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161.
一个水稻落粒性基因SH1的SSR标记定位 总被引:2,自引:0,他引:2
以籼稻品种93-11为轮回亲本,与粳稻品种日本晴杂交并回交的高世代分离群体为研究材料,选用104个多态性的SSR标记对水稻的落粒性基因进行定位。结果表明,在BC4F2群体中,6个标记的基因型来自于日本晴;在BC4F3定位群体中,难落粒植株数与易落粒植株数的分离比例为3:1,落粒性受1对显性基因控制,命名为SH1;分子标记与落粒性共分离分析将SH1定位在SSR标记RM5389和RM1068、RM1387之间,与3个标记的遗传距离分别为0.7cM、5.5cM和13.1cM,此结果为该基因的分子标记辅助选择奠定了基础。 相似文献
162.
大豆豆荚光合特性及其对产量的贡献 总被引:3,自引:1,他引:2
以大豆东农42、东农163为试验材料,对不同生育期豆荚和叶片的光合速率、蒸腾速率、水分利用效率、气孔导度、叶绿素含量、可溶性蛋白含量等生理指标进行了研究,并通过在鼓粒始期R5、鼓粒期R6、生理成熟期R7对豆荚进行遮光处理,研究豆荚对籽粒重的影响。结果表明,豆荚具有光合作用的能力,光合速率在生理成熟期R7最高;蒸腾速率、气孔导度随着生育期的延续呈下降趋势,而水分利用效率逐渐上升;整个测定生育期内,东农42、东农163豆荚叶绿素含量分别占其叶片的7.63%和7.25%,可溶性蛋白含量占其叶片的53.47%和48.82%;在鼓粒始期R5进行遮光处理表明,豆荚的光合产物对籽粒重的贡献率达到7.34%~15.06%。 相似文献
163.
As a major agricultural province responsible for national food security,at present it has become the largest province in the cultivation and sales of the pod pepper.All producing area of pod pepper in Henan has formed different interplanting system with main crop according to geographical climate characteristics.This paper summarized the interplanting systems of pod pepper in different area of Henan province for reference. 相似文献
164.
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166.
Expression of the double‐stranded RNA of the soybean pod borer Leguminivora glycinivorella (Lepidoptera: Tortricidae) ribosomal protein P0 gene enhances the resistance of transgenic soybean plants
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Fanli Meng Yang Li Zhenyuan Zang Na Li Ruixue Ran Yingxue Cao Tianyu Li Quan Zhou Wenbin Li 《Pest management science》2017,73(12):2447-2455
167.
B.A. Zurweller A. Xavier B.L. Tillman J.R. Mahan P.R. Payton N. Puppala 《Journal of Crop Improvement》2018,32(4):532-551
Genetic gains of cultivated peanut (Arachis hypogaea L.) have increased harvest index and disease tolerance, resulting in improved yield potential and broad-range adaptability of peanut cultivars to United States (U.S.) peanut production regions. Although this strategy has been successful, future yield increases may require peanut cultivars specifically adapted to environmental and management systems of a particular production region. Irrigation is one major management factor that varies across U.S. production regions and influences yield stability. Therefore, peanut germplasm selection for developing specifically adapted cultivars depends on knowledge of genotypic (G) pod yield responses to irrigation (M) across contrasting environmental (E) conditions (G × E × M interaction). The objectives of this 2-year study were to characterize germplasm by: (i) examining genotypic pod yield response to irrigation at locations in Florida and Texas; and (ii) estimating the genotypic pod yield performance and stability using genotype plus genotype-by-environment interaction (GGE) biplots. At the Florida location, genotypes New Mexico Valencia C (NMVC), COC 041, and Chico responded positively to increasing water application, whereas FloRun? ‘107?, C76 16, and FlavorRunner 458 responded negatively. Genotypes C76 16, ICGS 76, Chico, and ICGV 86015 had pod yields greater than the population mean. The genotype ICGS 76 had both high pod yields and stability. Pod yields of Chico were greater at the southwest locations, whereas ICGV 86015 had greater pod yields at the southeast locations. These results demonstrate a range in adaptability of distinct peanut genotypes that can be used in breeding programs for developing improved cultivars.Abbreviations: G × E: genotype-by-environment interaction; G × E × M: genotype-by-environment-by-management interaction; G × M: genotype-by-management interaction; NMVC: New Mexico Valencia C; TWRPET: total water received as a percentage of ETo 相似文献
168.
