Abstract:Nine crosses were studied from 1980 to 1984.The main results are shown as following:1.Short culm plants with early maturity,which have some donor traits could be selected in the BC2 generation.2.The main economic traits of the recurrent parent could be basically recovered in BCz or BC1F1(BC2F1)generations.3.Selection effects for traits in backcrossed generations depends upon the rate of homozygosity advance which should show the same trend as narrow heritability and gene effects for traits.4.The net increment of homozygosity proportion in BC2 fitted in with the theoretical results calculated by formula and thus the number of genescontrolling the traits could be calculated.The proportion homozygosity of some traits in BC1F1 are about 1/2-1/3 of BC1 progenies.5.High heritability traits such as grain number per panicle and weight per thousand grains can be improved synchronously by limited backcrossing in breeding procedures.Based on strict selection of recurrent parents,new varieties which maintain(or surpass)the main desirable traits of the original varieties and have short or semishort culm,early maturity and big panicles can be selected by limited backcrossing in a shorter breeding period.The results showed that limited backcrossing can shorten the breeding period and is an effective technique.

Abstract:本文研究肉猪饲以营养水准价值高的饲粮时,猪生长激素(PST)对猪生长后期的影响。选用杜洛克×长白×约克夏三元杂交猪,长白×本地大花白×长白杂交猪(即长白级进二代)及长白×本地大花白杂交猪共240头进行试验,每天每头试验猪颈部肌肉注射PST 2、4或6 mg,连续给药70天。停药7天后进行屠宰,测定的参数是净增重、料肉比和胴体品质性状等。所得数据用方差分析方法进行生统处理,本试验的研究结果表明,PST能显著增加三种杂交猪的瘦肉率、瘦肉肥肉比与眼肌面积,使膘厚变薄、料肉比减小,在养猪业中具有应用价值。

Abstract:This is the first report on ultrasonotomography of a megacholecyst in the water buffalo.The area of the megacholecyst sonogram reached 159cm2 and the perimeter 686mm.Its size was six times larger than that of normal cholecysts of buffaloes.The sonogram of the megacholecyst was described and measured,and compared with cholecyst sonograms of 11 buffaloes and 18 cattle.The size of cholecysts in one hundred live cattle undergoing surgical operation and that of 50 fresh specimens obtained from the market were also compared with that of the sonogram of this megacholecyst.

Abstract:This is a report on the first trial of neem(.Azadirachta indica A.Juss)introduction and cultivation in China.The results show that the neem trees could be planted successfully in Wanning County of Hainan Province which is a tropical region.The neem seeds were collected from Lom'e,Togo,Africa.The seedlings grew very well in the nursery in Hainan.After three months the seedlings grew up to 40-50 cm high,then they were transplanted to the forest area.The neemtrees grew very fast after transplantation,Their canopy was formed in two years,when they grew to as high as 6.0 m.with a trunk diameter of 9.76 cm.The first flowerbuds appeared and bloomed when the trees were two years old,but the neem fruits matured four monthes later.The mature seeds collected from the trees could germinate and the second generation have also been cultivated successfully.The neem trees also exhibit the capabilities of wind-resistance,drought-tolerance and cold resistance during the two years of cultivation in this place.

Abstract:This paper mainly describes two new genera of the Dendrocalameae and provides a schematic presentation of the evolutionary path of the Tribe Dendrocalameae from China.Sellulocalamus and Patellocalamus are two new genera which were discovered in S.W.China;they do not belong to the Genus Dendrocalamus as previously thought because they originated from different species of the Genus Bambusa.

Abstract:With the data obtained from inoculation experiments,the apparition dynamic of asparagus long bean(Vigna sesqurpedalis(L.)Fruvvirth)rust(Uromyces phoseoli Wint var.Vignae(Barcl.)Arth)was studied in detail,showing that Richards function was the best for the description of the apparition dynamic and there was no singificant difference between Logistic and Gompertz functions.As a unit,the effective accumulated temperature was found to be better than day for the study of the probability of apparition of this fungus no matter which function was used.The method for determining the latent period of the disease by the use of inflexion of the function was described,the latent period of the disease studied being found to be 7-9 days.

Abstract:本文研究了芥兰(Brassica alboglabra Bailey)花芽形态发育,不同播期和春化条件对芥兰不同品种花芽分化的影响。 芥兰的花芽形态发育可分为6期:1.花芽未分化期,2.花芽将分化期,3.花芽分化始期;4.萼片分化期;5.雌雄蕊分化和形成期,6.花瓣分化发育期。花器官的分化顺序是萼片、雌雄蕊、然后是花瓣。 早、中、迟熟品种同时播种表明,早芥兰的花芽分化期最早,分化叶位最低,迟芥兰的花芽分化期最迟,分化叶位最高,中芥兰则介于两者之间。 芥兰(中迟芥兰品种)在广州7～12月分期播种,以9～10月播种的花芽分化期最早,7～8月播种的较迟,11～12月播种的最迟。随着播种期的延迟,花芽分化时的展叶数逐渐减少,分化叶位逐渐降低。 3±1℃和8±1℃春化处理7、14和21天,对早芥兰的花芽分化期和分化叶位没有明显影响,中迟芥兰则不同程度地提早花芽分化和降低分化叶位。

Abstract:Miaoer mountain,the altitude of which is 2142 meters,is covered with dense vegetation due to abundant annual rainfall.The soils in that mountain developed mainly from granite and partly from arenaceous shale,phyllite and slate in some areas.The genetic process of soil in Miaoer mountain gets weaker with increase in altitude.The vertical sequence of soils from the mountain foot to the summit is in the order of mountain red earth,mountain yellow earth,mountain yellow-brown earth and mountain shrubby meadow soil.Corresponding to the vertical sequence ofthe soils,the quantity of 2:1 type mineral increases and that of kaolinite decreases gradually.Halloysite and gibbsite exist in all soil profiles and the latter tends to increase with the increase of depth.14A intergradient mineral is found mainly in the soils at about a little below the middle of the mountain where a mixed layer of mineral commonly occurs.The weathering index of the primary mineral in the soil developed from granite gets less with the increase in altitude.The conditions for the transformation of gibbsite are dealt with in this paper,and the relation among soil allitization,soil weathering and red earthening is also presented.

Abstract:The significance of barriers lies not only in theia being protective structures,but also in their importance in maintaining constant micro-environments for organs in the which barriers are located.This article describes the structure and main functions of 12 kinds of barriers in the animal body.