Seed Storability in Rice: Physiological Foundations, Molecular Mechanisms, and Applications in Breeding

Long-term storage of crop seeds is critical for the conservation of germplasm resources, ensuring food supply, and supporting sustainable production. Rice, as a major food staple, has a substantial stock for consumption and production worldwide. However, its food value and seed viability tend to decline during storage. Understanding the physiological responses and molecular mechanisms of aging tolerance forms the basis for enhancing seed storability in rice. This review outlines the latest progress in influential factors, evaluation methods, and identification indices of seed storability. It also discusses the physiological consequences, molecular mechanisms, and strategies for breeding aging-tolerant rice in detail. Finally, it highlights challenges in seed storability research that require future attention. This review offers a theoretical foundation and research direction for uncovering the mechanisms behind seed storability and breeding aging-tolerant rice.

Breeding and Seed Production Techniques of New Aromatic Danxiangyouzhenliang Rice Variety with Good Quality and High Yield

Danxiangyouzhenliang rice is a high-quality rice variety derived from the hybrid breeding of Danxiang 12A and Xianghuixiangmiao R133.Its unique temperature-sensitive three-line characteristics endow it with significant advantages of high and stable yield,and its rice fragrance is exquisite and its taste is delicate.Danxiangyouzhenliang rice showed good resistance to rice blast and bacterial blight.On June 10,2021,Danxiangyouzhenliang rice passed the Guangxi Crop Variety Approval(Guishendao 2021074).Danxiangyouzhenliang rice is suitable to be planted as early and late rice in southern,central and northern Guangxi.This study summarized the breeding process and high-yielding seed production techniques of Danxiangyouzhenliang rice,in order to provide useful reference for rice breeders and growers.

Breeding of High-Quality Late Rice Combination Taoxiuyouhuazhan

Taoxiuyouhuazhan is a high-quality fragrant late rice combination which was bred by the cooperation between Hu Nan Tao Hua Yuan Agricultural Technologies Co.,LTD.and Changde Institute of Agriculture and Forestry Science.With good yield,wide adaptability,resistance to rice blast,and the quality reaching third level of the national agricultural standard of Quality of Edible Rice Varieties.It has been authorized by the National Crop Variety Committee of the Ministry of Agriculture and Rural Affairs in February 2019.

Pre-Breeding Genetic Diversity Assessment of Tomato(Solanum lycopersicum L.)Cultivars Based on Molecular,Morphological and Physicochemical Parameters

Appropriate knowledge of the parental cultivars is a pre-requisite for a successful breeding program.This study characterized fruit yield,quality attributes,and molecular variations of ten tomato cultivars during three consecutive generations under greenhouse conditions.Peto 86,Castle Rock,and Red Star cultivars showed the highest fruit yield(kg/plant),total phenolic compounds(TPC),and sap acidity.Principal component analysis categorized the evaluated fruit yield into three groups based on their quality attributes.A robust positive correlation appeared among traits inside each group.A positive correlation was likewise noticed between the first and the second groups.However,a negative correlation was detected between the first,the second and the third group.Molecular profiling,using seven inter-simple sequence repeat(ISSR)primers,produced 60 loci,including 49 polymorphic loci.The molecular analysis also pinpointed the highest genetic similarity(0.92)between P73 and Moneymaker,while the lowest genetic similarity(0.46)was observed between Castle Rock and Moneymaker.The cultivars P73 and Moneymaker showed the lowest genetic distance(2.24),while the highest genetic distance(5.92)was observed between Super Marmand and Peto86,on the one hand,and between Castle Rock and Moneymaker,on the other hand.The chemical analysis of fruit sap indicated the highest levels of TPC,total flavonoids,anthocyanin,ascorbic acid and total soluble solids in Peto 86 and Castle Rock cultivars.Phylogeny analysis of tomato cultivars based on morphological and molecular attributes indicated four distinct clades.Peto 86,Castle Rock,and Red star cultivars can be recommended for the tomato hybridization breeding programs in the future,with other tomato cultivars as potentially high-yielding parents.

