Rice variety improvement and the contribution of foreign germplasms in China

The introduction and use of foreign germplasms have played an important role in the improvement of crop varieties in China. Based on published materials and scientist interviews, we collected data on the sown area, morphological characteristics, and pedigree of the popular rice varieties grown in the 15 major rice production provinces and 1 autonomous region in China, from 1982 to 2011. Results showed that China＇s scientists developed the largest number of rice varieties worldwide, and that rice yield potential and grain quality have substantiality improved during the studied period. In contrast, resistance of newly-released varieties to diseases and insect pests has decreased since the 1990s. Germplasms from the Interna- tional Rice Research Institute （IRRI） and from Japan have contributed 16.4 and 11.2% of genetic materials to China＇s rice varieties developed between 1982 and 2011, respectively. While IRRI＇s materials contributed to the improvement of yield potential, growth duration, and blast and bacterial blight resistance, Japanese materials contributed to the improvement of grain quality. Materials from other countries contributed to the improvement of resistance to diseases and insect pests, particularly to rice blast disease, brown planthoppers, white-backed planthoppers, and striped stem borers.

Status of Agricultural Production and Crop Variety Improvement in Thailand

We introduced basic conditions of agricultural production in Thailand, and variety improvement of major crops, including rice, cassava, rubber, and vegetable, in the hope of providing reference for agricultural production and crop variety improvement in Hubei Province and even in the whole country.

Factors Affecting Adoption of Improved Rice Varieties among Rural Farm Households in Central Nepal

The use of improved high yielding crop varieties is an important avenue for reducing hunger and food insecurity in developing countries. Using cross-sectional data obtained from a survey conducted during 2013 crop season, we performed a probit model （plot-level analysis） to determine the probability of adopting new improved rice varieties （NIRVs） by smallholder farmers particularly from two main agro-ecological regions （hills and tropical plain terai regions） of Central Nepal. The results revealed that education, extension services and seed access play significant roles in adoption decisions. Additionally, farm and field characteristic variables such as farm size, endowment of favorable land type （e.g. lowlands）, and animal power （e.g. oxen） are the key factors influencing the probability of adopting NIRVs. The results showed that technology specific variables （e.g. yield potential and acceptability） are significant for explaining adoption behavior, implying that it is important to take farmers＇ preferences to varietal characteristics into consideration in the design of a research and development program. Given the significant role played by extension and access related variables, increased emphasis on information dissemination, field demonstration, and farmers＇ participatory research and training programs to popularize new rice varieties and enhance their adoption rate are required. This also suggests that policy intervention should be made on improving the educational status of farming households, and developing programs on varietal package of rice seed which offer farmers a variety of choices among the appropriate pools of germplasm. Such programs ultimately help farmers develop more profit-oriented behavior which are necessary to enhance adoption rate, production and food security in the long run.

Determinants of Adoption of Improved Rice Varieties in Northern Sindh, Pakistan

Adoption of certified and improved high-yielding crop varieties is important avenue for increasing agricultural productivity and improving the living standard of the farmers in developing countries. The main objective of the current study was to examine factors affecting adoption of improved rice varieties by smallholder farmers in Northern Sindh, Pakistan. The random sampling technique was used to collect data from 220 smallholder rice farmers through the face to face interview. Data were analyzed using descriptive statistics and probit regression model. The empirical results showed that year of education(P ≤ 0.093), farming experience(P ≤ 0.043), soil quality(P ≤ 0.077), farm machinery ownership(P ≤ 0.000), access to market information(P ≤ 0.055) and contact with extension agents(P ≤ 0.006) had significantly positive influence on adoption of improved rice variety, while age(P ≤ 0.053) had significantly negative effect.

