Effect of sheep digestive tract on the recovery and germination of seeds of fifteen leguminous plants in the northern Xinjiang region,China

为揭示北疆地区豆科植物种子对绵羊消化道作用的响应, 采集了北疆地区天然草地中常见的15种豆科植物种子。首先测定种子的长、宽、厚和质量, 并计算种子的形状指数。其次, 用种子饲喂绵羊, 收粪试验在种子摄食后的第6、12、24、36、48和72 h进行, 测定种子经绵羊消化道作用后的回收率、种子在绵羊消化道内的平均滞留时间以及消化道作用前后种子的萌发行为, 并研究了种子大小及形状指数对平均滞留时间和种子回收率的影响。结果如下: 15种植物种子质量在1.50-37.68 mg之间, 形状指数在0.001-0.12之间, 均为中等或较大类型的球(圆)形种子; 种子被绵羊采食后的排放动态符合高斯模型: Y = 0.02 + 0.74e ^{-0.5(( X - 29.61)/9.41)2}, 种子排放高峰期集中在采食后的24-36 h时间段内; 种子回收率最大的是洋甘草(Glycyrrhiza glabra)(39.25%), 最小的是草木犀(Melilotus officinalis)(4.28%); 平均滞留时间最长的是草木犀(37.19 h), 最短的是新疆棘豆(Oxytropis sinkiangensis)(22.33 h); 种子回收率与种子大小和形状指数之间分别具有符合形如Y = 6.45 + 2.05X - 0.04X ²和Y = 2.59 + 36.97e ^{-24.47 X}的函数关系模型; 平均滞留时间与种子大小和形状指数之间分别具有符合形如Y = 12.48 + 37.44e ^{-0.07 X}和Y = 3.93 + 2055.33X - 21757.99X ²的函数关系模型, 此结果表明, 较大、较小和形状不规则的豆科种子较易被绵羊消化和排泄。经绵羊消化道作用后, 多叶锦鸡儿(Caragana pleiophylla)种子的萌发率由消化前的96.22%显著降低至35.17%, 野火球(Trifolium lupinaster)和狐尾黄耆(Astragalus alopecurus)种子萌发率和消化前相比差异不显著, 其余12种种子的萌发率均显著提高(p < 0.05)。     

北疆地区15种豆科植物种子对绵羊消化道作用的响应北大核心CSCD

为揭示北疆地区豆科植物种子对绵羊消化道作用的响应,采集了北疆地区天然草地中常见的15种豆科植物种子。首先测定种子的长、宽、厚和质量,并计算种子的形状指数。其次,用种子饲喂绵羊,收粪试验在种子摄食后的第6、12、24、36、48和72 h进行,测定种子经绵羊消化道作用后的回收率、种子在绵羊消化道内的平均滞留时间以及消化道作用前后种子的萌发行为,并研究了种子大小及形状指数对平均滞留时间和种子回收率的影响。结果如下:15种植物种子质量在1.50–37.68mg之间,形状指数在0.001–0.12之间,均为中等或较大类型的球(圆)形种子;种子被绵羊采食后的排放动态符合高斯模型:Y=0.02+0.74e^(–0.5((X–29.61)/9.41)~2),种子排放高峰期集中在采食后的24–36 h时间段内;种子回收率最大的是洋甘草(Glycyrrhiza glabra)(39.25%),最小的是草木犀(Melilotus officinalis)(4.28%);平均滞留时间最长的是草木犀(37.19 h),最短的是新疆棘豆(Oxytropis sinkiangensis)(22.33 h);种子回收率与种子大小和形状指数之间分别具有符合形如Y=6.45+2.05X–0.04X^2和Y=2.59+36.97e^(–24.47X)的函数关系模型;平均滞留时间与种子大小和形状指数之间分别具有符合形如Y=12.48+37.44e–0.07X和Y=3.93+2055.33X–21757.99X^2的函数关系模型,此结果表明,较大、较小和形状不规则的豆科种子较易被绵羊消化和排泄。经绵羊消化道作用后,多叶锦鸡儿(Caragana pleiophylla)种子的萌发率由消化前的96.22%显著降低至35.17%,野火球(Trifolium lupinaster)和狐尾黄耆(Astragalus alopecurus)种子萌发率和消化前相比差异不显著,其余12种种子的萌发率均显著提高(p<0.05)。     

