Clone identification and genetic relationship among vine cacti from the genera Hylocereus and Selenicereus based on RAPD analysis

Clones of Hylocereus and of Selenicereus species were distinguished from each other by the banding pattern generated by one to nine 10-mer oligonucleotide primers in the random amplified polymorphic DNA (RAPD) reaction. RAPD analysis was also applied to estimate the genetic relationship among five Hylocereus and nine Selenicereus species. A dendrogram was constructed based on a data matrix of 173 polymorphic bands originated by nine primers. Two groups were identified, one consisting of Hylocereus species and the other consisting of Selenicereus species. These results are consistent with the accepted taxonomic classification of the genera studied. The principal coordinate analysis (PCO), i.e. the plot drawn on the basis of the RAPD data, clearly distinguished between three groups, namely, Hylocereus species, S. megalanthus and the rest of the Selenicereus species studied. PCO thus strongly support the notion that the tetraploid S. megalanthus is an exception among the Selenicereus group. The RAPD results support our hypothesis regarding the allopolyploid (rather than autopolyploid) origin of this species.     

Treatment of contaminated radial fracture in Sprague-Dawley rats by application of a degradable polymer releasing gentamicin

Fracture-related infections remain a leading cause of morbidity and mortality. We aimed to establish a simple contaminated radial osteotomy model to assess the efficacy of a biodegradable polymer poly(sebacic-co-ricinoleic acid) [p(SA-RA)] containing 20% w/w gentamicin. A unilateral transverse osteotomy was induced in Sprague-Dawley (SD) rats, followed by application of Staphylococcus aureus suspension over the fracture. After successfully establishing the contaminated open fracture model, we treated the rats either systemically (intraperitoneal cefuroxime), locally with p(SA-RA) containing gentamicin, or both. Control groups included non-contaminated group and contaminated groups that were either untreated or treated with the polymer alone. After 4 weeks, the bones were subjected to micro-CT scanning and microbiological and histopathology evaluations. Micro-CT analysis revealed similar changes in the group subjected to both local and systemic treatment as in the non-contaminated control group. Lack of detectable bacterial growth was noted in most animals of the group subjected to both local and systemic treatment, and all samples were negative for S. aureus. Histopathological evaluation revealed that all treatment modalities containing antibiotics were highly effective in reducing infection and promoting callus repair, resulting in early bone healing. While p(SA-RA) containing gentamicin treatment showed better results than cefuroxime, the combination of local and systemic treatment displayed the highest therapeutic potential in this model.     

保持产量提高蕃茄品质的盐水灌溉

以两种不同稀释浓度的海水(3和6西门子/米)滴灌“PClll”蕃茄,分别在第一片真叶(早期)和第一个裂果出现(晚期)时进行。一般而言,盐分提高了风味、可溶性固形物及糖的浓度,减少了色斑。因而提高了果实的总体品质,货架寿命未受盐处理的影响。最重要的发现是:在植物发育后期,用低浓度盐水灌溉,其总产量与对照相比无实质性的差异、达出口质量的产量相同,而果食的品味远比对照好。沙漠地区温室栽培的蕃茄,采用盐水灌溉的方法提高果食品质是可行的。     

The potential of ripening mutants for extending the storage life of the tomato fruit

Summary The effect of the fruit ripening mutants rin, gr, nor and Nr on storage life and pigmentation was investigated in homozygous material, in heterozygous F₁ combinations between the mutants with the colour mutant hp and with the normal cv. Kewalo. Crosses with nor showed a 3-to 5-fold increase in storage life in comparison with the normal cv. or with hp. Maximum pigmentation of the fruits of crosses with nor was pale-red with vineripened fruit and pink with fruit harvested at the breaker stage and ripened on the shelf. The ripening inhibitory effect of rin in the different F₁ combinations was less pronounced than that of nor, and the colour of the fruits was improved. Fruits of the F₁ cross between rin and nor showed greatly improved storage life and developed pink or pale red colour. Most heterozygotes with hp showed improved pigmentation. Problems anticipated in utilizing ripening mutants in breeding for improved keeping quality are discussed.     

Phenotypic and genomic characterization of vine cactus collection (Cactaceae)

Hylocereus (Berger) Britton et Rose, Selenicereus (Berger) Britton et Rose and Epiphyllum Haw. species have commercial potential as exotic fruit crops in semi-arid and arid lands. The high genetic variability among these species offers an opportunity for commercial cultivation. Toward this end we investigated genomic and morphological characteristics including: nuclear DNA content (2C-values), stomatal length and density, potential yield and reproductive parameters in 64 Hylocereus, Selenicereus and Epiphyllum accessions. Nuclear DNA content ranged from 3.21 pg for S. grandiflorus (L.) Britton et Rose spp. grandiflorus to 8.77 pg for H. megalanthus (Vaup.) Bauer. All species were diploid except the tetraploids H. megalanthus and S. vagans (Bgek.) Britton et Rose. Stomatal length and density, fruit weight, potential yields, number of viable seeds per fruit and fruit maturation times were highly variable among accessions. No significant correlations were found between stomatal length, density, and nuclear DNA content, nor between fruit weight and seed number. The high genetic variability found between the accessions here provides further support for the excellent prospects of conserving and domesticating these exotic species.     

