水稻产量库相关穗部性状的遗传分析(英文)

收集了源于珍汕 97 明恢 6 3的重组自交系群体中与产量库容有关的 10个穗部性状的表现型数据。总体上 ,每穗颖花数与每穗二次枝梗数、每个二次枝梗上的颖花数、颖花密度有更大的相关性。对所研究的 10个性状 ,两年间共检测到 5 3个QTLs。约 4 3.4 %的QTLs能在两年同时检测到。 5个染色体区域 (第 1染色体上G35 9 RG5 32和C5 6 7 C86 RG2 36 ,第 2染色体上R712 RM2 9,第 6染色体上P RG4 2 4 ,第 10染色体上C14 8 RM2 5 8)分别对多个穗部性状表现出效应。结果显示相关性状的QTLs大致定位在相似的染色体区域 ,这表明基因的多效性或紧密连锁是穗部性状间相关的遗传基础。在检测到的大量 2位点互作对中 ,约 18.2 %在两年都能被检测到。不同性状的共同互作对的比例为 8.7%～ 32 .6 %。在两年都能检测到的 2位点组合中 ,约 2 6 .7%的组合同时影响着多个性状 ,表现出多效效应。结果表明每个性状都由数个QTL、基因型与环境互作。

Effects of Planting Density on Yield and Sourcesink Characteristics of Sweet Potato[Ipomoea batatas(L.) Lam]

[Objective] The aim was to resolve the issue of sparsely planting （37 500-40 500 plants/hm2） of sweet potato in hilly areas. [Method] The starch-oriented Jishu No.21 and raw-eating oriented Jishu No.22 were studied to explore effects of planting density on yield and sink and source characteristics of sweet potato. [IRe- suit] Leaf area index of Jishu No.21 and Jishu No.22 were increasing upon planting density. Leaf area index of the same planting density showed a single-peak curve. Specifically, leaf area index grew fast during the 40th-80th d after planting, and reached the peak on the 80th d after planting, followed by decreasing. What＇s more, ventilation and sunshine transmission both declined upon planting density, as well as the number of leaf, the number of branch, the length of vine, dry and fresh weights of stem and leaf. When planting density exceeded 75 000 plants/hm2, the yield of sweet potato dropped dramatically. Besides, the optimal planting density tended to be volatile upon cultivars. For example, the range of 45 000-60 000 plants/hm2 is the optimal planting density of Jishu No.21 and the range of 60 000-75 000 plants/hm2 is the optimal planting density of Jishu No.22. [Conclusion] It can be concluded that rational planting densities would well coordinate sweet potato growth of ground parts and underground parts to get a high yield by providing a rational group structure. Considering the optimal planting density differs upon cultivars, it is necessary to take genotype, environment, soil fertility and planting density into consideration in determining planting density.

Relationship between Grain Yield and Yield Components of Various Rice Cultivars

[Objective] The relationship between grain yield and yield components was investigated in .different rice cultivars at the target yield of 10.5-11.25 t/hm2, to provide theoretical basis for cultivation of high-yield rice. [Method] The yield performance of various super rice and non-super rice cultivars that were cultivated in large area in Sichuan Chengdu was studied under high-yielding cultivation conditions from 2006 to 2008. [Result] The rice yield was closely correlated with the productive panicle number, grain number per panicle, seed setting rate and 1 000-grain weight. The four yield components showed different influences on the yield of different rice culti- vars. By adopting the high yielding cultivation technology （that the seedlings were planted in a triangle shape） at the target yield of 10.5-11.25 t/hm~, we found that the rice yield of super rice cultivars was closely correlated with productive panicle number and 1 000-grain weight, negatively correlated with grain number per panicle, and significantly negatively correlated with seed setting rate; the grain yield of non- super rice cultivars was negatively correlated with grain number per panicle and seed setting rate, and significantly negatively correlated with the productive panicle number and 1 000-grain weight. [Conclusion] The results revealed the relationship between grain yield and yield components in different rice cultivars, which provided references for developing reasonable cultivation measures and thus to improve the yield of super rice in large acreage.

