番石榴番花生产应用研究

该文论述在广西职业技术学院番石榴试验园进行促夏梢、番花,成功利用番花生产番花果的试验方法、措施、关键技术等,并对番花果果实的营养成分进行测定,分析其与正造果之间的差异。试验表明番花果生产的关键技术主要有三：一是抓住时机、科学修剪和用好促发夏梢、番花肥。二是合理留好正造果;三是做好番花果保花保果、水肥管理及果实套袋等。     

Projecting the suitability of global and local habitats for myrtle rust (Austropuccinia psidii) using model consensus

Myrtle rust (caused by Austropuccinia psidii) affects more than 500 known host species in the Myrtaceae family. Three different modelling approaches (CLIMEX, MaxEnt and Multi-Model Framework) were used to project the habitat suitability for myrtle rust at both global and local scales. Current data on the global occurrence of myrtle rust were collected from online literature and expert solicitation. Long-term averages of climate data (1960–1990) were sourced from WorldClim and CliMond websites. Recent reports of myrtle rust in New Zealand were used for validation of model outputs but not in model training and testing. The model outputs were combined into a consensus model to identify localities projected to be suitable for myrtle rust according to two or three models (hotspots). In addition to the locations where the pathogen is currently present, all models successfully projected independent occurrence data in New Zealand suitable for establishment of the pathogen. Climate suitability for the pathogen was primarily related to temperature followed by rainfall in MaxEnt and the CLIMEX model. The results confirmed the optimum temperature range of this pathogen in the literature (15–25 °C). Additional analysis of the precipitation variables indicated that excessive rain (more than 2000 mm in warmest quarter of the year) combined with high temperatures (>30 °C) constrain pathogen establishment. The results of the current study can be useful for countries such as New Zealand, China, South Africa and Singapore where the pathogen has not fully spread or established.     

番石榴ISSR-PCR最适反应体系的建立与验证

为更好的将ISSR标记应用于番石榴种质研究,本研究以“维邦2号”番石榴DNA为筛选体系试验材料,采用单因子试验对ISSR反应中Mg2+浓度、dNTPs浓度、引物浓度、Taq酶浓度、DNA浓度进行了优化。实验结果表明,番石榴20µl最适反应体系为：2.0µl 10×Buffer,1.0mmol/L Mg2+,0.25mmol/L dNTPs,0.8mmol/L引物,0.2U Taq酶,10ng的DNA。利用该反应体系,选用引物UBC810对9份番石榴种质进行PCR反应,再选取“南宁本地番石榴实生2号”DNA作为模板对8条ISSR引物进行PCR反应,对所确立的扩增体系进行验证。结果显示扩增产物条带多态性丰富,且特异性强、重复性好,表明本研究所确定的反应体系适用于番石榴的ISSR分子标记。     

Puccinia psidii in Queensland,Australia: disease symptoms,distribution and impact

Puccinia psidii has long been considered a significant threat to Australian plant industries and ecosystems. In April 2010, P. psidii was detected for the first time in Australia on the central coast of New South Wales (NSW). The fungus spread rapidly along the east coast and in December 2010 was found in Queensland (Qld) followed by Victoria a year later. Puccinia psidii was initially restricted to the southeastern part of Qld but spread as far north as Mossman. In Qld, 48 species of Myrtaceae are considered highly or extremely susceptible to the disease. The impact of P. psidii on individual trees and shrubs has ranged from minor leaf spots, foliage, stem and branch dieback to reduced fecundity. Tree death, as a result of repeated infection, has been recorded for Rhodomyrtus psidioides. Rust infection has also been recorded on flower buds, flowers and fruits of 28 host species. Morphological and molecular characteristics were used to confirm the identification of P. psidii from a range of Myrtaceae in Qld and compared with isolates from NSW and overseas. A reconstructed phylogeny based on the LSU and SSU regions of rDNA did not resolve the familial placement of P. psidii, but indicated that it does not belong to the Pucciniaceae. Uredo rangelii was found to be con‐specific with all isolates of P. psidii in morphology, ITS and LSU sequence data, and host range.     

