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141.
土壤含水量对美国黑莓光合特性的影响 总被引:4,自引:1,他引:4
为探索不同土壤含水量对黑莓光合特性的影响,以盆栽美国黑莓2~3年生扦插植株为试材,在6种土壤相对含水量(SRWC)条件下,对其光合特性进行研究。结果表明,土壤相对含水量为100%时,叶片净光合速率日变化呈单峰曲线;随着土壤含水量的降低,其净光合速率日变化呈双峰曲线。美国黑莓的光补偿点为50μmol/m2·s左右;SRWC为25%时,其光饱和点仅为330μmol/m2·s;SRWC为70%以上时,光饱和点均为1280μmol/m2·s左右。叶片的净光合速率及蒸腾速率随SRWC的升高而增加,气孔阻力随SRWC的升高而降低。水分利用率随着SRWC的降低而提高,呈极显著的负相关;新梢生长对土壤水分极为敏感。净光合速率与蒸腾速率呈显著正相关,与气孔阻力呈极显著负相关;蒸腾速率与气孔阻力呈显著负相关。美国黑莓的光合作用最适SRWC为85%;灌溉的临界SRWC为40%。 相似文献
142.
Since the arrival of Drosophila suzukii M. (Diptera: Drosophilidae), field applications of broad-spectrum insecticides have increased in berry crop production to protect susceptible fruits from infestation. Field studies were conducted from 2011 to 2013 to determine whether alternate row middle or border spray programs could manage D. suzukii as well as complete sprays and have less of an impact on non-target arthropods. Four raspberry sites and one blueberry site were alternate row middle and border sprayed, respectively. Adult and larva counts of D. suzukii were compared to conventional complete spray programs. Non-target arthropods were evaluated 7 d post-harvest. In both reduced spray trials, no differences in mean adult numbers and larvae of D. suzukii were detected between treatments. Mean counts immediately after sprays (i.e. 3–12 d after treatment) were also similar in complete and alternate row sprays. Both reduced spray strategies had significantly more Stethorus spp.; additionally, alternate row sprays had significantly more Psyllobora spp. These reduced pesticide strategies are additional tools to consider in D. suzukii IPM programs that can reduce the area sprayed, application time, and input costs while conserving natural enemies. 相似文献
143.
144.
以小浆果树莓果实为原料,采用咔唑比色的方法,利用超声波法研究了超声波提取时间、超声功率和料液比对果胶提取量的影响,在此基础上进行L9(33)正交试验,确定了超声波法提取树莓果实中果胶的最佳提取条件为:料液比为1∶80,超声功率为400 W,超声波提取时间35 min,果胶含量可达1.21%。 相似文献
145.
以盆栽3年生美国黑莓(Rubussubgenusrubuswatson)植株为试材,对25%、40%、55%、70%、85%、100%6种水分胁迫条件下的光合特性进行研究。结果表明:土壤相对含水量(SRWC)为100%时,叶片的光合速率日变化呈单峰曲线;随着水分胁迫的加剧,其光合速率日变化呈双峰曲线。美国黑莓的光补偿点为50μmol/(m2.s)左右;当SRWC为25%时,其光饱和点仅为330μmol/(m2.s);当SRWC为70%以上时,光饱和点均为1 280μmol/(m2.s)左右,属喜光树种。叶片的光合速率及蒸腾速率随SRWC的升高而增加,气孔阻力随SRWC的升高而降低。光合速率与蒸腾速率呈正相关、与气孔阻力呈极显著负相关;蒸腾速率与气孔阻力呈负相关;水分利用率随着水分胁迫的增强而提高;美国黑莓的光合作用适宜SRWC为70%以上;灌溉的临界SRWC为40%。 相似文献
146.
147.
Summary Red raspberry varieties known to be susceptible to raspberry bushy dwarf virus (RBDV) are listed. Experiments at East Malling suggest that some varieties previously thought to be immune to RBDV are not so although they are difficult to inoculate by grafting. Additional varieties tested may possibly be immune. The response of varieties derived from Lloyd George and segregation in progenies derived from resistant varieties suggest that the genetic control of susceptibility may be by dominant complementary genes. 相似文献
148.
Summary Strong resistance to the cane diseases Elsinoë veneta, Didymella applanata and Botrytis cinerea, and to Sphaerotheca macularis, occurred in F1 and BC1 derivatives of an accession of Rubus coreanus. Resistance to cane spot (E. veneta) was polygenic.In eight out of ten BC1 progenies, average grades for cane spot infections were significantly higher in white-flowered (an
1) than pink-flowered (An
1) plants and in hairy-caned (H) than in glabrous (h) seedlings. It is postulated that in R. coreanus factors controlling resistance are linked with An
1 and. probably, with h.Average grades for spur blight (D. applanata) were significantly higher in white-flowered plants in nine out of ten BC1 progenies. Spininess (S) was associated with greater susceptibility in six out of eight BC1 families, although this difference was not statistically significant.Plants with the phenotype hAn
1 on average provided the best source of resistance to both cane spot and spur blight. 相似文献
149.
无刺红树莓组织培养快速繁殖技术研究 总被引:8,自引:0,他引:8
以无刺红树莓带芽茎段和茎尖为外植体,筛选各组织培养阶段高频、稳定的适宜培养基。结果表明:外植体以茎段为佳。分化培养基以1/2 MS 6-BA 1.0 mg/L 活性炭0.1%最好,分化率可达100%;继代增殖培养基以MS 6-BA 1.0 mg/L NAA 0.1 mg/L最理想,增殖倍数可达7倍;生根培养基以1/2 MS IBA1.0 mg/L 活性炭1.0 g/L最佳,生根率可达93.33%。生根类型多为皮部生根。采用2步移栽法进行移裁时,第1次移裁以河砂为基质移栽成活率达到98%,第2次移裁成活率100%。 相似文献
150.
将春、秋两季生长健壮的当年生枝条茎尖,茎段作为外植体.分别在不同激素组合的MS培养基上进行培养.结果表明:春、秋两季的外植体培养能力明显不同.繁殖系数依次为秋季茎尖9.94,春季带芽茎段6.94,春季茎尖4.35,秋季带芽茎段2.28。相同外植体因季节不同.其最适外源激素种类及组合明显不同.秋季茎尖的激素组合为2.4-D 0.1mg/L KT0.1mg/L,单独使用KT或生长素均有利于茎尖萌发;带芽茎段的最适激素组合为2.4-D1.0mg/L KT0.25mg/L;适于春季茎尖的激素组合为6-BA0.25mg/L NAA0.5mg/L.带芽茎段的为6-BA0.25mg/L NAA0.25mg/L。试管苗在生根培养基l/3MS IBA0.1mg/L中生根率达最高为90.5%.最终移栽成活可达85%左右。 相似文献