Effect of Source-sink Change on Photosynthesis and Yield of Wheat

[Objective] The paper aims to explore the influences of source sink change of wheat at different densities on wheat yield.[Method] 225 （D1） and 320 plant/m2（D2） were adopted,then cutting flag leaf （L1）,the second last leaf （L2）,removing upper part of spike （L3） and controlling （CK） were used to conduct field experiment.[Result] The results showed that both of the two densities of wheat＇s 1 000-grain weight and grain filling rate after anthesis in a decreasing order of L3〉CK〉L2〉L1,and the grain weight per spike and dry matter amount translated after anthesis turned to be CK〉L2〉L1 〉L3.[Conclusion].Both of leaf-cutting and spikelet removing decreased the grain weight per spike and dry matter amount translated after anthesis.Removing upper part of spike increased wheat＇s 1 000-grain weight.But the decreasing of the sink and dry matter amount translated contributed to the decreasing of the yield of wheat.

Methods Comparison for Microsatellite Marker Development:Different Isolation Methods,Different Yield Efficiency

Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology,quantitative genetics and genomics. Therefore,it is extremely necessary to select several versatile,low-cost,efficient and time-and labor-saving methods to develop a large panel of microsatellite markers. In this study,we used Zhikong scallop(Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency,while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time-and cost-saving,it is difficult to obtain a large number of microsatellite markers,mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study,we recommend two methods,microsatellite-enriched library construction method and FIASCO-colony hybridization method,for large-scale microsatellite marker development. Both methods were derived from the microsatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes.

Applied research of mathematical models in enterprise product sale

Some products are only sold in some regions while some are sold in certain months, so there are a lot of data gaps. If we choose too much of this vacancy data, it may have impact on knowledge extraction. So to aim at specific sale database, we chose to study six kinds of representative products among them and these products are relatively comprehensive in all regions and month sales including two conventional products, two special products and two accessories; we also chose seven sale regions to make detailed analysis. We selected nine characteristics of sales in database which respectively are monthly sales volume, monthly revenue, monthly average selling price, profit, program sales volume, completed percentage of a program, sales month, sales territory and product type.

Supply chain coordination with inventory risk allocation

Unlike the traditional decentralized channel,the drop-shipping channel entails a retailer relaying consumers’orders to the manufacturer,which proceeds to stock the orders and directly ship them to the consumers.This study explores supply chain coordination and product quality in drop-shipping and traditional channels.Specifically,we analyze the performance of both channels under wholesale price and revenue-sharing contracts.Our study yields several key findings.First,the revenue-sharing contract can coordinate both traditional and drop-shipping channels,effectively increasing supply chain performance.Second,given the channel structure,the retailer prefers the wholesale price contract,whereas the manufacturer prefers the revenue-sharing contract.Third,product quality is higher in the drop-shipping channel when demand uncertainty is high.Finally,the implementation of the revenue-sharing contract increases product quality in the traditional channel,whereas it keeps product quality unchanged in the drop-shipping channel.

ANALYSIS OF A PRODUCTION-INVENTORY MODEL WITH ERLANGIAN DEMAND ARRIVAL PROCESS

We study a production-inventory system having a machine, a storage facility. The demand for the product is governed by an Erlangian demand arrival process, where demand sizes are independent and identically distributed random variables. A two-criticalnumber policy (m, M) is used to control a machine's setups and shutdowns, namely, a machine is shut down whenever the inventory level reaches M, and resumes operating only when the inventory level falls below the critical number m(m ≤ M). We obtain the steady state distribution of the inventory process and some performance measures of the process.

A MULTI-PERIOD PRICING AND INVENTORY CONTROL MODEL

The authors analyze a finite horizon,single product,period review model in which pricingand inventory decisions are made simultaneously.Demands in different periods are random variablesthat are independent of each other and their distributions depend on the product price.Pricing andordering decisions are made at the beginning of each period and all shortage are backlogged.Orderingcost is a convex function of the amount ordered.The objective is to find an inventory and pricing policymaximizing expected discounted profit over the finite horizon.The authors characterize the structure ofthe optimal combined pricing and inventory strategy for this model.Moreover,the authors demonstratehow the profit-to-go function,order up to level,reorder point and optimal price change with respectto state and time.