冬小麦对不同土壤水分的生理和形态响应

采用深桶栽培结合测坑法，从冬小麦反青至蜡熟期保持不同的土壤水分，分生育期对小麦的形态、生理和根系进行了测定。结果表明：调控土壤水分可明显改变冬小麦根、冠生长量比率。适宜的土壤水分胁迫（田持的５０％－６０％）可促进冬小麦根系发育，高土壤水分更有利于地上部生长。土壤水分长期低于田间持水量的６０％时，较显著地叶片的增大，从而减小截获光能的总叶面积，最终降低生物学产量和经济产量。土壤水分由“田持”的４６％升高到５５％，光合速率增幅不大，由５５％提高到６４％，光合速率出现跃迁式增高，土壤水分超过６４％后，光合速率几乎为等值。说明光合作用对土壤水分存在一个“阈值”反应，此值为土壤田间持水量的６５％左右。冬小麦的蒸腾速率随土壤水分递增而一直递增；综合考虑蒸腾速率与光合速率及水分利用效率之间关系，可以得出高土壤水分条件下冬小麦存在奢侈蒸腾耗水现象。     

不同类型玉米生理特征与产量的关系

通过对不同类型玉米的产量及光合生理指标的测定表明，在合理密度下，玉米的产量主要由叶片光合能力所决定，特别是生殖生长期中上部叶片的净光合速率。同时表明登海6号在吐丝期下部叶片的净光合速率、叶绿素含量、光合有效辐射、气孔导度均高于其他品种（组合）且差异显著，在乳熟期登海6号中上部叶片净光合速率、叶绿素含量、气孔导度均高于其他品种（组合）且差异显著，并总结了高山生态条件下，玉米高产的生理特征：吐丝期前下部叶片净光合速率高，于粒灌浆期中上部叶片净光合速率高且持续时间长，茎叶物质输出率高。     

Study on the Changes of the Amount of Microorganism and Microbial Biomass Carbon in Soil of Greenhouse Cropping

通过对四川省温江、双流两地不同设施种植年限土壤中微生物数量及其生物量碳的研究,结果表明,不同设施种植年限大棚土壤中的微生物数量是露地的1.63~3.50倍,且大棚土壤中好气性微生物总数随种植年限的增加有逐渐降低的趋势,三大微生物数量占微生物总数的比例中,细菌表现为随设施种植年限的增加而增加;放线菌和真菌表现为下降;露地土壤微生物多样性指数分别是设施年限为1a、2a和4a的大棚土壤的1.29倍、2.28倍和3.45倍,前者明显高于后者。随设施年限的增加,土壤微生物生物量碳、有机碳及微生物对有机碳的利用率都表现     

云南栽培稻生态型矿质元素含量的多样性

用ICP-AES测定了新平县相同生态条件下种植653份云南稻资源糙米8种矿质元素含量，并按丁颖的栽培稻生态型对其遗传多样性进行了研究。结果表明，云南水稻改良品种糙米P、Fe和Zn含量比地方稻种分别下降10.53%、14.76%和35.16%，但改良品种特别是粳稻Ca含量比地方种高, 8种矿质元素以Ca的多样性指数最大；糙米P、Ca、Mg、Fe、Zu、Cu和Mn平均含量以粳稻的Mg、Fe和Zn，水稻的P、K和Mg，陆稻的Fe和Zn，糯稻的K和Fe，早稻的Mg和Fe相对较高。8种矿质元素平均遗传多样性指数依次为粳>籼,陆>水,粘>糯,早中稻>晚稻和地方种>改良种,且P>K>Mn>Mg>Cu>Zn>Fe>Ca；其变异系数依次为Fe>Ca>Cu>Zn>Mn>K>Mg >P。     

