水稻细胞质雄性不育恢复系ZSP-1恢复基因的初步定位

调查了用细胞质雄性不育新恢复系ZSP－1配制的杂交组合珍汕97A／ZSP－1和星A－ZSP－1的F1的结实率及F2个体花粉育性，发现恢复系ZSP－1的恢复性是由2对独立遗传基因控制。在此基础上，选用了与野败型雄性不育恢复基因Rf-3和Rf-4紧密连锁的RFLP标记对2个F2群体进行连锁分析，发现ZSP－1具有的2个恢复基因与这些标记紧密连锁，初步把ZSP－1的恢复基因定位于Rf-3和Rf-4区域。     

Zero Point of Charge Determination of Monoionic Montmorillonites by Transport Number Method

The zero points of charge (ZPC) of a natural bentonite and those of its homoionic forms (Na, Ca and Al) were determined by the transport number method. The influence of the interlayer cation was observed in the different pH values of the ZPC obtained. No influence of the water contains was observed.     

不同降雨带上的土壤侵蚀状况分析

利用遥感和地理信息系统技术对我国不同降雨量等级下的土壤侵蚀情况进行了分析 ,结果表明 ,轻度以上水蚀的百分比和水蚀综合指数的最高值都出现在降雨量为 2 5 0～ 40 0 m m的半干旱、农牧交错区的带上 ,分别为 5 5 .7%和 182。风蚀综合指数、冻融侵蚀综合指数和土壤侵蚀综合指数的最高值分别为 6 40 ,192和 44 7,均出现在降雨量小于 2 0 0 mm的干旱地带上。在降雨量大于 16 0 0 mm的带上不存在冻融侵蚀。在湿润、潮湿和过湿的地带上主要以水蚀为主 ,均占 96 %以上。在半湿润地带上 ,水蚀也占优势 ,占 76 .1%。在半干旱地带上 ,水蚀、风蚀和冻融侵蚀接近于各占 30 %。在干旱地带上 ,以风蚀为主 ,占 5 8.6 %。     

Diversity of rhizobia isolated from an agricultural soil in Argentina based on carbon utilization and effects of herbicides on growth

Seventy-six rhizobial isolates belonging to four different genera were obtained from the root nodules of several legumes (Vicia sativa, Vicia faba, Medicago sativa, Melilotus sp., Glycine max and Lotus corniculatus). The action of five commonly used herbicides [2,4-dichlorophenoxyacetic acid (2,4-D), glyphosate (GF), dicamba, atrazine and metsulfuron-methyl] on the growth of rhizobial strains was assessed. Subsequently, GF and 2,4-D were tested in a minimum broth as C and energy sources for 20 tolerant strains. The ability of these strains to metabolize different carbon sources was studied in order to detect further differences among them. Tolerance of the bacteria to agrochemicals varied; 2,4-D and GF in solid medium inhibited and diminished growth, respectively, in slow-growing rhizobial strains. Among slow-growing strains we detected Bradyrhizobium sp. SJ140 that grew well in broth + GF as the sole C and energy source. No strain was found which could use 2,4-D as sole C source. The 20 strains studied exhibited different patterns of C sources utilization. Cluster analysis revealed three groups, corresponding to four genera of rhizobia: Rhizobium (group I), Sinorhizobium (group II) and Mesorhizobium–Bradyrhizobium (group III). On the basis of the results obtained on responses to herbicides and C sources utilization by the isolates investigated, it was possible to differentiate them at the level of strains. These results evidenced a considerable diversity in rhizobial populations that had not been previously described for Argentinean soils, and suggested a physiological potential to use natural and xenobiotic C sources.     

柴达木枸杞发育期监测及其相关气象条件分析

本文通过对2011-2013年柴达木盆地枸杞的发育期的观测及其出现日期的不同,确定了"柴杞"的各发育期特征,得出各发育期时段。根据此期间的气象资料,通过对气象条件对发育期的影响分析,得出了其相关气象条件的特征。     

Influence of laying on iron metabolism in quail

Haematological and iron content values for liver, spleen, intestines, blood, ovary and eggs were determined in female quails, from the prelaying state to full laying. A drop in hematocrit, haemoglobin and in the liver stores occurred at the onset of laying (48 to 51 d of age), but these values recovered after 5 to 10 d. The iron lost in eggs (0.3 mg Fe/egg) was responsible for this. An active homeostatic control must be necessary to supply adequate iron for both eggs and blood formation. Quails fed on an iron-deficient diet distributed iron preferentially to the haematopoietic processes, at the expense of the iron content of the eggs and a subsequent reduction of viability.     

Pulmonary vascular reactivity of the newborn pony foal

Adult ponies develop pulmonary hypertension at altitude (Bisgard, Orr and Will 1975), but the neonatal response to acute hypoxaemia is unknown. Seven foals aged five days were instrumented with a systemic and a Swan-Ganz pulmonary artery catheter while anesthetised and intubated. Cardiac index, pulmonary (PAP) and systemic (SAP) vascular pressures were measured as the foals breathed gas mixtures with FI02 of 8 to 94 per cent. Because foramen ovale or ductus arteriosus shunts might have altered thermodilution cardiac index measurements in the stressed foals, the ratio, PAP/SAP was calculated to define relative circulatory reactivity. Three foals, two of which were full siblings, had very marked elevation of PAP/SAP from 0.6 to 1.41 at low inspired oxygen tensions. Four different foals attained maximal PAP/SAP of only 0.2 to 0.92 at similarly low oxygen tensions (P less than 0.0001). Thus, pulmonary vascular reactivity to ventilatory hypoxaemia varied greatly in pony foals of the same age. The exaggerated reactivity in related foals suggested that, as in cattle, a genetic predisposition to develop reactive pulmonary hypertension under hypoxaemic stress may exist.     

Detection of bovine viral diarrhea virus (BVDV) in seropositive cattle

Detection of bovine virus diarrhoea virus (BVDV) in one vaccinated beef cattle and three non-vaccinated dairy herds was investigated on peripheral blood leukocytes (PBL) with or without previous treatment followed by a capture ELISA (cELISA). Using the combination of PHA and polycation treatment, PBL from 229 seropositive cattle were studied and could be classified in four different states of BVDV infection. Lysed PBL from four animals were directly positive in cELISA (Category I), PBL of 17 animals were positive after PHA stimulation (Category II), 15 animals were positive only after PHA stimulation plus polycation treatment (Category III), while virus could not be detected in 193 seropositive cattle. Wild-type BVDV strains were isolated by co-culture on polycation-treated MDBK cells from 11 of these seropositive animals. BVDV antibodies of these same animals were able to neutralize their own virus, indicating that virus persists in PBL in spite of strain-specific antibodies. No apparent change of leukocyte subpopulations could be detected in any category of virus-positive animals. Thus, BVDV may be present in the PBL of some cattle, even in the presence of a specific active immune response.