Abstract:研究了由~(60)Co-γ辐照诱导的水稻抗白叶枯病突变体培育而成的辐竹_2及辐竹_2选两个品种的遗传方式,证明该两个品种的抗性遗传受多基因控制。根据超亲遗传现象,判明供试抗源的基因分布为非集中分布型。对辐照突变体筛选的有关问题及突变体的利用途径开展了讨论。并对这类多基因遗传的突变体在抗病育种中的利用价值作出较为肯定的评价。

Abstract:A mathematical model of the preying of four species of spiders, Oodothorax in-secticeps, Pirata subpiraticus, Clubiona japonicola and Bianar hotingchlechi on the white-backed rice planthopper Sogatella furcifera was studied with quadratic regression rotation composite design and reported in the paper. The mathematical model of the preying of the predators on the white-backed planthopper was asfollows:Y = 13.1492 + 0.4583x1 -0.125x2 + 0.625x3 + 1.0417x4 + 13.9583x5-0.9375x1x2 + 0.4375x1x3 -0.0625x1x4 +2.25x1x5 + 0.1875x2x3 + 0.1875x2x4 - 0.3125x2x5 - 0.6875x3x4 + 0.5625x3x5 + 0.0625x4x6 + 0.1008x12 - 0.2742x22 + 1.2258x32 + 0.1008x42 + 4.4758x52Furthermore, the response surfaces of interaction between two species of spiders were also studied. It proved that there were interference between species and detween individuals of the same species of the four predators.

Abstract:The present paper is a partial revision of Chinese Apocynaceae based on the latest information cnotained in Chinese and foreign literature. It included 17 genera, 32 species and one variety, involving seven new combinations and one new distribution: Micrechites borneensis; M. gracilis; Pottsia laxiflora var. pubescent; Ecdysanthera xylinabariopsoides; E. huaitingii;E. tournieri and E. linocarpa. Also, forty-six taxon names were newly removed:Carissa yunnanensis = C. spinarum; Amsonia sinensis = A. elliptica; Kopsia offjcinalis = K. lancibracteolata; Rauvolfia taiwanensis, included R. brevistyla, R. yunnanensis, R. latifrons, R. verticillata var. oblanceolata and var. officinalis, var. hainanensis = R. verticillata; Alyxia yunkuniaia = A, sianensis;A. nitens, included A. lehtungensis, A.euonymifolia, A. jasminea, A. vulgaris=A. hainanensis; A. funingensis = A. marginata; A. acutifolia, included A, kweichowensis = A. levinei; Parsonsia howii = A. alboflavescens;Alstonia guangxiensis = A. neriifolia; Anodendron fanchengense, included A. salicifolium. A. affine var. effusum and var. pingpinense= A. affine; Aganosma schlechteriana var. leptantha = A. schlechteriana; Aganosma kwangsiensis= A, siamensis;A. montana = A. navaillei; Micrechites malipoensis var. parvifolia= M. malipoensis; Trachelospermum siamense. included T. lanyuense and T. gracilipes var. hupehense=T.gracilipes; T.eglandulatum and T. tenax = T. dunnii;T. cathayanum var. tetanocarpum included T.yunnanense and T. formosanum = T. bodinieri;Ichnocarpus frutescens f. pubescens = T. frutescens; Chunechites and Parabarium = Ecdysanthera. and one new distribution: Alyxia fascicularis. All the types are kept in SCBI. PE, KUN and SCAC.

Abstract:In this paper we report the effects of sodium chloride on the activity of glycolate oxidase in wheat seedlings. At 20 hrs after spraying sodium chloride on wheat seedlings, the activity of glycolate oxidase increased by 21% and the content of Protein increased by 24.2%.After the seedlings had been cultivated with 0.1, 0.2, 0.5 mol/L of sodium chloride, the glycolate oxidase activity increased by 23.0, 61.1, and 28.6 percent respectively over the control| the contents of proteinincreased by 12.8, 29.4, and 18.1 percent respectively over the control, but the chlorophyll content decreased by 2.8, 2.8, and 22.2 percent respectively. The mechanism of increase of glycolate oxidase was discussed.

Abstract:Observation was done on the sperm from the testis of the Sugarcane Yellow Stem Borer, Tetramorea schistaceana (Lepidoptera, Olethreutidae). Emphasis was given to the comparison of the ultrastructure of the eupyrene and apyrene, and the effects of y-radiation on the ultrastructure of the sperm in P and F1 progeny of irradiated males.The results showed the number of sperms in most of the sperm bundles was 23, while in some of the apyrene bundles the number was 29. Both the eupyrene and apyrene had an axoneme with a configuration of 9 + 9 + 2 and a couple of mitochondria derivatives, which were more closely associated and uneven in size in the eupyrene while in the apyrene they were separated and similar in size. However, the most obvious difference was that the apyrene lacked elaborate lacinate appendages and reticular appendages, which extended from the plasma membrane of the eupyrene testicular spermatozoa.Irradiation of late pupae at a dosage of 30 KRad resulted in a few flagellar abnormalities in eupyrene sperms and several large bodies with high electron density mixed with the apyrenes in the sperm bundles. Irradiation of p late pupae at a dosage of 15 KRad resulted in a higher frequency of flagellar abnormalities in eupyrene sperms and irregular arrangement and degeneration of sperms in apyrene bundles of testis of F1 males produced from crossing irradiated P males with the untreated females. However, most of the sperms and sperm bundles found in either the treated P males or Fi males were mormal.