Assessing Reactions of Genetically Improved and Local Cassava Varieties to Cassava Mosaic Disease (CMD) Infection in a Savannah Region of the DR-Congo

The responses of eight genetically improved and eight local cassava varieties to cassava mosaic disease (CMD) were evaluated under field conditions at two sites, in Eastern Kasa?, region of the DR-Congo). The varieties were planted using randomized complete block design with three replications. The rate of cuttings sprouted varied significantly from variety to variety and from location to location. Local varieties were severely infected than improved varieties throughout the trial period. In general, the level of CMD incidence for genetically improved varieties was below 15% while it reached 100% for the local cassava varieties six months after planting (MAP). This trend was also observed for the CMD severity and gravity. The mean scores for CMD severity were 2 and 3.6 for genetically improved and local varieties, respectively at 6 MAP. CMD gravity for improved varieties was below 21% for genetically improved varieties and exceeded 85% for local varieties at the end of trials. Area Under the Severity index Progress Curve (AUSiPC) and Area Under Disease Progress Curve (AUDPC) estimates confirmed that improved varieties were moderately infested comparatively to local varieties. Molecular analysis is being conducted to determine the genetic variability and complexity of the cassava mosaic virus strains involved.

Analysis of Genetic Similarity for Improved Japonica Rice Varieties from Different Provinces and Cities in China

To provide a genetic basis for japonica rice breeding, the genetic similarity and cluster of 139 accessions of improved japonica rice varieties from 12 provinces and cities of China were analyzed using 34 SSR markers. Totally 198 alleles were detected among these improved japonica rice varieties with the average number of alleles per pair of primers was 5.3235. RM320, RM531, RM1, RM286, and RM336 showed more alleles, which were 15, 12, 11, 9, and 9, respectively. RM320, RM336, RM286 and RM531 showed higher genetic diversity indexes; which were 2.3324, 2.0292, 1.8996, and 1.7820, respectively. The range of genetic similar index among improved japonica rice varieties from different provinces was from 0.321 to 0.914, with the average of 0.686. There was a high genetic similarity among improved japonica rice varieties from Heilongjiang, Jilin, Liaoning, Ningxia, and Yunnan, which were located in similar latitude or similar ecological environment, while there was a low genetic similarity between improved japonica rice varieties from Guizhou and Jiangsu, and other provinces which were located in more different latitudes and ecological environments. The markers of RM320, RM531, RM1, RM286, and RM336 fit to be used in analysis of genetic diversity for improved japonica rice variety. The genetic similarity among improved japonica rice varieties from different provinces was closely associated with genetic basis of parents, and was also correlated with latitude and ecological environment where the varieties were bred.

Genetic Improvement in Juglans mandshurica and Its Uses in China:Current Status and Future Prospects

Juglans mandshurica is an economically and ecologically valuable species that is used for various construction purposes,making luxurious furniture,as food and sources of medicinal substances and landscaping because of its excellent wood,edible fruits and rich in various types of chemical compounds.In the past few decades,several genetic improvements of J.mandshurica were made,with a focus on the selection of improved varieties and on breeding technology.Many elite provenances and families were selected based on growth traits or wood properties.In recent years,with the increasing demand for high-quality seedlings in Chinese forestry production,the breeding goals of genetic improvement for J.mandshurica were redefined to include other traits,such as fruit yield and contents of medicinal component.However,the improvement processes were still slow due to the long breeding cycle and the limited use of advanced breeding technologies,resulting in the selection of fewer improved varieties.In this review,we summarized the research progresses on genetic improvements of J.mandshurica and other related works,and discussed research gaps and suggested future directions for genetic improvement of the species.The review provides valuable insight for the selection of improved varieties and production of excellent germplasms.

Analysis of Adoption of Improved Groundnut Varieties in the Tropical Legume Project (TL III) States in Nigeria

Agricultural technologies and innovations play a great role in increasing productivity, alleviating and reducing poverty and contributing to economic development and this is made possible through adoption of improved technologies and innovations. This study centered on analysis of adoption of improved groundnut varieties in the Tropical Legume (TL III) States of Nigeria. Purposive and simple random sampling techniques were used to select 1476 groundnut farmers in the project States and from whom primary data were collected using electronic data capturing instrument containing the questionnaire. The data were analyzed using descriptive statistics and Average Treatment Effect (ATE) framework. The results showed that the breeding and promotion of improved groundnut varieties in Nigeria under the Tropical Legume Project and with the synergy of USAID groundnut up-scaling Project in Nigeria resulted in very high level of awareness of improved varieties, more than average level of access to the improved variety seeds, moderate level of utilization of the improved varieties among the groundnut farmers and the adoption rate of improved varieties increased from 8% at based line to 57% at the end of the project. The study recommends extension of the project to facilitate further access to these varieties and for state governments to take ownership of the projects in terms of financial commitments to promotional efforts for mass adoption by farmers.