Key Technology for Virus-free Seed Potatoes Pre-elite Breeding

[Objectives]To establish a breeding system for pre-elite seed potatoes.[Methods]Shoot-tip seedlings were cultured with different medium,and then transplanted in different substrates.They were sprayed with nutrient solutions of different formulas.Potato minitubers were induced.[Results]The medium of MS+2.0 mg/L 6-BA,1.0 mg/L NAA+3%sugar was preferable for potato shoot tip culture.After virus detection,the virus-free potato seedlings were propagated.The medium composed of vermiculite,peat and perlite(1∶3∶1)was recommended for transplanting potato tissue culture seedlings in greenhouse.The three-dimensional spray method was used to produce pre-elite seed potatoes.The full-amount MS nutrient solution could increase the tuber number per plant to 55.Induction of minitubers is a better breeding technology for pre-elite seed potatoes.The optimal medium screened for induction of potato minitubers was MS+(5-7)mg/L 6-BA,with a dark culture duration of about 20 d.[Conclusions]The breeding technology established is suitable for the two-season cultivation areas in Zaozhuang.

Practices and Prospects of Super Hybrid Rice Breeding

The great progress in super rice breeding both in China and other countries has been made in recent years. However, there were three main problems in super rice breeding： 1） the super rice varieties were still rare; 2） most super rice varieties exhibited narrow adaptability; and 3） current breeding theories emphasized too much on the rice growth model, but they were unpractical in guidance for rice breeding. According to the authors＇ experience on the rice breeding, the breeding strategies including three steps （super parent breeding, super hybrid rice breeding and super hybrid rice seed production） were proposed, and the objectives of each step and the key technologies to achieve the goals were elucidated in detail. The super parent of hybrid rice should exhibit excellent performance in all agronomic traits, with the yield or sink capacity reached the level of the hybrid rice control in regional trials. The super hybrid rice combination should meet the following criteria： good rice quality, wide adaptation, lodging resistance, resistance to main insects and diseases, and the yield exceeded above 8% over the control varieties in the national and provincial regional trials. To achieve the goal, the technical strategies, such as selecting optimal combination of the parents, increasing selection pressure, paying more attention to harmony of ideal plant type, excellent physiological traits and all the agronomic traits, should be emphasized. The yield of seed production should reach 3.75 t/ha and 5.25 t/ha for the super hybrid rice combinations derived from early-season and middle-season types of male sterile lines, respectively. The main technologies for raising seed production yield included selecting optimum seed production site, using the male sterile line with large sink capacity and good outcrossing characteristics, and improving the amount of the pollen by intensive cultivation of the male parent. According to the technologies of the three-step breeding on super hybrid rice, two super rice parents, including a male parent 996 and a thermo（photo）-genic male sterile [T（P）GMS] line C815S, were bred. Furthermore, a super early hybrid rice combination, Luliangyou 996, which could be used as a double-season early rice variety in middle and lower reaches of the Yangtze River, China, was bred by using the super rice varlet3, 996 as the male parent, and several hybrid rice combinations with higher yield than control variety in regional trials both of Hunan Province and state were bred with the T（P）GMS line C815S as the female parent.

Rapid generation advance(RGA) in chickpea to produce up to seven generations per year and enable speed breeding

This study was aimed at developing a protocol for increasing the number of generation cycles per year in chickpea(Cicer arietinum L.).Six accessions,two each from early(JG 11 and JG 14),medium(ICCV 10 and JG 16),and late(CDC-Frontier and C 235)maturity groups,were used.The experiment was conducted for two years under glasshouse conditions.The photoperiod was extended to induce early flowering and immature seeds were germinated to further reduce generation cycle time.Compared to control,artificial light caused a reduction in flowering time by respectively 8–19,7–16,and 11–27 days in early-,medium-,and late-maturing accessions.The earliest stage of immature seed able to germinate was 20–23 days after anthesis in accessions of different maturity groups.The time period between germination and the earliest stage of immature seed suitable for germination was considered one generation cycle and spanned respectively 43–60,44–64,and 52–79 days in early-,medium-,and late-maturing accessions.However,the late-maturing accession CDCFrontier could not be advanced further after three generation cycles owing to the strong influence of photoperiod and temperature.The mean total number of generations produced per year were respectively 7,6.2,and 6 in early-,medium-,and late-maturing accessions.These results have encouraging implications for breeding programs:rapid progression toward homozygosity,development of mapping populations,and reduction in time,space and resources in cultivar development(speed breeding).