低温胁迫下钼对冬小麦光合作用特性的影响

研究了低温胁迫下施钼对冬小麦钼高效品系97003和钼低效品系97014叶片光合参数的影响。结果表明，低温胁迫下施钼显著提高2个品系叶片的净光合速率(P_n)和气孔限制值(L_s)，显著降低叶片气孔导度(G_s)、胞间CO₂浓度(C_i)和蒸腾速率(T_r)。随着低温处理时间的延     

1-MCP对磨盘柿成熟软化的影响

采用不同浓度的1-MCP(1-甲基环丙烯)和不同处理温度对磨盘柿果实成熟软化的影响进行了研究.结果表明,适宜的1-MCP处理(浓度0.1～1 uL/L)可明显地延缓磨盘柿果实硬度下降,降低果实呼吸强度,推迟呼吸高峰的出现,并能显著地抑制果实乙烯释放,推迟其成熟软化,对延长磨盘柿贮藏期具有一定的作用.     

不同处理对蘑菇与黄豆芽混合汁营养成分的影响

采用不同工艺条件测定蘑菇与黄豆芽混合汁中营养成分的含量。经测定得知,蘑菇：黄豆芽：水：1：2：3,利用内源酶水解24h,混合汁中水溶性含氮物、VC含量较高,利用内源酶或盐酸水解可显著提高还原糖浓度。     

Screening sorghum genotypes for salinity tolerant biomass production

Genetic improvement of salt tolerance is of high importance due to the extent and the constant increase in salt affected areas. Sorghum [Sorghum bicolor (L.) Moench] has been considered relatively more salt tolerant than maize and has the potential as a grain and fodder crop for salt affected areas. One hundred sorghum genotypes were screened for salinity tolerance in pots containing Alfisol and initially irrigated with a 250-mM NaCl solution in a randomized block design with three replications. Subsequently 46 selected genotypes were assessed in a second trial to confirm their responses to salinity. Substantial variation in shoot biomass ratio was identified among the genotypes. The performance of genotypes was consistent across experiments. Seven salinity tolerant and ten salinity sensitive genotypes are reported. Relative shoot lengths of seedlings were genetically correlated to the shoot biomass ratios at all stages of sampling though the relationships were not close enough to use the trait as a selection criterion. In general, the whole-plant tolerance to salinity resulted in reduced shoot Na⁺ concentration. The K⁺/Na⁺ and Ca²⁺/Na⁺ ratios were also positively related to tolerance but with a lesser r ². Therefore, it is concluded that genotypic diversity exists for salt tolerance biomass production and that Na⁺ exclusion from the shoot may be a major mechanism involved in that tolerance.     

Mapping genes for grain protein concentration and grain yield on chromosome 5B of Triticum turgidum (L.) var. dicoccoides

Grain protein concentration (GPC) is an important quality factor in durum wheat [Triticum turgidum (L.) var. durum]. Due to the strong environmental influence on GPC, molecular markers linked to quantitative trait loci (QTL) affecting GPC have the potential to be valuable in wheat breeding programs. Various quantitative traits in a population of 133 recombinant inbred chromosome lines were studied in replicated trials at three locations in North Dakota. Segregation for GPC, 1000-kernel weight, gluten strength, heading date, and plant height was observed. By relating phenotypic data to a linkage map obtained from the same population, three QTL affecting GPC, and one affecting yield were identified. The genotypic coefficients of determination for both traits were high.     

生姜提取液对牦牛肉保鲜效果的研究

以新鲜牦牛肉为原料,采用生姜提取液(鲜生姜汁∶蒸馏水=1∶5)喷淋处理,结合真空复合膜包装技术,研究在(3±1)℃条件下储藏21 d新鲜牦牛肉的感官品质、细菌总数、p H、挥发性盐基氮(TVBN)含量等指标的变化规律。结果表明,生姜提取液处理可保持牦牛肉较高的感官品质,降低水分损失率和菌落总数增长速度,储藏期间肉的p H处在鲜肉范围内,有效减缓了TVB-N含量的升高,明显延长了牦牛肉的储藏时间,具有较好的保鲜效果。