On the senescence of ovules in cherries

The longevity of ovules in sweet and sour cherries has been studied in vivo, using a fluorescence—microscopic method which enables one to determine the viability of ovules at a very early stage. It was found that ovules which were not fertilized became progressively senescent 4 to 5 days after anthesis, and about a week after flower opening a rather high percentage of the ovules was non-viable.Applied growth regulators usually enhanced senescence of the ovules, especially GA₃. Even those that delayed senescence of the external flower parts, e.g. 2,4-D, benzyladenine and kinetin, accelerated the ageing of ovules in most instances. No substance was found which extended the longevity of ovules in cherries.     

香蕉愈伤组织及体细胞胚诱导过程中的组织学观察

将巴西蕉(Musa AAA Cavendish)的未成熟雄花接种在MI培养基(MS+4mg/L2,4-D+1mg/L生物素+1mg/LIAA+1mg/LNAA+100mg/L谷胺酰氨+100mg/L麦芽抽提物+30g/L蔗糖+7.5g/L琼脂粉)上进行愈伤组织诱导,对愈伤组织诱导过程中的各个阶段进行组织学观察。结果表明,未成熟雄花外植体脱分化的起始部位是表皮下层的维管组织细胞,启动时间为外植体接种后4～5周;外植体接种8周后获得分生小球体;胚性愈伤组织形成于分生小球体的表面,主要由具有细胞核和核仁比大、细胞质丰富的胚性细胞组成。随着培养时间的延长,胚性愈伤组织的表面形成一些由多细胞组成的体细胞原胚,有时还可观察到二分体的存在,这表明香蕉体细胞胚可能是单细胞起源的。     

葡萄保鲜技术研究进展

综述了近年来葡萄贮藏的主要技术现状和研究状况,包括冷藏、气调贮藏、保鲜剂应用、臭氧处理等方面,提出了葡萄贮藏保鲜技术的研究方向。     

薰衣草叶片高频再生体系的建立

 以薰衣草叶片为外植体进行了离体再生研究。结果表明: 叶片愈伤组织诱导最佳的培养基是MS + 2,4-D 0.1 mg/L + 6-BA 0.5 mg/L, 诱导率高达100%; 液体悬浮—固体培养芽分化率达92.5% , 芽数/愈伤组织达6.6; 正交试验筛选出芽增殖最佳培养基为MS +NAA 2.0 mg/L + 6-BA 0.5 mg/L + IAA 1.0 mg/L, 其增殖系数高达8.7; 在芽增殖培养基上可直接生根, 生根率达100%。     

Consequences to fertilization of the developmental stage of apricot ovules at anthesis

Summary

Flowers at anthesis from the apricot cvs Palstein and Goldrich were examined to determine their ovule maturity stage. Further, flowers from both cultivars were pollinated and collected after 2000 and 3000 growing degree hours (GDH) in two consecutive years. Numbers of fertilized ovules were recorded in those flowers. Ovules of ‘Palstein’ from flowers at anthesis showed predominantly an embryo sac at the eight nuclei stage of development while embryo sacs in ‘Goldrich’ were mainly in a four nuclei stage. After 2000 GDH from pollination 90% of viable ovules were fertilized in ‘Palstein’ whereas only 37.5% of them were fertilized in ‘Goldrich’. After 3000 GDH, Goldrich presented the same percentage of fertilized ovules that was recorded after 2000 GDH. Non-fertilized ovules did not degenerate and developed normally in pollinated and non-pollinated flowers from both cultivars. Further, non-fertilized pollinated flowers were not different from non-pollinated flowers in the development of the embryo sac, indicating that the chances for fertilization would not be increased by pollination in apricot. We suggest that the lack of fertilization in ‘Goldrich’ is due to degeneration of the male gametophyte, which would have a limited life, not long enough for the embryo sacs to develop to maturity.     

巴西香蕉薄切片丛生芽途径高频再生体系的建立

香蕉是世界上重要水果之一,但它在栽培过程中常受到病毒、真菌等的危害。以吸芽生长点为外植体进行脱毒培养可以得到大量的脱毒苗,20世纪80年代后,这一技术被广泛应用于香蕉种苗的规模化生产。但在香蕉产区,脱毒苗在种植后仍会受到花叶心腐病、束顶病等危害。采用现代转基因技术将抗病性基因导入香蕉,培育出具有抗病性的香蕉品种是提高香蕉抗病性最有效的手段之一,而建立有效的转化体系是进行转基因成功的关键。为此,笔者进行了本试验。通过愈伤组织再生植株途径建立香蕉遗传转化体系的难度大,成功的报道少。而利用香蕉假茎薄片为外植体进行…     

The effect of different temperatures on the viability of ovules in cherries

The effect of different temperatures on the senescence of ovules was investigated in 2 sweet and 3 sour cherry cultivars using a fluorescent-microscopic method. Detached twigs were kept in growth chambers at constant temperatures of 5, 10, 15 or 20°C. Increasing temperature substantially shortened the viability of the ovules. At 5°C, most ovules were senescent 5 days after anthesis, and at 20°C this period was shortened to 1–2 days.     