番石榴SRAP反应体系的建立与正交优化

采用正交设计方法,对影响番石榴SRAP反应体系的Mg2+、dNTPs、引物、Taq DNA聚合酶和模板DNA浓度等进行了优化,建立了适用于番石榴的SRAP反应体系。该优化的20 μL反应体系中包含2.5 mmol/L Mg2+,0.15 mmol/L dNTPs,0.4 μmol/L引物,1.5 U Taq DNA聚合酶和20 ng模板DNA。利用该优化体系通过64对SRAP引物组合对5份番石榴材料进行了SRAP-PCR扩增,结果表明SRAP引物及优化后的反应体系能够有效地用于番石榴种质资源鉴定及遗传多样性分析等研究。     

Mineral Composition and Soil-Plant Relationships for Common Guava (Psidium guajava L.) and Yellow Strawberry Guava (Psidium cattleianum var. lucidum) Tree Parts and Fruits

The mineral compositions of the fruit and tree parts of common guava, Psidium guajava L., and strawberry guava, Psidium cattleianum var. lucidum, were determined. The study occurred during three seasons at six locations in Hawaii to assess guava as feed for livestock. Guava bark contained the greatest concentrations of calcium (Ca) and ash; leaves the greatest concentrations of magnesium (Mg), sulfur (S), sodium (Na), boron (B), and manganese (Mn); and the shoots had the greatest concentrations of nitrogen (N), phosphorus (P), and potassium (K). The leaves and the shoots had the greatest concentrations of copper (Cu) and iron (Fe). Between guava and waiwi, guava had greater concentrations of most minerals except for Na in all plant parts, and Mg and ash in the leaves. Guava leaves and shoots meet the macromineral requirements for various phases of sheep, goat, and beef cattle life cycles with the exception of P and Na. Guava shoots do not meet Mn requirements for lactating cows.     

金沙江干热河谷台湾珍珠番石榴引种试种初报

台湾珍珠番石榴经在元谋金沙江干热河谷引种试验,表现速生、早结、丰产、抗逆性强,果大质优,供果期长,适应性强。     

番石榴叶精油的提取、成分鉴定及对红火蚁的生物活性分析

为评价番石榴叶精油(EO)对红火蚁的熏蒸活性,采用熏蒸法和气相色谱-质谱联用(GC-MS)等技术测定精油对红火蚁的生物活性。EO含有31种化合物,caryophyllene(37.86%)为主要化合物。生测结果表明,20 µL/管的EO熏蒸红火蚁48 h,死亡率达90%以上;熏蒸红火蚁9 h,聚集率下降了78%,攀爬率下降了45%,抓附率下降了34%,行走率下降了30%。10 µL/管的EO熏蒸红火蚁48 h,体内过氧化氢酶(CAT)和羧酸酯酶(CarE)酶活力分别降低了56.62%和58.57%,红火蚁毒腺分泌哌啶化合物的组分降低了50%。番石榴叶精油对红火蚁具备良好的熏蒸活性,并抑制其行为能力、体内酶活力及生物碱的分泌。本研究可为番石榴的深度开发及红火蚁的生物防控提供理论依据。     

一种新的提高树苗盐容量的移植方法

The influence of quinclorac (3,7-dichloroquinoline-8-carboxylic acid) on enzyme activities in flooded paddy soils was assessed under laboratory conditions. The enzymes differed markedly in their response to quinclorac. Quinclorac inhibited proteinase, hydrogen peroxidase, phosphorylase, and urease activities. The higher the concentration of quinclorac applied, the more significant the inhibition to these observed activities with a longer time required to recover to the level of the control. However, soils supplemented with quinclorac were nonpersistent for proteinase~ phosphorylase and urease as opposed to soils without quinclorac. Dehydrogenase activity was also sensitive to quinclorac. Three soil samples with concentrations of quinclorac higher than 1 μg g^-1 soil declined to less than 20% of that in the control. However, the highest dehydrogenase activity (up to 3.28-fold) was detected in soils with 2 μg g^-1 soil quinclorac on the 25th day after treatment. Quinclorac had a relatively mild effect on saccharase activity at the concentrations used in this experiment and a stimulatory one on soil respiration when added to soil at normal field concentrations. Nonetheless it was inhibited at higher concentrations in paddy soils. Quinclorac is still relatively safe to the soil ecosystem when applied at a normal concentration (0.67 μg g^-1 dried soil) but may have some effects on soil enzymes at higher concentrations.     

福建番石榴上的一种新病害—棒盘孢枝枯病

本文首次报道番石榴棒盘孢枝枯病在福建连江的发生及为害情况,并描述了该病的症状及其病原菌(Coryneum psidii Sutton)形态。