Comparison of methods for the estimation of best parent heterosis among lines developed from interspecific sunflower germplasm

Pre-breeding and elite breeding are two steps in creating high yielding sunflower hybrids that differ in well established procedures and selection methods. However, a methodology that bridge efficient use of introgression lines as product of pre-breeding procedures and their crossing to elite inbreed lines, is not yet very well established. Therefore, the development of cost- and time-efficient methods for the determination of best parent heterosis and the use of best inbred lines in crosses with introgression lines for obtaining high-yielding and stable hybrids is highly desirable. In this regard, sixteen Cytoplasmic Male Sterile (CMS) inbred lines (A) derived from four heterogeneous interspecific lines originating from three annual: H. debilis silvestris (DEB-SIL), H. praecox runyoni (PRA-RUN), H. deserticola (DES) and one perennial H. resinosus (RES) wild species were evaluated. Seven agronomic traits were measured over a period of 2 years and 38 DNA loci were analysed, in order to compare four different methods for the estimation of best parent heterosis (BPH). New inbred lines were characterized by Principal Component Analysis (PCA) of morphological traits and Principal Coordinate Analysis (PCoA) of molecular marker data. Line?×?tester mating design was used to evaluate General Combining Ability (GCA), while Genetic Distance (GC) estimated by markers was evaluated as a predictor of BPH by Locally Weighted Sequential Smoothing (LOESS). Analysis of combining ability is one of the most important tools breeders use to identify superior inbred lines on the basis of their performance in hybrid combinations. Results obtained in this research show that PCA of morphological and PCoA of molecular marker data on parental lines are generally in agreement with GCA effects for examined traits. GD versus BPH relationships indicate that intermediate to high GD between parental lines was optimal for best heterotic effects of most traits. In this study, we show that the combination of the PCA of morphological data, PCoA of molecular marker data and GD between parental lines is fast and affordable, giving the most important information for parental choice of introgression and elite lines in sunflower breeding programs.     

Synthesis,Characterization, and Use of Carbon Microspheres for Removal of Different Dyes from Aqueous Environments

Water, Air, & Soil Pollution - Sustainable groundwater quality has become a major concern for the agro-based country like Bangladesh. Integrated approaches of various irrigation water quality...     

Incorporation of rice straw mitigates CH4 and N2O emissions in water saving paddy fields of Central Vietnam

This study evaluated the effects of rice straw and water regimes on CH₄ and N₂O emissions from paddy fields for two rice growing seasons (summer 2014 and spring 2015). Water regimes included alternating wet–dry irrigation (AWD) maintained at three levels (–5 cm, – 10 cm and –15 cm) in comparison to continuous flooding irrigation (CF). Rice straw (5 t ha^–1) was incorporated into the top soil (0 – 15 cm), distributed and burned in situ. Results showed that using burned in situ rice straw was found to reduce seasonal cumulative CH₄ emission (24–34% in summer; 18–28% in spring), N₂O emission (21–32% in summer; 22–29% in spring) and lower rice yield (8–9%) than rice straw incorporation into top soil. AWD methods reduced the amount of CH₄ production (22.6–41.5%) and increased N₂O emission (25–26%) without any decrease in rice yield. Rice straw incorporation into the top soil with AWD had higher water productivity (23–37%) than rice straw when burned in situ with CF. The results conclude that AWD and rice straw management can be employed as mitigation strategy for CH₄ and N₂O emissions from paddy fields in Central Vietnam.     

Conservation status evaluation of <Emphasis Type="Italic">Berberis</Emphasis> species across the Karakoram Mountain Ranges,Pakistan using IUCN Red List Categories and Criteria

Berberis species are endangered, high-value medicinal plants in Pakistan with important eco-cultural, commercial and livelihood roles in mountain communities. To assess the geographical distribution of Berberis species across the Karakoram Mountain Ranges in Pakistan, we used IUCN Red List Categories and Criteria (2001) to calculate the extent of occurrence (EOO, <100 km²) and the area of occupancy (AOO, <10 km²) of Berberis pseudumbellata subsp. pseudumbellata and B. pseudumbellata subsp. gilgitica. Overgrazing and habitat loss were key population-limiting factors. The two subspecies had contrasting responses to temperature, elevation, precipitation and insect susceptibility. B. pseudumbellata subsp. gilgitica is endemic to Gilgit-Baltistan and grows in single-cropping zone (areas > 200 m a.s.l.). Status evaluation revealed that both subspecies meet the criteria set for critically endangered species. Prolonged disregard of its declining population trend might lead to its extinction; therefore, integrated conservation efforts are necessary.     

Multiple-criteria decision-making techniques and their role in livestock ration formulation

The livestock ration formulation problem is postulated within the framework of multiple-criteria decision-making techniques. This exercise is motivated by the fact that the ordinary least-cost approach can, and does, generate solutions that either cannot be implemented or supply nutritionally undesirable levels of various nutrients. This originates from using cost as the criterion for selecting the ingredients of the diet. But in fact, diet formulation problems involve several criteria and should, therefore, be solved using techniques designed for modelling such problems. This paper is an attempt at introducing these techniques to agricultural systems modellers and then demonstrating their use in livestock ration formulation. The multiple-criteria decision-making techniques covered include goal programming and its variants such as weighted and lexicographic approaches and multiple-objective programming.