论近代山东蚕丝业改良

论近代山东蚕丝业改良李平生山东蚕丝业有悠久的历史，早在商周时代已达到了相当的水平。春秋战国以降，有关“齐鲁千亩桑”的记载不绝如缕，齐纨鲁缟成为中国丝绸精品的象征，“齐鲁衣履冠带天下”的兴旺景象一直持续到盛唐时期。宋朝以后，随着全国经济中心的南移。山东...

我国畜禽品种改良成效显著

我国畜禽品种资源丰富,达260多个,但多数属较为原始的地方品种,生产性能低,产品率不高,有一些产品还不优质。为此,建国以来就着手畜禽品种改良,特别八九十年代畜禽品种改良事业发展速度又更快一些,取得了举世瞩目的成绩。

散花白千层挥发油成分的研究

通过测定散花白千层油的成分和得油率,并与改良种作对比,选择具有应用价值的白千层优良品种。

Genetic Improvement Progress and Productive Effect of Rapeseed in Henan Province

The research progress and major achievements on genetic breeding, het- erosis utilization of rapeseed in Henan Province were summarized, with the aim to provide technical guidance for rapeseed genetic breeding in the future work. Faced with the problems of lack of special varieties, highly demand for healthy oil and high production cost in rapeseed production in recent years, the breeding goals of rapeseed have been adjusted from high yield, high quality and disease resistance to high oil, high oleic acid, adaptative to mechanization, late planting resistance. The breeding technologies mainly focused on the isolated microspore culture, molecular marker assisted selection, and the corresponding high efficiency technical systems were constructed. The innovative research on excellent germplasm resources were carried on, which created and established breeding populations and distinctive new germplasm resources with diverse variations such as high oil content, high oleic acid content and low linolenic acid, cold resistance, drought resistance, pod shatter resistance and different flower color variations. A series of rapeseed hybrids of dou- ble low varieties with strong heterosis and high oil contents were released and these hybrids significantly improved seed yield, quality and resistance. The average yield of rapeseed in Henan Province was 22.49% higher than the national average yield in 2003-2015. All of the achievements provided strong technical support for the upgrading of rapeseed varieties and increasing both production and income.

绵羊产业成本收益区域比较研究

本文基于2004—2016年绵羊产业成本收益数据分析影响内蒙古、新疆、青海和宁夏等地区绵羊产业成本收益的因素,比较各地区的净利润、成本、成本利润率和成本结构。结果显示:各地区改良种绵羊的收益和成本均略高于本种绵羊。饲草费、饲料饲盐费、家庭用工折价、雇工费用、医疗防疫费和死亡损失费是影响各地区绵羊产业成本收益的重要因素,但成本构成有差异。此外,各地区在养殖过程中技术服务投入匮乏。对此,建议在注重改良的同时要加强对于本土品种资源的保护,降低养殖成本,加大基础设施投入并倡导科学养殖。

Changes in Agronomic Traits of Indica Hybrid Rice during Genetic Improvement

[Objective]The aim was to elucidate the changes of agronomical traits of indica hybrid rice during its genetic improvement.[Method]23 typical indica hybrid combinations cultivated in the middle and lower reaches of Yangtze River during the last 30 years were selected as experimental materials.All the hybrid rice combinations were grown in the same field;and then yield and morphological characters of single plant were compared;correlation and path analyses among agronomic characteristics were also conducted.[Result]During the 30 years of genetic improvement,the effective panicle number per plant was progressively decreased,which caused the decrease of grain yield and biomass per plant of hybrid rice combinations in spite of the slightly increased plant height,1 000-grain weight and number of grains per panicle.Although the transformation percentage of the matter in stem and sheath decreased after flowering,leave photosynthetic capacity after flowering was increased as panicle weight.Correlation and path analysis showed that although both biomass per plant and number of grains per panicle were significantly correlated with grain yield per plant,biomass per plant acted as the key factor affecting yield per plant.[Conclusion]It was suggested that in rice high yield cultivation,panicle number was as important as large panicle,and tillering ability should not be neglected in breeding.

