Evaluation of resistance to sharka (Plum pox virus) of several Prunus rootstocks

Sharka (Plum pox virus, PPV) severely affects the production of most Prunus species in the areas affected by the disease. In this study, the resistance of 15 Prunus rootstocks to a Dideron type isolate of PPV was evaluated under controlled conditions in an insect‐proof greenhouse. After four cycles of study,‘GF677’ almond x peach hybrid,‘Myrobolan 29C plum and ‘L2’ cherry did not show any symptoms and were ELISA‐DASI and RT‐PCR negative. These were considered resistant to PPV. The rest of the rootstocks assayed showed symptoms of sharka (confirmed by ELISA‐DASI or RT‐PCR), although the level of susceptibility was different for each rootstock.‘GF305’ peach, ‘Puebla de Soto’ plum and ‘Real Fino’ apricot, were highly susceptible to PPV, showing strong sharka symptoms and being ELISA and RT‐PCR positive. ‘Marianna 2624’ plum,‘AC 9921‐07’ hybrid and ‘CP‐2’ plum showed susceptibility to PPV confirmed by ELISA‐DASI and RT‐PCR positives.‘Nemaguard’ and ‘Nemared’ hybrids, ‘Torinel’ plum and ‘STN2’ hybrid showed an intermediate susceptibility to PPV with slight sharka symptoms and were ELISA‐DASI and RT‐PCR positive. Whereas, ‘Montclar’ peach and ‘Evrica’ hybrid showed moderate resistance to PPV with slight sharka symptoms and were ELISA positive but RT‐PCR negative. The results open new possibilities in the search for different sources of resistance to PPV within Prunus.     

苦瓜皂甙降血糖功能的研究概况

苦瓜果实富含皂甙、多肽和活性蛋白等多种功效成分,现代药理研究证明,苦瓜皂甙具有降血糖、降血脂、抗癌、抗艾滋病、抑菌、抗氧化和增强免疫等功效。通过对苦瓜皂甙的开发,不仅为苦瓜产品的开发提供新的途径,也为人们的合理膳食提供素材。     

矮化中间砧红星苹果树各器官营养元素含量变化研究

研究表明,红星苹果树在年周期内各器官营养元素的含量变动很大,不同砧穗组合也有一定差异.矮化中间砧树叶片、果实和发育枝内多数营养元素含量高于乔砧树.红星苹果产量与叶内氮、磷的含量呈正相关,而与叶内钾的含量呈负相关.文中还讨论了营养元素在器官间存在的相关性.     

棉花黄萎病抗性鉴定新方法——无底塑钵菌液浇根法

通过一系列的试验 ,笔者发展了一种快速鉴定棉花品种抗黄萎病性能的新方法—无底塑钵菌液浇根法 ,此法比传统的纸钵撕底醺根法更简便 ,发病较轻 ,能准确客观地反映品种的抗性     

Genetic control of irregular striping, a new phenotype in Cucurbita pepo

Longitudinal striping of the fruit exterioris a common trait in Cucurbita pepo(pumpkin, squash, gourd). Striping occursas ten pairs of alternating dark and lightstripes that are regularly situated inaccordance with the ten sub-epidermalcarpellary vein tracts. Usually, the darkstripes occur in the central areas betweenthe vein tracts, with the light stripesoccupying the remainder of the fruitsurface. A new phenotype is described inwhich dark spots or streaks occur in thecentral areas between the vein tracts;these are usually accompanied by darkstreaks or stripes that occur adjacent toand over part or all of the length of someor all of the ten carpellary vein tracts. The inheritance of this irregular stripingpattern was studied by crossing anaccession that bred true for this phenotypewith a near-isogenic line havinglight-colored fruits. The resultsindicated that irregular striping isdominant to light coloration and isconferred by a single gene. Testcrossesfor allelism with regular striping wereprepared by crossing the irregularlystriped accession with near-isogenic lineshaving broad stripes, l-1 ^BSt/l-1 ^BSt, and narrowstripes, l-1 ^St/l-1 ^St. The testcross results revealed thatirregular striping is conferred by anallele at the l-1 locus, designatedl-1 ^iSt. The l-1 ^iStallele is dominant to light-colored (l-1), recessive to dark-colored (L-1), and can be co-dominant or recessiveto broad-striped (l-1 ^BSt) andnarrow-striped (l-1 ^St),depending on whether or not it is fullyexpressed. Dominance relationships at thel-1 locus can, therefore, berepresented as L-1 > (l-1 ^BSt > l-1 ^St) l-1 ^iSt > l-1.     

