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21.
发表了东北产光砂蒿的两个新变种,即疏花光砂蒿(Artemisia oxycephala Kitag. var. sporadantha W. Wang)和金砂蒿(A. oxycephala Kitag. var. aureinitens W. Wang) 相似文献
22.
褐飞虱侵害后不同水稻品种根及叶片脱落酸含量的变化 总被引:2,自引:0,他引:2
为了解褐飞虱Nilaparvata lugens (Stål)侵害后水稻耐虫性与植物体内源激素关系,应用酶联免疫吸附法(enzyme-linked immunosorbent assay, ELISA)研究褐飞虱若虫侵害分蘖期超级培矮64S/E32和TN1,灌浆期协优963和TN1后根及叶片脱落酸(abscisic acid, ABA)含量变化.结果表明:褐飞虱侵害分蘖期超级培矮64S/E32和TN1后3 d,叶片ABA含量显著上升,ABA含量根冠比(根ABA/叶片ABA)显著下降;侵害后6 d,超级培矮64S/E32叶片ABA含量显著下降,根冠比显著上升;但TN1叶片ABA含量在褐飞虱侵害后3 d和6 d显著上升,根冠比显著下降.褐飞虱侵害灌浆期协优963与分蘖期超级培矮64S/E32变化一致,TN1在褐飞虱侵害后3 d叶片ABA含量显著上升,根冠比显著下降;侵害后6 d,叶片ABA含量、ABA含量根冠比均显著上升.由ABA含量变化百分比可见,分蘖期ABA含量变化幅度较灌浆期大;耐虫品种变化幅度较感虫品种大,持续期较感虫品种短;叶片变化幅度较根部大.褐飞虱侵害后,两种不同生育期两种抗性不同的水稻品种比较,耐虫品种叶片ABA含量先上升(3 d)后下降(6 d),ABA含量根冠比先下降(3 d)后上升(6 d);感虫品种叶片ABA含量持续上升(3 d和6 d),分蘖期ABA含量根冠比持续下降(3 d和6 d),灌浆期ABA含量根冠比先下降(3 d)后上升(6 d);耐、感虫水稻品种根部变化规律不明显.这些差别表明不同水稻(耐虫和感虫)品种受褐飞虱侵害后体内ABA含量变化规律不同.本研究结果对深入阐明水稻耐虫品种的机制具有重要参考价值. 相似文献
23.
在人工气候室内比较研究了灰飞虱和褐飞虱在汕优63和秀水11上的种内和种间密度效应对其主要生物学参数的影响,结果表明两种稻飞虱均存在显著的种内竞争,主要表现为随着密度增加,若虫发育历期延长、若虫羽化率下降、雌成虫寿命缩短、每雌产卵量下降。种内密度效应与稻飞虱种类和寄主品种有显著互作关系,灰飞虱种内竞争较褐飞虱明显,二者在适宜寄主上种内竞争更为明显。同时,两种稻飞虱存在着显著的种间密度效应,主要表现为异种存在时的促进作用,即异种共存时若虫历期缩短、若虫羽化率提高、雌虫寿命延长、每雌产卵量增加。种间密度效应也与稻飞虱种类和寄主品种有显著互作关系,两种共存对灰飞虱的有利作用显著大于对褐飞虱的有利作用,在欠适宜寄主上种间互利效应更为明显。最后,本文对稻飞虱种内和种间密度效应的机制和进化意义进行了讨论。 相似文献
24.
《Expert review of proteomics》2013,10(3):321-331
Wine proteins play an important role in the quality of wine, because they affect taste, clarity and stability of product. The majority of wine proteins are in the range of 20–30 kDa. Different mass spectrometry (MS) techniques have been successfully applied to study the grape and wine proteins. By liquid chromatography (LC) electrospray ionization (ESI) MS and nano-LC/MS, nine dipeptides and 80 peptides were unambiguously identified in Champagne and Sauvignon Blanc wines, respectively. Using matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) and surface-enhanced laser desorption/ionization TOF, the protein and peptide fingerprints in Chardonnay, Sauvignon Blanc and Muscat of Alexandria wines were determined. MALDI-TOF identified the mesocarp proteome of six Vitis grape varieties. Proteins in different grape tissue extracts were also studied. The major grape pathogenic-related proteins are chitinases and thaumatin-like proteins, which both persist through the vinification process and cause hazes and sediments in bottled wines. ESI-MS, LC/ESI-MS and MALDI-TOF analysis of these proteins in grape and wine were also used to characterize different grape varieties. 相似文献
25.