Abstract:The ultrastructural changes occurring during microgametogony in Tyzzerio parvula were studied in tissue from the small intestine of infected young domestic geese. The development of the trophozoite into the microgametocyte was accompanied by cytoplasmic growth and nuclear division. The developing microgametocyte could be differentiated from developing schizont because the nuclei of the microgametocyte were smaller than those of the schizont and lacked nucleoli. Every nucleus migrated to the edge of the microgametocyte accompanied by the aggregating of chromatin at the periphery of the nuclei. Then each nucleus became elongated, protruding outwards from the microgametocytic membrane, and developed a dense osmiophilic area which contained the condensed chromatin, and a pale area. The dense portion of the nucleus, accompanied by the mitochondrion, entered the protrusion to become the nucleus of the microgamete, and the pale portion remained in the residual body. The two centrioles above the ucleus transformed into the basal bodies from which the flagella arose. The microgamete consisted of two flagella, an elongated nucleus, a mitochondrion located at the anterior end, and microtubules alongsaide.

Abstract:This paper reports experiments with extracts from flowers of the yellow azelea (Rhododendron molle) on several agricultural insect pests. It was found that the crude extracts of R. molle possessed high antifeedant and stomach poison activities against several species of agricultural insects. Dichloromethane extracts (FCb) from the flowers of R. molle showed high toxicity against the third instar larvae of the diamond-back moth (Plutella xylostella). A strain of the moth highly resistant to fenvalerate showed no resistance to the fraction FCb. the LC50 of the resistant and sensitive diamond-back moth populations to FCb was 0.33% end 0.37% respectively. The insects showed symptoms of excitment, spasm and vomiting quickly after eating the extracts of R. molle, but they were killed slowly. Among the extractions of R. molle, the fraction FC-22 was found to be the most potent. The fifth instar larvae of the oriental army worm (Mythimna separata) showed more than 90% inhibition of feeding when treated with 150 ppm of FC-22. The respiration of the fifth instar larvae of M. separata was markedly depressed after eating a small amount of the extract FC-22. Increased multifunction oxida-se (MFO) activity was induced by the extract FC-22. The results of our experiments also showed that the extracts of R. molle had a strong oviposition deterrent effect on the females of pieris rapae under green-house conditions. Results of potted trials demonstrated that cabbages were protected from the damage of the larvae of P. rapae by spraying with 0.5% of extracts from flowers of R. molle. Since R. molle showed efficacy in the control of agriculral insects, it seems to be promising as a botanical insecticide for use in integrated pest management programs of vegetable insects in China.

Abstract:Based on the description of 4 shape-parameters of statistical distribution indices of aggregation and the regression analysis of population spatial pattern, the spatial pattren dynamics of aphid populations was elucidated to be as follows: 1 . In the whole season the spatial distributions were of the contagious type with positive skewness and steeper pesk than normal distribution. 2 .the Fuzzy cluster aggregation states may be classified as types of early, middle and late stage in fall crop and types of early and late stage in spring crop with different densities and aggregations. 3. The method of sampling, wether random or sequential, and methods of transformation of raw data could conveniently be determined and realized with the aid of parameters obtained in the Taylor's power law or two M*=M regressions.

Abstract:For working out the relation between the ecological property and cultivation technique of Leucaena leucocephala cv Salvador, the growth and behaviour of several seedlings were studied with different treatments in acid soils. The studies reported in this paper on the seedlings showed that with calcium superphospate applicaion relatively high biomass could be gained even though no lime or urea was provided. Moderate liming improved growth markedly. A little urea promoted growth when accompanied by P application. Urea repressed germination.

Abstract:Air-dried rice seeds were irradiated with 400Mev/amu accelerated argon ion beam. The genetic effects of M2 quantitative characters were studied.The results showedthat the heritability (hb2 )of all studied characters changed with different absorbeddoses. The heritability (hb2 ) and G.C.V.of all studied traits were rather highin the M2 generation rice seeds treated with 40Ar ion beam in the dose range of 60-120Gy. The relative genetic advance of each trait varied greatly with various dose treatments. Every trait could gain considerable genetic advance within the range of its appropriate absorbed doses.

Abstract:The temporal and Spatial dynamics of the aphid vectors (Myzzus persicae and Rhopalasiphum pseudobrassicae) of the Chinese-small-cabbage mosaic disease were outlined by means of fuzzy cluster analysis. At the early stage of the epidemic aphids mainly of alatae immigrating from the outside of the field were of low density and poisson distribution, but sometimes low aggregations were observed. After the colonization of the aphids in the field, the infestation increased greatly in a short time, but soon the rate of infestation began to decrease; the density of aphids, however, still continued to increase, resulting in a high aggregation in the season. When the aphid-infested plants reached 90%, the rate of infestation was greatly slow down; the aggregation became lower than before, being stable. The size of the aphid population continued to increase to a peak just before harvest of the crop.The dynamic of disease progress was also studied with a Fuzzy cluster analysis. At the early stage of the epidemic the inoculum (virus) was carried and spread by the immigrating alatae with a random distribution, which resulted in a random distribution of diseased plants in the field. Due to the rapid spatial spread of the disease, there was a rapid increase in number of diseased sampling units, which was paralleled by an increase in percentage of diseased plants in the field. However, at the beginning there was often only 1 diseased plant per sampling unit. Owing to the immigration and colonization of the vectors, inter-and intra-unit spread of disease occurred simultaneously and was accompanied with an increase of disease severity. The migration of vectors in the field facilitate the spread of diseased plants all over the field, resulting in a rapid increase of diseased sampling units to 100% and diseased plants as well. At the last stage of the epidemic, nearly all plants were infected and thus the disease progress was then reflected in the iacresease of severity.