A. L. Singh A. Zala H. Bariya S. Kumar Y. S. Ramakrishna 《Journal of plant nutrition》2017,40(19):2756-2767
Boron (B) deficiency is a common factor in light-textured soils causing poor pod filling and yield in large seeded peanut. Field trials were conducted in soils having 0.20–0.45 mg kg?1 available B to find out the effectiveness of commercial-grade B sources in large seeded peanuts. B application induced early flowering, increased pods, yield and yield attributes, shelling and 100-seed weight. Soil application of 2.0 kg B ha?1 as commercial-grade Agricol, Solubor and Borosol increased these parameters to a similar degree as obtained by borax, but were superior over their foliar applications. Similarly, the responses of foliar applications of 1.0 kg B ha?1 as Chemiebor, Solubor and Borosol were more effective in humid areas. However, foliar applications led to scorching of peanut leaves during dry weather. Thus, soil application of 2.0 kg B ha?1 is essential to enhance productivity and pod filling in large seeded peanut. 相似文献
169.
为了阐明免耕和常规翻耕20 cm下花生不同器官铁累积利用差异,在鲁东花生主产区3个典型棕壤试验点(望城、夏甸和齐山)系统研究了免耕和常规翻耕下花生铁营养特性变化。结果表明,相比免耕处理,常规翻耕20 cm增加了花生籽仁铁的累积,在望城点、夏甸点和齐山点分别增加了38.4%、20.2%和51.2%,且籽仁铁的累积与籽仁氮的累积及花生产量呈极显著正相关(P0.01)。免耕处理促进了花生茎、叶、果针和果壳等器官中铁的奢侈累积,在望城点、夏甸点和齐山点,这4个器官铁的累积量比常规翻耕处理分别提高了6.0%、32.1%和14.7%,同时花生累积带走的总铁量高于常规翻耕处理,从而造成土壤有效铁含量及土壤铁活化系数均比常规翻耕处理下降了15.1%~32.9%。综上,土壤翻耕措施能够有效增加花生籽仁铁的累积分配,降低茎、叶、果针和果壳等器官中铁的无效累积,从而提高花生铁的利用效率,该研究结果为花生田铁营养合理管理提供了理论依据。 相似文献
170.
Lúcia Cristina VriesmannRenata Dias de Mello Castanho Amboni Carmen Lúcia de Oliveira Petkowicz 《Industrial Crops and Products》2011,34(1):1173-1181
The composition of cacao pod husks (CPHs), the main waste product of cocoa production, and some of the characteristics of their water-soluble pectins were investigated. Milled and dried CPHs were submitted to hot aqueous extractions (50 and 100 ?C, 90 min, 1:25, w/v). The obtained fractions (labeled 50W and BW, respectively) yielded 7.5 and 12.6% pectins, respectively. The monosaccharide composition revealed the predominance of uronic acid, followed by galactose, rhamnose and arabinose, characteristic of pectins. Chemical and spectroscopic analyses (FT-IR and 13C NMR) showed that both fractions contained high acetyl contents (DA 29.0 and 19.2%, respectively) and are composed of low methoxyl homogalacturonans (DE 37.0 and 42.3%, respectively) with rhamnogalacturonan insertions carrying side chains containing mainly galactose. Rheological analyses were carried out with 50W and BW. Solutions of both fractions at 5% (w/v) had a non-Newtonian shear-thinning behavior, however that of 50W showed higher apparent viscosity than that of BW. Dynamic oscillatory analyses showed that 5% (w/w) 50W pectin had weak gel behavior whereas at the same concentration, BW pectin behaved as a concentrated solution. Although further investigations are required, CPH seems be a potential source of both pectins and other natural agents such as fibers and phenolics, and its use is particularly justified by growing environmental awareness. 相似文献