莲鞭扦插繁殖初报

1987～1988两年在杭州采用莲鞭扦插法代替传统的种藕繁殖,结果表明,莲鞭扦插具有下列优点:1.节约种藕.扩大繁殖系数.加速良种繁育.2.提高藕田复种指数,3.延长嫩藕上市时间.4.所结的藕体大小比较均匀,适宜作种藕.     

细叶结缕草优质快速繁殖的研究

细叶结缕草是一种优质草坪草种,引入杭州已有40多年历史.这种草不易给籽,一般不用有性方法繁殖,因而导致生活力衰退,无力与杂草竞争.本研究的目的在于改进繁殖技术,使退化的细叶结缕草更新复壮,缩短繁殖周期,由每年出圃一次增加为三次,生产出高质量的毯状草皮或草块.通过两年研究,已达到上述目的.     

Effects of white clover cultivar and companion grass on winter survival of seedlings in autumn-sown swards

The aim was to study the effects of white clover cultivar and combinations with perennial ryegrass cultivars on seedling establishment in autumn‐sown swards and on winter survival of seedlings. Large‐leaved white clover cv. Alice and small‐leaved white clover cv. Gwenda, and an erect and a prostrate perennial ryegrass cultivar were sown in autumn in pure stands and as four binary grass‐clover mixtures. Mixtures of white clover cv. Huia and Aberherald with perennial ryegrass were also sown. Companion grasses had no significant impact on the establishment of white clover. The number of seedlings of white clover cv. Alice in mixtures (335 m^?2) was higher than cv. Gwenda (183 m^?2) and pure swards had similar white clover population densities as mixed swards. White clover cv. Huia tended to have more seedlings than Aberherald (355 and 205 m^?2 respectively). No stolons were produced prior to a severe winter, because of the late sowing date. Winter survival of clover seedlings was 0·56 in mixtures and 0·69 in pure stands, irrespective of white clover or companion grass cultivar. Stolon development of white clover in autumn is often considered essential for overwintering survival and spring growth. In this study, there was considerable survival of the non‐stoloniferous tap‐rooted seedlings of all four clover cultivars despite a severe winter.     

A method to induce polyploids from adult strawberry plants, Fragaria spp., avoiding tissue culture in vitro

A method is described of inducing polyploids in detached stolons using an aqueous solution of colchicine, DMSO and glycerol. The donor plant remains uncontaminated and can be grown further to produce more stolons. The putative colchiploids can be chosen on a morphological basis and confirmed cytologically. About 10% of the treated stolons, starting with diploid and tetraploid strawberry, are converted, but 50% nonviability is caused by the treatment. The method can be applied to some other species and shoot types, using other chemicals with chromosome doubling or reducing effect, or even mutagens. The principle can be used without colchicine treatment to obtain strawberry plants from stolons without contamination of the soil around the main clone.     

马铃薯匍匐茎与块茎建成规律的研究

马铃薯匍匐茎及块茎的建成与光合系统状况及干物质分配密切相关。匍匐茎形成与地上茎生长间存在对光合产物的竞争 ,光合系统的迅速建成有利于匍匐茎和块茎的发生 ;虽然植株的干物质大量分配到匍匐茎和块茎 ,有利于二者的建成 ,但其建成仍然以地上部各器官的建成为物质基础。     

Potato yield enhancement through intensification of sink and source performances

The combined total annual yield of six major crops (maize, rice, wheat, cassava, soybean, and potato; Solanum tuberosum L.) amounts to 3.1 billion tons. In recent years, staple crops have begun to be used as substitutes for fossil fuel and feedstocks. The diversion of crop products to fuels and industrial feedstocks has become a concern in many countries because of competition for arable lands and increased food prices. These concerns are definitely justified; however, if plant biotechnology succeeds in increasing crop yields to double the current yields, it will be possible to divert the surplus to purposes other than food without detrimental effects. Maize, rice, wheat, and soybean bear their sink organs in the aerial parts of the plant, and potato in the underground parts. Plants with aerial storage organs cannot accumulate products beyond their capacity to support the weight of these organs. In contrast, potato has heavy storage organs that are supported by the soil. In this mini-review, we introduce strategies of intensifying potato productivity and discuss recent advances in this research area.     

