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王新望  王惠萍 《作物学报》1995,21(2):215-222
对不同熟性棉花品种功能叶几种酶活性及脂质过氧化水平(以丙二醛含量表示)的研究结果表明,超氧物歧化酶(SOD)活性在吐絮前呈波动上升,吐絮盛期争剧下降;丙二醛(MDA)含量吐絮前缓慢上升,吐絮后明显增加;过氧化氢酶(CAT)活性在结铃以前随叶片发育而上升,结铃后急剧下降;过氧化物酶(POD)活性始终呈上升趋势。进一步对POD同工酶进行电泳发现,其酶谱构成随生育进程而变化,早熟品种在开花期酶带条数最多  相似文献   
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对在山东的济南、平度、莱西、烟台种植的几种陆地棉(Gossypium hirsutumL.)核雄性不育材料的育性表现进行了研究,结果表明:洞A不育系的衍生材料MB、MA在不同气候条件下有育性的变化。在济南高度不育,可作为不育系。在其他几个地区表现不同程度的可育。其中MB在平度有相当好的育性,能正常结铃。而双隐性核不育材料59A、62A未能观察到育性变化。本文就核不育材料在棉花杂交制种中的应用前景及需深入研究的问题作了探讨。  相似文献   
4.
A phytotoxic protein that evokes the typical symptoms of Verticillium wilt disease in seedlings of Gossypium hirsutum L. (Upland cotton) was isolated from culture filtrates of Verticillium dahliae. The protein was purified by ammonium sulfate precipitation, Sephadex-G100 fractionation, and native PAGE. The 18.5 kDa protein, designated VD18.5, appears to be a single subunit protein with an isoelectric point between 3 and 5. VD18.5 induces symptoms of leaf dehydration, chlorosis, necrosis and stem discoloration in seedlings of the disease susceptible cotton cultivar Siokra 1–4. The LD50 of VD18.5 on protoplasts of Siokra 1–4 was 18 μg mL−1. VD18.5 had no noticeable effect on Pima S-7, which is a disease resistant cultivar. Phytotoxic activity was partially destroyed at high temperature and was abolished by digestion with proteinase K. Mass spectrometry fingerprinting and protein sequence data from VD18.5 yielded no significant matches when submitted to the Mascot search engine and NCBI non-redundant protein databases, respectively. These results suggest that VD18.5 is a novel protein that may be involved in the development of some of the symptoms associated with Verticillium wilt disease in the cotton plant.  相似文献   
5.
Cross sections of woody stems of 309 diseased grapevines collected in France showed two kinds of necrosis typical of esca: a) A central light-colored necrosis of soft consistency, consisting of three zones, preceded by a centrally discolored wood, and b) a sectorial light-colored necrosis composed of two zones preceded by a sectorial brown necrosis. Isolations showed that different microflora was associated with each necrosis. Phaeoacremonium aleophilum and Phaeoacremonium chlamydosporum occurred in the discolored wood and the zones bordering the central decayed wood. Eutypa lata was the main fungus isolated from sectorial brown necrosis and the zones adjoining the decay wood. Phellinus punctatus was isolated from the sectorial and central decayed wood. Stereum hirsutum was present in decayed wood of 15 grapevines with esca symptoms not inhabited by P. punctatus. Wood decay tests and pathogenicity tests showed that S. hirsutum and P. punctatus were responsible for the decayed wood. Phaeoacremonium chlamydosporum and S. hirsutum produced a centrally discolored wood similar to that found in esca-affected vines. Phaeoacremonium aleophilum caused a sectorial brown necrosis of soft texture. From these studies, it was found that esca is a complex disease involving several microorganisms whose role in the process leading to wood degradation is discussed.  相似文献   
6.