上半年农垦畜牧生产仍保持稳中发展的势头

据农垦系统34个垦区(青海、新疆农业缺报)六月末统计,上半年猪的存栏头数、良种及改良种奶牛比去年同期分别增加了10.71万头和2.24万头,增长幅度分别为3.03％

Mechanism of Salt Tolerance in Rice

Shaheen Basma ti was evolved as a salt tolerant fine rice va riety by the Soil Salinity Research Institute,Pindi Bhattian, Pakistan. Water culture studies were conducted to investigate the physiological mechanismexercised by this variety in particular and rice plant in general to face the saline environment. Performanceof this rice variety and the concentration and uptake of ions were studied under stress of three salinity levels(30, 60 and 90 mmol L-1) created with NaCl. Recorded data indicated that shoot dry matter was notsignificantly affected by all the three levels of salinity. However, NaCl levels of 60 and 90 mmol L-1 affectedthe root dry matter significantly. Sodium concentration and uptake was enhanced significantly in root andshoot at the first level of salinity (30 mmol L-1) but thereafter the differences were non-significant, indicatingthe preferential absorption of this cation. The K concentration decreased significantly in shoots at all thelevels. The impact was less pronounced in roots as far as K absorption was concerned. The effect on Ca andMg concentrations was not significant. The values of K:Na, Ca:Na and (Ca+Mg):Na ratios in shoot and rootwere comparatively low under stress conditions, indicating that selective ion absorption may be the principalsalt tolerance mechanism of variety Shaheen Basmati when grown in a saline medium.

Microsatellite analysis of variation among wild, domesticated, and genetically improved populations of blunt snout bream （Megalobrama amblycephala）

In the present study, the genetic diversity of one selected strain （Pujiang No. 1）, two domesticated populations （GA and HX） and four wild populations （LZ, YN, SS and JL） of blunt snout bream （Megalobrama amblycephala） was analyzed using 17 microsatellite markers. The results showed that an average of 4.88-7.65 number of alleles （A）; an average of 3.20-5.33 effective alleles （Ne）; average observed beterozygosity （Ho） of 0.6985-0.9044; average expected beterozygosity （He） of 0.6501--0.7805; and the average polymorphism information content （PIC） at 0.5706-0.7226. Pairwise FST value between populations ranged from 0.0307-0.1451, and Nei＇s standard genetic distance between populations was 0.0938-0.4524. The expected heterozygosities in the domesticated populations （GA and HX） were significantly lower than those found in three wild populations （LZ, SS and JL）, but no difference was detected when compared with the wild YN population. Likewise, no difference was found between the four wild populations or two domesticated populations. The expected heterozygosity in Pujiang No. 1 was higher than the two domesticated populations and lower than the four wild populations. Regarding pairwise Fsr value between populations, permutation test P-values were significant between the GA, HX and PJ populations, but not between the four wild populations. These results showed that the expected beterozygosity in the selected strain of blunt snout bream, after seven generations of selective breeding, was lower than that of wild populations, but this strain retains higher levels of genetic diversity than domesticated populations. The genetic differences and differentiation amongst wild populations, domesticated populations and the genetically improved strain of blunt snout bream will provide important conservation criteria and guide the utilization of germplasm resources.