Cotton Breeding in Xinjiang and Its Intellectual Property Protection

In 2021,Xinjiang's cotton output was 5.129 million t,accounting for 89.50%of China's total.The autonomous region produces high-quality long-staple cotton,natural colored cotton,fine-staple cotton(upland cotton),organic cotton,etc.The southern Xinjiang cotton area is one of the three major long-staple cotton(island cotton)producing regions in the world.This paper introduced the history of cotton planting and breeding in Xinjiang from the aspects of cultural relics records,history of entering Xinjiang,historical achievements of breeding and breeding leaders.We studied the intellectual property protection of cotton breeding in the autonomous region from the aspects of biological genetic resources,invention patents,utility model patents and new plant varieties,analyzed the six main problems existing in cotton breeding and its intellectual property protection,and discussed the tactics for cotton breeding and its intellectual property protection in Xinjiang under the strategy of strengthening the country with intellectual property.Eight suggestions in response to the Xinjiang cotton incident were also put forward,including establishing a Xinjiang national cotton germplasm nursery,protecting biological genetic resources,and strengthening the protection of creative intellectual property rights in the field of breeding to escort technological innovation in the cotton seed industry.

Breeding and Application of Guidan 903,a New High-yield and Good-quality Maize Variety

To meet the demand of maize production in Guangxi and even the southwest region of China and realize the upgrading and undating of maize varieties which will continuously improve the yield and quality of maize,a new big-ear maize variety Guidan 903 with high yield,stable yield and good quality was established by the Maize Research Institute of Guangxi Academy of Agricultural Sciences with two self-selected inbred line GRL17349 and GRL21191 as female and male parents seperately.The average yield of this variety were 7429.5 and 7000.5 kg/hm^(2)in Guangxi Maize Regional Trial and Production Test respectively,which increased by 6.3%and 5.6%than the control(Guidan162).It was approved by Guangxi Zhuang Autonomous Region Crop Variety Certification Committee in June 2020(Approval No.Gui sheng yu 2020083).Determined by the Cereal Quality Supervision and Testing Center of Ministry of Agriculture and Rural Affairs(Bejjing),the grain bulk density,ratio of crude protein,crude fat,crude starch and lysine of Guidan 903 were 782 g/L,9.41%,6.19%,71.45%,0.35%respectively.This variety has the characterisics of strong resistance to collapse and disease,good quality,high and stable yield and wide adaptability.Furthermore,its seed yield is high with easy production technology and low cost.

Breeding and Cultivation Technique of Ditian 6

Ditian 6 is super sweet corn hybrid. Its parents are inbred line 201-2 and 769 respectively. It was certificated by Variety Certification Committee of Shanxi Province in 2013. Ditian 6 participated in regional trials of Shanxi Province in 2010 and 2011. The average fresh ear yield is 14257. 5 kg / ha. Its growth period is 81 d,belonging to the early variety. It has obvious advantages if it is early cultivated. The kernel is yellow,and the quality reaches a high level. In the early or late market,it has significant economic benefits. The variety has strong resistance to disease and adversity,with wide adaptability,high and stable yield. It can be planted in the areas where accumulated temperature is above 2300℃.

Report on the Breeding of Dahen 799 Broilers

[Objectives]This study was conducted to improve the production efficiency of dark-shank partridge-like plumage high-quality broilers and ensure animal welfare,so as to meet the development needs of China’s yellow-feather broiler industry.[Methods]Sichuan Animal Science Academy and Sichuan Dahen Poultry Breeding Co.,Ltd.formed a joint breeding research team.The team bred Dahen 799 broiler complete set line with local chicken breeds as the main material and improving production efficiency,stabilizing meat quality and flavor and achieving autosexing of chicks as the main breeding goals by modern poultry breeding technologies,after 10 years and 8 generations.[Results]The Dahen 799 broiler complete set line was approved by National Commission of Livestock and Poultry Genetic Resources in December 2020.The 66-week-old egg production of the breed reached 189 eggs.For the commercial generation,cocks and hens showed 10-week-old weights of 2668 and 2269 g,respectively;the feed conversion ratio was 2.26-2.35;the survivability was 96.7%-97.2%;and the average intramuscular fat contents of cocks and hens were in the range of 1.8%-2.1%,and the inosinic acid contents were in the range of 2.3-3.2 mg/g.The production performance and meat flavor of Dahen 799 broilers were better than Dahen 699 broilers,Sichuan mountainous bone-black chickens and two other social breeds.Compared with Sichuan mountainous bone-black chickens,the egg production at the age of 66 weeks increased by 47 eggs;the average weight of cocks and hens of the commercial generation at 10 weeks increased by 45.21%;and the autosexing rate of chicks of the commercial generation reached 99.3%.[Conclusions]Dahen 799 broilers have the advantages of good production performance,high feed conversion ratio and excellent meat flavor and the characteristic of autosexing which other breeds do not have,and can fully meet the industrial development needs of dark shanks and partridge-like plumage broilers.

