湘杂棉品种杂交一代优化管理

湖南省棉花科学研究所（以下简称湖南棉科所）从1995-2008年共选育出湘杂棉1号至19号共计19个形态各异、不同特色的系列品种,在湖南、湖北、河南、江西、江苏、安徽、浙江等省累计推广面积达267万hm^2,创经济效益数亿元。因湘杂棉品种杂交一代制种（以下简写为F1）开发具有可观的商业利润空间，与湖南棉科所签约合作参与F1开发的省内外种子开发商有10余家。湘杂棉品种开发是一个系统工程，     

浙江省农作物现代种业创新园建设实践与思考

农作物现代种业创新园是集聚种业创新资源要素,实现种业集约高效发展的重要载体,建设农作物现代种业创新园也是推进现代种业发展的重要手段。通过对浙江省目前在建或初步建成的5个种业创新园现状进行全面调查,总结分析种业创新园建设的主要特点和优势,梳理了规划和建设中存在的问题,并从建设目标、建设标准、建设内容和保障措施等4个方面提出了推进浙江省农作物现代种业创新园建设的思路。     

种质资源保护和育种创新现状及发展对策——以湖南和海南两省为例

自实施第3次全国农作物种质资源普查行动以来,湖南和海南两省积极开展种质资源普查工作,相继出台了促进现代种业发展的相关政策法规,农业种质资源保护和育种创新工作取得了一定成绩。在总结两省基本做法的基础上,分析了目前两省种业发展面临的挑战,从强化顶层设计、加强种质资源保护、建立健全现代种业创新体系、提高商业化育种能力、完善落实种业知识产权保护和提升种业发展支撑保障水平6个方面提出了发展对策,为我国种质资源保护及育种创新发展提供参考。     

陈晓华：推进种业科技创新

由农业部、科技部、湖南省人民政府联合主办的第一届中国杂交水稻大会在湖南长沙开幕。农业部副部长陈晓华在致辞中强调,转变农业发展方式,必须把种业科技创新摆在更加突出的位置,加大科研攻关、技术推广和人才培养力度,大力推进农业科技进步,促进现代种业发展,为粮食增产、农民增收和农业可持续发展提供强大科技支撑。     

国审湘杂棉11号F1配套高产栽培技术

湘杂棉11号（原名湘S-26）是湖南省棉花科学研究所、中国农业科学院生物技术研究所、北京中农种业共同选育．是著名棉花育种家周世象研究员继湘杂棉3号、湘杂棉8号之后选育出的又一高产、优质、多抗的杂交棉花新品种．也是湖南省选育的第1个通过国家审定的双价转基因抗虫杂交棉品种。该品种具有大桃、品质极优、高产稳产、抗虫抗病、中早熟易栽培、结铃性强且集中、吐絮畅易采摘、通透性好、抗逆性强、不早衰等特点。2006—2007年,虽然遭受强台风、暴雨高温干旱等不良气候条件的频繁袭击．     

晚稻新品种——威优8号

威优8号是湖南科裕隆种业有限公司选育成功的水稻新品种,品种来源为V20A×湘恢8,该品种具有优质、高产的特点,2011年通过湖南省农作物品种审定委员会审定（湘审稻2011038）。     

两系优质中籼杂交新组合呈两优464

呈两优 464 是湖南洞庭高科种业股份有限公司利用湖南农业大学选育的优质高配合力两系不育系呈 391S 为母本,以湖南洞庭高科种业股份有限公司选育的高配合力恢复系岳恢 464 为父本配组选育的优质、稳产中籼杂交水稻新组合;该组合生育期适宜、抗性好、产量稳、米质优。 2020-2021 年参加湖南省湘种联合体中籼迟熟组区域试验及生产试验, 2022 年通过湖南省农作物品种审定委员会审定（湘审稻20220024 ）。     

科技创新与现代农作物种业发展

科技兴农,良种先行。当今世界,种业科技创新已经成为农业科技创新的前沿和关键。本文从科技创新与现代种业发展之间关系入手,对世界和我国的种业科技发展现状及存在的问题进行了深入分析,并就如何应对国际种业的挑战,加快我国现代农作物种业发展提出了一些思考与建议。     

宁波市七大种业发展经验及创新发展建议

宁波市把种业作为推动现代都市农业发展的主要产业,以强化政策扶持、创新育种机制、培育种业龙头、构建产业联盟为抓手,形成了“水稻与瓜菜两大核心,大黄鱼、青蟹两个水产,大白鹅、红美人、黑猪三个地方特色”的七大拳头种业。通过围绕现阶段种业发展短板弱项,提出宁波现代种业高质量发展、创新发展建议。     

