Root volume as a grading criterion to improve field performance of Douglas-fir seedlings

Three seed sources of 2+0 Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] seedlings were graded into three root-volume categories (<9, 9–13, and >13 cm³) and outplanted to determine (i) differences in survival and growth after one and two growing seasons in the field, (ii) relationship(s) of seedling height after one and two seasons to preplanting nursery root volume, total fresh weight, root-collar diameter, and height, and (iii) differences in field performance due to fertilization at planting. Field survival was >90% among all root-volume categories. Seedlings in the largest category grew significantly better than those in the smaller two categories over two seasons. Apparently, a population of seedlings having a large proportion of high root volumes will outperform a population having a large proportion of low root volumes in the field. Fertilization at the time of planting had no effect on survival or growth because of shallow placement of the fertilizer pellet. The results suggest that targeting root volume, as well as height and diameter, is worthwhile where morphological quality must be maximized to improve field performance. Thus, root volume has potential for use as a criterion for grading seedlings.     

陇川柠檬优质高产栽培技术

介绍陇川县柠檬引种、推广种植现状,根据多年柠檬种植的生产经验,总结出柠檬优质高产栽培技术。     

安徽省松材线虫病防治的思考

本文在总结安徽省发生松材线虫病23年来治理经验的基础上,提出了下一步防治工作分三步走的总体思路,并从管理和技术方面探讨了一些应该注意的问题。     

创新是企业成长的核心要素

企业成长的关键是要有较强的赢利水平和能力,这决定于企业的生产能力、营销能力、科研能力和管理能力等因素。创新是基于需要的一种有目的的变化,又是诸因素变强的一个共同原因。创新的关键是要紧紧抓住稍纵即逝的需要信息,要有“为动而动”的精神。成长的企业必须要强迫自己不断地进行创新。     

Regional Architecture and Design Practice

Taking a project practice for example,this paper probed into the design methods of regional architecture in such aspects as geographic environment,traditional folk residence style,space environment and construction material etc.In this paper,one of the developing directions of modern architecture,i.e.the regional architecture design is pointed out first,then,the correlation between regional architecture and natural environment as well as historical culture tradition,space environment and material application of regional architecture,etc.were systematically discussed,it also indicated that the regional architecture should be an organic renewal of traditional folk residence style.It is concluded that the regional architecture should be in accordance with the nature.     

Selection of Polymeric Flocculant for Adjusting the Sludge Quality of Municipal Wastewater Treatment Plants

The thickened surplus sludge from municipal wastewater treatment plants is generally mechanically dewatered after regulated with flocculants and the type and dosage of flocculants will influence the dewatering effect directly.And the cost of flocculants is the main part of operating cost of sewage sludge treatment.With the processing practice on yields,thickening and dewatering pattern of Zhenjiang Wastewater Treatment Plant,the analysis and selection of flocculants are carried out with respect to the type and dosage of flocculants for sewage sludge regulation.the principles for flocculants selection and simple calculation method for chemicals cost for sludge treatment are proposed.It is suggested that the dosage of flocculants for sludge regulation should be adjusted in different seasons in real operation of the municipal wastewater treatment plants.     

应用型本科院校食品科学与工程专业实验教学体系改革与探索

发展应用型本科教育是我国高等教育大众化背景下的必然选择。依据地方经济建设需要,结合学校自身人才培养特色,建立食品科学与工程专业以应用能力培养为主的"基础性实验+综合性实验+创新性实验"三级实验教学平台,以培养学生实践操作能力、综合应用能力、创新能力等为主要人才培养目标的实验教学体系。     

Practical critique: Bridging the gap between critical and practice‐oriented REDD+ research communities

Reducing Emissions from Deforestation and Forest Degradation (REDD+) is an ambitious global programme oriented towards improving forest carbon management. It aims to attract new sources of ‘green’ capital to fund emissions reductions from avoided deforestation and sustainable forest management. REDD+ is transforming forest conservation, as a diverse array of new stakeholders become involved. Not surprisingly, REDD+ has proved divisive, as critics concern themselves with issues of power, justice, and commodification, while practice‐oriented researchers tackle similar issues from different perspectives, focusing on benefit sharing, safeguards, additionality, measuring and verification. In this paper we explore the different roles of critical and practical research, and argue that there is a need for greater sharing of knowledge across current divides. We draw on our own experiences of conducting a research project on REDD+ in Indonesia that involved critical and practice‐oriented researchers. We argue that critical research disconnected from practical matters can have perverse outcomes for practitioners who are ultimately working towards similar goals; while uncritical practice‐oriented research has the potential to lead to a dilution of core values of environmental justice and conservation. In contrast, forms of practical critique provide ways of researching REDD+ that have practical value while maintaining critical insights.     

The use of general and specific combining abilities in a context of gene expression relevant to plant breeding

Many common traits are believed to be a composite reflection of multiple genetic and environmental factors. Recent advances suggest that subtle variations in the regulation of gene expression may contribute to quantitative traits. The nature of sequence variation affecting the regulation of gene expression either in cis (that is, affecting the expression of only one of the two alleles in a heterozygous diploid) or in trans (that is, affecting the expression of both alleles in a heterozygous diploid) is a key and usually unknown feature for the breeders. If the change in expression acts entirely in cis, then the structural gene can be treated as a candidate gene and a potential target for marker-assisted selection. Therefore, gene surveys for cis-regulatory variation are a first step in identifying potential targets for marker-assisted breeding. Here, we discuss in detail the “genome-wide analysis of allele-specific expression differences” (GASED) approach. The GASED approach was developed to screen for cis-regulatory variation on a genome-wide scale. In GASED, mRNA abundance is treated as if it were a quantitative phenotypic response variable, whose genetic between-F₁ hybrid variance is partitioned into additive and non-additive components. In plant breeding, this partitioning of the genetic variance is well known in the context of estimation of general and specific combining abilities for diallel crossing schemes. We demonstrate the GASED method using Arabidopsis thaliana data. The method can be used to screen for cis-regulatory variation in any crop species for which diallel crossing schemes are appropriate and genomic tools are available.     

Responses to selection and changes in combining ability after three cycles of a modified reciprocal recurrent selection in maize

This research reports responses to selection and changes in general (GCA) and specific (SCA) combining abilities after three cycles of a modified reciprocal recurrent selection procedure (MRRS) in EPB-4 and EPB-5 maize populations. In the MRRS procedure a cycle can be completed in 1 or 2 years depending on the availability of winter breeding nurseries. The original and the three selection cycles of the two populations per se (eight entries) and the partial diallel developed from the crosses between them (16 entries) were evaluated in six environments. Realized response to selection on the population cross was 7.25% cycle⁻¹ for grain yield, −13.63% cycle⁻¹ for plant lodging, and 11.93% cyle⁻¹ for prolificacy, whereas plant and ear heights remained unchanged. GCA estimates increased with selection cycles for both populations for grain yield and prolificacy, and decreased for plant lodging, indicating that the frequency of favorable alleles with additive effects for these traits increased with the MRRS cycles in both populations. SCA estimates increased for grain yield and prolificacy indicating that the frequency of favorable complementary alleles at loci with non-additive effects in the reciprocal populations increased with the MRRS cycles. For grain yield, SCA effects increased more than GCA effects with selection cycles, indicating that MRRS exploited more the non-additive effects than the additive effects for the improvement of this trait. The overall results showed that the MRRS procedure was highly effective in improving the population cross, exploiting both GCA and SCA effects.