西瓜未受精子房离体培养技术

西瓜未受精子房离体培养作为单倍体育种的有效方法,可极大提高育种效率。以西瓜‘早佳’未受精子房为试材,对西瓜未受精子房出胚率的影响因素进行了研究,并鉴定了再生植株倍性。试验结果表明,栽培季节对西瓜未受精子房离体培养有很重要的影响,在相同的培养条件下,秋季栽培出胚率可达21.33%,高出春季栽培约6%;取材当天的日最低、最高气温对西瓜未受精子房离体培养出胚率也有一定的影响,在21～35℃范围内日平均出胚率均可达10%,显著高于过低或过高气温下统计的出胚率;4℃低温预处理并不能提高西瓜胚状体诱导效率。利用染色体计数法与流式细胞仪鉴定36棵再生植株倍性,单倍体率为97%、二倍体率为3%。     

青花菜DH系带柄子叶高频再生体系的建立

以青花菜DH系3-6、3-7和3-9带柄子叶为外植体,研究其高频离体再生体系,比较了不同基因型、不同质量浓度植物生长调节剂、不同时期苗龄外植体及不同浓度AgNO3添加剂对不定芽再生频率的影响。结果筛选出3-6和3-7两个基因型：8 d苗龄外植体不定芽的再生频率分别为96.9%和97.8%（培养基：MS+0.02 mg·L-1 NAA+1.0 mg·L-1 6-BA+4 mg·L-1 AgNO3 +10 g·L-1琼脂+30 g·L-1蔗糖）,平均外植体的再生芽数分别为15、14个,生根培养诱导生根率均为100%（培养基：1/2MS+0.05 mg·L-1 NAA + 7 g·L-1琼脂+30 g·L-1蔗糖）,驯化移栽成活率均达100%。     

Effects of Denapon and Ethrel on thinning grapes

The effectiveness of Denapon and Ethrel as a thinning chemical for ‘Muscat of Alexandria’ grape was examined from 1980 to 1982 with various timings and concentrations of application. Ethrel applied at 50 mg l^?1 by cluster-dipping or shoot-spraying at full bloom, or 6 days after full bloom, resulted in over-thinning and chemical injury, and no thinning effect was found when Ethrel was applied at 10 or 5 mg l^?1 on the same dates. The only treatment which exhibited a desirable thinning effect was shoot-spraying at 50 mg l^?1 12 days after full bloom, but this markedly inhibited berry growth. Denapon applied at 1667 mg l^?1 by shoot-spraying at full bloom, or 6 days after full bloom, reduced the number of berries per cluster almost adequately and consistently without any unfavorable side effects. This chemical applied at 834 mg l^?1 was nearly as effective as when applied at 1667 mg l^?1, but the effectiveness of the former was less consistent than that of the latter. From these results, Denapon is thought to be a promising thinning chemical for ‘Muscat of Alexandria’.     

Growth and development of ovules of banana,plantain and enset (Musaceae)

Sterility has profound effects on the development of reproductive tissues in members of the Musaceae and limits genetic improvement required to deal with new diseases. Ovules of seeded diploid Musa acuminata (AA) and edible triploids (AAA) from the same cytogenetic group, plus edible triploids containing genomes of the M. balbisiana cytogenetic group (AAB, ABB) and the related genus Ensete sp. were studied to determine the effects of sterility on the growth and development of the ovule and its tissues. Specimens were collected from subtropical and Mediterranean environments in Australia.At anthesis, the ovules of triploid plants were 36% larger than the ovules of diploid plants. The diploid ovules ceased growth shortly after the inflorescence emerged from the pseudostem. In contrast, the triploid ovules continued to grow 7–10 days past anthesis, increasing in size by 70%.All ovules of diploid M. acuminata ssp. had an embryo sac at anthesis, against 97% for triploids. At anthesis the embryo sacs in diploid ovules occupied 2.7% of the nucellus compared with 1.5% in triploid ovules. The embryo sacs did not grow between bunch emergence and anthesis, once formed they maintained the same size. Many embryo sacs were not positioned correctly, flush with the nucellar cap. The diploid M. acuminata ssp. had 75% of embryo sacs correctly positioned against 10% in the edible triploids. The proportion of balbisiana genome (B) did not affect ovule or nucellus size or shape, or cell number across the nucellus. It increased the embryo sac presence 96–100% of ovules.The sterile edible triploid bananas have embryo sacs at anthesis but many are incorrectly positioned, which may contribute to their sterility. The balbisiana genome in the edible triploids was associated with a 2.4-fold increase in the number of correctly positioned embryo sacs and this may contribute to the increased fertility associated with the B genome.     