关于吉林省直播稻育种的几点思考

因直播稻与移栽稻的播期及栽培措施等存在不同,两者在抽穗期、产量及产量构成因素等诸多农艺性状上均存在显著差异。为更好提升直播稻产量并培育直播配套品种,笔者从直播稻的生育期及物候期、种子应具备的特征特性、产量结构及品种农艺性状、品种抗性、育种体系等方面提出几点思考。

优质玉米新品种龙单246的选育及高产制种技术

为了促进玉米新品种龙单246在适宜种植区域内示范推广,本文简要介绍了龙单246亲本来源及选育过程、品种特征特性、产量表现、栽培技术要点及高产制种技术。龙单246是由黑龙江省农业科学院玉米研究所高产遗传育种研究室2015年以改良系H286为母本、改良系LX461为父本杂交选育而成。在2023年通过黑龙江省农作物品种审定委员会审定(审定编号:黑审玉2023L0044)。2020-2021年参加黑龙江省龙科玉米科企联合体区域试验,平均产量9901.2 kg·hm^(-2),比对照品种禾田4号或东农254平均增产9.0%;2022年参加黑龙江省龙科玉米科企联合体生产试验,平均产量10752.3 kg·hm^(-2),较对照东农254平均增产7.0%。龙单246具有粮质好、综合抗性强、丰产性好等特点。

山东省水产种业高质量发展战略研究

山东是我国渔业大省,肩负着打造“蓝色粮仓”,构筑“海上田园”的重要使命。山东省水产种业的高质量发展,对于贯彻落实“大食物观”,保障我国水产品的持续、多样供给具有重要意义。本文基于文献分析、实地调研等方式,系统地梳理了山东省水产种业发展现状,指出了山东省水产种业在顶层设计规划、优异种质资源收集与保存、高效育种技术创新与应用、突破性新品种培育以及种业龙头企业打造等方面存在的不足,有针对性地提出了山东省养殖鱼类、贝类、虾蟹、参藻种业以及种业经济发展的远景目标、重点任务和行动建议,以期为山东省水产种业高质量发展提供参考。

早熟高产杂交水稻组合两优7871的选育及其高产栽培和制种技术

两优7871是由178S和R71杂交选育的杂交水稻品种,具有早熟、抗倒伏、优质、高产和稳产等特点。本文总结分析了该品种的选育过程、特征特性、高产栽培及制种技术,该品种在2016—2017年长江中下游区域试验中,全生育期130 d,平均产量9.51 t/hm^(2),外观品质优,适口性、抗病性较好;其高产栽培注重培育壮秧,控制无效分蘖,争取有效穗数,促大穗,提高结实率,重点防治稻瘟病、稻飞虱等;制种技术要点包括合理安排播差期,培育壮秧,合理密植,加强田间管理和巧喷赤霉酸生长调节剂等。研究结果为该品种在长江中下游作为一季中稻、麦茬直播稻和再生稻种植提供参考。

基于文献分析的罗汉果产业技术研究进展

为助力广西罗汉果(Siraitia grosvenorii)特色产业高质量发展,本文以国内外图书、期刊学术论文、学位论文、会议论文、专利技术、标准技术、科技成果登记等技术文献分析罗汉果产业技术研究现状,以科技奖励获奖情况分析行业技术的“尖锋”发展情况,从罗汉果的品种选育与繁育、种植栽培、深加工技术、应用开发等方面分析近3年的罗汉果行业热点,全方位、多角度、有针对性地综述罗汉果产业技术研究进展,并分析罗汉果产业技术的不足之处,以期为广西罗汉果产业的研究方向和发展规划提供参考。

