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311.
Microspores from a highly anther culturable rice line (Oryza sativa L. spp. indica) derived from the anther culture of F2 hybrids of photoperiod-sensitive male-sterile rice, after 7 days of low temperature treatment and another 7 days of preculture within anthers, were isolated mmechanically. They were cultured in Ne medium containing 3% manitol, 6% sucrose, 5 g/L inositol, 100 mg/L serine, 800 mg/L glutamine, 1 000 mg/L L-proline, 10% (V/V) coconut milk and 2 mg/L, 2,4-D, and 1 mg/L kinetin. After 5 days, microspores initiated first division and subsequently developed into multicellular pollens and calli. Green plant could be recovered when compact calli were transferred onto agar-solidified MS medium containing 3% sucrose, 0.5 mg/L kinetin, 2 mg/L 6-BA and 1 mg/L IAA. 相似文献
312.
Bishnoi U.S. Jain R.K. Gupta K.R. Chowdhury V.K. Chowdhury J.B. 《Plant Cell, Tissue and Organ Culture》2000,61(2):153-159
An improved procedure has been developed for high frequency androgenesis in indica × Basmati rice hybrids using a liquid culture
medium. Anthers from fourteen genotypes comprising of indica × Basmati rice F1 hybrids, F2 plants and the parental rice cultivars, were floated in liquid RZM, N6M, and Heh5M media. Anther culture frequencies (percentage
of anthers forming calluses) in most of the genotypes were significantly higher in RZM medium (16–75%) compared to those obtained
in N6M (7–29%) and Heh5M (7–41%) media. Agarose (1.0% w/v)-solidified MSR1 medium containing 3.0% (w/v) maltose, 1 mg l−1 kinetin, 1 mg l−1 6-benzyladenine (BA) and 0.5 mg l−1α-naphthalene acetic acid (NAA) induced green shoot regeneration at high frequencies compared to the medium (MSR2) lacking
BA. In all the genotypes, microspore calluses initiated in RZM medium regenerated green shoots with over tenfold higher frequencies
compared to the calluses initiated in other two media. High plant regeneration frequencies (up to 270 green plants/1000 anthers)
were obtained from microspore-derived calluses of some of the F1 hybrids (Gobind × Basmati 370, Gobind × Taraori Basmati) and F2 plants (Gobind × Basmati 370, Gobind × Taraori Basmati, HKR86-3 × Taraori Basmati) as compared to their actual parents. Cytological
analysis of the root tips of the progeny seedlings of the microspore-derived plants revealed haploids at a frequency of about
50%; 22% of the microspore- derived plants had > 5% spikelet fertility and were diploid. Use of RZM liquid and MSR1 media,
respectively for anther culture and plant regeneration resulted in several fold increase in the recovery of green plants from
recalcitrant indica × Basmati rice F1 hybrids/F2 plants which were comparable to those reported for japonica rice varieties/hybrids leading to the improved feasibility of
using doubled haploids in genetic, breeding and mapping research with indica rice.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
313.
水分胁迫对芒果(Mangifera indica L.)幼叶细胞活性氧伤害的影响 总被引:21,自引:1,他引:20
对芒果进行了水分干旱胁迫处理,结果表明,水分胁迫使芒果幼叶的相对含水量RWC(rel-ative wate content)和叶水势ΨT下降,芒果幼叶的超氧离子O^-2产生速率随水分胁迫处理强度加大而增加,丙二醛MDA(malondialdehyde)含量的变化趋势与O^-2产生速率的变化趋势相似超氧经歧化酶SOD(superoxide dismutace),这氧化物酶POD(peroxidase 相似文献
314.
甘蓝型油菜与蔊菜的原生质体融合与植株再生 总被引:1,自引:0,他引:1
以甘蓝型油菜下胚轴和蔊菜叶片为外植体提取原生质体, 采用PEG-高pH、高Ca2+附加DMSO的原生质体融合方法, 用液体浅层静置培养融合体, 获得了10株融合杂种, 观察了杂种形态学和细胞学。结果表明:1%纤维素酶+0.2%离析酶+3 mmol/L MES 酶解14 h 可获得较高产率的油菜原生质体, 0.25% 纤维素酶+0.5%离析酶+5 mmol/L MES酶解12 h可获得较高产率的蔊菜原生质体; 30% PEG + 0.3 mol/L葡萄糖+50 mmol/L CaCl28226;2H2O +15%DMSO的融合条件下, 获得了10.4%的融合率; 实验所获的原生质体融合材料可作为新种质。 相似文献
315.
