Intra‐specific variation for salt tolerance in a potential oil‐seed crop,brown mustard (Brassica juncea (l.) Czern. and Coss.)

Thirty eight accessions of brown mustard (Brassica juncea (L.) Czern. and Coss.) were screened after two weeks growth in solution culture containing 120 mol m‐³ NaCl. Considerable variation for salt tolerance was observed in this set of germplasm, since some accessions showed relatively vigorous growth in saline medium.

In order to determine the consistency of degree of salt tolerance at different growth stages of crop life cycle two salt tolerant accessions, P‐15 and KS‐51 and two salt sensitive 85362 and 85605 were tested at the adult stage in 0(control), 100 and 200 mol m^‐3 NaCl. Both the tolerant accessions produced significantly greater fresh and dry biomass and had considerably higher seed yield than those of the salt sensitive accessions. Analysis of different ions in the leaves showed that salt tolerant accessions contained greater amounts of Na⁺, K⁺ and Ca²⁺ than the salt sensitive accessions, although they did not differ significantly for leaf Cl^‐. Only one salt tolerant accession P‐15 had greater leaf K/Na ratio and K⁺ versus Na⁺ selectivity compared with the tolerant KS‐51 and the two salt sensitive accessions.

From this study it was established that there is a considerable variation for salt tolerance in B.juncea which can be exploited by selection and breeding for improvement of its salt tolerance. Since the degree of salt tolerance in B.juncea does not change at different growth stages of the crop life cycle, selection for salt tolerance at the initial growth stages could provide individuals that would be tolerant at all other growth stages. Accumulation of Na⁺, K⁺ and Ca²⁺ in the leaves are important components of salt tolerance in B.juncea.     

不同类型叶用芥菜核型分析

采用根尖染色体压片技术对大叶芥、小叶芥和白花芥的染色体核型进行分析。分析结果表明,大叶芥染色体数目为2n=4x=AABB=36,核型公式为2n=4x=14m+18sm+4st,核不对称系数为66.33%,属于"3B"型;小叶芥染色体数目为2n=4x=AABB=36,核型公式为2n=4x=30m+4sm+2st,核不对称系数为58.21%,属于"2B"型;白花芥染色体数目为2n=4x=AABB=36,核型公式为2n=4x=22m+12sm+2st,核不对称系数为61.61%,属于"2B"型。3种不同类型叶用芥菜没有出现染色体数目的变化,都属于小染色体,多数染色体为中部着丝点,只有在染色体长度、着丝点位置、核不对称系数等核型组成上出现了细微的差异,说明3种不同类型叶用芥菜间具有相似的遗传特性。核不对称系数,大叶芥白花芥小叶芥,在进化关系上,小叶芥属于相对原始的类型,大叶芥和白花芥进化程度更高。     

Gene flow from transgenic oilseed Brassica juncea (L.) Czern. into weedy Sinapis arvensis L. (wild mustard)

Gene flow from acetolactate synthase‐resistant (HR) Brassica juncea oilseed canola to related weed, Sinapis arvensis (density 1 plant/m²) was assessed in a 100 m² field plot of HR B. juncea. Two HR F₁ hybrids (H1 and H2) were detected among 109 951 seedlings screened with imazethapyr (hybridization frequency – 1.8 × 10^?5). Hybridity was confirmed using flow cytometry, B. juncea‐specific amplified fragment length polymorphisms (AFLPs) markers, genomic in situ hybridization (GISH) and PCR‐based detection of B. juncea's HR gene. H1 and H2 had 2n = 27 and 2n = 45 chromosomes, corresponding 3x (SrAB) and 5x (SrAABB) genomic structures and reduced male fertility, 3.2 and 16.6% pollen viability, respectively. H1 was self‐incompatible, whereas H2 set seed when selfed (B. juncea trait). Selfed F₂, F₃ and F₄ plants showed HR trait persistence and vigorous growth and high (80–100%) pollen fertility in 22% and 39% of the F₂ and F₃ plants, respectively. No progeny were obtained from F_1, F₂ or F₃ hybrids × S. arvensis backcrosses, suggesting the likelihood of introgression of traits is low to negligible.     

Mineralization of Nitrogen from Biofuel By-products and Animal Manures Amended to a Sandy Soil

Transformations of nitrogen (N) from poultry litter (PL), dairy manure compost (DMC), anaerobically digested fiber (ADF), Perfect Blend 7–2–2 (PB), a compost/litter mixture (C/L), dried distillers grains from ethanol production (DG), and mustard meal from biodiesel production (MM) applied to a Quincy fine sand were investigated in an incubation experiment over 210 days. The cumulative release totals of available N after 210 days were 61, 61, 56, 44, 29, 2, and –2% for the total N in MM, PB, DG, PL, C/L, DMC, and ADF, respectively. With application of MM and DG, ammonium (NH₄-N) accumulated initially in the soil with very little nitrification, possibly because of inhibition of nitrification related to chemical compounds in the amendments. Mineralization of organic N to NH₄-N and nitrate (NO₃-N) was relatively slow from MM- and DG-amended soils, indicating the potential for using biofuel by-products as slow-release N sources for plants.     

