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751.
模拟污水中氮,磷对水稻劝苗过氧化氢酶和乙醇酸氧化酶… 总被引:3,自引:0,他引:3
以水稻为材料,研究了不同深度的模拟污水中N、P对幼苗过氧化氢酶(Catalase,CAT,EC1.11.1.6)、乙醇酸氧化酶(Glycolateoxidase,GO,EC1.3.3.1)、过氧化和物酶(Peroxidase,POD,EC1.11.1.7)和叶绿素含量的影响。结果表明:低浓度N、P浓度分别超过8.56mmol.L^-1和0-0.2mmol.L^-1范围)可诱导CAT活性增大,而后下 相似文献
752.
水稻(品种:光辉)幼苗吸收k~+、NH_4~+、NO_3~-、H_2PO_4~-与这些离子在吸收液中的浓度关系是非常简单的。K~+、H_2PO_4~-、No_3~-的吸收与它在吸收液中的浓度具有显著的正相关。NH_4~+的吸收不受吸收液中的NH_4~+和其它离子的显著影响。从整体来看,离子吸收又是平衡的。 相似文献
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Inducible expression pattern of rice Bowman-Birk inhibitor gene<Emphasis Type="Italic">OsWIP1-2</Emphasis> and its protease inhibitory activity 总被引:3,自引:0,他引:3
CHENJun LIUJing GUOLei QULijia CHENZhangliang GUHongya 《科学通报(英文版)》2004,49(9):895-899
The WIP1-2 gene was cloned from rice. It be-longs to the Bowman-Birk inhibitor gene family. Northernblot showed that expression of this gene was induced bywounding and jasmonic acid (JA). It indicates that the OsWIPI gene plays an important role in the rice defense sys-tem. The OsWIP1-2 was cloned into pET28a and expressed inE. coli. Its expressed product was purified in the form offusion protein and tested for the inhibitory activities againsttrypsin and chymotrypsin. It was found that the fusion pro-tein could inhibit chymotrypsin, but not trypsin. It was alsofound that the His tag at its C-terminal affected its inhibitoryactivity significantly. The fusion protein with a naturalC-terminal had the inhibitory activity, while no inhibitoryactivity was detected in the fusion protein with a (His)6-tag atits C-terminal. This implies that extra amino acid residues atthe C-terminal of OsWIP1-2 may interfere with its correctfolding. The inhibitory assay indicated that the members ofrice Bowman-Birk inhibitor gene family probably differenti-ated both in their structure and function. 相似文献
757.
A CHASE domain containing protein kinase OsCRL4, represents a new AtCRE1-like gene family in rice 总被引:1,自引:0,他引:1
AtCRE1 is known to be a cytokinin receptor inArabidopsis. The AtCRE1 protein contains CHASE domain at the N-terminal part, followed by a transmitter (histidine kinase) domain and two receiver domains. The N-terminal CHASE domain of AtCRE1 contains putative recognition sites for cytokinin. Five CHASE domains containing proteins were found in rice, OsCRLla, OsCRLlb, OsCRL2, OsCRL3, and OsCRL4. OsCRL1a, OsCRL1b, OsCRL2 and OsCRL3 contain the four domains existing in CRE1, whereas OsCRL4 only contains the CHASE domain and a putative Ser/Thr protein kinase domain The authors cloned the encoding gene OsCRL4 and found that it represents a new member of the cytokinin receptor protein in rice. 相似文献
758.
ZHUYongsheng CHENBaotang YUShunwu ZHANGDuanpin ZHANGXueqin YANQiusheng 《科学通报(英文版)》2004,49(14):1481-1484
Asymmetric somatic hybrid plants were produced between cultivated rice (Oryza sativa L.) and wild species [O. meyeriana (Zoll. etMor, exSteud.)] with high resistance to rice bacterial blight. X-ray-irradiated protoplasts of the wild species were used as donor and chemically fused with iodoacetamide-inactivated protoplasts of rice cv. 02428 to produce hybrids. Seventy-two plants were regenerated from 623 calli based on metabolic complementation. The morphological characters of the plants closely resembled that of the rice. Simple sequence repeats were employed to identify their hybridity. Cytological analysis of root-tips revealed that their chromosome number varied in the range of 27--38. The somatic hybrids were inoculated with strains of Xanthamonas oryzae pv. oryzae at adult growth stage and demonstrated the resistance to bacterial blight introgression from the O. meyeriana. 相似文献
759.
水稻光温敏核不育系4112S和YW-2S的开花习性观察 总被引:3,自引:0,他引:3
通过对水稻光温敏核不育系4112S和YW-2S的开花习性的观察,发现这两个不育系具有开花集中,颖花开颖时间长,张颖角度大,柱头外露率高,柱头生命力不太长且下降快等特点.并就其高产稳产的制种技术措施进行了讨论. 相似文献
760.
发生规律:稻瘟病从水稻苗期到穗期都可发生。病菌在种子和稻草上越冬,带菌种子播种后,即可引起苗瘟。病菌随风雨传播到水稻的叶、穗、茎等部位后遇到适宜的温度即可萌发。此病菌在气温24℃~28℃,湿度大(相对湿度90%以上)时最易生长。因此,灌水过深,氮肥过多,会加重此病的危害。 相似文献