不同苜蓿品种对叶片愈伤组织诱导及植株再生的影响

以7个苜蓿品种叶片为外植体,采用3种诱导培养基、5种分化培养基,共15个组合,研究了不同品种间愈伤组织诱导及植株再生的差异。结果表明,不同苜蓿品种间植株再生率差异显著,超级13R在7个苜蓿品种中表现最佳。     

早熟耐贮浓黄皮甜瓜品种黄子金玉的选育

黄子金玉是针对目前国内市场栽培面积较大、黄皮、厚薄皮杂交品种丰甜1号类型选育的新型甜瓜品种,通过6代定向选育,结合商品性及抗病力筛选而成的新杂交种。该品种具有黄子标记、抗病能力强、易栽培、极早熟和商品性好等优点;植株生长势强,苗期即比同类品种生长快,叶色深,茎干粗壮,适应性强。     

拮抗细菌菌株B5423-R和Pf7-14在水稻叶片上的定殖及其对土著细菌群体的影响

拮抗细菌菌株Bacillus subtilisB5423和Pseudomonas fluorescensPf 7-14能显著地抑制水稻纹枯病。在温室条件下,通过播种、叶片接种纹枯病菌Rhizoctonia solani,以及在水稻分蘖盛期喷雾菌株B5423-R(B5423的利福平抗性突变体)和Pf 7-14(天然的抗萘啶酮酸菌株)的细菌悬浮液,并通过定期取样、平板系列稀释法回收,监测了菌株B5423-R、Pf 7-14和土著细菌群体在水稻健叶和纹枯病叶上的种群动态。结果表明:在病斑叶片片段(病斑面积占70%~90%),在应用1~7 d后,菌株Pf 7-14的平均群体数量比在相同面积的健康叶片片段上显著性地高3~10倍,而菌株B5423-R的数量比在健康叶片片段上显著性地高12~50倍;土著细菌群体数量在病斑叶片上是健康叶片上的50~60倍。这些结果表明纹枯病病斑大大促进了土著细菌群体和引入的生防细菌的生长,且土著细菌群体和引入的生防细菌在营养和空间上是相互竞争的。     

保靖黄金茶产业现状及发展建议

保靖黄金茶是保靖县古老而珍稀的特异地方优质名茶,独具"香、绿、爽、浓"的优异品质.为充分发挥资源优势,现就保靖黄金茶产业现状和存在的问题,提出保靖黄金茶产业发展的建议.     

Seasonal Changes of Mineral Nutrients in Fruit and Leaves of ‘Newhall’ and ‘Skagg's Bonanza’ Navel Oranges

In southern Jiangxi province of China, ‘Newhall’(Citrus sinensis Osbeck) navel orange presented a conspicuous symptom of boron (B) deficiency in mature leaves, whereas B deficiency symptoms were not manifested on ‘Skagg's Bonanza’(C. sinensis Osbeck) navel orange. In this study, changes in concentrations of B, calcium (Ca), potassium (K), magnesium (Mg), manganese (Mn), and zinc (Zn) were comparatively investigated in the structural parts of the fruit (rind and pulp) and leaves (old leaves from last season and spring-flush leaves from current year) of ‘Newhall’ and ‘Skagg's Bonanza’ navel orange during the growing season. Two peaks of B concentrations were observed in the rind of the two cultivars during fruitlet growth and fruit enlargement, respectively. Boron concentrations were relatively high in the rind during fruitlet growth, and then decreased in both rind and pulp, whereas, during middle and late fruit enlargement significant increases were found for B in both rind and pulp of the two cultivars. Boron concentrations in old leaves of ‘Newhall’ decreased progressively and remained relatively low, whereas that of ‘Skagg's Bonanza’ was relatively high and changed slightly as the season progresses. Both Ca and K concentrations were above the critical threshold values, while their dynamics were reverse to that of B in fruit and leaves during certain times. Old leaf Mg concentrations of samples at 140 days after full bloom from the two cultivars and spring-flush leaves from ‘Newhall’ were below the threshold limit for sufficiency. In addition, Mg in old leaves was much lower from ‘Newhall’ than from ‘Skagg's Bonanza’. Spring-flush leaf concentrations of Mn and Zn and Mn concentrations in old leaves from ‘Newhall’ were relatively lacking during middle and late season, which accelerated the occurrence of B deficiency symptoms on mature leaves of ‘Newhall.’     