北京现代种业产业链创新发展研究

当前,种业竞争是全产业链的竞争,种业竞争力是基于整个产业链高度控制的市场影响力。北京是我国种业之都,面临种业 “战略发展的转折期”,重塑北京种业产业链已迫在眉睫。本文通过研究北京现代种业产业链创新发展存在的问题,提出产业链创新发展的路径,以其为北京种业深入改革提供参考。     

Dry matter and nitrogen accumulation and residues of oil and protein crops

Oil and protein crops are of growing importance in cropping systems. This study was carried out to compare oil crops of linseed, rapeseed, sunflower and protein crops of faba bean and white lupin for grain production, residual plant dry matter and nitrogen. Two field experiments with either oil or protein crops were conducted in 1993 and 1994, respectively. Total dry matter production, grain yield, residues, N concentrations and mineral N in the soil were measured. Dry matter production and distribution as well as N uptake and residues varied greatly among species and between years. In 1993, oil crops gave up to 3 t ha⁻¹ grain and 16 t ha⁻¹ residues with sunflower, while in 1994 up to 5 and 11 t ha⁻¹, respectively, were recorded with winter rape. Protein crops showed an opposite reaction in years. Nitrogen uptake and residual N amounts were correlated with dry matter production. Plant residues of oil crops contained 20–140 kg N ha⁻¹; those of protein crops up to 80 kg N ha⁻¹. Despite the variation of residual plant N the variability of mineral N in the soil at harvest was hardly influenced by crops and amounted to only 20–50 kg NO⁻₃-N ha⁻¹.     

Ethanol vapor and saprophytic yeast treatments reduce decay and maintain quality of intact and fresh-cut sweet cherries

The objective of this study was to evaluate the use of an ethanol vapor release pad and a saprophytic yeast Cryptococcus infirmo-miniatum (CIM) to reduce decay and maintain postharvest quality of intact or fresh-cut sweet cherries (Prunus avium) cv. Lapins and Bing. Intact or fresh-cut fruit were packed in perforated clamshells (capacity 454 g) and stored at 1, 10 or 20 °C for up to 21, 14 and 8 d, respectively. For ethanol treatment, a pad made with silica gel powder containing 10 g ethanol and covered with perforated film, which allows ethanol vapor to diffuse gradually, was attached to the upper lid of the clamshells. Ethanol treatment caused accumulation of ethanol in the packaging headspace, about 10 μL L⁻¹ with little change within 14 d at 1 °C, 23 μL L⁻¹ at d 1 and decreased to 15 μL L⁻¹ at d 10 at 10 °C, and 26 μL L⁻¹ at d 1 and decreased to 13 μL L⁻¹ at d 3 at 20 °C. Ethanol content in fruit was less than 9 mg kg⁻¹ in all the control fruit, and increased to 16, 34 and 43 mg kg⁻¹ in ethanol-treated fruit at 1, 10 and 20 °C, respectively. Nonetheless, a sensory taste panel did not perceive any flavor difference from the ethanol treatment. The ethanol treatment retarded softening, darkening, and acid decrease in fruit as well as discoloration of the stems, and extended shelf-life of intact cherries. Ethanol reduced brown rot (Monilinia fructicola) in fresh-cut cherries stored at 20 °C, but not at 1 and 10 °C. A pre-packaging dip in CIM completely controlled brown rot in inoculated fresh-cut cherries stored at 1 °C, and in naturally infected cherries at 20 °C.     

Juvenile phase and growth of apple and pear seedlings

It was investigated whether and to what extent the duration of the juvenile phase of pear and apple seedlings is related to their vegetative growth. The juvenile phase was defined as the period in years that the seedling remains vegetative; the trunk diameter served as a measure of vegetative vigour. The following observations were made:

1. 1)

   A significant negative correlation exists between the duration of the juvenile phase and the vigour of the seedling (as measured by trunk diameter).

2. 2)

   Environmental conditions with respect to weather, soil and cultural practices which promote or restrict growth, tend to shorten or lengthen the juvenile phase accordingly by their influence on the time required for the attainment of a certain minimum size which at least partly determines the attainment of the flowering condition.

3. 3)

   The weak rootstock M. IX significantly accelerated the onset of flowering of apple seedlings by about 1 1/2 years; this rootstock appears to combine a retarding effect on growth with a specific influence on flowering.

     

Natural and experimental hybrids of ryegrasses and meadow fescue

1. 1.
   Chromosome numbers, male and female fertility and morphological characters were studied on about 90 plants from each of two natural populations of hybrids between Lolium perenne and Festuca pratensis.     
   
