不同灌水下限对设施滴灌无土栽培红掌水分利用和生长的影响

为指导设施基质盆栽红掌科学灌溉,该文以连栋温室基质盆栽花卉-红掌为试材,控制灌水下限分别为基质持水率(θFC)的90%(T1)、80%(T2)、70%(T3)、60%(T4)和50%(T5),研究了滴灌条件下不同灌水下限对基质含水率、田间水利用、红掌生长和耗水的影响。结果表明:供试基质田间水利用系数仅0.4～0.5左右,随着灌水下限的降低,基质含水率、田间水利用系数均降低,灌溉渗漏损失量增加,灌水周期延长;各处理红掌花朵数差异不大,与T1相比较,灌水下限为60%θFC时,红掌佛焰苞大小未受影响,株高和冠幅显著增加了19.3%和14.7%(p=0.05),提升了观赏品质,其余处理除T5佛焰苞减小外,均与T1差别不大;试期内红掌耗水量介于2 522～2 986 g/盆之间,与T1相比较,T2、T3、T4和T5耗水量降低了4%～16%;60%θFC处理在降低耗水量的同时,提高了品质,是适宜的灌水下限。     

油用紫苏种质主要农艺性状及品质特征鉴定与评价

为筛选优异紫苏种质资源及优良育种亲本,提高紫苏育种效率,本研究以159份油用紫苏种质资源为试验材料,对不同紫苏种质11个主要农艺性状及5个关键品质特性进行了鉴定、变异分析、主成分及系统聚类分析等多元统计分析与评价。结果表明,供试紫苏种质主要农艺性状及品质特征的变异系数介于2.60%~35.42%之间,各种质间主要农艺性状及品质特性遗传变异丰富,类型广泛,选择利用的前景较好;主成分分析将主要农艺性状及品质特征聚为6个主成分,即分枝数因子、α-亚麻酸因子、油酸因子、生育期因子、千粒重因子和产量因子,总变异贡献率分别为40.943%、21.549%、12.332%、5.810%、4.486%和4.243%,累计贡献率为89.36%,可代表所考察性状的大部分信息;系统聚类将供试材料聚为五大类群,表明不同类群材料间各农艺性状及品质特征存在较明显的特异性;此外,本试验确定了主要农艺性状及品质特征划分标准,揭示了叶色、粒色等不同类型紫苏种质在产量、α-亚麻酸含量等关键指标上的差异性规律,评价筛选的高产及特异性明显的优异种质。本研究结果为生产中应用优异基因资源及改良育种亲本提供了一定的理论依据。     

红掌基因工程育种进展、问题与对策

红掌是极具观赏性和商业开发价值的盆栽植物和切花花卉,品种改良是推动其产业持续发展的根本。周期较长、生殖障碍、遗传基础不明晰等限制了红掌常规育种的发展,而基因工程具有高效、定向、打破种属隔离的优势,在红掌育种中有着广阔的应用前景。二十年来,红掌基因工程研究取得了巨大进展,本文回顾了该领域技术体系的发展历程,综述了转基因在红掌抗病害、虫害、低温等胁迫及花色、花期等多个性状改良中的应用研究现状,并对存在的问题和发展前景予以评析,为加快具有我国自主产权的红掌新品种选育提供参考。     

黄瓜耐盐种质资源的筛选与评价

为了明确黄瓜种质对氯化钠的不同耐性,解析黄瓜耐盐的分子机理,本研究以耐盐种质MC2065、盐敏感种质白黄瓜和21份其他黄瓜种质为材料,设置5个NaCl浓度,50、100、150、200、250 mmol·L^-1分别开展适宜NaCl浓度筛选,以及适宜浓度处理后耐盐指数、叶绿素、保护酶等9个生理生化指标的测定与分析。结果表明,100和150 mmol·L^-1可以作为耐盐鉴定的适宜浓度。NaCl浓度为100 mmol·L^-1时,白黄瓜盐害指数为35.94%,出现明显盐害胁迫,而MC2065盐害指数为4.69%,未表现出明显盐害症状;NaCl浓度为150 mmol·L^-1时,两个材料均表现明显盐害症状,白黄瓜出现半数以上叶片枯萎,而MC2065出现半数以下叶片枯萎。聚类分析发现,21份材料分为3个类群,第一类群包括ZQ3、N26-5-1、寿水1、DRTJY-2、莱西、翠玉、20S077-1,属于耐盐种质;第二类群包括DJ04、DY-1、XY1、YY9123、M2XT、D1503、X805,属于中耐盐种质;第三类群包括F6-3-1、SJ11-1、XB23、20S091-1、HLT-921h、AZ-1、DRT345,属于盐敏感种质。主成分分析发现,黄瓜种质综合得分趋势与聚类分析、黄瓜幼苗存活率高低趋势基本一致。本研究结果为黄瓜耐盐机理的研究提供了参考,也为黄瓜耐盐品种的育种工作奠定了基础。     

