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71.
Little information exists concerning how crops will respond to the predicted increased night temperatures. The objective of this work was to determine if respiration and growth of sorghum [Sorghum bicolor (L.) Moench], a C, plant, and sunflower (Helianthus annuus L.), a C3 plant, are affected when the night temperature is increased by 5°C compared to the long-term (19 year) average night temperature in June in Kansas. Sorghum and sunflower were grown in two walk-in growth chambers with either the ambient night temperature (21C) or a high night temperature (26C). Day temperature was the same for all plants (27C). Both sunflower and sorghum had higher respiration rates under the elevated night temperature than under the ambient temperature. The average respiration rate of sunflower grown under elevated night temperature increased by 19% (0.89 vs. 0.75 μmol m?2 s?1) and that of sorghum by 44 % (0.52 vs. 0.36μmol m?2s?1). After 74 days, sunflower plants grown under the ambient night temperature were 30.2 cm taller than sunflower plants grown under the elevated night temperature; sorghum plants under the ambient temperature were 24.8 cm taller. Sunflower plants grown under the elevated night temperature formed flowers one week earlier than those grown under the ambient temperature. Sorghum formed no flowers by 74 days. Results suggest that, if climate change does increase night temperature, respiration will be increased more in C4, than C3 plants. 相似文献
72.
食(药)用菌与有益微生物相互作用效应研究进展 总被引:3,自引:0,他引:3
本文综述了有关食用、药用菌与其它有益微生物相互作用及效应研究方面的现状及新进展,讨论了有益微生物对食用、药用菌栽培的影响;相互作用的机制;在食用、药用菌栽培中充分利用有益微生物的前景 相似文献
73.
74.
从多糖丰富的样品中制备食用真菌DNA 总被引:21,自引:0,他引:21
本文报道了一种从多糖丰富的食用真菌样品中快速、简便制备高分子量总DNA的改进方法。通过CTAB在不同的氯化钠浓度下选择沉淀DNA,除去多糖污染,苯酚、氯仿抽提,异丙醇沉淀,就可获得适宜多种分子生物学研究的食用菌基因纽DNA。本方法也适合小规模同时制备多个样品。另外,采用本方法制备的真菌DNA,经限制酶HaeⅢ酶切后在琼脂糖凝胶上能显示出菌株特异性的DNA带谱,可用于食用菌的遗传育种、菌株鉴定等研究。 相似文献
75.
日光温室间作新模式对环境因子及菇菜生长的影响 总被引:4,自引:0,他引:4
采用反遮光内拱棚模式,在日光温室内进行菇菜间作,研究对环境因子及菇菜生长的影响。结果表明:反遮光内拱棚日均温度15.5℃,最高22℃,最低12℃;相对湿度平均96.7%,最高99%,最低90%;光照强度最高为0.5klx;CO2平均浓度为828μL·L-1,最高为1000μL·L-1,最低为630μL·L-1,完全满足金针菇生长需求。通过斜拉秧措施,极大提高了黄瓜窄行光照强度,提高了保护地栽培效益。 相似文献
76.
CAS‐12 is a sunflower mutant with increased levels of palmitic (C16: 0 = 30%) and oleic (C18: 1 = 55%) acids in its seed oil, hence it has a reduced linoleic acid content (C18: 2 < 5%). This study was conducted to determine the inheritance of high C16: 0 content and its relationship with high C18: 1 content in CAS‐12. Reciprocal crosses involving CAS‐12, CAS‐5 (high C16: 0 content), HAOL‐9 (high C18: 1 content) and HA‐89 (standard fatty acid profile) were made. The F1, F2 and BC1F1 generations were obtained. The genetic control of the high C16: 0 trait in CAS‐12 was partially recessive and gametophytic. In all cases, this character segregated in the ratio 19: 38: 7 (low: intermediate: high C16: 0 content) in the F2 generation. These results, together with the lack of segregation for C16: 0 content in crosses between CAS‐12 and CAS‐5, indicated that the genetic control of the high C16: 0 trait in CAS‐12 was similar to that in CAS‐5 in being controlled by partially recessive alleles (p1, p2, and p3) at three loci. Crosses between HA‐89 and CAS‐12, and HAOL‐9 and CAS‐5 (segregating for C16: 0 and C18: 1) demonstrated that the high C16: 0 and the high C18: 1 traits were independently inherited. However, C18: 1 segregation in these crosses exhibited reversal of dominance. Apparently, the low C18: 1 parental lines carried modifier genes causing the deviation. 相似文献
77.
Accumulation of soluble phenolic compounds in sunflower capitula correlates with resistance to Sclerotinia sclerotiorum 总被引:2,自引:0,他引:2
Disease symptoms and total soluble phenolics content have been analysed in four sunflower (Helianthus annuus L.)lines with different resistance levels(from highly susceptible to resistant) to head rot caused by Sclerotinia sclerotiorum (Lib.) de Bary. At the beginning of the flowering stage, capitula were inoculated by spraying with a water suspension of
ascospores, and disease symptoms were evaluated from day 6 to day14 after inoculation. The most susceptible genotypes showed
all their ovaries to be necrosed and abundant lesions in corollas, bracts and receptacle. In the resistant line, the ovary
and corolla were only partially necrosed with no symptoms in the bracts or the receptacle. Total soluble phenolics were extracted
and quantified from different parts of the capitulum in both inoculated and non-inoculated plants. The amount of phenolic
compounds depended on the sunflower line, the time after inoculation, and the tissue. Higher constitutive and induced phenolic
content as well as phenylalanine ammonia-lyase activity were present in the most resistant line, these differences correlated
with the absence/presence of disease symptoms.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
78.
79.
Three diploid perennial sunflower species are useful for variety improvement: Helianthus mollis, because of sessile leaves, H. salicifolius, because of a high oil concentration, and H. maximiliani, a potential source of resistance to Sclerotinia sclerotiorum. The crossability of these species to cultivated sunflower was examined.Hybrids were obtained from eight combinations, with 3–15 F1 plants per combination. The F1's exhibited the dominant phenotype of the wild species. Pollen viability varied between 32.1 and 69.9%. Meiosis was irregular in the F1 hybrids. At diakinesis, bivalents (62.7–97.9% of meiocytes), univalents (0–31.23%), and multivalents (3.84–7.68%) were detected. At anaphase I, chromosome bridges were detected in 6.77 to 11.44% of meiocytes. Fast chromosomes in metaphase I, and lagging chromosomes in anaphase I and telophase II were evidenced in a high percentage of meiocytes. 相似文献
80.
Construction and characterization of a BAC library for sunflower (Helianthus annuus L.) 总被引:1,自引:0,他引:1
A bacterial artificial chromosome (BAC) library was constructed using the sunflower (Helianthus annuus L.) restorer line RHA325, which carries the restorer gene Rf1 and the Pl2-gene conferring resistance to downy mildew. High molecular weight DNA was prepared from nuclei using leaf material from two-week old seedlings. The library was constructed using the HindIII site of pBeloBAC11. The current BAC library comprises 104,736 clones. The insert size of the clones varied between 20 and 270 kb, with an average insert size of 60 kb. The whole 1.9× sunflower BAC library was spotted in duplicate on four high-density filters, each carrying 55,296 clones. The content of organellar DNA, which was estimated by colony hybridisation against the mitochondrial probe coxI and the chloroplast probe rbcL, proved to be less than 0.03 and 0.1%, respectively. BAC pools, allowing PCR-based screening, were made and used to identify positive BAC clones for the markers OP-K13_454, closely linked to the restorer gene Rf1. The PCR-based screening was verified by the results obtained for this marker by colony hybridisation. 相似文献