Adoption of Improved Rice Varieties in the Global South:A Review

Improved rice varieties(IRVs)play a significant role in establishing food security and improving livelihood in the Global South since its introduction in the 1960s.However,the adoption of new IRVs has remained relatively low.This low adoption poses a challenge to rice-producing and consuming countries as they are increasingly threatened by production shortages,malnutrition,and poor rice quality.Many empirical studies have attempted to identify the determinants influencing the adoption of IRVs by distinguishing the characteristics between adopters and non-adopters.This review showed a consensus on the important determinants influencing the adoption of IRVs in the Global South.Findings synthesized from 99 studies suggested that variables(farm size,education,information access and farm location)examined extensively are not necessarily the most important determinants of adoption when undertaking a weighted analysis.Terrain,source of seed and technology-related attributes(perceived yield,maturity,ease of use,marketability and technical efficiency)are more important determinants of adoption,with determinants changing according to adoption type(probability or intensity of adoption),variety type and region.The recommendations for future adoption studies include:incorporating more technology-specific variables,increasing research for overlooked regions and variety types,shifting away from predominant static analysis by capturing the dynamics of the adoption process,and considering the potential biases in analyses.This review will facilitate the development of targeted interventions and policies that promote IRV adoption in the Global South.

Ex-ante Adoption Analysis for Improved Sorghum Varieties in the Lake Zone Tanzania

The objective of this study was to determine the influence of production and consumption characteristics of improved sorghum varieties on farmers＇ adoption decisions. Thirty-four farmers and 231 consumers evaluated five sorghum varieties to determine their preferences. The perceptions of the farmers and consumers were summarized and presented to 100 sorghum farmers to help them choose the best varieties, based on results obtained earlier. Ordered probit models were used to predict their adoption decisions. Results indicated that when adoption is predicted on production characteristics alone the adoption rate was lower than when prediction incorporated both production and consumption characteristics of the sorghum varieties. Therefore, when disseminating new technologies farmers need to be informed about the production as well as the consumption characteristics of the new technologies. The outcomes of this study imply that involving producers and consumers in the generation of new agricultural technologies would potentially increase their adoption rates when they are disseminated. Thus a subsector analytical approach is recommended.

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.

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.

Durum Wheat Bread： Old Sicilian Varieties and Improved Ones

In Mediterranean countries and particularly in Southern Italy, durum wheat （Triticum durum Desf.） is traditionally used for bread production. Market globalization has created, also in these regions, the spread of bread made with soft wheat flour （Triticum aestivum L.） standardizing this product flattening consumers＇ taste. With the aim of re-evaluating the old Sicilian local varieties, some landraces, chosen from the genebank of the institute, have been multiplied on farmers＇ fields to have enough material for making bread and for comparing this product with bread made by improved new varieties. Before milling in the pilot plant, the different wheats were characterized for their merceological indexes. The semolina obtained was analyzed for its chemical parameters. Rheological tests were conducted on dough and, finally, using standardized methods, one-variety breads were produced. On the bread slices, computerized image analysis was performed to measure colour and morphological parameters of crumb and crust. Sensory analysis, achieved through a descriptive profiling test, was conducted with trained judges using touch, fragrance and taste attributes for the different bread types. The different merceological, chemical and theological properties of raw material, grain and semolina were reflected in the breads prepared using old or improved varieties. Finally, the data obtained pointed out that the bread prepared with old and improved varieties can be clearly distinguished both by objective morphological parameters （image analysis） and by sensorial evaluations, for a potential traceability of typical product.