中波紫外线辐照对甜玉米种子萌发的影响及转录组分析

【目的】研究中波紫外线(UV-B)辐照处理对甜玉米种子萌发及相关基因表达的影响,为解析UV-B辐照促进种子活力的分子机理奠定基础。【方法】以甜玉米自交系T28种子为材料,设置0(CK),0.5,1,2,4和8 h共6个不同时长的UV-B辐照处理,对处理和对照(CK)种子萌发相关的表型指标、生理指标进行分析,同时借助转录组测序技术筛选促进玉米种子萌发的差异表达基因。【结果】UV-B辐照处理1 h时甜玉米自交系T28种子的发芽率最高,发芽势、发芽指数和活力指数随着UV-B处理时间的延长均呈先上升后下降的趋势,且在UV-B辐照处理1 h时达到最高。UV-B辐照处理1和2 h的甜玉米种子萌发72 h后,萌发种子的CAT、POD活性和游离脯氨酸含量均高于CK。对0(CK),1和2 h辐照处理下的差异表达基因进行趋势表达分析,获得8个不同趋势的基因集profile(0-7),其中profile2中1 716个转录本表达量呈先下降后上升趋势,profile5中919个转录本表达量呈先上升后下降趋势。GO富集分析表明,在生物过程、细胞组分、分子功能类别中,profile2基因集中富集最显著的分别为蛋白磷酸化、膜整体组件、转移酶活性和转移己糖基,profile5基因集中富集为翻译、核糖体、核糖体的结构组分。KEGG富集分析发现,profile2基因集中显著富集的通路主要注释在苯丙素类生物合成、次生代谢物的生物合成、代谢途径等;profile5基因集中显著富集的通路为淀粉和蔗糖代谢、氧化磷酸化及蛋白酶体。淀粉和蔗糖代谢通路中13个基因与各样本表达量聚类分析表明,在处理1 h样本中这些基因的表达显著上调。【结论】UV-B处理可以提高甜玉米种子的活力,处理时长1 h的效果最显著,推测不同时长处理下的差异表达基因与种子活力密切相关。

小麦穗发芽抗性机制及抗性育种研究

穗发芽是禾本科作物籽粒在收获前于高湿环境下的穗上发芽现象,严重影响小麦的产量与品质。种子休眠水平是影响小麦穗发芽抗性的主要因素,而往往驯化作物的籽粒休眠水平低,导致栽培小麦普遍比其野生祖先种更易发生穗发芽。小麦穗发芽主要受外源环境(温度、湿度等)和内源植物激素(GAs、ABA、IAA、MeJA、ET、BR)的调控。已鉴定出一批抗穗发芽材料,并克隆了一系列调控穗发芽抗性的关键基因,如PM19、MFT、MKK3、Myb10-3D、Vp1等。通过分子标记辅助选择、人工合成小麦和CRISPR/Cas9基因编辑技术,已成功创制了抗穗发芽小麦新材料。本文综述了小麦穗发芽抗性的遗传机制及抗性育种研究的最新进展,未来仍需继续挖掘关键穗发芽抗性基因,以生物育种的方法培育抗穗发芽小麦新品种。

日本落叶松种子园和优树自由授粉家系选择与利用研究

在甘肃小陇山沙坝落叶松/云杉良种基地,采用完全随机区组试验设计,对25个种子园的自由授粉家系和30个优树自由授粉家系在日本落叶松采伐迹地进行了更新造林试验,应用SPSS16.0和ASReml v3.0对造林9年生数据进行了统计分析。结果表明:不论是种子园自由授粉家系还是优树自由授粉家系试验林,树高、胸径、材积等性状家系间具有丰富的遗传变异,家系不同性状间具有显著的相关性,表型变异系数和遗传变异系数最大的是材积。种子园自由授粉家系试验林树高、胸径、材积的家系遗传力和单株遗传力为0.492、0.680、0.694和0.093、0.162、0.171,优树自由授粉家系试验林树高、胸径、材积的家系遗传力和单株遗传力为0.560、0.544、0.496和0.128、0.109、0.096,家系性状遗传力大于单株遗传力,家系性状受到中等以上的遗传控制,家系选择潜力大。根据种子园自由授粉家系亲本育种值指导初级无性系种子园去劣疏伐、改建1.5代种子园。以材积为主要选择指标,兼顾胸径、树高,在家系择基础上配合单株选择,从种子园自由授粉家系和优树自由授粉家系各选择20个优良单株构建高阶生产群体,高阶生产群体的预期遗传增益和现实增益分别达到25.74%、22.85%和122.59%、154.22%。从种子园自由授粉家系选择的50个单株作为构建遗传改良群体的应用材料,将优树自由授粉家系选择的45个单株作为育种群体的补充材料,构建遗传品质不断提高和遗传基础不断拓展的改良群体应用材料。

北京市草莓育苗模式及发展建议

随着草莓需求量的日益增加,对草莓的种植技术提出了更高的要求,尤其是育苗技术,育苗技术的完善是草莓产业不断提升的重要环节。本文分析了北京市草莓育苗产业发展现状,介绍了主要育苗模式及应用技术;提出除发挥北京市自身优势外,还应充分利用外埠冷凉地区条件进行优质草莓种苗繁育工作,健全标准化生产体系,形成“政府+科研单位+企业”的育苗管理模式,提升育苗水平,保障北京地区优质种苗供应。