马铃薯晚疫病药剂拌种试验初报

经过田间药效试验,筛选出10％嘧菌酯20ml对水3kg拌种马铃薯80kg药剂配方,具有促苗早发、防病增产作用。可有效预防马铃薯晚疫病病害,防效高达86．7％,增产率达到64．7％,病情指数为5．1％,该处理与其他处理在0．05和0．01水平下差异均达到显著和极显著水平,生产上可大面积推广应用。     

不同抗早衰剂配方对杂交早稻后期叶片衰老的影响

以后期易早衰的春光2号为试验材料,研究了不同抗早衰剂对杂交早稻后期叶片衰老的影响。结果表明:施用不同抗早衰剂均能不同程度地提高功能叶的叶绿素含量、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、过氧化物酶(POD)活性和维生素C含量,降低功能叶细胞膜透性、丙二醛(MDA)含量和活性氧自由基(O2-.)产生速率,明显提高早稻的结实率和千粒重,延缓早稻的衰老,达到增产的效果。在4个不同抗早衰剂配方中,以抗早衰剂4号的效果最好,比喷清水对照增产10.0%,抗早衰剂1号次之,比喷清水对照增产9.0%,达到极显著或显著差异。     

桐城市8个双晚新品种的比较试验

20 0 0年对 8个新引进杂交晚稻组合的经济性状、产量表现进行了比较 ,筛选出适合桐城地区种植的“两高一优”新的杂交双晚组合。试验结果分析表明“两优倍胜”、“培杂茂三”是值得大面积推广的优良杂交双晚组合。     

2014年晚稻新品种生产试验

为了选择适宜上杭县种植的优质杂交晚稻品种,2014年引进赣优673、中浙优86、福龙两优1031、恒丰优387、广8优673、安优18等6个新品种进行生产试验,结果表明:广8优673、福龙两优1031、安优18、赣优673等4个品种比对照品种宜优673增产;建议广8优673、福龙两优1031和安优18等3个品种扩大试种,赣优673和恒丰优387等2个品种继续参试。     

特旱年陆良迟栽水稻生态性状分析

[目的]分析大田迟栽水稻的生长性状及产量形成特征.[方法]观测迟栽水稻大田期的生长特性,与正常移栽水稻进行对比分析,找出迟栽水稻与正常情况下移栽水稻的异同.[结果]迟栽水稻与正常移栽水稻相比,表现为分蘖异常、早穗现象突出、后期低温冷害严重;迟栽水稻分蘖能力差异大、分蘖时期长、分蘖茎生长异常;发育期不一致,早穗现象严重;抽穗开花期时间过长、生育期延迟,易受后期低温冷害危害,造成大面积减产.[结论]该研究为今后应对气候变化、特殊年型的水稻生产提供科学的决策依据.     

土壤酸化对晚稻产量的影响及品种耐酸性比较

以23个晚稻品种为材料,在湖南省长沙县进行大田试验,研究土壤酸化对晚稻产量的影响,并比较了品种耐酸性差异。结果表明：①各品种在普通大田产量为5226.6～9202.1 kg/hm2,在酸化大田产量为3643.2～7714.8 kg/hm2,品种间差异显著;②与普通大田比较,酸化大田条件下岳优6135、华优18、金优284和Ⅱ优46产量提高,增幅为3.24%～26.33%,其他品种产量均下降,降幅为2.04%～56.79%;③根据产量变化的显著性,供试品种可分为3种类型,五丰优 T025、荆楚优148、岳优6135、深优9586、湘丰优103、中优288、农香18、汕优432、Ⅱ优6号和中9A/R10402属酸性敏感型,五优308、准两优608、丰源优227、丰优1167、丰源优299、T优272、中9A/R9963属酸性中间型;岳优9113、金优284、深优9588、华优18、Ⅱ优46和Ⅱ优3027属酸性迟钝型。     

SSR analysis of cultivated groundnut (Arachis hypogaea L.) germplasm resistant to rust and late leaf spot diseases