周永力 《植物遗传资源学报》2013,14(3):390-394
采用菲律宾10个代表菌株和我国V型菌代表菌株在植株的分蘖初期和孕穗期人工接种,鉴定和评价近年选育的26个“绿色超级稻”品种(系)对白叶枯病的抗性。结果表明多数品种在分蘖初期和孕穗期对病菌的抗感水平相同,少数品种接种在孕穗期接种部分菌株后的病斑长度小于苗期。此外,新黄占、华201S-1 和XF10450在分蘖初期和孕穗期接种10个菌株后的病斑长度均小于5cm,具有高度的广谱抗性;其它品种对不同菌株的抗性水平不同,黄华占、旱优113、新两优3411和天优145对4-5个菌株表现抗病,旱优75、旱优715和009067对测试的10-11个菌株高度感病;其它品系对所有菌株表现中度感病或感病。
关键词:水稻品种;白叶枯病;抗性 相似文献
26.
Twelve varieties of improved and local (landrace) sorghum were tested under artificial inoculation conditions. Out of 12 sorghum varieties evaluated with covered kernel smut, notably local cultivar ‘Tetron’ was found to be highly resistant. Disease incidence and severity on the rest of the cultivars varied from 21 to 47% and 40 to 53% respectively. Differences among cultivars in yield loss were also observed. The highest yield loss (40%) was recorded on 97 MW 6129 (NVT-11 4) and for Tetron yield loss was nil. The effect of disease on germination was noticed but cannot be considered as conclusive due to moisture stress at the time of germination. 相似文献
27.
Olfactory cues explain differential attraction of the striped rice stem borer to different varieties of rice plant
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In Iranian rice fields, different varieties of rice are cultivated which are differentially impacted by females of the rice stem borer, Chilo suppressalis. To elucidate the role odours may play in their host plant finding behaviour, female Ch. suppressalis were exposed to four varieties of rice plants and their volatiles in a four‐arm olfactometer. In whole plant tests, Ch. suppressalis were significantly attracted to the variety previously characterized as most susceptible, least attracted to one characterized as semisusceptible, and showed no attraction to those varieties characterized as semi‐ and highly resistant. Tests using headspace volatile extracts yielded similar results in the case of the most susceptible variety, but showed no attraction to the semisusceptible and highly resistant varieties, and low attraction to the semiresistant variety. Subsequent analysis of the volatile composition identified a panel of 27 components, some of which were either unique to, or abundantly present in, particular varieties, and may explain the observed variation in their attractiveness. Our findings show that rice plant volatiles can play a role in the host selection behaviour of this pest species, and we suggest compounds which may be important to this process and the future application of volatiles in rice pest management programs. 相似文献
28.
地黄SCoT分子标记体系的建立和指纹图谱的构建 总被引:1,自引:0,他引:1
该研究采用L_(25)(5~6)正交设计和单因素两种方法,对影响地黄SCoT-PCR反应的5个因素(模板DNA浓度,引物浓度,ddH_2O和Mix的用量以及退火温度)进行了优化。结果表明:优化后的反应体系总体积为25μL,含有8μL ddH_2O,1μL模板DNA(80 ng·μL~(-1)),1μL引物(8μmol·L~(-1))和15μL Mix,退火温度为45℃。运用30份地黄种质材料,对优化的SCoT-PCR正交体系进行多次重复验证,获得了多态性丰富、条带清晰的扩增图谱,证明该反应体系稳定可靠。利用该体系对32条SCoT引物进行两次筛选,得到14个扩增产物清晰、重复性好且多态性条带相对较高的引物。利用SCoT_4等5条引物构建了上述地黄2个种共30份种质的SCoT指纹图谱。利用这5个SCoT引物指纹图谱可将7个地黄常用栽培品种区分开。这表明SCoT分子标记体系适用于地黄主要品种亲缘关系及遗传多样性的研究,所构建的指纹图谱也为地黄常见的7个栽培品种的区分提供参考依据。 相似文献
29.
30.
TIE-GUANG XIA JIANG-XIA TANG 《Insect Science》2007,14(4):317-321
The effects of four rice varieties highly susceptible ( Xiang-Zao-Xian31 and Jia-Yu 164 ), moderately susceptible ( Wei-You402 ), and resistant ( Zhu-Liang-You02 ) to the whitebacked planthopper Sogatellafurcifera on the nymphal development, reproduc- tion and survival of Microvelia horoathi were investigated through a food chain using SogateUafurcifera as herbivore prey. Significant longer nymphal developmental time were observed in the 1 st, 4th, 5th instar and whole nymphal stage of M. horvathi raised on S. furcifera fed ZLY02 and WY402 than those of the other two varieties. M. horvathi raised on S. furcifera fed resistant ZLY02 showed a significant lower survival of whole nymphal stage than those fed other three susceptible varieties. Moreover, M. horvathi raised on S. furcifera fed resistant ZLY02 had shorter female longevity and lower lifetime fecundity than those of on susceptible XZX3l. Our results suggest that the S. furcifera- resistant rice variety ZLY02 had a negative effect on the growth and development of the predator M. horvathi through a food chain. 相似文献