大白菜-结球甘蓝4号单体异附加系的鉴定

大白菜-结球甘蓝异附加系是利用结球甘蓝的优良基因对大白菜进行品种改良的中间材料,在遗传理论研究和育种实践中均具有重要应用价值。本研究以大白菜-结球甘蓝异源三倍体（AAC, 2n=29）与二倍体大白菜（AA,2n=20）回交一代的自交后代为材料,经过细胞学鉴定,从中筛选出大白菜-结球甘蓝4号单体异附加系,对其减数分裂和植株性状进行了观察与调查。该异附加系的获得为研究芸薹属A、C基因组的亲缘关系,以及向大白菜中导入结球甘蓝的优良基因,扩大种质遗传背景提供了基础材料。     

小麦-长穗偃麦草矮秆种质系的鉴定及遗传分析

矮源是进行小麦矮化育种的基础。本研究对2个小偃麦矮秆种质系31505-1和31505-2进行了分子鉴定和遗传分析。结果表明,31505-1和31505-2是2个不同的矮秆小偃麦易位系,31505-1中易位的偃麦草染色体片段位于2D染色体;对矮秆小偃麦种质系与不同株高材料杂交后代的株高和节间长度进行了分析,发现2个种质系的后代致矮率可达16%~23%,其株高的降低主要由节间长度的变化引起的,其中倒2节间与株高的变化相关性最高。本研究对拓宽小麦矮秆种质资源基础具有一定意义。     

~(60)Co-γ射线对路易斯安那鸢尾种子的辐射效应研究

为探索路易斯安那鸢尾育种的新途径,利用0(CK)、100、200、300 Gy 4个不同剂量的~(60)Co-γ射线对6个路易斯安那鸢尾品种的自交种子进行辐射处理,研究~(60)Co-γ射线对路易斯安那鸢尾种子的辐射效应。结果表明,与CK相比,100 Gy辐射处理可以提高路易斯安那鸢尾种子萌发率和成苗率,并有效促进F1M1花茎伸长和花朵直径增加;200 Gy的辐射处理具有明显的致死效应,种子成苗率显著下降;低于200 Gy的~(60)Co-γ射线辐射对其中5个品种F1M1的花色分离具有促进作用,剂量越高,花色分离率越高;300 Gy辐射处理下,6个品种种子成苗率均低于2%,表明300 Gy具有强烈的致死效应。由此可知,100 Gy辐射处理可以促进种子萌发,用于种苗生产;200 Gy可以作为诱变剂量用于诱变育种;300 Gy则不适宜选作辐射育种剂量。本研究结果为路易斯安那鸢尾的辐射育种技术的应用提供了一定的理论依据和技术参考。     

二倍体与四倍体刺槐组培苗形态和生理性状比较

为了比较二倍体与四倍体刺槐组培苗不同无性系之间的差异,本研究分别测定二倍体刺槐组培苗和人工诱导四倍体刺槐组培苗的形态及生理指标,并进行相关分析。结果表明,多数四倍体刺槐无性系的长势、抗逆性优于二倍体;二倍体与四倍体刺槐不同无性系以及不同形态、生理指标之间存在丰富的变异,其中四倍体刺槐的变异更为丰富;各测定指标之间存在较为复杂的相关关系,在选择育种时,需综合考虑。根据试验结果,结合育种目标,可选育出优良四倍体刺槐无性系,丰富刺槐种质资源,增加遗传多样性。本研究为刺槐倍性育种工作提供了理论依据和科学参考。     