   

Fourteen years of applying zero and conventional tillage,crop rotation and residue management systems and its effect on physical and chemical soil quality

Soil management systems may negatively affect the quality of the soil. Policymakers and farmers need scientific information to make appropriate land management decisions. Conventional (CT) and zero tillage (ZT) are two common soil management systems. Comparative field studies under controlled conditions are required to determine the impact of these systems on soil quality and yields. The research presented studied plant and soil physical and chemical characteristics as affected by different agricultural management practices, i.e. ZT and CT, cropped with continuous wheat or maize in monoculture (M) or in a yearly rotation (R) of these two crops, either with residue retention (+r) or without residues retention (?r), in an experimental field in the Transvolcanic Belt of Mexico after 14 years. The dominant factors defining soil quality were organic C, total N, moisture, aggregate stability, mechanical resistance, pH and EC. The principal component combining the variables organic C, total N, aggregate stability and moisture content showed the highest correlations with final yield (R = 0.85 for wheat and 0.87 for maize).After 14 years of continuous practice, ZTM + r and ZTR + r had the best soil quality and produced the highest wheat and maize yields of average 2001–2004 (6683 and 7672 kg ha^?1 and 5085 and 5667 kg ha^?1, respectively). Removing the residues, i.e. treatments ZTM ? r with maize (average 2001–2004: 1388 kg ha^?1) and ZTR ? r and CTR ? r with wheat (average 2001–2004: 3949 and 5121 kg ha^?1), gave the lowest yields and less favourable soil physical and chemical characteristics compared to the other practices. It was found that zero tillage with residue retention is a feasible management technology for farmers producing maize and wheat in the agro-ecological zone studied, resulting in a better soil quality and higher yields than with the conventional farmer practice (maize monoculture, conventional tillage and residue removal).     

Detecting and estimating segregation distortion and linkage between glufosinate tolerance and blackleg resistance in Brassica napus L.

Summary The segregation and linkage between glufosinate (transgenes ‘Rf3’ and ‘T177’) and blackleg resistance genes in canola (Brassica napus L.) were assessed using F₁ microspore-derived doubled haploid (DH) populations from four crosses including reciprocals, two involving the transgene ‘Rf3’ and the other two involving the transgene ‘T177’. To relax the assumption of no segregation distortion required for the conventional analysis of segregation and linkage, we employed Bailey's analysis that allows detecting segregation distortion at linked loci. The significant departures from the 1:1 segregation were detected in the crosses involving the transgene ‘T177’ but not in the crosses involving the transgene ‘Rf3’. The apparent deficit of the herbicide tolerant DH lines in the crosses with the transgene ‘T177’ is likely due to differential selection against the gametes carrying ‘T177’ during microspore culture. The linkage was strong between blackleg resistance and the transgene ‘Rf3’ but weak or absent between blackleg resistance and the transgene ‘T177’, suggesting that the two transgenes are probably inserted into distant regions of the genome. The observed linkage offers an opportunity to develop new canola cultivars with both glufosinate tolerance conferred by transgene ‘Rf3’ and blackleg resistance.     

Tillage,cover crops,and nitrogen fertilization effects on soil nitrogen and cotton and sorghum yields

Sustainable soil and crop management practices that reduce soil erosion and nitrogen (N) leaching, conserve soil organic matter, and optimize cotton and sorghum yields still remain a challenge. We examined the influence of three tillage practices (no-till, strip till and chisel till), four cover crops {legume [hairy vetch (Vicia villosa Roth)], nonlegume [rye (Secaele cereale L.)], vetch/rye biculture and winter weeds or no cover crop}, and three N fertilization rates (0, 60–65 and 120–130 kg N ha⁻¹) on soil inorganic N content at the 0–30 cm depth and yields and N uptake of cotton (Gossypium hirsutum L.) and sorghum [Sorghum bicolor (L.) Moench]. A field experiment was conducted on Dothan sandy loam (fine-loamy, siliceous, thermic, Plinthic Paleudults) from 1999 to 2002 in Georgia, USA. Nitrogen supplied by cover crops was greater with vetch and vetch/rye biculture than with rye and weeds. Soil inorganic N at the 0–10 and 10–30 cm depths increased with increasing N rate and were greater with vetch than with rye and weeds in April 2000 and 2002. Inorganic N at 0–10 cm was also greater with vetch than with rye in no-till, greater with vetch/rye than with rye and weeds in strip till, and greater with vetch than with rye and weeds in chisel till. In 2000, cotton lint yield and N uptake were greater in no-till with rye or 60 kg N ha⁻¹ than in other treatments, but biomass (stems + leaves) yield and N uptake were greater with vetch and vetch/rye than with rye or weeds, and greater with 60 and 120 than with 0 kg N ha⁻¹. In 2001, sorghum grain yield, biomass yield, and N uptake were greater in strip till and chisel till than in no-till, and greater in vetch and vetch/rye with or without N than in rye and weeds with 0 or 65 kg N ha⁻¹. In 2002, cotton lint yield and N uptake were greater in chisel till, rye and weeds with 0 or 60 kg N ha⁻¹ than in other treatments, but biomass N uptake was greater in vetch/rye with 60 kg N ha⁻¹ than in rye and weeds with 0 or 60 kg N ha⁻¹. Increased N supplied by hairy vetch or 120–130 kg N ha⁻¹ increased soil N availability, sorghum grain yield, cotton and sorghum biomass yields, and N uptake but decreased cotton lint yield and lint N uptake compared with rye, weeds or 0 kg N ha⁻¹. Cotton and sorghum yields and N uptake can be optimized and potentials for soil erosion and N leaching can be reduced by using conservation tillage, such as no-till or strip till, with vetch/rye biculture cover crop and 60–65 kg N ha⁻¹. The results can be applied in regions where cover crops can be grown in the winter to reduce soil erosion and N leaching and where tillage intensity and N fertilization rates can be minimized to reduce the costs of energy requirement for tillage and N fertilization while optimizing crop production.     