多鳞四须鲃耗氧率、排氨率和窒息点的初步研究

控制水温在(20±0.5)℃条件下,采用Winkler法和奈氏试剂法分别测定水中的溶氧含量和氨氮含量,通过比较流水呼吸室进、出口水中的溶解氧和氨氮含量之差以确定多鳞四须鲃(Barbodes schwanenfeldi)的耗氧率、排氨率及窒息点.结果表明,多鳞四须鲃耗氧率随体重增加而减小,关系式为Y=0.24X^-0.09(R²=0.9028);随放养密度的增大而减小,关系式为Y=-0.029X+0.3301 (R²=0.9291).排氨率随体重的增加而减小,关系式为Y=-0.0008X+0.2433 (R²=0.9817);随放养密度的增大而增加,关系式为Y=-0.050X+0.4979 (R²=0.9889).多鳞四须隹巴晚间(18:00～4:00)的耗氧率明显高于白天(6:00-1:00),排氨率则相反,白天的排氨率相对较高,表明多鳞四须鲃巴属于"昼伏夜出"型鱼类.多鳞四须啬巴的窒息点为1.2572mg·L^-1,耐氧性较差.     

鮸形态性状与体质量的关系

为了研究鮸的形态性状与体质量之间的关系,测量了524尾12月龄左右鮸的体质量(Y, g)和8个形态性状(cm),包括全长(X₁)、体长(X₂)、头长(X₃)、躯干长(X₄)、尾长(X₅)、尾柄长(X₆)、尾柄高(X₇)和体高(X₈).采用相关分析、回归分析、通径分析以及模型拟合等方法对其进行分析.结果表明: 鮸所有性状两两之间存在极显著正相关关系,相关系数在0.834～0.941.经共线性诊断排除了体长这一具有严重共线性的性状后,采用逐步引入-剔除法进行多元回归并进行显著性检验,成功筛选出全长(X₁)、躯干长(X₄)、尾柄高(X₇)和体高(X₈)4个统计检验极显著的形态性状,并建立多元回归方程:Y ＝-444.188 +7.943X₁ +12.861X₄ +38.254X₇ + 42.722X₈.通径分析结果显示,4个形态性状中,体高对体质量的直接作用最大(通径系数=0.351),全长次之(通径系数=0.335).对全长和体高与体质量之间的函数关系进行曲线模型拟合得出,在6个拟合模型中,幂函数模型拟合效果最好,方程为:y=0.013 x^2.891(全长); y=2.028 x^2.751(体高).经适合性检验得知,全长比体高通过幂函数对体质量的预测效果更好.研究结果可为鮸的形态性状在选择育种中的有效利用提供重要参考.     

不同产地姜黄属植物中姜黄素类成分及矿质元素分析

以福建泉州地区种植的12个姜黄(Curcuma longa)和莪术(Curcuma zedoaria)种质的成熟根茎为试材, 采用正交设计法优化姜黄素(CCM)、单脱甲氧基姜黄素(DMC)和双脱甲氧基姜黄素(BDMC)的提取工艺条件, 比较不同产地姜黄属种质的3种姜黄素类化合物和16种矿质元素的含量。结果表明, 姜黄素类化合物提取工艺为: 100%甲醇, 1:5 (g·mL^-1)固液比, 超声提取2分钟, 提取率达到最高值。CCM、DMC和BDMC的最大吸收波长分别为424、418及414 nm; 回归方程分别为Y=0.170 3X+0.024 3 (CCM), Y=0.173 8X+0.041 (DMC), Y=0.140 6X+0.051 4 (BDMC)。GY03种质中CCM、DMC和BDMC含量分别为1.23%、1.22%与1.50%, 总姜黄素类含量最高, 达3.95%; GY01种质的总姜黄素次之(为3.82%); GY03和GY01可在栽培地推广种植; 12个姜黄属种质的16种矿质元素中, 以Mg、Mn、Al、Fe和Zn含量较为丰富。     