Behavioral Differentiation between Anas poecilorhyncha and Domestic Duck

Anas poecilorhyncha is one of improved variety of mallards, which was the protected bird species listed by International Union for Conservation of Nature （1UCN）. Little is known until now about behavioral characteristics of the mallard. The objective of this study was to compare the behavioral differentials between A. poecilorhyncha and domestic duck in order to make a strategy to manage A. poecilorhyncha under the condition of animal welfare. A total of 180 birds were distributed into six groups with 30 birds for each group. They were placed in a room of 3 m ~ 4 m and fed for one year old. Sansui ducks, a kind of native domestic duck （Sansui laying duck） were used for behavioral comparison. Two different rooms in the same building were applied, one room for A. poecilorhyncha and another one for Sansui ducks. All behaviors for A. poecilorhyncha and Sansui ducks were coded using the program The Observer XT 11.5 （Noldus Information Technology, Beijing）. The duration of observation was from 8：00 am to 18：00 pm daily and lasted 5 d. The results showed that there were similar behavioral percentages between A. poecilorhyncha and domestic duck. Percentages of standing activity spent for A. poecilorhyncha and Sansui duck were 34.59% and 30.25%, respectively. Accordingly, the activities, such as wing plugging, preening and head stretching, were more than 5.51%. The other activities, including walking, drinking and tail wagging, occupied less proportions （〈 3%）. While the specific behaviors, like aggression, alerting, wing dithering, clawing, nodding, pendulum clawing and crawling, took less than 1% of percentage. There were large differences between A. poecilorhyncha and domestic duck when comparing eight behavioral peaks. Lag sequential analysis was used to calculate frequency of transition between a pair of activities. Some parameters were very significant, like the frequency value from foraging converted to drinking in Sansui duck was 369-515, but 37-65 in A. poecilorhyncha. The best explaining could be given that Sansui duck was better domesticated than spot-billed duck. This study provides the basic data to study and develop spot-billed duck.

Impediments to New Improved Maize Variety Testing and Release in Selected Countries in Sub-Saharan Africa

Before farmers can benefit from new improved maize varieties with novel genetic information, new maize varieties have to undergo performance testing, registration and approval. The registration procedures require that new maize varieties must pass the tests for value for cultivation and use （VCU） and standardized tests for distinctness, uniformity and stability （DUS）. To meet the minimum requirements for variety release, public and private sector maize breeding programs routinely assemble breeding nurseries and evaluate variety performance in National and Regional Performance Trials （NRPT） with the objective of generating important agronomic data to identify the best maize varieties for release. In spite of intensive variety evaluation in regional and national trials, only few maize varieties have been registered and released annually in sub-Saharan Africa （SSA） denying farmers access to new improved varieties. The purpose of this study was to identify constraints hampering the registration and release of elite maize gennplasm and make recommends on how to quicken the deployment of elite germplasm to smallholders＇ farmers. A survey was conducted on the varietal testing and release systems in 14 selected countries （Angola, Benin, Ethiopia, Malawi, Ghana, Mali, Mozambique, Nigeria, Tanzania, Kenya, South Africa, Uganda, Zambia, and Zimbabwe） in SSA. The results from the study show that regulations on variety testing and release procedures in the various countries are overlapping and rigid hindering the deployment and commercialization of new improved maize germplasm. The study also showed that varietal release rates fluctuated between countries with South Africa having the highest number of varietal release rates per year and some countries failing to release a single variety per year.

Effective Approaches to Wheat Improvement in Kazakhstan： Breeding and Conservation Agriculture

International Maize and Wheat Improvement Center （CIMMYT） and Kazakhstan collaborative activities on wheat improvement are focused in the following main areas： （1） wheat germplasm enhancement： Kazakhstan-Siberian Network on Wheat Improvement （KASIB） and Shuttle Breeding ＂Mexico-KASIB＂ Programs; （2） Conservation agriculture （CA） for wheat production and crop diversification. Nineteen breeding programs of Kazakhstan and Russia are united by KASIB Network and Shuttle Breeding. By 2014, more than 15,000 wheat lines and varieties were involved in breeding programs of Kazakhstan and Russia; 10 varieties were developed and released. The KASIB Network and Shuttle Breeding Program were recognized as one of the best example of the effective regional and international cooperation in Kazakhstan and Russia. In the beginning of 2000 CIMMYT, National Agricultural Research System, the Ministry of Agriculture, FAO, World Bank in cooperation with farmers initiated large-scale activities based on CA in Kazakhstan. Due the joint efforts, area under CA-based practices has been increasing from virtually none to an estimated area of 500,000 ha in 2007, 1,200,000 ha in 2008, 2,000,000 ha in 2014 with continued rapid increases in area. Kazakhstan is now included among the top ten countries with the largest areas under no-tillage in the world.