匍匐茎草本蛇莓对基质养分条件的克隆可塑性 总被引:18,自引:0,他引:18
A pot experiment with three levels of nutrient (N, P, K) supply was carried out to investigate clonal plasticity of stoloniferous herb Duchesnea indica Focke in response to nutrient availability. The plants had greater biomass at higher levels of nutrient availability. The root/shoot ratio of the plants changed with the nutrient availability in the following order: low level > high level > medium level. They had the largest biomass allocation to stolon at the medium level of nutrient availability. The biomass allocation to petiole did not respond to the treatments. The plants formed more stolons and ramets at the high and medium levels than the low level of nutrient availability. The petiole length, specific petiole weight(mg/cm)and stolon internode length of the plants did not respond to the treatments, while the specific stolon weight (mg/cm)of the plants was greater at the high and medium levels than the low level of nutrient availability. The results have been discussed in the context of adaptation of clonal plants to environmental heterogeneity. 相似文献
316.
籼稻品种浙辐802抗瘟性遗传研究 总被引:7,自引:0,他引:7
通过与8个日本鉴别品种杂交和利用日本代表菌系研54-04及我国南方稻区菌系95-h接种鉴定,研究了籼稻品种浙辐802的抗性遗传。研究结果表明,该品种对菌系研54-04的抗性由 2对显性基因控制,对菌系 95-t2的抗性由 1对显性基因控制。基因等位性分析确认,浙辐802中抵抗95-t2的抗病基因与Pi-i基因等位,与Pi-a、Pi-sh、Pi-k、Pi-z、Pi-b、Pi-t、Pi-ta等已知基因位点为非等位关系;抵抗菌系研54-04,感染菌系95-t2的基因与Pi-i、Pi-k、Pi-b、 Pi-t 4个已知基因位点为非等位关系。对这个基因与其他已知基因的等位性进行了分析,认为它可能是1个未被命名的新基因。 相似文献
317.
318.
本文通过对十字花科常见杂草芹菜[Rorippa in lica(L.)Hiern]在南京地区的自然群体的周期性观察,以了解其在不同生态环境下的生活周期。本文还通过一系列实验来观察其繁育系统、种子传播的动因、结实力、种子发芽率和植物抗人为干扰的耐受性。花蕾套袋试验证明蔊菜主要是自交可亲和的,即使存在异型杂交也是微不足道的。种子传播效应试验揭示水和风都是种子传播的自然力。该种具有范围很广的耐受性,踏践和刈割试验证明在严重的人为于扰下仍能完成其生活周期。蔊菜尽管本质上属于多年生草本,能产生大量的种子,在很大程度上靠种子繁殖。种子萌芽试验证明它的种子萌发参差不齐。总之,蔊菜具有典型杂草的许多特性,而这些特性给它以适合在多种自然的和人为干扰的环境中正常地生长的能力。 相似文献
319.
在控制光长与温度的人工气候室,研究了7个核不育系籼稻抽穗与结实的光、温反应特性。二九青S、安农S-1、衡农S,CY8526S,W6154S,KS-14植株抽穗的感光性均弱,光周期敏感期(PSP)为-6至8天,仅8902S中等,PSP为31天,抽穗的高温促进率(TSR)一般为20%左右,感温性均属中等:KS-14为41%属强级。它们结实对光周期一般不敏感,仅二九青S、CY-8526S8902S在LD下结实率明显下降,但未达到全不育程度,因此均不是光敏核不育系;它们结实对温度均极敏感,30℃高温下5个品系全不育,W6154S在高温与20℃低温下都近于全不育;衡农S则在低温下近于全不育。供试7个不育系全为温敏不育系,它们结实的最适温度范围相当狭窄。 相似文献
320.
- 1. 1. Results of a study on lethal and sublethal responses of different size groups of the tropical brown mussel, Perna indica, when exposed to different temperatures are presented.
- 2. 2. Exposure to a temperature of 38°C showed 100% mortality of 9 mm size group mussels in 120 min.
- 3. 3. Mortality was dependent on age (size) of the mussels, young ones being more susceptible than older ones.
- 4. 4. All size groups showed a progressive reduction in physiological activities such as filtration rate, foot activity and byssus thread production when temperature was increased from 30°C.
- 5. 5. This study suggests that heat treatment is an attractive alternative to chlorination for mussel fouling control in tropical power stations.