不同水稻品种对褐飞虱的耐虫特性研究

褐飞虱是中国水稻生产上最主要的害虫之一,以褐飞虱的耐虫性指数和抗生性指数以及F₁代种群繁殖率评价10个水稻品种耐虫特性。结果显示,在水稻三叶期接入8头褐飞虱低龄(1~2龄)若虫为害时,品种间的耐虫性差异明显,汕优63、秀水11、培矮64S/32E、Triveni、Utri Rajapan、嘉育948、ASD7等品种的耐虫指数大于抗生性指数,尤其是汕优63品种;而IR64、Rathu Heenati品种的耐虫指数明显小于抗生性指数。若用高龄(3~4龄)若虫为害,多数品种的耐虫指数上升。同一品种,成株期的耐虫指数高于苗期。试验进一步表明,当TN1、秀水11稻株枯死时,汕优63、培矮64S/E32、嘉育948、Triveni、Utri Rajapan中等受害,ASD7和IR64轻度受害,Rathu Heenati无受害症状。从褐飞虱F₁代数量来看,汕优63、培矮64S/E32与秀水11、TN1无显著差异,且均高于其他品种;嘉育948、Triveni、Utri Rajapan显著高于ASD7,后者又极显著高于IR64和Rathu Heenati。这些结果表明,汕优63、秀水11、TN1属感虫品种,无耐虫性和抗生性,培矮64S/E32、Triveni、Utri Rajapan属强耐虫性品种,IR64、Rathu Heenati属强抗生性品种,ASD7、嘉育948属耐虫性较强、抗生性较弱的品种。说明利用本文的评价方法基本上可以确定水稻品种的耐虫特性,这对耐虫品种的选育以及对褐飞虱可持续治理和保持品种抗性的稳定有着重要的现实意义。     

上甘山林场湿地松冻害调查研究

通过对江西省上高县上甘山林场的采脂湿地松林冻害状况的调查,分析了其灾害程度与立地条件、采脂状况的关系,为冻害后湿地松恢复技术提供科学依据。     

种子萌发期南瓜杂交品种耐盐评价

用浓度为120 mmol/L的Ca(NO3)2对22个南瓜杂交品种的耐盐性进行了研究。以与耐盐性有关的盐胁迫指数、主根长、侧根数、相对含水量和相对电导率为指标,运用隶属函数法综合评价其耐盐性,并进行聚类分析。结果表明,隶属函数法可以避免单一指标的片面性,能较为全面地评价南瓜的耐盐性。22个南瓜品种中,辉4×229-1独属一类,其耐盐性最强;045-3×云南4号、072-2×辉4、041-1×229-1、635-1×229-1、058-1×229-1和041-1×450同属一类,其耐盐性较强;007-2×长2、042-1×229-1和072-2×229-1同属一类,其耐盐性较弱。     

Weed control and sensitivity of oats (Avena sativa) with various doses of saflufenacil

Saflufenacil is a new herbicide being developed by BASF for broadleaved weed control in maize, soybean and other crops prior to crop emergence. Six field studies were conducted in Ontario, Canada over a three year period (2008-2010) to evaluate the potential of saflufenacil applied pre-emergence (PRE) at various doses for broadleaved weed control in oats. Saflufenacil applied PRE caused minimal visible injury at 1, 2 and 4 weeks after emergence (WAE) in oats. At 4 WAE, the dose of saflufenacil required to provide 95% control of Ambrosia artemisiifolia (common ragweed), Chenopodium album (common lambsquarters), Polygonum convolvulus (wild buckwheat), Polygonum scabrum (green smartweed) and Sinapsis arvensis (wild mustard) was 72 to >100, >100, 74, 58 and >100 g ai ha⁻¹, respectively. Generally, similar saflufenacil dose-response trends were seen at 8 WAE. The doses of saflufenacil required to provide 95% reduction in density and dry weight ranged from 95 to >100 and 42 to >100 g ai ha⁻¹ respectively for A. artemisiifolia, C. album, P. convolvulus, P. scabrum and S. arvensis. Oat yield showed no sensitivity to saflufenacil at the doses evaluated. Based on this study, saflufenacil applied PRE can be safely used in spring planted oats for the control of some troublesome annual broadleaved weeds.     

低温冻害对油菜产量的影响

分析了低温冻害对荆州油菜产量的影响,为今后的防冻救灾工作提出建议。     

耐低氮胁迫黄瓜品种的筛选

在正常供氮和低氮胁迫条件下,比较了18个黄瓜品种的产量、地上部生物量、植株氮素吸收总量及果实氮积累量的变化。结果表明：① 在低氮胁迫条件下,所有供试黄瓜品种的产量和果实氮积累量均有不同程度的下降,其中津优2号和津优31号下降幅度较小,津绿30号和美好下降幅度较大|津优2号和津优31号的地上部生物量、津优31号的植株氮素吸收总量有所升高,其余品种的地上部生物量、植株氮素吸收总量均有不同程度的下降,津绿30号和美好下降幅度较大|综合产量、地上部生物量、植株氮素吸收总量、果实氮积累量来看,津优2号和津优31号耐低氮能力较强,津绿30号和美好的耐低氮能力较弱。② 相关性分析表明,在低氮胁迫和正常供氮条件下,地上部生物量、植株氮素吸收总量和果实氮积累量均与产量呈极显著正相关,说明产量、地上部生物量、植株氮素吸收总量、果实氮积累量均可作为耐低氮胁迫的筛选指标。     

