棉花耐盐变异体的RAPD分析及抗盐生理研究

The salt-tolerance variation of cotton-Shannong 011 obstained from the offsprings of introducing bluish dogbane (Apocynum venetum) DNA into the Lumian No.6(Gossypium hirsutum) by pollen tube pathway,was used for RAPD analysis. 140 primers used for detecting the polymorphism. Only two primers (OPX一     

棉秆重组方材制备工艺与试验

以棉秆为原料,通过单因素试验研究密度、施胶量和热压温度对棉秆重组方材力学性能的影响.结果表明,在试验范围内,棉秆重组方材的抗弯弹性模量、抗弯强度和顺纹抗压强度随着密度(0.5、0.6和0.7 g/cm3)和施胶量(添加量为绝干棉秆束质量的8％、10％和12％)的增加而增大,随着热压温度的升高(由160℃C升到180℃℃C)先增大后有所减小(由180℃升到200℃).在其他工艺条件相同的情况下,酚醛胶棉秆重组方材的力学性能明显好于三聚氰胺改性脲醛胶棉秆重组方材.与人工林木材比较,密度为0.7 g/cm3的棉秆重组方材,其力学性能和人工林杨木的成熟材相当.     

棉秆粉碎收获机的设计

利用旋转甩刀的切割及冲击作用对棉秆进行粉碎，并利用甩刀高速旋转产生的惯性和气流对粉碎的棉秆进行抛送。在田间试验的基础上，通过理论探讨，对棉秆粉碎收获机的基本原理、主要部件及技术参数，尤其是甩刀转速进行分析、设计，设计了与中型拖拉机配套的棉秆粉碎收获机。     

Selecting cotton yield response function to estimate profit-maximizing potassium fertilization rates for cotton production in Tennessee

Recent research has shown that stochastic yield response functions fit data better than deterministic yield response functions; however, little research exists comparing profit-maximizing fertilizer rates for upland cotton (Gossypium hirsutum L.) using stochastic and deterministic yield response functions. The objective of this research was to determine the most appropriate yield response functional form from which to determine the profit-maximizing potassium (K) rate for cotton in Tennessee. Data were used from a nine-year K fertilizer experiment in Jackson, Tennessee. Quadratic, quadratic-plus-plateau, linear response plateau, and linear response stochastic plateau response functions were estimated to determine the yield response function that best fit the data. The linear response stochastic plateau function was the most suitable yield response function for the data. The profit-maximizing K rate ranged from 65.2 to 74.3 kg K ha^?1. Misspecification of the yield response function recommended over-application of K fertilizer and decreased the producer's short-term profits.     

Effects of cotton (Gossypium hirsutum L.) straw and its biochar application on NH3 volatilization and N use efficiency in a drip-irrigated cotton field

Reducing ammonia (NH₃) volatilization is a practical way to increase nitrogen (N) fertilizer use efficiency (NUE). In this field study, soil was amended once with either cotton (Gossypium hirsutum L.) straw (6 t ha^?1) or its biochar (3.7 t ha^?1) unfertilized (0 kg N ha^?1) or fertilized (450 kg N ha^?1), and then soil inorganic N concentration and distribution, NH₃ volatilization, cotton yield and NUE were measured during the next two growing seasons. In unfertilized plots, NH₃ volatilization losses in the straw-amended and biochar-amended treatments were 38–40% and 42–46%, respectively, less than that in control (i.e., unamended soil) during the two growing seasons. In the fertilized plots, NH₃ volatilization losses in the straw-amended and biochar-amended treatments were 30–39% and 43–54%, respectively, less than that in the control. Straw amendment increased inorganic N concentrations, cotton yield, cotton N uptake and NUE during the first cropping season after application, but not during the second. In contrast, biochar increased cotton N uptake and NUE during both the first and the second cropping seasons after application. Furthermore, the effects of biochar on cotton N uptake and NUE were greater in the second year than in the first year. These results indicate that cotton straw and cotton straw biochar can both reduce NH₃ volatilization and also increase cotton yield, N uptake and NUE. In addition, the positive effects of one application of cotton straw biochar were more long-lasting than those of cotton straw.     

温度和盐浓度对棉籽发芽的影响

以新棉33B为试验材料,研究了不同温度和盐浓度条件对棉籽发芽势及发芽率的影响。结果表明：棉籽发芽受温度和盐度共同影响。温度和盐度对棉籽发芽率存在互作关系。在重度盐碱地种植棉花,采取推迟播期和覆膜等提高地温的办法,可以解决棉田出苗敏感问题,     

不同施氮量对枣棉间作棉花根系形态与生理特性的影响

研究枣棉间作下不同施氮水平 (0、150、450 和750 kg·hm^-2)对棉花根系形态、生理指标的效应,分析氮素对根系形态与生理特性的影响。结果表明：在施氮量0、150、750 kg·hm^-2时,主根长度增速较慢,根长密度、干物质积累量降低,根系活力、氮素代谢相关酶NR活性减弱,可溶性蛋白质、可溶性糖含量下降,远冠区N₀、N₁₀、N₅₀与N₃₀相比,根长密度0~20 cm土层分别下降18.18%、25.97%、29.87%,20~40 cm土层分别下降31.43%、38.29%、41.14%。根系活力变化最为显著,在棉花生育T1时,近冠区N₀、N₁₀、N₅₀与N₃₀相比分别下降36.01%、27.45%、9.74%,远冠区分别下降34.32%、23.53%、10.10%,说明氮素营养缺乏会加速棉花根系的衰老进程,抑制根系生长发育。因此,适当的施氮量,可延缓根系衰老。     

抗虫棉新品种石早98的选育

石早98是以SGK321为母本、583为父本杂交选育而成的中早熟棉花新品种,具有早熟、优质、高产、抗病等特点,适宜在冀东早熟棉区和黄河流域棉区晚春播种植。介绍了石早98的选育过程、特征特性及栽培技术要点。     

棉花抗病丰产核雄性不育两用系的选育

[目的]选育棉花抗病丰产核雄性不育两用系。[方法]利用棉花优良骨干核不育系GA18,选育出了抗病丰产新不育系RA14、RA15。[结果]RA14、RA15均具有育性稳定、败育彻底、配合力高和植株生长势强等特点;组合测配表明,RA14宜与品质优的恢复系搭配,RA15可与大铃的恢复系搭配。[结论]两个新不育系材料各具优点,可选育出不同类型的棉花新组合,为棉花抗病丰产杂交品种选育提供新材料。     

高寒地区番茄棉铃虫的防治

广灵是京、津、唐、保定等地的远郊蔬菜生产基地。近几年,棉铃虫对番茄的为害日益严重,为此采用综合措施防治,效果显著。