丝瓜伤流液对采后榆黄蘑呼吸及贮藏品质的影响研究

试验研究丝瓜伤流液对榆黄蘑的保鲜效果结果表明 ,用丝瓜伤流液作保鲜剂明显抑制榆黄蘑呼吸分解代谢 ,有效减缓菌盖开裂、褐变和失水。且有棱丝瓜伤流液保鲜效果优于无棱丝瓜伤流液 ,以 75 %有棱丝瓜伤流液保鲜效果最佳     

Silicon nutrition of tomato and bitter gourd with special emphasis on silicon distribution in root fractions

Two plant species, tomato (Lycopersicon esculentum Mill.) and bitter gourd (Momordica charantia), were used for in‐depth studies on the dynamics of silicon (Si) uptake and translocation to the shoots and compartmentation of Si in the roots. The experiments were conducted under controlled environmental conditions in nutrient solutions, which were partly amended with 1 mM Si in the form of silicic acid. At harvest, xylem exudates were collected, and Si concentrations and biomass of roots and shoots were determined. Mass flow of Si was calculated based on the Si concentration of the nutrient solution and transpiration determined in a parallel experiment. Plant roots were subjected to a fractionated Si analysis, allowing attributing Si to different root compartments. Silicon concentrations in the roots compared to the shoots were higher in tomato but lower in bitter gourd. A more ready translocation from the roots to the shoots in bitter gourd was in agreement with Si concentrations in the xylem exudates which were higher than in the external solution. In tomato, the xylem‐sap Si concentration was lower than in the nutrient solution. Calculated Si mass flow to the root exceeded Si uptake in tomato, which was consistent with the measured accumulation of Si in the root water‐free space (WFS). In contrast, Si concentration in the root WFS was lower than in the nutrient solution in bitter gourd, reflecting the calculated Si depletion at the root surface based on the comparison of Si mass flow and Si uptake. Within the roots, more than 80% of the total Si was located in the cell wall and less than 10% in the cytoplasmic fractions in tomato. In bitter gourd, between 60% and 70% of the total root Si was attributed to the cell‐wall fraction whereas the proportion of the cytoplasmic fraction reached more than 30%. Our results clearly confirm that tomato belongs to the Si excluders and bitter gourd to the Si‐accumulator plant species for which high Si concentrations in the cytoplasmic root fraction appear to be characteristic.     

西瓜和甜瓜的SSR引物对三种瓜类作物的通用性分析

利用西瓜的1 824对SSR引物和甜瓜的259对SSR引物,对丝瓜、冬瓜和苦瓜的DNA进行了PCR扩增,分析了西瓜和甜瓜SSR引物对三种瓜类作物扩增的通用性以及三种瓜类作物中不同类型之间的多态性.结果表明,西瓜和甜瓜SSR引物对丝瓜、冬瓜和苦瓜的DNA扩增通用性分别是15.31％、23.04％和14.74％.但是,在三...     

早熟苦瓜新品种“赣优1号”、“赣优2号”的选育

赣优1号、赣优2号是分别以强雌系Q11-2、Q9-4为母本配制成的早熟杂交苦瓜新品种。赣优1号商品果绿白色,棒形,果长35cm,横径6cm,肉厚1.0cm,单果重400g,特早熟,春季栽培从定植至初收40d,每公顷产量37500kg。赣优2号商品果绿色,棒形,果长30cm,横径7cm,肉厚1.2cm,单果重500g,早熟,春、秋季均可栽培,春植从定植至初收45d,秋植从播种至初收45d,每公顷产量45000kg。     

扁桃砧木Nemaguard和Lovell的组培快繁

试验对扁桃砧木 Nemaguard 和 Lovell 进 行 组培快繁 ,结果表明: Nemaguard 以 MS+6-BA0.5 mg/L+GA30.2 mg/L 为最佳诱导培养基,Lovell 则以 MS+6-BA2.0 mg/L+GA0.2 mg/L 为最佳诱导培养基,其诱导成活率分别为 73.3 %和 80.0 %。Nemaguard 适宜的增殖培养基为 MS+6-BA1.0mg/L+GA30.1 mg/L+LH100 mg/L,而Lovell 则为 MS+6-BA1.0 mg/L+IAA0.1 mg/L+LH 100 mg/L。经过一月的培养,其增殖倍数为 3.05 和 5.23,茎长大于1 cm的新梢率为57.0 %和55.9 %。生根诱导则以1/2 MS+IBA 0.5 mg/L配合10 d暗培养效果最好,Nemaguard 和 Lovell的生根率可达 80 %和 66.7 %。移栽成活率能达到 70 %以上。