Effects of Sulfur and Water Supply on Quantitative and Qualitative Traits of Indian Mustard

Oilseed production can be affected in arid and semi-arid regions that are exposed to water shortages. Nevertheless, cultivation of drought-resistant crops such as Indian mustard is a suitable way to gain acceptable yields. Effects of different levels of irrigation and sulfur (S) fertilizer on the quantity and quality parameters of mustard (Brassica juncea) were assessed in a trial at the Indian Agricultural Research Institute, New Delhi, during 2007–2008 and 2008–2009 growing seasons. The experiment was carried out in a split plot as randomized complete block design with three replications. The experiment treatments consisted of three irrigation levels [no irrigation, one irrigation at 45 days after sowing (DAS), and two irrigations at 45 DAS and 90 DAS] in main plots and four sulfur levels (S; 0, 15, 30, and 45 kg S ha^?1) in subplots. The results showed that in the two successive years of the experiment, the number of siliquae/plant, length of siliqua, number of seeds/siliqua, and 1000-seed weight increased significantly with increasing the level of irrigation, which resulted in greater seed yield than no irrigation. Also, mustard plants irrigated two times showed the greatest values of nitrogen (N), protein, and oil content of the seeds over no irrigation in both years of this study. The oil yield and S content in the seed of mustard increased significantly with increasing the level of irrigation in both years. Number of siliquae/plant, siliqua length, number of seed/siliqua, and 1000-seed weight increased significantly with increasing the rates of S up to 45 kg S ha^?1 in both years of experimentation; however, in 2008–2009 the difference between application of 30 and 45 kg ha^?1 S was not statically significant. Also, the seed yield, N, protein, oil, and S contents in seeds of mustard increased significantly with increase in the level of applied S in both years.     

咳喘穴位敷贴对哮喘大鼠Th1/Th2免疫平衡的影响

目的 探讨咳喘穴位敷贴对哮喘大鼠辅助性T淋巴细胞1（Th1）/辅助性T淋巴细胞2（Th2）免疫平衡的影响。方法　60只雄性SD大鼠随机分为6组：正常对照组、哮喘模型组、生芥子组、生炒各半组、炒芥子组、地塞米松组,每组10只。采用卵清蛋白致敏并激发的方法制备大鼠慢性哮喘模型,白芥子不同配比咳喘穴位敷贴散贴敷穴位干预治疗。采用酶联免疫吸附剂测定法（ELISA）测定各组大鼠血清中干扰素（IFN）-γ、白介素（IL）-4、白介素（IL）-13的含量。结果 与正常对照组比较,哮喘模型组大鼠血清IFN-γ含量明显降低,而IL-4、IL-13的含量明显升高（P<0.01）。与哮喘模型组比较,生芥子组、生炒各半组、炒芥子组和地塞米松组的大鼠血清IFN-γ含量明显升高,而IL-4、IL-13的含量明显降低（P<0.01）,各治疗组之间差异无统计学意义（P>0.05）。结论 咳喘穴位敷贴能够调节哮喘大鼠Th1/Th2免疫平衡,改善炎症反应,从而改善哮喘病情。     

茎瘤芥霜霉病抗性评价标准的建立与应用

为了给茎瘤芥霜霉病研究提供抗性评价依据,人工模拟研究了茎瘤芥叶面损伤对其主要经济性状的影响。结果表明：茎瘤芥从上至下的4片完全展开的叶在瘤茎鲜重的增加中起着决定性的作用,特别是这4片叶的总叶面积受损超过1/2后,其受损程度与植株收获物瘤茎的产量成比例变化,受损越重,瘤茎越轻,同时对余下的主要经济性状影响较小。以此为据,结合前人研究经验提出了茎瘤芥霜霉病的分级标准与抗性型划分标准。     

茎瘤芥采收期营养和安全品质变化规律研究

在茎瘤芥采收期,每3 d采收1次,分析测定瘤茎Vc、可溶性糖、游离氨基酸、硝酸盐及亚硝酸盐含量,结果表明,可溶性糖和Vc含量在采收期均呈先降后升的规律,面游离氨基酸、硝酸盐则一直呈下降趋势,亚硝酸盐变化较复杂;考虑产量和品质因素,建议茎瘤芥在雨水节6 d(现蕾前2 d)后收获.     

修复镉污染土壤的油菜品种的筛选及吸收累积特征研究--高积累镉油菜对土壤中难溶态镉的活化及吸收研究(Ⅱ)

以水培试验筛选出高吸收累积镉油菜品种川油Ⅱ-10、白芥、绵阳蛮油菜和印度芥菜为材料,对油菜和印度芥菜的根际土壤和非根际土壤性质进行比较得出,根际土壤的DTPA—Cd显高于非根际土壤．油菜和印度芥菜均可活化吸收土壤中难溶态的镉．土壤中加入碳酸镉对油菜和印度芥菜乍长没有明显影响．油菜和印度芥菜地上部吸收镉量明显高于根部。     

茎瘤芥种子萌发期过氧化物酶的研究

[目的]较为系统地研究茎瘤芥种子萌发期过氧化物酶（POD）的有关酶学特性。[方法]以3个品种的茎瘤芥种子为试材,测试其7d内种子的发芽情况,探讨了种子发芽韭、发芽势与其过氧化物酶的相关性。[结果]以愈创木酚为底物,产物的最大吸收波长为470mm。永安小叶POD的最适pH值为5．6,最适温度为20℃,动力学参数Km=0．093mol／L,Vmax=0．14OD／min;优榨1号POD的最适pH值为4.8,最适温度为30℃,动力学参数Km=0．046mol／L,Vmax=0．088 OD／min;乾兴榨菜POD的最适pH值为5．2,最适温度为30℃,动力学参数Km=0．063mol／L,Vmax=0．108 OD／min。动力学分析表明,POD与愈创木酚结合力最强,POD热稳定性较好,在70℃保温30min仍有50％以上的活力,维生素C和亚硫酸钠对POD活力抑制效果好。[结论]茎瘤芥种子的发芽力与其过氧化物酶活力的增减具有同步性。