海月水母螅状体无性繁殖方式观察及一种新发现报道

无性繁殖是水母螅状体有效补充种群数量及扩展栖息地的重要方式,为正确掌握海月水母的无性繁殖方式进而深入了解其生活史,在显微镜下常年观察并详细描述了海月水母螅状体进行匍匐茎生殖、芽体生殖、足囊生殖、繁殖体生殖、纵向分裂生殖和破裂生殖等复杂无性繁殖方式的过程,发现繁殖体生殖可产生浮游态繁殖体芽,在水中漂浮并生长发育成螅状体,新发现一种破裂生殖方式,仅发生在螅状体极度饱食的状态下。对6种无性繁殖方式的行为特征和功能作用进行了对比分析,认为匍匐茎生殖和破裂生殖有利于螅状体种群快速增加个体数量,芽体生殖和纵向分裂生殖有利于子代幼体生长,足囊生殖有利于种群抵御不良的环境条件,繁殖体生殖有利于种群随水流进行长距离迁移,以扩展或转移栖息地。研究表明,不同的繁殖方式是海月水母应对不同环境条件的适应性繁殖对策。     

中国西南部野生狗牙根种质耐寒性初步鉴定

采用田间统计绿期法、电导率法和匍匐茎恢复生长法,对50份西南部野生狗牙根(Cynodon dactylon)和2份美国引进品种(Tifway和Tifeagle)进行耐寒性初步鉴定。结果表明:1) 52份材料的绿期为277～306 d,Sau02033 (越西)、Sau02040 (自贡)的绿期最长;2)半致死温度(LT50)为–9.00～–1.72℃,Sau02014 (金川)、Sau02040 (自贡)的LT50最低;3)匍匐茎恢复生长率为18.05%～42.36%,Sau02012 (金川)、Ly97021 (遂宁)的恢复率最高;4)偏相关分析结果表明,其耐寒性与海拔显著正相关(P <0.05);5)将52份材料系统聚类分为A、B、C三类,耐寒性强弱表现为A> B> C,Tifway和Tifeagle被聚在C类,大部分野生材料的耐寒性高于这两个品种。综上可知,3种方法综合评定结果表明,Sau02040 (自贡)、Sau02013 (金川)、Sau02014 (金川)、XZ2 (察隅)耐寒性较强,具有良好的牧草和草坪草开发潜力,3种指标综合运用更能全面评价狗牙根的耐...     

不同利用强度对混播草地牧草产量与组分动态的影响

目的研究鸭茅+多年生黑麦草+白三叶草地建植适宜播种时期,为其建植和管理提供理论依据。方法以夏季和秋季建植的鸭茅+多年生黑麦草+白三叶草地为对象,分析2个建植时期草地植物种群、群落和土草养分变化特征。结果秋播草地鸭茅重要值较高,夏播草地非播种植物入侵较多,两类草地鸭茅种群小株丛个体储备丰富,大株丛个体数较低,种群总体呈增长型模式;鸭茅株丛密度和白三叶匍匐茎密度、质量和个体大小以及播种禾草地上生物量比例均为秋播草地>夏播草地,而杂类草地上生物量比例、物种多样性和物种分布均匀程度均为夏播草地>秋播草地;土壤有机质和牧草全氮含量为秋播草地>夏播草地。结论秋播鸭茅+多年生黑麦草+白三叶草地建植效果整体较优,可有效抑制杂草生长,利于播种牧草生长和牧草营养价值提高及土壤培肥,适于在研究区及南方相关区域推广。     

GA_3、IAA和C/N对马铃薯试管匍匐茎及试管薯形成的影响

以马铃薯栽培品种中薯３号、大西洋、米拉脱毒试管苗为材料,着重研究了离体条件下,外源激素、培养基Ｃ／Ｎ对匍匐茎发生及试管薯形成的影响。结果表明：①ＧＡ３、ＩＡＡ对诱导匍匐茎发生有明显的作用,处理时间和处理浓度的不同,对试管薯形成有不同的影响,以ＧＡ３０．５ｍｇ／Ｌ＋ＩＡＡ１ｍｇ／Ｌ诱导匍匐茎发生６～９ｄ,再转入结薯培养基培养,单株结薯量最大。②不同Ｃ／Ｎ处理匍匐茎发生数量不同,Ｃ／Ｎ值与成薯指数呈三次抛物线形式变化,Ｃ／Ｎ＝１７．６６９时,成薯指数最大。