2011年10月-2014年10月连续3年在河北省任县安排了定位试验,通过饲用黑麦不同播期与棉花构建几种棉草复种茬口搭配方式,从产量、经济效益、水分利用效率和养分利用效率以及对土壤肥力影响等方面综合分析棉花饲用黑麦复种的可行性及复种方式。结果表明,棉花可与饲用黑麦复种,为降低饲用黑麦对棉花的影响,饲用黑麦可适当推迟到10月20日播种,次年4月底收获,效益可提高5470.1元·hm-2。棉花饲用黑麦复种与棉花单作相比,平均水分利用率提高16.49%;水分经济利用效率提高56.54%;并且土壤有机质平均增长幅度提高5.71%,土壤含盐量平均降低幅度达到23.72%,土壤改良效果明显;是适用于该区域的高效复种模式。  相似文献   
7.
[Objective] The aim of this study was to obtain the flanking sequences of T-DNA in the transgenic cotton containing a GbVe1 over-expression cassette. [Method] The T-DNA insertion copy number in the transgenic GbVe1 cotton was analyzed by southern blot. Flanking sequences of the transgenic lines with putative single T-DNA insertion copy were obtained using high-efficiency Thermal asymmetric interlaced polymerase chain reaction (hiTAIL-PCR). The T-DNA insertion sites were further confirmed by PCR with specific primers. [Result] RB-flanking sequences (119-1 018 bp) and LB-flanking sequences (243-516 bp) were obtained from three transgenic lines with low copy number of T-DNA insertion. The AT content was more than 63% in these flanking sequences. A same single insertion site in the intron of Gohir.D01G157600.1 was found in the two transgenic lines 7/100826-152 and 12/100826-393, while two separated insertion sites, one also in the intron of Gohir.-D01G157600.1 and the other in the intergenic region of A12 chromosome, were found in the transgenic line 1/w-ch14. A deletion of 21 bp was found in the insertion site in the intron of Gohir.D01G157600.1. The T-DNA insertion in the intron of Gohir.D01G157600.1 was further confirmed by the specific PCR. [Conclusion] The flanking sequences of T-DNA in the transgenic GbVe1 cotton were obtained and the specific transformation event in the intron of Gohir.D01G157600.1 was further confirmed by PCR.  相似文献   
8.
为了解IAA与棉纤维品质形成间的关系及棉铃各部位IAA积累转运特点,本研究分析了棉铃各部分在发育过程中IAA含量的变化特点。通过选择陆地棉标准系TM-1、长纤维种质‘母35’和短纤维种质‘208’3个纤维长度差异较大的陆地棉材料,利用酶联免疫法对浙江杭州、海南三亚两地田间试验的各材料不同发育阶段的棉仁、棉籽壳、棉纤维、棉铃壳进行了IAA含量的测定。结果表明,不同参试材料的棉仁IAA含量存在明显差异,棉籽壳、棉纤维与棉铃壳的IAA含量峰值出现时间晚于棉仁,棉铃各个组织IAA含量具有随棉铃组织从内向外逐渐降低的趋势。研究表明,IAA可能是棉纤维发育的正效应因子,且棉铃发育过程中IAA可能呈初期在棉仁富集、随发育进程沿棉铃组织由内向外运输的规律。  相似文献   
9.
ABSTRACT

The objective of this study was to examine the effect of late planting on sucrose metabolism in cotton bolls and the relationship to fiber properties and within-boll yield components. Two cotton lines A201 and A705 were employed in a sowing date experiment where two temperature regimes during boll maturation period were created at mean daily temperature of 26.8°C, 28.3°C for early planting and 25.2°C, 23.1°C for late planting in 2016 and 2017, respectively. Boll size, seed mass per boll, seed index and fiber length were increased, and lint percentage was decreased by late planting. Greater cell wall invertase activity and the resultant hexose concentration in fibers were observed in late planting, and thus led to decreased osmotic potential accounting for the enhanced fiber length. Similarly, late planting increased the maximum of vacuolar invertase activity in ovules occurring at 5 days post anthesis (DPA) and hexose concentrations in embryos from 10 DPA afterwards which may favor embryo cell division, and thus increase final seed size. Our data indicate that acid invertase and hexose are implicated in the formation of within-boll yield components and fiber properties as affected by the lower temperature regime due to late planting.  相似文献   
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