Cultivated groundnut (Arachis hypogaea L.) is an agronomically and economically important oilseed crop grown extensively throughout the semi-arid tropics of Asia, Africa and Latin America. Rust (Puccinia arachidis) and late leaf spot (LLS, Phaseoisariopsis personata) are among the major diseases causing significant yield loss in groundnut. The development of varieties with high levels of resistance has been constrained by adaptation of disease isolates to resistance sources and incomplete resistance in resistant sources. Despite the wide range of morphological diversity observed in the cultivated groundnut gene pool, molecular marker analyses have thus far been unable to detect a parallel level of genetic diversity. However, the recent development of simple sequence repeat (SSR) markers presents new opportunities for molecular diversity analysis of cultivate groundnut. The current study was conducted to identify diverse disease resistant germplasm for the development of mapping populations and for their introduction into breeding programs. Twenty-three SSRs were screened across 22 groundnut genotypes with differing levels of resistance to rust and LLS. Overall, 135 alleles across 23 loci were observed in the 22 genotypes screened. Twelve of the 23 SSRs (52%) showed a high level of polymorphism, with PIC values ≥0.5. This is the first report detecting such high levels of genetic polymorphism in cultivated groundnut. Multi-dimensional scaling and cluster analyses revealed three well-separated groups of genotypes. Locus by locus AMOVA and Kruskal–Wallis one-way ANOVA identified candidate SSR loci that may be valuable for mapping rust and LLS resistance. The molecular diversity analysis presented here provides valuable information for groundnut breeders designing strategies for incorporating and pyramiding rust and late leaf spot resistances and for molecular biologists wishing to create recombinant inbred line populations to map these traits.E.S. Mace and D.T. Phong contributed equally to this work.     

Tomato late blight (Phytophthora infestans) in Uganda

A survey on the tomato late blight situation and current practices for disease management was carried out in Uganda using an informal structured questionnaire approach. Ten districts from different agroclimatic zones were selected for the survey. Phytophthora infestans isolates from tomatoes were obtained from the zones and only the A1 mating type was recovered. Tomato cultivation is practised year-round. The major commercial varieties grown, Moneymaker, Marglobe, Heinz and Roma, were susceptible to late blight. Late blight and bacterial wilt ( Pseudomonas solanacearum ) were the major diseases, with bollworm ( Helicoverpa armigera ) and thrips ( Thrips spp .) the major insect pests. Fungicides, mostly mancozeb, were the predominant control method used by farmers. Sanitation is practised by some farmers, but only in association with fungicides, to control late blight. Plant nutrition is not perceived as playing a major role in late blight management. Problems associated with pesticides and poor marketability were identified as major constraints to tomato production in Uganda.     

晚冰期以来青藏高原东北缘人类的迁移与扩散

利用考古遗迹、年代和区域DEM数据,采用GIS方法,综合分析了晚冰期以来,人类在青藏高原东北缘的迁移与扩散。结果表明：16～6 kaBP人类活动的足迹已遍布青藏高原东北缘,早期人类活动没有固定的聚落,表现为高度流动、长距离、大范围的迁移特征;晚期则实现了半定居。末次冰消期生活在黄土高原西端较低海拔的人群沿着黄河谷地进入高原,到达海拔2 600 m的共和盆地,并以该盆地为枢纽,向北于14 kaBP进入海拔3 000 m以上的青海湖盆地,向南于11 kaBP登上了4 000 m的青藏高原主体,向西在全新世早期进入柴达木盆地,并通过格尔木河河谷翻越昆仑山进入可可西里和羌塘高原。6～2 kaBP本区跨进新石器-青铜时代,有固定的聚落,发生了2次显著的文化扩散,5～4 kaBP马家窑文化在本区黄河-湟水谷地扩散;3 kaBP畜牧业的确立,人类再次向高原腹地扩散,并实现了对海拔4 000 m以上高原的长期占领。     

抗旱性晚稻品种筛选研究

选取湖南省当前生产上种植面积较大的8个水稻品种,采用盆栽土培搭配人工遮雨棚进行干旱胁迫试验,通过考察各品种在不同水分环境下分蘖盛期和孕穗期的叶片叶绿素相对含量、游离脯氨酸含量及各主要农艺性状,比较了各品种的抗旱性。结果表明湘丰优9号、岳优9113、岳优6135抗旱性较强,可以进一步进行大田试验,以确定其实际抗旱性能。