Yield trait improvement of bay scallops following complete diallel crosses between different scallop stocks

This study describes the complete diaUel hybridization between newly introduced bay scallop stock （W） from Canada and local commercial stock （D） grown under laboratory conditions, in China. Larval survival and growth during all life stages （larvae, spat, and adult） were compared among hybrid （DW, WD） and purebred （DD, WW） populations. Significant heterosis was detected for survival during the larval stage （〉 1% of the mid-parent values）. The mean heterosis （Hm） varied in growth throughout the life span. More than 50% of the Hm values were positive and negative in the DW and WD groups, respectively. The influence of maternal effects and mating types （intrapopulation vs. interpopulation crosses） on growth for all life stages was not consistent. Larval survival did not differ significantly （P〉0.05） with maternal effect or mating type. In the harvest stage, shell length （SL）, shell height （SH）, shell width （SW）, and total weight （TW） were larger in the hybrid compared with the inbred groups. Positive Hm values were observed in SL （1.5%）, SW （5.8%）, and TW （12.3%）, and were more significant in the DW groups （6.1%, 4.5%, 6.8%, and 27.2%）. These results suggest that hybridization between two geographic populations is a good tool for improving bay scallop growth. However, unstable heterosis between the two populations requires further study.

Evaluating the Impact of Adoption of Improved Maize Varieties on Yield in Uganda： A Propensity Score Matching Approach

The main objective of this study was to evaluate the impact of adopting improved maize varieties on crop yield in Uganda using propensity score matching （PSM） algorithms to control for hidden selection bias. The study employed cross-sectional household data collected in 2005/2006 by the Uganda Bureau of Statistics （UBOS） across the country. Data were divided into two parts; the full sample and smallholder farmer sub-sample （those that cultivated less than 5 acres or 2 Hectares of maize in 2004 and 2005）. Then estimation was made of the difference in yields between the adopters and non adopters, the average treatment effect on the treated （ATT） for the full sample and smallholder farmer sub-sample. Matching methods were used to control for hidden selection bias and the standardized bias measure was used to check for the quality of matching. The results indicate that adoption of improved maize seed had a robust positive and significant effect on yields obtained by farmers. The results were consistent for both the full and smallholder farmer sub-samples. Sensitivity analysis using Rosenbaum bounds indicated that the ATT results were fairly robust to hidden selection bias. That is, the results were not sensitive to unobserved selection bias. Therefore it is confidently asserted that the estimated average difference in maize yields between the adopters and non-adopters was due to the effect of planting improved maize seed.

云南改良稻及元阳地方稻磷高效研究

在土壤有效磷质量比分别为0.26 mg.kg-1和80.0 mg.kg-1条件下对云南111份改良稻和77份元阳地方稻进行形态性状与程氏指数间的磷高效研究,以明确籼粳分化和米色与磷高效间相互关系,对比改良稻和地方稻间磷高效差异.结果表明:①相对地上干物质量、相对地下干物质量、相对总干物质量和相对分蘖力4个耐低磷指标性状可作为水稻耐低磷能力强弱评价的理想指标,能明确反映出磷高效能力强弱;②元阳地方稻各亚种间平均耐低磷能力均明显高于云南改良稻,且差异明显,4个耐低磷指标性状平均值为籼>偏籼>偏粳>粳,无色米>有色米,耐低磷能力随程氏指数的增大呈递减趋势;③总体而言,程氏指数和耐低磷指标性状间多数呈显著负相关,磷高效特性和籼粳分化密切相关.