Changes in starch quality of mid-season indica rice varieties in the lower reaches of the Yangtze River in last 80 years

Rice (Oryza sativa L.) quality depends mainly on the characteristics of starch stored in kernels. Understanding the changes in starch characteristics in kernels during variety improvement would have great significance to improve rice quality. This study was designed to investigate the starch characteristics in the kernels and associated physiological traits of indica rice varieties in the lower reaches of the Yangtze River in China in last 80 years. Eight representative mid-season indica rice varieties were grown in the field. The results showed that the grain yield was significantly increased with the improvement of varieties and such an increase was mainly attributed to the increase in total number of spikelets. The tall varieties applied in the 1940s–1950s had higher protein content, relative crystallinity and infrared (IR) ratio of 1 045/1 022 cm^–1. The semi-dwarf varieties applied in the 1980s–1990s had higher gel consistency, amylopectin content, IR ratio of 1 022/995 cm^–1, and breakdown value. With the improvement of varieties, the amylose content, large-sized starch granule number and volume distribution, onset and peak of gelatinization temperature, gelatinization and retrogradation enthalpy, setback value, pasting temperature, viscosity of peak, hot and final, and 1-aminocycopropane-1-carboxylic acid (ACC) concentrations in panicles and root bleeding were gradually decreased, whereas the medium-sized starch granule number and volume distribution, activities of key enzymes in grains, and zeatin (Z)+zeatin riboside (ZR) contents in panicles and root bleeding at grain filling stage were gradually increased. Correlation analysis showed that starch thermodynamic characteristics were closely related to starch structure and components, key enzymes and hormones. The results suggest that starch quality was enhanced through the optimization of starch components, structure, thermodynamics, and the regulation of key enzymes in grains and hormones in panicles and root bleedings at grain filling stage during the improvement of mid-season indica rice.

Morphological and physiological traits of large-panicle rice varieties with high filled-grain percentage

financed by the Special Program of Super Rice of Ministry of Agriculture, China （02318802013231）;the National Public Services Sectors （Agricultural） Research Projects, Ministry of Agriculture, China （201303102）;the Great Technology Project of Ningbo, China （2013C11001）

A Gender Analysis on the Participation and Choice of Improved and Local Haricot Bean (<i>Phaseolus vulgaris L</i>.) by Farmers in Cameroon

Men and women farmer participation and choice of variety could guide breeding and drive the adoption of different haricot bean varieties. Thus, understanding how gender influences participation and choice of bean cultivation and marketing is fundamental. The study sought to analyse how socio-cultural norms determine women and men, participation and choice of variety for cultivation and sale in Cameroon’s West region. A mixed-method was used in collecting data from men and women farmers in six subdivisions in the West region of Cameroon in 2019. Result reveals that women provide most of the labour on haricot bean production than men, who are more involved in selling to national and regional markets. Participation and role were driven by socio-cultural norms of what is expected of men and women in a society where women provide food and men income for household upkeep. Women preferred varieties that were less labour intensive and food taste for household consumption while men went for labour intensive as long as they were market-oriented and high yielding. Thus, breeders should develop varieties that are mostly preferred by women, which meet the market and household demand.

Technological Properties of Improved Pigeon Pea Varieties in Machakos County, Kenya

Pigeon peas, a type of pulse, have immense nutritional potential to improve health in arid and semi-arid regions. However, unlocking this potential relies heavily on understanding their technological properties, such as hydration rate, volumetric expansion, and cooking time. These properties directly influence processing, accessibility, and acceptability as a food source. However, there is limited information on technological properties of improved varieties. The study aimed to determine technological properties of improved pigeon pea varieties grown in Machakos County. Seven improved pigeon peas varieties namely: KARI Mbaazi 1, KARI Mbaazi 2, ICEAP 00850, KAT 60/8, Mituki, Egerton Mbaazi 1, Egerton Mbaazi 2 and ICEAP 00554 (control variety) were used in this study. These varieties were tested for water absorption capacity (WAC), volumetric expansion, density, cooking time (CT) and total soluble solids (TSS) in the broth. The experiment was arranged in a Completely Randomized Design (CRD) replicated three times. Data analysis was conducted using SAS software version 9.1.3 (SAS, 2006). Means separation was done using Tukey’s honestly significant difference (HSD) at 95% Confidence Level. There were significant differences in water absorption capacity (WAC), volumetric expansion, density, TSS, and CT among the improved varieties (p p < 0.05). KARI Mbaazi 2 exhibited the greatest volumetric expansion after cooking (VEAC) at 11%. Additionally, control variety recorded the highest water absorption capacity (125.48%), which was significantly greater compared to the improved pigeon pea varieties. Cooking time in minutes was shortest for Mituki (46.0) and KAT 60/8 (55.7) and longest for both KARI Mbaazi 1 and ICEAP00850 at 160 minutes. All the varieties showed high TSS ranging from 10.5 to 26.7% indicating the potential to select varieties with desired flavour profiles. Improved pigeon pea varieties (Mituki and KAT60/8) displayed desired technological properties alongside the control variety. These findings inform the specific culinary applications and nutritional needs which enhance utilisation of pigeon peas as food. Further research is needed to determine the impact of the technological properties on the digestibility and glycaemic index of pigeon peas.