中国野生葡萄副梢长度的RAPD标记

为培育短副梢葡萄品种,对中国野生葡萄副梢长度性状进行调查,以葡萄短梢×长梢的葡萄种间杂交组合(燕山-1×河岸葡萄)F183个单株为试材,采用BSA法和RAPD技术,通过369个随机引物的筛选,获得了1个与中国野生葡萄副梢长度基因连锁的RAPD标记OPB07-2000,并在中国野生葡萄17个种46个株系中得到验证。这就为葡萄短副梢分子辅助育种提供了科学依据,进而从根本上解决葡萄生产上夏季副梢生长过旺的问题。     

葡萄香气物质及其影响因素的研究进展

香气是衡量葡萄和葡萄酒品质的重要指标。葡萄果实及葡萄酒香气的化学成分主要包括萜烯类化合物、降异戊二烯衍生物、芳香族化合物、挥发性脂肪族化合物、含硫化合物和吡嗪类化合物。这些化合物含量、性质及相互之间的平衡,对葡萄及葡萄酒的香气品质具有决定性作用。综述了几种常见香气物质在葡萄及葡萄酒中的特点和含量,并从内因和外因两个角度综述了各种因素(品种、栽培技术、环境条件等)对葡萄果实的香气物质组成及含量的影响,认为干燥的砂质土壤,适当的曝光,冷凉的气候,生长势弱的砧木等更有利于香气物质的形成,同时分析了各种影响因素的研究现状和目前的研究热点。     

In vitro somatic embryogenesis from Mangifera indica L. callus

The nucellus and globular adventitious proembryos were removed from 2-month-old fruits of mango (Mangifera indica L.) cultivars ‘Ono’ and ‘Chino’, and were cultured on sterile, solid Murashige and Skoog (MS) medium that had been modified as follows: half-strength major salts and chelated iron; 20% (v/v) coconut water (CW); 6% sucrose; 100 mg l^?1 ascorbic acid and 400 mg l^?1 glutamine. Embryogenic explants were sub-cultured after 4–6 weeks in liquid modified MS medium containing 2 mg l^?1 2,4-dichlorophenoxyacetic acid (2,4-D) instead of CW. Rapidly growing cultures were established and were sub-cultured monthly. Somatic embryogenesis was induced following sub-culture from MS medium with 2,4-D to MS without growth regulators and with or without activated charcoal (0.5%). Germination of somatic embryos appeared to be enhanced by 1 mg l^?1 benzyladenine (BA); however, most of the germinating embryos became embryogenic.     

薄膜温室葡萄花芽分化规律的研究

通过对薄膜温室2～4年生巨峰、无核白鸡心葡萄整个生育期花芽分化的观察,研究薄膜温室葡萄花芽分化的规律。结果表明,巨峰与无核白鸡心在早期升温条件下,花芽分化比例低,二轴分化程度较浅,不能形成完整的花芽;花芽的形成与树体的营养状况有关。花芽分化开始时磷素水平下降明显,蛋白质含量也有下降,二轴分化期后开始回升,磷素水平也显著提高;更新后花芽的分化与叶龄有关,当叶龄达15d时,开始出现花序原基,叶龄达27d时出现二轴分化期,二轴分化盛期为叶龄46d,花芽分化率平均为91.1%。温室巨峰、无核白鸡心葡萄栽培时,花芽需要靠更新后的新梢形成,因此,加强更新后的新梢管理是达到稳产的关键。     

西瓜未受精胚珠离体培养若干影响因素的研究

为探讨适宜的西瓜未受精胚珠离体培养方法,以‘大果黑美人’、‘早春翠玉’、‘中科6号’等为试材,研究了供体植株的基因型、4℃预处理时间、35℃高温预培养时间及植物生长调节剂对未受精胚珠的反应率和愈伤诱导率的影响。结果表明:不同材料(基因型)的胚珠反应率和愈伤诱导率都有显著性差异,愈伤诱导率最高的是‘中科6号’(92.3%),最低的是野生西瓜‘09005’(57.2%);4℃低温预处理没有显著提高胚珠反应率和愈伤诱导率,对于胚珠反应率和愈伤诱导率的影响因培养基不同而不同;35℃高温预培养可以提高胚珠反应率和愈伤诱导率,预培养3 d可以得到较高的愈伤诱导率和质量较好的愈伤组织;在诱导培养基MS+6-BA 2 mg·L-1+NAA 3 mg·L-1+TDZ0.05 mg·L-1上,愈伤诱导率最高为84.64%;植物生长调节剂TDZ相对于2,4-D和KT对西瓜未受精胚珠愈伤诱导的效果较好。     