基于机器视觉的红掌检测分级方法

中国盆花销售量随着消费水平的提高而迅速攀升,四大盆花之一的红掌在规模化生产中存在分级标准掌控不统一、分级结果不稳定以及效率低下等问题,制约了红掌产品的规模化生产,影响了红掌的出品质量。该研究提出基于机器视觉技术的红掌分级检测方法,对90株红掌的水平和竖直方向图像采集,经过二值化等处理,从侧视轮廓、俯视轮廓及佛焰苞轮廓特征三方面获取红掌植株的高度、冠幅、佛焰苞片数、苞片横径4项指标的信息, 针对每一项指标提出检测方法。试验结果表明,该方法对植株高度测量误差小于5.4 mm;针对植株冠幅提出了当量直径测量方法,佛焰苞片数测量正确率可达98.9%,苞片横径相对误差最大为6.52%。针对试验所选90盆红掌分级成功率达到97.8%。研究表明,利用机器视觉技术能够很好地实现对红掌盆花的在线检测分级。     

基于表型性状分析构建冀北地区马铃薯核心种质

为合理利用和更好保存马铃薯种质资源,本研究以冀北地区保存的502份马铃薯种质资源为材料,调查了26个表型性状,以不同块茎肉色进行分组,设置简单比例、对数比例、平方根比例和多样性比例4种取样方法,5%、10%、15%、20%、25%和30%共6种取样比例,利用2种遗传距离（欧氏距离和马氏距离）和4种聚类方法（类平均法、最长距离法、最短距离法、离差平方和法）,探讨最佳取样策略,抽选核心种质。利用遗传多样性特征值、t检验、评价参数和系统聚类等方法对核心种质的表型性状进行评价,以及利用主成分分析对核心种质进行确认。结果表明,平方根比例法能够使核心种质更具代表性,20%为最佳取样比例,欧氏距离优于马氏距离,最优聚类方法为最短距离法,最终抽提出100份马铃薯核心种质,占全部种质的19.92%;核心种质的评价和主成份分析结果表明100份核心种质消除了大部分遗传冗余,保留了所有样本的遗传多样性,具有良好的代表性。本研究为马铃薯种质资源的有效利用和种质创新提供了重要的理论依据和实践基础。     

Adjustments of sufficiency ranges of selected ornamentals and turfgrasses for assessing nitrogen status with Dumas‐N data

Abstract

With recent advances in nitrogen (N) analyzers, the Dumas method may replace the Kjeldahl method for the routine diagnosis of N in plants. Since these two methods recover different N fractions and no conversion factor is available to convert Dumas N (Dn) to Kjeldahl N (Kn) data, Kn:Dn ratios were determined for selected ornamentals (anthurium, Anthurium andraeanum Linden; orchid spp. Cattleya, Dendrobium, Oncidium, Phalaenopsis, and Vanda; leatherleaf fern, Rumohra adiantiformis (G. Forst) Ching; tree fern, Asparagus densiflorus (Kunth) Jessop) and turfgrasses (creeping bentgrass, Agrostis palustris Huds. cv. Penncross; bermudagrass, Cynodon dactylon L.). Samples were dried at 70°C for 72 hr and ground to pass a 20‐mesh sieve. Kn was determined by colorimetry after digestion of 0.4 g of tissue using a CuSO₄/TiO/K₂SO₄ catalyst and 10 mL of H₂SO₄ at 450°C for 2 hr. Dn was determined using 0.2 g of sample and a LECO FP‐428 N Analyzer. Over the 0.4–6.6% N range, Dn was a good predictor of Kn; Kn = 0.90 Dn + 0.09 (R²=0.93, p‐model<0.01, n=397 obs.). The Kn: Dn ratio was significantly (p<0.01) affected by plant type (Kn: Dn = 0.85, 0.92, 0.99, and 1.00 for anthurium, turfgrasses, orchid and fern, respectively). The more practical way to use the ratios in routine interpretation was to adjust existing sufficiency ranges with the inverse of these ratios. Adjusted sufficiency ranges (in %N) were 4.9–6.6 for creeping bentgrass, 2.4–4.4 for bermudagrass, and 1.9–3.6 for anthurium. Existing sufficiency ranges for orchid and fern need not be adjusted for Dumas N.     