Performance of hybrids between transgenic oilseed rape (Brassica napus) and wild Brassica juncea: An evaluation of potential for transgene escape

Understanding the potential for the evolution of herbicide tolerance in weeds following gene flow from transgenic crops is important for their management. The inter-specific hybrids formed between four Brassica juncea populations with different glyphosate-susceptibility and transgenic oilseed rape was studied, emphasizing on the possible population difference. Compared with both parents, the fitness-related components and photosynthetic capacity of hybrids decreased dramatically, but significant differences were observed among different hybrids. All F₁ hybrids exhibited highly enhanced but similar herbicide tolerance level regardless of the wild B. juncea parent, indicating that genetically engineered herbicide tolerance may over-dominate phenotype ones by wild-crop hybridization. The analysis of parental loci transmission revealed a higher transfer ratio of male-specific loci detected in F₁ hybrids, suggesting that oilseed rape genetic markers can be transferred at relatively high frequencies to the next generation. Therefore, higher transfer ratio of oilseed rape-specific loci, coupled with variation of populations in fitness-related parameters in F₁ hybrids, could complicate environmental risk assessment of transgenic oilseed rape, especially in current agroecosystems with increasing application of glyphosate.     

丛枝菌根真菌提高黄瓜幼苗抗立枯病作用研究

为研究丛枝菌根真菌对黄瓜苗期立枯病的防治效果和相关生理生化变化。以黄瓜品种中农16为材料,播种时接种丛枝菌根真菌,对20 d幼苗人工接种立枯丝核菌。结果表明,接种菌根真菌后能够显著提高黄瓜苗期对立枯病的抗性,降低发病率。黄瓜苗期人工接种立枯丝核菌后菌根苗和非菌根苗发病率分别为16．5％和52．0％,非菌根苗发病严重,病情指数为46．7,接菌病情指数为10,较非接菌苗下降了78．5％,接种菌根真菌提高黄瓜抗病性与改变相关酶活性有关,在病害发生前菌根真菌已经与寄主植物互利共生,提前启动了抵抗病害得相关机制,如提高了保护酶活性,促进植株生长,接种菌根真菌后菌根苗地上鲜质量和地上干质量分别比未接菌处理提高33．10％和25.93％。在病害发生过程中菌根真菌与病原菌互相竞争,抑制病菌对寄主的侵害,减轻细胞膜受损害程度。     

20个高羊茅品种镉耐性评价及富集特征

采用水培试验,用10μM Cd~(2+)对20个高羊茅(Festuca arundinacea)品种进行处理,采用隶属函数值法和聚类分析法对其镉耐性和富集特征进行综合评价。结果表明,与对照相比,Cd~(2+)处理下所有参试高羊茅品种在株高、根长、生物量和光合色素含量等指标上均显著降低(P0.05),品种间变化值的差异也达到了显著水平(P0.05)。20份材料的平均隶属函数值变幅在为0.185~0.758,其中‘Commander’的镉耐性最强。20个品种间Cd~(2+)吸收和累积量也有很大差异,地上部Cd~(2+)浓度范围为106.66~150.97mg·kg~(-1),Cd~(2+)累积量最高值为6.87μg·株-1,最低值仅2.75μg·株-1,其中品种‘Commander’和‘Red Start’在Cd~(2+)吸收和累积上表现较好。通过综合评价最终将20个高羊茅品种分为4类,分别是高耐高吸收型:‘Arid 3’,‘Extreme’,‘Commander’,‘Escalade’,‘Ecological King’,‘Ky-32’,‘Red Start’,‘Green Label’;高耐低吸收型:‘Gold Crown’,‘Justice’,‘Honky Tonk’,‘Aries’;低耐高吸收型:‘RubyⅡ’,‘Coronado TDH’;低耐低吸收型:‘K31’,‘Crossfire Ⅲ’,‘Essential’,‘Super Watchdog’,‘Gram villa’,‘Dynamic Ⅱ’。     

黄瓜幼苗弱光耐受性相关指标研究

[目的]研究黄瓜幼苗弱光耐受性相关指标。[方法]以M22、M19-1、M14等18份弱光适应性不同的黄瓜品系为试材,利用光照培养箱控制光照强度,对照光强约为300μmol/(m2·s),弱光处理光强约为40μmol/(m2·s),研究黄瓜幼苗耐弱光指数、生长发育指标、光合特性及光合色素变化,并对黄瓜耐弱光相关指标进行相关分析。[结果]弱光处理后,黄瓜耐弱光品系如M22、M67的各指标变化不显著,弱光敏感品系M19-1的Chla/Chlb指标和不耐弱光品系M14的光合速率、蒸腾速率、叶面积及真叶鲜重指标明显低于对照。黄瓜幼苗的耐弱光指数与各性状的相关分析结果表明,除叶面积、真叶鲜重与耐弱光指数未达到显著相关外,其他均达到了显著相关或极显著相关。[结论]该研究可为黄瓜耐弱光品系选育提供理论依据。