Comparison of Physiological Properties Between Dwarf and Vinetype Cucumbers （Cucumis sativus Linn.）

Dwarfism is one of the most important traits in crop breeding. In this study, a dwarf cucumber D0462 and a vine NA129 were taken as experimental materials. The metabolism of hydrogen peroxide （H2O2） and superoxide anion radical （O2-·, activities of antioxidant enzymes, and the levels of endogenous hormones of the two cultivars were compared. In the whole growth period, D0462 maintained higher H2O2 and O2-· levels than NA129. The activities of SOD （superoxide dismutase）, CAT （catalase）, APX （ascorbate peroxidase） and IAAO （indoleacetic acid oxidase） in D0462 were found higher than those in NA129. The contents of gibberellic acid （GA3）, indole-3-acetic acid （IAA）, zeatin riboside （ZR） and jasmonic acid （JA） in intemode were determined by enzyme-linked immunosorbent assay （ELISA）. The intemode ofD0462 remained lower levels of GA3, IAA, and ZR. In contrast, JA level in internode of D0462 was higher than that of NA129. Compared with NA129, the cell mumbers in intemode of D0462 did not change, but cell size evidently decreased. The chloroplasts in mature mesophyll D0462 exhibited swollen filled with starch grains instead of regular oval ones, and thylakoids of chloroplast swelled and became ambiguous.     

桂林市水稻主栽品种对南方水稻黑条矮缩病的抗性评价

采取田间自然诱发的方式,对桂林34个水稻主栽品种进行南方水稻黑条矮缩病抗性评价,结果表明:表现为抗病的有淦鑫203、顺优109、株两优4024、T78优2155、岳优9113、中浙优8号、中浙优1号、Y两优302、桂两优2号等14个品种;表现为感病的有陆两优28、EK优18、淦鑫206、五优308、淦鑫699、丰源优299、Q优6号、丰两优4号等20个品种;未发现免疫品种。建议农户选用上述抗性较好的品种,慎用高感品种。同时,在现阶段,"治虱防矮"仍然是防治水稻南方黑条矮缩病的最主要措施。     

醋液生物质营养液对富士苹果品质改良的作用研究

采用田间试验法,研究了醋液生物质营养液对富士苹果果实品质改良作用,以期为开发绿色环保型果树液体肥提供依据。试验结果表明:醋液生物质营养液对富士苹果叶片的光合特性和果实品质有直接影响,在适宜浓度时,分别比对照提高叶片的净光合速率253.97%;能明显增加富士苹果的着色指数、花青素含量、单果重、糖酸比、VC含量和可溶性固形物含量。由此可见,醋液生物质营养液作为苹果的品质改良剂具有很好的应用前景。     

辽西地区枣树优良品种矮化密植丰产栽培技术研究

通过用创建的枣树矮化丰产高效栽培技术,对不同品种的枣树和枣树苗的大枣产量进行调查研究,结果表明院随着栽培时间增长,枣树矮化丰产高效栽培的不同枣树和枣树苗品种产量逐年提高,较传统枣树栽培技术的产量有大幅度提高。     

核桃绿枝嫁接技术

从适期嫁接、选择适宜砧木及穗、科学操作等3个方面总结了核桃绿枝嫁接技术,以期促进当地核桃产业的发展。     

A weight‐of‐evidence approach for defining thermal sensitivity in a federally endangered species

1. Managing for threatened and endangered species under changing environmental conditions is a challenge faced by resource managers worldwide. Lack of basic knowledge of the biology and habitat requirements of these species can contribute to this difficulty but is exacerbated by the limitations of working with rare species (i.e. few individuals) or unrefined and non‐lethal methods for evaluating stress.
2. A weight‐of‐evidence approach was used to evaluate the thermal biology of the federally endangered dwarf wedgemussel (Alasmidonta heterodon), using cumulative results from multiple experimental assessments, co‐occurring species, and their host fish to begin defining the thermal limits and optimal conditions for the species.
3. Results suggest that dwarf wedgemussel and its host fish are thermally sensitive species compared with other Atlantic‐slope mussels, with a lower critical thermal maximum (CTM) and the selection of reduced temperatures during choice experiments.
4. Physiological studies resulted in a lack of statistical significance, primarily owing to low power, which was a function of sample size – an unavoidable problem when studying rare species. Given these limitations, thermal choice and CTM may be more useful end points than physiological processes such as clearance and respiration rates when dealing with sample‐size limitations.
5. These results suggest that management strategies that avoid exposing dwarf wedgemussel and its thermally sensitive host fish to extreme temperatures could be important for species conservation.

     

国内外苹果新矮化砧作中间砧对红富士树体生长结果的影响

通过对１２种国内外苹果新砧作中间砧嫁接青富１３，在树体生长、开花坐果、产量、品质、干周比值等方面进行比较，筛选出Ｍａｒｋ、７５－９－３５、Ｓ１９、７５－７－１等几种优于Ｍ２６的新矮化砧。     

Cloning and Expression of Gene Responsible for High-Tillering Dwarf Phenotype in Indica Rice Mutant gsor23

High-tillering dwarf mutant gsor23 was generated from an indica rice variety Indica9 radiatied by γ-ray. Genetic analysis showed that this phenotype was controlled by one single recessive gene, which was mapped within a physical distance of 386 kb between two insertion-deletion (InDel) markers C1-WT2 and C1-WT4 on the long arm of chromosome 1. There is a known gene D10 within this region, the mutation of which causes high-tillering in rice. Sequence analysis of the D10 allele in gsor23 revealed that the base cytosine (C) at the 404^th position in the coding region was deleted, which would cause frameshift mutation after the 134^th amino acids. The mutation site and indica background of gsor23 were different from the previously reported japonica mutants d10-1 and d10-2. Therefore, gsor23 is a novel allelic mutant of D10 which encodes the carotenoid-cleaving dioxygenase 8 (CCD8), a key enzyme involved in the biosynthesis of the new plant hormone strigolactones (SLs). After treatment with GR24, a synthetic analogue of SLs, the high-tillering phenotype of gsor23 was restored to normal. Real-time RT-PCR analysis showed that D10 expression was high in roots, but low in leaves. Compared with the wild type Indica9, the expression of the SL biosynthesis gene D10 was upregulated, while genes likely involved in the SL signal transduction pathway such as D3 and D14 were down-regulated in the gsor23 mutant.     

不同断根处理对云南拟单性木兰苗木生长影响的研究

不同断根处理对云南拟单性木兰苗木生长影响的研究结果表明:切断苗木的侧根会对苗龄为5年生的云南拟单性木兰苗木地上部分的生长产生负效应而有利于促进新侧根的萌发,其影响程度与断根的强度有关。其苗木经断根处理后新根萌发较快,50天左右有新的侧根生出,其中以切断云南拟单性木兰大苗的全部侧根于切口喷200 mg.L-1的ABT生根粉的A处理的生根效果最好。断根3个月后每株苗木萌发的新侧根平均数为138.8根,根长≥5 cm的侧根平均数为38.4根,侧根深度达32 cm,最长侧根长度14.4 cm,其苗木的新根萌发已经较为充分,可以出圃种植而能保证有高的成活率。     

桑树病毒与病毒病的研究进展(Ⅱ)

业已明确的桑树病毒病有10种。在前文报道部分桑树真病毒及病害的研究进展之后,再重点介绍桑花叶萎缩类病毒及病害的研究进展,包括病原物提取、基因组序列分析、寄主范围、致病特征、诊断方法和病害控制等,为桑花叶萎缩类病毒的深入研究以及病害的有效防治提供参考。