荒漠区珍稀和野生果树的引种驯化

能在热带荒漠地区进行商业化栽培的作物种类是有限的,园艺作物尤其如是。本研究的目的就是通过引种驯化为热带荒漠区开发新品种。我们以下述两个来源的多年生植物为基础:干旱区和半干旱区人民食用的有营养价值的水果或干果的野生植物种;第二是从当地市场或栽培者那里能收集到的珍稀种类。以色列的内盖夫荒漠气候条件变幅宽广,水土类型多样,是本项研究的理想地点。本研究利用内盖夫的异质特点对向荒漠区引种驯化的不少植物的适宜性进行了预选试验。本文总结了从1984年开始的4年工作,并叙述了总的进展,详细介绍了六种预选植物。     

Evaluation of valuable nutrients in selected genotypes of marula (Sclerocarya birrea ssp. caffra)

Different marula clones domesticated in the arid Negev desert were evaluated for their horticultural behavior physiological and antioxidant characteristics of their fruits. Two types of abscission pattern were detected, early and late. Fruit yields fluctuated from year to year (6–45 kg/tree) with large differences between clones (few fruits to 45 kg/tree). The clones also differed in fruit weight (34.41 ± 0.91 to 56.74 ± 1.65 g), shape, and juice content. Ascorbic acid content was found to be high in all the clones with significant differences among clones and time post-abscission. Clone no 12 at 1 week post-abscission had the higher ascorbic acid content, 21.177 mg/g dry weight and clone no 4 at the abscission day had the lower ascorbic acid content, 7.142 mg ascorbic acid/g dry weight. The total antioxidant and polyphenol content of the juice varied among clones and with time post-abscission, as did the activity of superoxide dismutase (about 1.40 IU/g dry weight of SOD at week 0 for all clones, to 2.67 IU/g dry weight at the third week post-abscission). Fresh marula juice had, on average, four times more antioxidant than the juice of either orange or pomegranate (marula ascorbic acid equivalent: 8.52 ± 0.76 mM to 23.26 ± 2.20 mM versus 2.72 ± 0.39 mM to 7.38 ± 0.18 mM and 2.56 ± 0.41 mM to 3.92 ± 0.18 mM, respectively), considered to be rich in antioxidants. Marula ice cream and jam manufactured according to industrial protocols were rich in ascorbic acid 45 days post-production. In conclusion, selected genotypes of marula exhibited superior horticultural traits and high antioxidant contents. These data should be of value in selecting marula clones for commercial planting.     

Analysis of effects of auxin on fruit size of tetraploid and diploid tomato fruits

Selfed and auxin-treated fruits of tomato (Lycopersicon esculentum Mill.) were obtained from tetraploid and diploid plants and compared to determine why selfed tetraploid fruits are smaller. Application of auxin to ovaries produced tetraploid fruits as large as normally set (selfed) diploid fruits but led to reduced fruit size in diploid fruits, reflecting a further potential for tetraploid fruit development. The selfed tetraploid fruits were found to be smaller because they had fewer cells per fruit. Cell size (diameter) at the end of fruit development was similar for all fruit types. DNA per cell did not closely match cell size during development, especially during the cell division stage. Protein per cell also failed to follow cell size. Protein per DNA showed one peak at around day 10 of fruit development and possibly a second one at day 30.     

Changes in sugars,acids, and volatiles during ripening of koubo [Cereus peruvianus (L.) Miller] fruits

The columnar cactus Cereus peruvianus (L.) Miller, Cactaceae (koubo), is grown commercially in Israel. The unripe fruits are green, and the color changes to violet and then to red when the fruit is fully ripe. The content of soluble sugars was found to increase 5-fold during ripening. Glucose and fructose were the main sugars accumulated in the fruit pulp, and each increased from 0.5 to 5.5 g/100 g fresh weight during ripening. The polysaccharides content decreased during ripening from 1.4 to 0.4 g/100 g fresh weight. The titratable acidity decreased and the pH increased during ripening. The major organic acid found in the fruit was malic acid, which decreased from 0.75 g/100 g fresh weight at the mature green stage to 0.355 g/100 g fresh weight in ripe fruits. Citric, succinic, and oxalic acids were found in concentrations lower than 0.07 g/100 g fresh weight. Prominent accumulation of aroma volatiles occurred toward the end of the ripening process. The main volatile found in the ripe fruit was linalool, reaching concentrations of 1.5-3.5 microg/g fresh weight.