花粉直感对‘圆黄'梨果实品质的影响

用‘西子绿'、‘翠冠'、‘黄冠'等11个梨品种与‘圆黄'梨进行授粉试验,研究花粉直感对‘圆黄'果实品质的影响。结果表明:‘圆黄'果实在坐果率、单果重、种子数、可溶性固形物含量等方面表现明显的花粉直感现象,而在果形指数、肉质、汁液等方面表现不明显。因此,‘圆黄'梨最适宜的授粉品种是‘翠冠'、‘新酥'、‘金晶'和‘丰水'。

圆黄梨在汉水流域的引种表现及栽培技术

通过引进砂梨品种圆黄并进行栽培试验,调查分析了该品种的果品商品性、结果初期产量和适应性表现。结果表明,圆黄是适合在汉水流域发展的优良品种,黄冠、雪青可作为其授粉品种。

褐圆蚧纯黄蚜小蜂的胚胎发育和胚后发育

为深入了解褐圆蚧纯黄蚜小蜂(Aphytis holoxanthus DeBach)个体生长发育状况,采用跟踪观察,应用透射光和直射光拍摄,描述该蜂的胚胎发育和胚后发育过程。结果表明:在温度(25±1)℃、相对湿度70%±5%条件下,纯黄蚜小蜂卵期2~3 d。产卵后0~8 h为卵裂和胚盘形成阶段;16~18 h后,形成胚带和胚膜;50~52 h后,胚胎雏形形成;54 h后,胚胎形成,卵壳表面出现裂缝,卵壳从卵端部开始脱至卵柄,1~2 min完成孵化。纯黄蚜小蜂幼虫期约为7 d,蛹期7~8 d,预蛹浅黄色,老熟蛹复眼浅灰色,胸部腹板和腹部腹板大部分暗褐色。

黄褐新圆蛛对橄榄及橄榄星室木虱的影响

本文通过对黄褐新圆蛛在控制橄榄星室木虱及影响果树生长上的试验,认为该蜘蛛不是橄榄果树的有害生物,而是橄榄果树上主要害虫橄榄星室木虱的一种天敌。

3个砂梨品种在荆州地区的主要生物学特性和适应性比较

以‘长梨一号’、‘翠冠’和‘圆黄’3个砂梨品种为试验材料,调查了其芽苗在湖北荆州地区定植后第1年和第3年的生长表现和适应性,结果表明,芽苗定植后第1年,‘圆黄’株高最高,达164.4 cm,‘翠冠’株高最低,为116.4 cm;‘长梨一号’叶片数量最少,为11.5片,‘翠冠’和‘圆黄’叶片数量相当;‘长梨一号’接芽成活率最高,接芽成活率为82.4%,而‘翠冠’和‘圆黄’的接芽成活率分别为64.9%和62.1%。定植后第3年,‘圆黄’株高最高,达3.46 m,‘翠冠’和‘长梨一号’株高相当,分别为2.72 m和2.65 m;‘圆黄’冠径最大,‘翠冠’和‘长梨一号’冠径相当;从一年生枝条数量来看,‘圆黄’不论是长枝、中枝还是短枝的枝条数量均为最多,而‘翠冠’和‘长梨一号’的长枝、中枝、短枝枝条数量相当;‘圆黄’单株花序数量最多,达81簇,‘翠冠’居中,达48簇,‘长梨一号’最少,只有28簇;‘长梨一号’花序花朵数最多,达9朵,而‘圆黄’和‘翠冠’相当,只有7朵;⑤‘翠冠’和‘长梨一号’物候期相近,‘圆黄’比‘翠冠’和‘长梨一号’晚5 d左右,果实成熟期相差10 d左右;从虫害来看,‘圆黄’最轻,‘翠冠’其次,‘长梨一号’表现最为严重。由此可见,‘圆黄’梨在荆州地区的适应性最强,‘长梨一号’在荆州地区的适应性最弱。

Chemical Constituents of Hedysarum gmelinii

To study the chemical constituents of Hedysarum gmelinii. Methods Theconstituents were separated and purified by different methods of chromatography, and theirstructures were elucidated by DR, MS and NMR. Results Eight compounds were isolated from Hedysarumgmelinii, including three triteipenoids, two flavonoids and two other compounds. Their structureswere identified as squasapogenol (1), soyasapogenol (2), lupeol (3), 3, 9-dihydroxy coumestan (4),3-hydroxy-9-me-thoxy pterocarpan (5), β-sitosterol (6), palmatic acid (7), and hexadecanoic acid 2,3-dihydroxypropyl ester (8). Conclusion All the compounds have been isolated from this plant forthe first time. Compounds 1 — 4 and 8 were obtained from this genus for the first time. The NMRdata of 1 are reported for the first time.

The New Flavonoids from Polygonum sphaerostachyum(Polygonaceae)

Two novel flavone glycosides, 3′_hydroxy_5,4′_dimethoxy_6,7_methylenedioxyflavone_3_O_[β_D_xylopyranosyl(1→6)]_β_D_glucopyranoside (1) and 5,4′_dimethoxy_3′_isopropenylacetyl_6,7_methylenedioxyflavone_3_O_[β_D_xylopyranoxyl(1→6)]_β_D_glucopyranoside (2), were isolated from Polygonum sphaerostachyum Meisn., and their structures were deduced by spectral and chemical methods. This is the first report on the isolation of flavone glycosides from P. sphaerostachyum.

An Elliptical Wind Field Model of Typhoons

An elliptical wind field model of typhoons is put forward based on the characteristics of the typhoon wind fields occurring in the Yellow Sea and Bohai Sea. By contrasting it with the circular typhoon wind field model, it is found that the elliptical model can adequately represent the real wind field and trace the process of a typhoon storm surge. The numerically simulated results of storm surges by using the elliptical model are in good agreement with the observations and markedly better than those by using the circular model.

Mechanism of formation of sliding ground fissure in loess hilly areas caused by underground mining

Based on a shallow-buried coal seam covered with thick loose layers in hilly loess areas of western China,we developed a mechanical model for a mining slope with slope stability analysis, and studied the mechanism of formation and development of a sliding ground fissure by the circular sliding slice method.Moreover, we established a prediction model of a sliding fissure based on a mechanical mechanism,and verified its reliability on face 52,304, an engineering example, situated at Daliuta coal mine of Shendong mining area in western China. The results show that the stress state of a mining slope is changed by its gravity and additional stress from the shallow-buried coal seam and gully terrain. The mining slope is found to be most unstable when the ratio of the down-sliding to anti-sliding force is the maximum, causing local fractures and sliding fissures. The predicted angles for the sliding fissure of face 52,304 on both sides of the slope are found to be 64.2° and 82.4°, which are in agreement with the experimental data.

学做黄焖肉圆

星期天，写完了作业，我感觉到肚子有点饿了，就到厨房找点东西吃。刚走出我房间的门，一阵浓浓的香味从我鼻子边飘过——啊，好香啊！我顺着香味走过去，没想到真的有好吃的东西——黄焖肉圆。

日韩砂梨新品种及网架栽培技术

近几年,我们先后从日本小町园、韩国园艺研究所引入日本及韩国大量优良砂梨新品种进行种植试验,同时邀请多批日本、韩国梨树专家进行栽培技术指导,种植面积已达到20公顷.为进一步加快技术推广,现将有关品种及网架栽培技术总结如下.