity,Zadok stages as well as linked to anthesis related genes.Out of those,six QTL were repetitively detected on the homologous regions on 2 B,4 B,4 D,5 A,5 D,7 A in more than two populations.Results showed that the frost damage is associated with alleles of Vrn-A1 a,Vrn-D1 a,Rht-B1 b,Rht-D1 b,and the high copy number of Ppd-B1.However,anthesis QTL and anthesis related genes of Vrn-B1 a and Ta FT3-1 B on chromosomes 5 B and 1 B did not lead to frost damage,indicating that these early-flowering phenotype related genes are compatible with frost tolerance and thus can be utilised in breeding.Our results also indicate that wild-type alleles Rht-B1 a and Rht-D1 a can be used when breeding for frost-tolerant varieties without delaying flowering time.     

Production and economic return of shrimp aquaculture in coastal ponds of different sizes and with different management regimes

Coastal shrimp (Penaeus monodon) aquaculture in Bangladesh is mostly practiced in a special type of field/pond situated by the side of a river -- called a Gher -- that is used to cultivate rice in winter and shrimp in summer. Ghers of different sizes are managed in different ways. In order to understand the effects of Gher size and their corresponding management practices on the production and economic returns of shrimp farming, we conducted an on-farm study in three small (1–5 ha), three medium (6–10 ha) and three large (>10 ha) Ghers located in the coastal Southwest region of Bangladesh. The mean harvest weight of shrimp was similar in all Ghers, but survival rates were higher in the small (50%) and medium (37%) ones than in the large (18%) ones. The high mortality in the large units led to a production that was lower than one-half of that in the small Ghers (about 80 and 200 kg/ha, respectively). The total variable costs per unit area were similar in all Ghers, but the importance of different items varied with Gher size. In the small Ghers, there are relatively high investments on inputs and labor. This expenditure results in lower shrimp mortality and higher production, which in turn results in gross returns that are larger than the total costs -- hence, a positive and high net return. In large Ghers, the fixed costs are larger than in the small ones simply because of the size of the pond. Variable costs include higher investments in post-larvae and labor than in small Ghers, and lower inputs applied only at pond preparation. This results in higher shrimp mortality and lower production, which in turn results in gross returns that are smaller than the total costs -- hence, a negative or low net return. These findings have positive implications for the future policy formulation of coastal shrimp aquaculture in Bangladesh.