The association between low temperatures and anatomical changes in preanthetic ovules of Musa (Musaceae)

Bananas growing in subtropical environments suffer tissue malformation in fruit structures that is associated with mean daily temperatures of about 14 °C during differentiation of the fruit tissues. Low temperatures may also affect the pre-anthetic ovules and contribute to loss of functionality in reproductive structures. Ovules of Musa acuminata Colla ssp. that experienced a range, 3–18 °C, of minimum temperatures in the field, were examined for anatomical changes. We assumed that low temperatures caused the changes by association with the gross abnormalities of flower structure described in the literature. The first sign of anatomical changes in ovules associated with low temperature was the protrusion of the nucellus and nucellar cap through the micropyle forming a tongue, which often contained the embryo sac. Malformed ovules were found next to normal ones, especially in ovaries that displayed no outward signs of malformation associated with low temperatures.The ovules affected by low temperature were smaller, grew less between developmental stages and remained more round towards anthesis than those that were unaffected. Affected ovules had smaller female gameotphytes that occupied a reduced proportion of the nucellus. In addition, the distance between the embryo sac and the nucellar cap increased, however the number of intervening cells did not. The nucellar cells in the tongue were squashed longitudinally. Malformations of ovules were observed in bunches emerging in the autumn and winter as well as spring, associated with low temperatures at a critical period in the few weeks before anthesis when the archesporia and megaspore were formed.     

夏季摘心对葡萄花芽分化的影响

该试验以二年生87－1葡萄为试材，采用石蜡切片法研究了夏季摘心对葡萄冬芽和夏芽花芽分化的影响，以掌握摘心后葡萄花芽分化的规律和形态特征，从而进行人为调控，生产出优势的反季节果品，试验结果表明，摘心前花芽分化速度较慢，甚至未分化，摘心后，夏芽在2天内，甚至在冬芽与夏芽未分开时就已分化出一个花序原基，平均2d可展一片叶，6d就可看见第三叶对面的小花序，在未除去副梢的情况下，冬芽12－14天也可分化出一个花序原基，如果完全除去副梢或留一片叶反复摘心，其分化速度会更快。     

不同灌水条件对设施葡萄果实品质的影响

为寻求设施葡萄各生育期的最佳起始灌水阈值与灌水量,采用正交试验设计,在萌芽至花期(A)、幼果发育期(B)、果实转色成熟期(C)、果实采收至落叶期(D)分别设置3个水分梯度,共9个处理,于果实成熟期测定果实品质并综合评价,以此研究不同灌水条件对果实品质的影响。结果表明,果实品质受灌水时期、起始灌水阈值、灌水量的共同影响,在萌芽至花期、果实转色成熟期保持高起始灌水阈值与高灌水量,在幼果发育期降低起始灌水阈值同时适当增加灌水,在果实采收至落叶期降低起始灌水阈值同时减少灌水,获得的果实品质指数最大,综合品质最佳。同时得到理论灌水方案为A_2B_3C_2D_1,即4个时期的土壤相对含水量分别为70%～80%、60%～80%、60%～70%、55%～65%。     

Direct somatic embryogenesis and plant regeneration from leaf cultures of ornamental species of Dianthus

Protocol for direct somatic embryogenesis from leaf explants of economically important species of Dianthus, viz. D. caryophyllus, D. barbatus and D. chinensis has been developed. Murashige and Skoog’s (MS) liquid medium supplemented with 2,4-D (1 mg/l) was used for direct induction of somatic embryogenesis without an intervening callus phase. Initially globular structures were observed after 21 days of culture of leaf explants in liquid medium. Development of embryos to heart and torpedo stages was achieved in the liquid medium incorporated with polyethylene glycol (PEG 6000) at a concentration of 2.5%. Embryo maturation was further promoted by addition of casein hydrolysate (CH) (200 mg/l) in MS liquid medium. Embryos germinated to form plantlets on solid MS medium supplemented with GA₃ (1 mg/l). Regenerated plants with well-developed root and shoot systems were successfully transferred to field conditions.