Economic Impact of Mutant Cassava （Manihot Species） for Agricultural Improvement in Ghana

The importance of agricultural innovations for raising the living standards of farmers has received substantial attention from the economic and political communities. In Ghana, cassava serves as an important source of calorie and cash crop. Production constraints such as the cassava mosaic disease caused by virus have limit farmers access to productivity potentials and marketing. Breeding efforts attempting to address this constraints have had some success such as the mutant Tech Bankye virus resistant variety. This research, therefore, analysed the impact of some production input on mutant cassava productivity growth in Ghana with the use of Cobb-Douglas production function. Results show that farmers cultivate the mutant variety in addition to other traditional varieties to averse risking in marketing and income. The average cost of production of the mutant variety is higher compared to that of the traditional variety. Eighty percent of the farmers complained difficulty in accessing market for the mutant variety because it could not replace the traditional variety in terms of its texture for the local native ＂fufu＂ production and ＂ampesi＂ and also deteriorate quickly in storage. However, for industrial production of ＂gari＂ and starch, the mutant is the best. Both the mutant cassava and the traditional varieties showed increasing returns to scale, however, the returns to scale of the mutant variety were lower compared to that of the traditional variety. Also, the opportunity cost of forgoing the traditional varieties to cultivating the mutant variety was very high making adopted farmers hesitant to continue it cultivation.

Participatory Plant Breeding and Selection Impact on Adoption of Improved Sweetpotato Varieties in Uganda

This study analyzed the impact of participatory plant breeding （PPB） and participatory variety selection （PVS） on the adoption of improved sweetpotato varieties （ISPV） in central Uganda. The study quantitatively assessed how the two approaches influence farmers＇ uptake of the improved sweetpotato varieties and also determined other factors influencing this adoption. This was done by estimating a robust standard errors logit model. Both PPB and PVS positively and significantly influenced the likelihood of adoption of improved sweetpotato varieties at 5% and 10% levels, respectively. Other variables that positively influenced the adoption are extension services, training in sweetpotato production, farming experience, and off-farm income of the household. Farmers who participated in the plant breeding and variety selection processes were 37 and 6.7 times more likely to adopt the improved sweetpotato varieties than those who had not, respectively. Farmers who were trained specifically in sweetpotato production were 8.8 times more likely to adopt the improved varieties than those who had not received this type of training.

夏日的深渊

我凝望着写有“城户”的门牌,停下脚步。这座古色古香的宅邸,在燃烧着刺眼的白色烈焰的太阳下,分外沉寂,邻家也都鸦雀无声,仿佛沉浸在夏日午时的睡意中,笼罩着倦倦的氛围。

回家《末路小狂花》

这是一部有关回家的影片。 很久以来,在澳大利亚的吉格龙地区,一直居住着土著澳大利亚居民。自1905年起,澳大利亚政府颁布法令,命令将这些地区的土著后代,即所谓的“混血儿”集中至摩尔河营地,进行强迫改造,以达到改良种族的目的。于是,这项在1905年以后六十多年中实行的政府“绑架”行动,导致无数澳大利亚土著的后裔,被迫关进集中营地,他们从此失去了亲人,失去了家。 莫莉、戴西和格雷西就是三个被“绑架”的女孩子。与其他“混血儿”不同的是。

Principles and Practice of Forestation in Saline Soil in China

With world population growth arable land area is decreasing. Saline soil is an important naturalresource. However it has not been well reclaimed owing to adverse conditions. Forestation is one way of saltysoil utilization; on the other hand, it can improve soil quality as well. The mechanism of salinity tolerance isthe basis for tree species selection when planting in salt affected soil. Different plants have various way ofsalinity tolerance, some are salt-exclusion, e.g. Elaeagnus angustifolia; some are salt-secretion, e.g. Tamarixspp.; some are salt-dilution, e.g. Hordeum vulgare; some are salt-avoidance, e.g. Rhizophora apiculata. Treesare favorable, which are salt tolerant and drought or waterlogging tolerant, as well as grow fast. After treespecies have been decided, site preparation including change or exchange of soil is necessary. Meanwhilesuitable density of trees and planting time must be carefully considered in terms of soil conditions andclimatic characteristics. Now a large scale of forests has been established in salt-affected soil in China by themeans discussed in the paper, and protect forest system along coast plays important roles in socio-economicsustainable development and improvement of eco-environment.