GUIDE VALUES FOR ANTHURIUM (ANTHURIUM CULTORUM BIRDSEY) GROWN IN EXPANDED CLAY

Coefficients of variation and guide values of nutrients were determined for Anthurium cultorum Birdsey cvs. ‘Baron’, ‘Choco’, ‘Pistache’, ‘President’, ‘Midori’, and ‘Tropical’ grown in expanded clay (inert medium) using drip fertigation. Fully developed leaves after freshly-cut flowers were collected as index parts for chemical analyses at two-month intervals over the period of three years (2002–2004). Investigations were conducted at two specialized commercial farms, recording optimal yielding in terms of quantity and quality. A standard nutrient solution for anthurium hydroponics was used in fertigation. Mean guide values for six analyzed cultivars of Anthurium cultorum Birdsey are (in d.m. leaves): 1.40–1.70% nitrogen (N), 0.30–0.40% phosphorus (P), 3.60–4.50% potassium (K), 1.40–1.80% calcium (Ca), 0.20–0.30% magnesium (Mg), 0.30–0.40% sulfur (S), 46.0–60.0 ppm iron (Fe), 35.0–47.0 ppm manganese (Mn), 54.0– 72.0 ppm zinc (Zn), 5.10–6.50 ppm copper (Cu), and 64.0–83.0 ppm boron (B). Guide values for cvs. ‘Baron’, ‘Choco’, ‘Pistache’, ‘President’, ‘Midori’ and ‘Tropical’ are given in the text of this paper. A diversification was shown in guide values for analyzed cultivars in relation to certain macro- and microelements. Coefficients of variation were determined for nutrient contents in index parts of plants. A very high variation (%) was found for Mn 47.5 and Zn 41.8, high for Mg 38.5, P 32.6, S 30.6, medium for Fe 29.2, Ca 28.0, Cu 23.3 and B 20.3, while low for K 11.4 and N 9.9.     

HPLC determination of chlorophyll and carotenoid pigments in processed green pea cultivars (Pisum sativum L.)

Chlorophyll and carotenoid pigments from six cultivars of processed green peas (Avola, Tristar, Rampart, Turon, Bella, and Greenshaft) were extracted with 100% acetone and analyzed by reversed-phase HPLC. A total of 17 pigments were identified in the pea cultivars including 8 xanthophylls ((all-E)-neoxanthin, (9'Z)-neoxanthin, (all-E)-violaxanthin, neochrome, (all-E)-lutein epoxide, (all-E)-lutein, neolutein B, neolutein A), 4 chlorophyll b related compounds (chlorophyll b derivative, chlorophyll b, chlorophyll b', and pheophytin b), 4 chlorophyll a related compounds (chlorophyll a derivative, chlorophyll a, chlorophyll a', and pheophytin a), and (all-E)-beta-carotene. The efficiency of different extraction procedures using 100% acetone showed that initial extraction followed by three reextractions without holding time between gave a higher extraction yield than no reextraction and 30 or 60 min holding time. All six cultivars contained the same pigments, but the concentration of each pigment varied significantly. On average of the two years, the chlorophyll a concentration varied from 4800 to 7300 microg/100 g fresh weight, the chlorophyll b concentration from 2100 to 2800 microg/100 g fresh weight, the (all-E)-lutein concentration from 1200 to 1900 microg/100 g fresh weight, and the (all-E)-beta-carotene concentration from 300 to 490 microg/100 g fresh weight in the processed pea cultivars. These differences in pigment concentration between the investigated cultivars are discussed in relation to maturity, product color and nutritional quality.     

