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141.
为探索适合于江门地区绿肉节瓜高产栽培的最适间距,选取江玉11号节瓜品种进行行距为60 cm,株距分别为35、45、55 cm的种植密度试验。结果表明,行距60 cm,春季株距35 cm,秋季株距45 cm,为江玉11号节瓜最适间距。 相似文献
142.
植物生长调节剂在茄果类蔬菜上的应用进展 总被引:4,自引:0,他引:4
概述了植物生长调节剂的作用和当前茄果类蔬菜作物栽培中常用生长调节剂的种类、主要作用及其调控生理基础,指出了植物生长调节剂使用应注意的问题及其应用前景。 相似文献
143.
以多年生黑麦草(Lolium perenne L.)成熟种子作为外植体,建立其高频再生体系,通过农杆菌介导法将磷酸烯醇式丙酮酸羧化酶(PEPC)基因转入,为多年生黑麦草的抗逆转基因工作奠定基础。结果表明:种子充分灭菌后在附加6.0 mg·L-1 2,4-D的培养基中诱导愈伤组织,诱导率可达61.33%。愈伤组织在2,4-D浓度减半的培养基上继代培养长势良好,分化培养基为MS培养基附加1.0 mg·L-16-BA,分化率最高达到61.33%,在1/2 MS+0.5 mg·L-1 NAA培养基中进行生根培养,生根率达100%。以该再生体系为基础,将获得的愈伤组织作为外植体进行遗传转化,经筛选培养后得到再生植株,通过PCR及实时荧光定量(Real-Time)PCR验证表明PEPC基因已成功转入,转化率为8.67%。试验结果将为多年生黑麦草抗性品种的研究奠定基础。 相似文献
144.
在室内外调查研究的基础上,应用生物多样性基本原理,首次论述了库尔勒市区草坪植物区系、染色体遗传、生活型、生态型、植物景观和资源植物的多样性及其质量特征。结果表明,库尔勒市区草坪植物的多样性,在植物物种组成上,以人工栽培和引种为主,本土杂草为辅;在地理成分上,以本土地理成分为主,外引地理成分为辅;在染色体组型上,以单染色体组型为主,多染色体组型为辅;在生活型组成上,以木本植物为主,草本为辅;生态类型组成上,以中生为主,旱生为重要组成部分,湿、水生为补充;在植物景观组成上,以2、4、5要素景观为主,1、3要素景观为辅;在资源植物构成上,以环境和生产类为主,食用和特殊类为辅。 相似文献
145.
典型草原区植物群落结构特征动态监测 总被引:1,自引:0,他引:1
1999-2002年在内蒙古锡林郭勒盟白音锡勒牧场典型草原区海流特,监测主要植物群落结构特征。结果表明,随时间推移,试验区主要群落的优势植物大针茅、羊草相对高度、相对盖度、相对密度和相对生物量呈降低趋势,退化指示植物冷蒿、狼毒相对高度、相对盖度、相对密度、相对生物量呈增加趋势;试验区群落物种丰富度指数、多样性指数和均匀性指数随时间推移均呈降低趋势;围栏在试验区草地植物群落特征的保持方面很有效,但围栏内植物群落特征随时间推移仍呈退化趋势。 相似文献
146.