Genetic analysis of presence and absence of lint and fuzz in cotton

Cotton fibre mutants that were fuzzless and/or lintless were crossed with each other and a normal genotype (fuzzy, linted) to produce F₂ and BC₁ generations. F₂ segregation ratios from the cross of fuzzless‐lintless × fuzzy‐linted, for fuzzy‐linted, fuzzless‐linted and fuzzless‐lintless were 45 : 15 : 4. From the cross of fuzzless‐lintless × fuzzy‐linted, the F₂ segregation ratios were 9 : 39 : 16 whereas the BC₁F₁ segregation ratios from the F₁ backcrossed to fuzzless‐lintless were 1 : 3 : 4. These data suggest that the presence or absence of lint and fuzz are controlled by the interaction of four gene loci on non‐homologous chromosomes. We designate these loci as N₁, N₂, Li₃ and Li₄, where N₁ N₁ confers the presence of fuzzy, N₂N₂ confers inhibition of fuzzy initiation and development, and duplicate gene pairs, Li₃Li₃ and Li₄Li₄, determine the presence of lint. Homozygosity for li₃li₃ and li₄li₄ might also inhibit fuzz from development. In other words, they were recessive epistatic to fuzz genes.     

Grain yield and other traits of tall and dwarf isolines of modern bread and durum wheats

Near-isogenic Rht lines of ten modern bread wheat (Triticumaestivum L.) and six durum wheat (T. turgidum L.) cultivars weredeveloped and evaluated in replicated trials under three soil moisturetreatments for two years in northwestern Mexico. The three soil moisturetreatments were created by providing one, two or six irrigations during eachcrop season. Grain yield and other traits were measured for each line ineach trial. Mean grain yields of short and tall T. aestivum or T.turgidum isolines were similar in the lowest yielding environment whenmean grain yields (0% grain moisture) of T. aestivum and T.turgidum were 2,232 and 1,870 kg ha^-1, respectively. Mean grainyield of dwarf T. aestivum was significantly higher than that of tallgenotypes in another five trials with moderate to high yields. Theperformance of dwarf and tall T. turgidum isolines was unpredictablein moderate yielding trials, and the dwarf isolines yielded significantly morein trials that received six irrigations. Given that the tall isolines producedsignificantly more straw than their shorter counterparts, cultivation of tallwheats may be beneficial in semiarid environments where farmers' yields areclose to 2.5 t ha^-1 or lower, and straw has value.     

Cytogenetics and morphology of the pentaploid hybrid between Brassica napus and Orychophragmus violaceus and its progeny

A pentaploid hybrid plant (2n= 50, AACCO) between Brassica napus (AACC) and Orychophragmus violaceus (OO) showed matroclinous morphology and some patroclinous characters. Cloned progenies were mixoploid, consisting of various cells with 38–53 chromosomes, half of the cells with 50 chromosomes. The 50 chromosomes were mainly paired as 25 bivalents and segregated as 25:25 or 22:28; many other segregations were observed in some cells. Progenies produced by selfing had 38–47 chromosomes. Plants with 38 chromosomes were cytologically stable; in all other plants the chromosome number of individual cells varied between the genotype-specific maximum number and 38, indicating loss of chromosomes during mitosis. The mixoploid plants with 44 chromosomes mainly produced two kinds of mixoploid progenies with 44 and 41 chromosomes, respectively. All plants with 2n= 38 had the same morphology as the parental B. napus and were normal in fertility. These chromosome pairings and segregations in the pentaploid and its progeny support the hypothesis that O. violaceus is a natural polyploid species with a basic chromosome number of 3.