三个葡萄品种叶片中激素变化与抗寒性关系的研究

以贝达（抗寒性较强）、赤霞珠（抗寒性中）和梅鹿辄（抗寒性较弱）3个葡萄品种的1 a生枝条为材料,测定不同低温胁迫（-15、5℃）下叶片中4种内源激素ABA、IAA、GA、iPA含量及比值的变化。结果表明：低温条件下,3个葡萄品种叶片中ABA呈现先升高后降低的趋势,而IAA、GA、iPA则显示出先降低后有所升高的变化;ABA与IAA、GA、iPA的比值总体表现出先升高后降低的趋势,并且其变化数值与温度呈负相关。抗寒性强的品种贝达叶片中ABA/GA、ABA/IAA均大于抗寒性差的品种梅鹿辄,其中ABA/GA和ABA/IAA的变化与抗寒性关系最为密切。据此推断,ABA/GA和ABA/IAA可以作为判断葡萄品种抗寒性的指标。     

桃叶片再生不定芽的研究

以桃栽培品种曙光、金童5号和甜桃王试管苗叶片为外植体,研究了基本培养基、植物生长调节剂种类及质量浓度组合、基因型和试管苗继代次数等因素对叶片再生的影响。结果表明,适宜暗培养的培养基为LP+1.5mg·L-1TDZ+0.15mg·L-1NAA;光培养基为LP+0.5mg·L-1TDZ+0.3mg·L-1KT+0.3mg·L-1NAA和LP+0.6mg·L-1TDZ+0.3mg·L-1KT+0.4mg·L-12,4-D;金童5号和曙光具有较强的再生能力,再生率分别为21.8%和14.5%;曙光和金童5号试管苗继代第1～11次叶片的再生能力与继代前3次愈伤组织相比形成率较高;曙光再生苗在培养基1/2MS+0.5mg·L-1NAA上生根率为100%,平均生根条数为7.9。     

壤质土叶面喷施不同养分对强筋小麦产量和蛋白质组分的影响

在壤质土条件下,不同养分叶面喷施对强筋小麦的株高、成穗数影响不显著;叶面喷洒0.1%MnSO4、0.05%(NH 4)2M oO2和0.3%KH 2PO4、2%CO(NH 2)2等能提高强筋小麦的千粒重和产量。喷洒2%CO(NH 2)2和0.1%M nSO4有利于蛋白质和蛋白组分的提高。     

利用组织培养技术向普通小麦导入簇毛麦抗白粉病基因的研究

 对硬粒小麦（T.durum）-簇毛麦（H.villosa）杂种幼胚和F#-1幼穗诱导的愈伤组织进行秋水仙素处理获得硬-簇双二倍体TH1，TH1W，TH2W，TH3，TH3W。平均加倍率为78.8%,最高为94.1%。通过与普通小麦（T.aestivum）回交，幼胚和花药培养，得到了6D/6V异代换系94G22-1，94G25-1，94G32-1，94G33-1。谷草转氨酶（GOT）和酯酶（EST）同工酶可作为这些材料的生化标记。RAPD分析中，引物OPAN3可作为其分子标记引物。     

墨旱莲叶水提取物止血活性初探

[目的]探讨墨旱莲叶水提取物的止血和促凝血活性,为中草药在止血方面的应用提供依据。[方法]将不同剂量的墨旱莲提取物溶液与抗凝兔血混合,测定凝血时间。[结果]墨旱莲叶提取物为0.5%的最适浓度时具有最强促凝血活性,凝血时间为16 s,凝血时间缩短率为99.6%。[结论]墨旱莲叶水提取物有显著的止血和促凝血活性,具有较高的开发利用价值。