Cultural ecosystem services related to urban green spaces contribute significantly to liveable cities. While previous studies highlight the intersection of cultural ecosystem services with societal values, spiritual or religious values associated with urban nature have received less attention. In India, as in other parts of the world, sacred sites are known for their biological richness, but analyses from urban sacred sites are largely missing. Based on a stratified random sampling approach, we analysed the cultivated and wild plant species assemblages of 69 sacred sites in the megacity of Bengaluru, India, in relation to biological and cultural features, and parameters related to the urban matrix and type of sacred sites (temple vs. katte). Unlike other urban studies, we found a dominance of native species in the cultivated and spontaneous species pools (121 species in total), with Ficus religiosa and Azadirachta indica as most frequently planted species. Culturally relevant species prevailed in the species pool (89%), with overlaps between religious (36%), medicinal (50%) and ornamental (62%) plants; only 11% of species were weeds. Urban matrix parameters (age of development, housing density) and size and type of sacred sites were related to differences in species assemblages. We identified key species for different classes of age and housing density, and for types of sacred sites. Our study demonstrates that urban sacred sites have an important potential in harbouring both native and culturally significant species that can support urban livelihoods in developing countries by a range of cultural and provisioning ecosystem services, including medicinal uses. As such sites are conserved by communities for spiritual or cultural beliefs, local biodiversity can be enhanced, e.g. by adapting management practices through community participation. This would strengthen the important contribution of sacred sites within the green infrastructure of rapidly growing megacities. 相似文献
147.
148.
日粮中添加沸石对肉兔生长的影响 总被引:2,自引:1,他引:2
为探讨沸石对肉兔生长的影响,将40只60~70日龄加利福尼亚幼兔随机分成4组。Ⅰ组为对照组,饲喂基础日粮,另外3组分别在基础日粮中添加3%、6%和9%沸石。结果表明,在每千克饲料含可消化能110MJ、粗蛋白质160%的日粮中,添加3%~5%的沸石,可促进幼兔生长,降低饲养成本,提高养兔效益。 相似文献
149.
The objective was to assess the effect of banding or burdizzo castration performed on farms on plasma testosterone, acute-phase proteins, scrotal circumferences, growth, and well-being of bulls. 243 Continental bulls (12 months; 399.2 ± 5.72 kg) from three different farms were allocated at random, after stratification on weight within breed type, to one of three treatment groups: banding castration (BAND; n = 80), burdizzo castration (BURD; n = 83), or controls (CON; n = 80). The castration methods were conducted under local anaesthesia, and tetanus toxoid vaccine and antibiotic were also injected at castration. BAND and BURD castrates had lower (P < 0.001) plasma testosterone concentration than control bulls, with no difference between BAND and BURD castrates on 28 d post-castration. From days 0 to 14 post-castration, BAND (P = 0.0002) and BURD (P < 0.0001) castrates had lower average daily gain (ADG) than CON bulls, no difference (P = 0.46) was found between BAND and BURD castrates. From days 15 to 28, BAND castrates had lower ADG compared with BURD castrates (P = 0.03) and CON bulls (P = 0.01), while no difference (P = 0.76) was found between BURD and CON. From days 29 to 56, BAND (P = 0.01) and BURD (P = 0.002) castrates had lower ADG than CON bulls, no difference (P = 0.55) was found between BAND and BURD. From days 57 to 84, the ADG of BAND castrates was not different compared with BURD castrates (P = 0.12) and CON bulls (P = 0.38), while BURD had lower (P = 0.02) ADG compared with CON. The integrated ADG from day 0 to 112 of BAND (P = 0.0001) and BURD (P = 0.02) groups were lower compared with CON, while there was no difference (P = 0.09) between BAND and BURD castrates. On d 14 post-castration, BAND castrates had lower scrotal temperature than BURD (P < 0.0001) and CON (P < 0.0001), and BURD castrates had greater (P < 0.006) scrotal temperature than CON; BAND castrates had lower scrotal latitudinal and longitudinal circumferences than BURD castrates (P < 0.001) and CON bulls (P < 0.001), and BURD castrates had greater (P < 0.001) scrotal latitudinal and longitudinal circumferences than CON bulls. BAND (P < 0.0001) and BURD (P = 0.01) castrates had greater glucose concentration than CON bulls, and BAND castrates had greater (P = 0.04) glucose concentration than BURD. In conclusion, BAND or BURD castration significantly reduced plasma testosterone concentration; reduced average daily weight gain mainly during the first 2 weeks, which was not compensated during the subsequent 16 weeks; increased withdrawal of stored energy and increased plasma protein concentration. BURD showed an advantage over BAND in growth during days 15 to 28 following castration. 相似文献
150.