Zhang H.,Chinese Academy of Agricultural Sciences |
Uddin M.S.,Chinese Academy of Agricultural Sciences |
Uddin M.S.,Bangladesh Agricultural Research Institute BARI |
Zou C.,Chinese Academy of Agricultural Sciences |
And 4 more authors.
Journal of Integrative Plant Biology | Year: 2014
Plants with tolerance to low-phosphorus (P) can grow better under low-P conditions, and understanding of genetic mechanisms of low-P tolerance can not only facilitate identifying relevant genes but also help to develop low-P tolerant cultivars. QTL meta-analysis was conducted after a comprehensive review of the reports on QTL mapping for low-P tolerance-related traits in maize. Meta-analysis produced 23 consensus QTL (cQTL), 17 of which located in similar chromosome regions to those previously reported to influence root traits. Meanwhile, candidate gene mining yielded 215 genes, 22 of which located in the cQTL regions. These 22 genes are homologous to 14 functionally characterized genes that were found to participate in plant low-P tolerance, including genes encoding miR399s, Pi transporters and purple acid phosphatases. Four cQTL loci (cQTL2-1, cQTL5-3, cQTL6-2, and cQTL10-2) may play important roles for low-P tolerance because each contains more original QTL and has better consistency across previous reports. © 2014 Institute of Botany, Chinese Academy of Sciences.
Rahman S.,University of Plymouth |
Hasan M.K.,Bangladesh Agricultural Research Institute BARI
Energy | Year: 2014
Wheat is the second most important cereal crop in Bangladesh and production is highly sensitive to variations in the environment. We estimate productivity and energy efficiency of wheat farming in Bangladesh by applying a stochastic production frontier approach while accounting for the environmental constraints affecting production. Wheat farming is energy efficient with a net energy balance of 20,596MJ per ha and energy ratio of 2.34. Environmental constraints such as a combination of unsuitable land, weed and pest attack, bad weather, planting delay and infertile soils significantly reduce wheat production and its energy efficiency. Environmental constraints account for a mean energy efficiency of 3 percentage points. Mean technical efficiency is 88% thereby indicating that elimination of inefficiencies can increase wheat energy output by 12%. Farmers' education, access to agricultural information and training in wheat production significantly improves efficiency, whereas events such as a delay in planting and first fertilization significantly reduce it. Policy recommendations include development of varieties that are resistant to environmental constraints and suitable for marginal areas; improvement of wheat farming practices; and investments in education and training of farmers as well as dissemination of information. © 2014 Elsevier Ltd.
Matin M.A.,University of South Australia |
Matin M.A.,Bangladesh Agricultural Research Institute BARI |
Fielke J.M.,University of South Australia |
Desbiolles J.M.A.,University of South Australia
Biosystems Engineering | Year: 2014
Two-wheeled tractors fitted with rotary cultivators are used in many developing countries for full disturbance soil tillage. Recent development, motivated by the benefits of conservation agriculture, is working toward strip-tillage seeding using two-wheeled tractors fitted with modified rotary cultivators and seeding attachments. The effect of three blade geometries (conventional, half-width and straight) at four rotary speeds (125, 250, 375, and 500rpm) on the furrow seedbed parameters when used for strip-tillage was investigated. The experimental blades were mounted on a rotary tiller test unit operating in a reconstituted sandy loam soil travelling at a forward speed of 0.67ms-1. Analysis of the high-speed video showed that the straight blade reduced the soil carrying and throwing. At 125rpm all blades produced either an unsatisfactory cloddy seedbed with an irregular furrow bottom and walls or an incomplete furrow. At 500rpm, considerable amounts of soil were thrown out of the furrow for the conventional and half-width blades which achieved furrow backfills of only 41 and 36%, respectively. The straight blade achieved the fullest backfill at 74% even when operating at 500rpm. The level of soil pulverisation increased with rotary speed, but was not affected by blade geometry. Each of the blades produced different furrow shapes with a higher furrow volume tilled by the conventional and the straight blades compared to that by the half-width blades. Based on its high backfill and large furrow volume, the straight blade would be the preferred option when undertaking rotary strip-tillage. © 2013.
Rahman S.,University of Plymouth |
Rahman M.S.,Bangladesh Agricultural Research Institute BARI
Energy | Year: 2013
The paper evaluates sustainability of maize cultivation in Bangladesh in terms of energy use while taking into account factors affecting choice of the growing season and farmers' production environment using a sample selection framework applied to stochastic frontier models. Results reveal that the probability of growing winter maize is influenced positively by gross return, irrigation, subsistence pressure, soil suitability and temperature variability whereas extension contact influences choice negatively. Significant differences exist between winter and summer maize regarding yield, specific energy, net energy balance, energy use efficiency and technical energy efficiency although both systems are highly sustainable and efficient. The energy output from winter maize is 199,585 MJ/ha which is 53.9% higher than the summer maize output of 129,701 MJ/ha. Also, energy input use of winter maize is 110.6% higher than the summer maize. Energy inputs from mechanical power, seeds, fertilizers and organic manures significantly increase energy productivity of winter maize whereas only mechanical power influences summer maize productivity. However, temperature variation and rainfall significantly reduce energy productivity of summer maize. Policy implications include investments in soil conservation and irrigation, development of weather resistant varieties and raising maize price will boost maize cultivation in Bangladesh, a highly sustainable production technology. © 2012 Elsevier Ltd.
Latif M.A.,University Putra Malaysia |
Latif M.A.,Bangladesh Rice Research Institute BRRI |
Rahman M.M.,Bangladesh Agricultural Research Institute BARI |
Ali M.E.,University of Malaya |
And 2 more authors.
Comptes Rendus - Biologies | Year: 2013
Multivariate analyses were performed using 13 morphological traits and 13 molecular markers (10 SSRs and three ISSRs) to assess the phylogenetic relationship among tungro resistant genotypes. For morphological traits, the genotypes were grouped into six clusters, according to D2 statistic and Canonical vector analysis. Plant height, days to flowering, days to maturity, panicle length, number of spikelet per panicle, number of unfilled grain per panicle and yield were important contributors to genetic divergence in 14 rice genotypes. Based on Nei's genetic distance for molecular studies, seven clusters were formed among the tungro resistant and susceptible genotypes. Mantel's test revealed a significant correlation (r = 0.834*) between the morphological and molecular data. To develop high yielding tungro resistant varieties based on both morphological and molecular analyses, crosses could be made with susceptible (BR10 and BR11) genotypes with low yielding but highly resistant genotypes, Sonahidemota, Kumragoir, Nakuchimota, Khaiyamota, Khairymota and Kachamota. The chi-square analysis for seven alleles (RM11, RM17, RM20, RM23, RM80, RM108 and RM531) of SSR and five loci (RY1, MR1, MR2, MR4 and GF5) of three ISSR markers in F2 population of cross, BR11 × Sonahidemota, showed a good fit to the expected segregation ratio (1:2:1) for a single gene model. © 2013 Académie des sciences.