Production of Wood Fibers from Thermally Treated Wood

The reduction of the hygroscopicity of wood fibers was investigated through a Thermal Treatment(TT)on wood chips performed before the defibering process.The TT and defibering tests were both carried out on a continuous pilot at semi-industrial scale.The thermal treatment study of wood chips,equivalent to a low temperature pyrolysis,was achieved for four conditions(280°C–320°C)for a duration of 10 min.Mass quantification of solids,condensables and gases(FTIR)at the outcome of the thermal treatment allowed to achieve the mass balances for each condition.The increase of the reactor temperature from 280°C to 320°C leads to a lower solid yield(94%–82%)while gaseous(1%–3.8%)and condensable(3%–11%)products increase significantly.Thermally treated wood samples were afterwards successfully defibered in different conditions to produce suitable fibers for insulation panel production.The aim of the study is also to evaluate the effects of the TT on the lowering of energy consumption necessary for the defibering process while producing good quality fibers.Energy consumption during defibering process shows a significant decrease with the increase the TT severity.Fiber morphology is affected by TT and the morphological quality of the fibers decreases as TT severity increases.The mass percentage of dust was also quantified as a quality marker of produced fibers.Measurements of equilibrium moisture(at 20°C and 65%RH)of the different materials(wood chips before and after TT,produced fibers)show a significant effect of the TT on wood chips hygroscopicity(8.2%for untreated wood to 4.1%for TT at 320°C).However,the effect of the TT on the hygroscopicity reduction of thermally treated wood fibers is drastically less significant due to breaking of the wood structure during defibering process.

基于国内外大豆品种比较的中国大豆品种改良路径探索

我国的大豆生产落后于世界大豆主产国,从品种角度看,存在着单产水平低、油分含量低等问题。本文对主产国大豆品种研发应用情况以及美国大豆品种发展趋势进行分析,明确了美国在大豆种质的资源研究、育种技术研发、品种特性鉴定以及环境因素研究等方面对于大豆品种研发的促进作用。通过对中美大豆品种特性的全面比较分析,明确我国大豆品种在单产、含油量、种植密度等方面的差距,提出了快速提升我国大豆品种产量和品质的路径,即通过对高油大豆资源进行表型精准鉴定,研发全基因组选择、转基因等高效育种技术,聚合产量和其他优异性状,创制优异大豆种质,设计培育高油高产突破性品种,以期为中国大豆品种改良研究提供参考。

广西笋用竹种质资源及其利用调查

调查了广西的笋用竹种质资源及其利用现状,结果显示,广西适宜笋用的竹种有6属41种(包括变种或品种)。其中,夏季出笋的竹种有3属24种,以大型丛生竹——麻竹种植面积较大,甜龙竹发展潜力大;冬、春季出笋的竹种有2属14种,以大型散生竹——毛竹种植面积最大,但以材用林为主,笋产量较低,刚竹属、大节竹属的其它笋用竹种有零星种植;秋季出笋的竹种有寒竹属1属3种,其笋亦称为“重阳笋”,利用较少。在笋用竹种中人工种植面积在6.67 hm^(2)以上的有麻竹、勃氏甜龙竹、绿竹、毛竹和雷竹5种。调查中还发现了一些新的笋用竹种,竹笋品质佳,但种群量少,处于濒危状态。广西发展笋用竹应重视多种竹种的利用,既要发展麻竹笋用林,也要发展甜龙竹、毛竹及寒竹属竹种等的笋用林,构建全年供笋格局;加大广西本土优良笋用竹种及濒危笋用竹种的培育与利用,选育笋用竹良种,并加快推广种植。