氮肥水平对鲁梅克斯K-1杂交酸模氮素利用和氮素平衡的影响

鲁梅克斯K 1杂交酸模对氮素的吸收与施氮量的关系可用线性加平台模型描述。植株氮素来自肥料氮的比例Ndff随施氮线性增加 ,但利用率随施氮量先上升后下降 ,变化范围从 32 1 1 %～ 42 78% ,在推荐施氮N3(6 0 0Nkg·hm- 2 )水平下为42 78%。根对肥料氮的截留率与植株利用率的趋势相似 ,在 1 9 87%～ 2 4 37%范围变化 ,植株吸收率在 51 97%～ 6 7 1 5%范围变化。肥料氮的土壤残留率基本不变 ,平均为 2 1 89%。氮肥回收率开始时随施氮无显著变化 ,N3处理后迅速下降 ,损失率趋势与之相同 ,但方向相反 ,在 9 40 %～ 2 5 93%范围变化。在分茬施肥的模式下 ,不同施氮下的土壤全氮不随茬次显著变化 ,但施氮对土壤全氮水平有显著影响 ,土壤全氮的全年周转率随施氮在范围 4 6 7%～ 9 39%变化     

Effect of Chronic Nitrogen Additions on Soil Nitrogen Fractions in Red Spruce Stands

The responses of temperate and boreal forest ecosystems to increased nitrogen (N) inputs have been varied, and the responses of soil N pools have been difficult to measure. In this study, fractions and pool sizes of N were determined in the forest floor of red spruce stands at four sites in the northeastern U.S. to evaluate the effect of increased N inputs on forest floor N. Two of the stands received 100 kg N ha^-1 yr^-1 for three years, one stand received 34 kg N ha^-1 yr^-1 for six years, and the remaining stand received only ambient N inputs. No differences in total N content or N fractions were measured in samples of the Oie and Oa horizons between treated and control plots in the three sites that received N amendments. The predominant N fraction in these samples was amino acid N (31-45% of total N), followed by hydrolyzable unidentified N (16-31% of total N), acid-soluble N (18-22% of total N), and NH₄ ⁺ (9^-13% of total N). Rates of atmospheric deposition varied greatly among the four stands. Ammonium N and amino acid N concentrations in the Oie horizon were positively related to wet N deposition, with respective r2 values of 0.92 and 0.94 (n = 4, p < 0.05). These relationships were somewhat stronger than that observed between atmospheric wet N deposition and total N content of the forest floor, suggesting that these pools retain atmospherically deposited N. The NH₄ ⁺ pool may represent atmospherically deposited N that is incorporated into organic matter, whereas the amino acid N pool could result from microbial immobilization of atmospheric N inputs. The response of forest floor N pools to applications of N may be masked, possibly by the large soil N pool, which has been increased by the long-term input of N from atmospheric deposition, thereby overwhelming the short-term treatments.     

Effect of tannins from Quercus suber and Quercus coccifera leaves on ethanol-induced gastric lesions in mice

The gastroprotective effects of 70% acetone extracts of Quercus suber and Quercus coccifera leaves and of tannins (pedunculagin, castalagin, phillyraeoidin A, and acutissimin B) purified from these extracts were examined in the mouse using the ethanol-induced gastric ulcer model. Both extracts (25, 50, and 100 mg/kg), given orally, prevented the formation of ethanol-induced lesions in the stomach. The percent protection varied between 68 and 91%. Purified tannins (50 mg/kg) were also effective in protecting the stomach against ethanol, and the percent protection varied from 66 to 83%. Castalagin was the most potent. Both extracts and all of the tannins tested (10, 25, and 50 microg/mL) strongly inhibited (55-65%) the lipid peroxidation of rabbit brain homogenate. These results suggest that the gastroprotective effects of extracts of Q. suber and Q. coccifera leaves and the purified tannins in this experimental model are related to their anti-lipoperoxidant properties.     

Gravimetric determination of ash in foods: NMKL collaborative study

A gravimetric method for the determination of ash was collaboratively studied in 14 laboratories. The food is ashed at 550 degrees C to constant weight and the ash is determined by weighing. Seven samples of various food commodities with estimated ash contents varying between low and high (0.07-8.0 g/100 g) were included in the study. The relative standard deviations for reproducibility varied, ranging from 1.0 and 1.3 for ash contents of 7.2 and 8.0 g/100 g, to 11 +/- 1% for low ash contents of 0.07 and 0.27 g/100 g.