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1.
本文通过亲虾越冬大规模人工育苗的生产性试验,总结了适用于生产的育苗技术措施:通过分类管理可以适时并相对集中地获卵;为提高育苗的成活率,采取低温产卵、适温孵化、上限育苗”的控温技术。赵冬亲虾可以多次产卵。 相似文献
2.
灭幼脲毒理学研究——Ⅳ.灭幼脲的激素效应模拟试验 总被引:1,自引:0,他引:1
以灭幼脲(Diflubenzuron,DFB)极高剂量(死亡剂量)处理6龄粘虫幼虫,对少数存活且外观健壮的试虫作组织学观察,发现对激素分泌器官咽侧体(CA)及前胸腺(PG)以及激素作用靶器官脂肪体(FB)都表现刺激效应。保幼激素(JH)类似物ZR-515,蜕皮激素(MH)和DFB单用或混用,以脂肪体合成蛋白质能力的高低作为比较指标,发现DFB和ZR-515有类似效应;MH则可促进蛋白质合成或吸收能力,但和DFB合用后,其能力下降。由此表明,DFB可能系通过类似JH效应,从而增加体内JH影响,引起内源性激素平衡失调作为其毒杀机制的重要方面。 相似文献
3.
采用双测交育种方法,育成了强健优质春用蚕品种贵蚕二号(827·渝5×826·渝3),系四元杂交种。经多次鉴定、农村饲养、试繁结果表明:该品种体质强健好养,制种性能好,茧大而匀,茧丝质良好,综合经济性状优良,四龄万蚕收茧量23.03kg,四龄万蚕茧层量5.86kg,茧成率25.43%,茧丝长1446m,解舒丝长1253m,鲜毛茧出丝率19.93%,净度96.88分。适宜贵州省春季用种. 相似文献
4.
5.
全纯人工营养液饲养蚜虫的研究 总被引:6,自引:1,他引:6
根据蚜虫高度特化的取食习性和平衡营养的需求,本文报道了一种较为理想的全纯营养液配方(由氨基酸、维生素、糖、盐类及微量元素等构成)和优化的人工饲养蚜虫技术体系。这为进一步深入研究蚜虫生理代谢、测定杀虫剂效果和探讨作物抗蚜生理生化机理等奠定了实验技术基础。 相似文献
6.
The transition time from the juvenile phase to the adult phase differs in soybean cultivars ‘Enrei’ and ‘Peking’ 下载免费PDF全文
Suguru Ozawa Katsunori Hatakeyama Yoshihito Takahata Shuji Yokoi 《Plant Breeding》2017,136(3):386-392
Plants develop juvenile phase to adult phase in vegetative stage. Although soybean is a very important crop worldwide, there has been only one study of the juvenile–adult phase change. In this study, we determined that the juvenile–adult phase change occurred at different stages in two soybean cultivars that differ in their photosensitivity. Cultivar ‘Enrei’ (E1e2e3E4) is weakly photosensitive and cultivar ‘Peking’ (E1E2E3E4) is strongly photosensitive. In ‘Enrei’, the leaf size gradually increased at a constant leaf position regardless of the difference in day length. In ‘Peking’ plants transferred to short‐day conditions at several leaf development stages, leaf size gradually increased at different leaf positions. Expression of miR156 by ‘Enrei’ transferred to short‐day conditions had nearly the same pattern as that of ‘Enrei’ grown under long‐day conditions. In ‘Peking’, the expression of miR156 had different patterns in younger leaves of plants subjected to either a short‐day treatment or long‐day conditions. These results indicate that the E2 and E3 loci that regulate photosensitivity also regulate the expression of miR156 and the juvenile–adult phase change in soybean. 相似文献
7.
Cold tolerance during juvenile development in sorghum: a comparative analysis by genomewide association and linkage mapping 下载免费PDF全文
Karin Fiedler Wubishet A. Bekele Claudia Matschegewski Rod Snowdon Silke Wieckhorst Arndt Zacharias Ralf Uptmoor 《Plant Breeding》2016,135(5):598-606
Improved cold tolerance during the juvenile phase is a major breeding goal to develop new sorghum cultivars suitable as an alternative energy crop in temperate regions. The objectives of this study were to identify marker‐trait associations for cold tolerance in a sorghum diversity panel fingerprinted with 2620 single nucleotide polymorphism (SNP) markers and to detect quantitative trait loci (QTL) in two F2:3 populations. Traits of interest were dry matter growth rate (DMGR), leaf appearance rate (LAR), chlorophyll content (SPAD) and chlorophyll fluorescence (Fv′/Fm′ and ФPSII) in relation to temperature. The association panel comprised 194 genotypes, while the F2:3 populations consisted of 80 and 92 genotypes. All populations were tested under controlled conditions in a minimum of four temperature regimes ranging from 9.4°C to 20.8°C. QTL were identified for means across environments and regression parameters describing temperature effects. Several marker‐trait associations for mean (m) DMGR, base temperature (Tb) of SPAD and ФPSII and temperature effect on LAR were validated by QTL detected in population 1 or 2. Promising QTL regions were found on chromosomes SBI‐01, SBI‐02, SBI‐03, SBI‐04, SBI‐06 and SBI‐09, among them genomic regions where candidate genes involved in the C‐repeat binding pathway or encoding cold‐shock proteins are located. 相似文献
8.
Marek Jindra 《Journal of Pesticide Science》2021,46(1):3
Insect Growth Regulators (IGRs) represent advanced, bio-rational insecticides. This Special Issue reflects progress in IGR development that has been enabled by insight into the molecular principles of biosynthetic or hormone signaling pathways. The unifying principle is aiming at processes and molecular targets that are unique to arthropods and ideally to narrower insect taxa representing pests or disease vectors. While some strategies of obtaining the desired compounds for chemical intervention rely on rational, structure-based design or computational power, others exploit technologies allowing automated, high-throughput screening of large chemical libraries. All avenues leading to selective and environmentally safe pest control are valid as we face the imminent threat of the declining world insect population. 相似文献
9.
大豆分离蛋白对幼建鲤肝胰脏发育及消化道蛋白酶活力的影响 总被引:9,自引:0,他引:9
研究了大豆分离蛋白(SPI)对10~35g幼建鲤Cyprinus carpio Var.Jian肝胰脏发育及消化道蛋白酶活力的影响。结果表明:饲料中用SPI替代鱼粉蛋白水平对幼建鲤肝胰指数、肝胰脏中的胰蛋白酶、凝乳蛋白酶活力以及肠道中胰蛋白酶、凝乳蛋白酶活力影响极显著(P<0.01)或显著(P<0.05),随着SPI替代鱼粉蛋白比例的增加,蛋白酶活力均极显著下降(P<0.01),肝胰指数显著升高(P<0.05)。用SPI替代鱼粉蛋白后,可引起幼建鲤消化能力下降,肝胰脏和肠道等消化器官的发育受阻,胰蛋白酶和凝乳蛋白酶的活力降低,饲料利用率下降;SPI中胰蛋白酶抑制因子是引起上述症状的重要因素之一。 相似文献
10.
桐乡市秋种春养推广与应用 总被引:1,自引:0,他引:1
由于大气污染的日趋严重 ,桐乡市从 1994年起试行秋种春养 ,至 1999年饲养量占春期蚕种总量的 6 4.4 % ,取得了单产、茧丝质量和经济效益提高的较好效果 相似文献