不同产地姜黄属植物中姜黄素类成分及矿质元素分析

以福建泉州地区种植的12个姜黄(Curcuma longa)和莪术(Curcuma zedoaria)种质的成熟根茎为试材, 采用正交设计法优化姜黄素(CCM)、单脱甲氧基姜黄素(DMC)和双脱甲氧基姜黄素(BDMC)的提取工艺条件, 比较不同产地姜黄属种质的3种姜黄素类化合物和16种矿质元素的含量。结果表明, 姜黄素类化合物提取工艺为: 100%甲醇, 1:5 (g·mL^-1)固液比, 超声提取2分钟, 提取率达到最高值。CCM、DMC和BDMC的最大吸收波长分别为424、418及414 nm; 回归方程分别为Y=0.170 3X+0.024 3 (CCM), Y=0.173 8X+0.041 (DMC), Y=0.140 6X+0.051 4 (BDMC)。GY03种质中CCM、DMC和BDMC含量分别为1.23%、1.22%与1.50%, 总姜黄素类含量最高, 达3.95%; GY01种质的总姜黄素次之(为3.82%); GY03和GY01可在栽培地推广种植; 12个姜黄属种质的16种矿质元素中, 以Mg、Mn、Al、Fe和Zn含量较为丰富。     

吉林省长白山区胡桃楸天然次生混交林立地指数模型

依据吉林省长白山胡桃楸天然次生混交林12个典型区域的坡向、坡位分布,结合胡桃楸龄级,布设样地109块,以年龄-树高数据为材料,编制了吉林省东部山区胡桃楸天然次生混交林立地指数表.结果表明: 应用3倍树高标准差法剔除异常数据,最终得到80块379对胡桃楸不同龄级的年龄与树高数据,运用7个数学模型进行比较,确定了单形立地指数导向曲线方程式: H=28.0181(1-e^-0.0341A)^1.0503,决定系数R²为0.85,残差平方和为0.89,基准年龄为50年,指数级距为2 m,得到了16～28 m的7条立地指数曲线.根据不同立地类型,建立了多形立地指数模型,幂函数拟合效果较好,即H=B₀t^B1,其中B₀=10^-9e^0.9213SI,B₁=-0.2139SI+5.6183,最终得到了多形立地指数模型方程式H=10^-9e^0.9213SIt^{-0.2139SI+5.6183}.指数级差法和落点检验法对2种立地指数模型的精度检验表明,多形立地指数的精确度较高,能够准确地反映胡桃楸不同立地类型间树高生长的差异,可用于吉林省长白山区胡桃楸天然次生混交林立地质量评价.     

胞质Ca2+参与外源H2S促进盐碱胁迫下裸燕麦种子萌发

硫化氢（Hydrogen sulfide,H₂S）是植物新型气体信号分子,钙离子（Calcium,Ca²⁺）为重要的第二信使,两者在植物逆境响应中分别发挥着重要作用。为明确胞质Ca²⁺在外源H₂S促进盐碱胁迫下作物种子萌发中的作用,以裸燕麦（Avena nude）为材料,采用培养皿培养,以混合盐碱（NaCl、Na₂SO₄、Na₂CO₃、NaHCO₃的摩尔比为12：8：1：9）模拟甘肃裸燕麦种植地盐碱环境,蒸馏水为对照,测定了胞外Ca²⁺螯合剂乙二醇-双-（2-氨基乙醚）四乙酸（EGTA）、质膜Ca²⁺通道阻断剂氯化镧（LaCl₃）、液泡Ca²⁺释放抑制剂钌红（RR）和内质网钙泵阻断剂毒胡萝卜素（Thaps）分别与H₂S供体硫氢化钠（NaHS）共处理下种子的发芽势、发芽率、发芽指数、活力指数、平均发芽速率、胚根长和胚芽长7个发芽指标,利用隶属函数分析方法综合评价胞质Ca²⁺对H₂S缓解盐碱胁迫抑制种子萌发的影响。结果表明,随着盐碱胁迫浓度增大,裸燕麦种子的发芽势、发芽率、发芽指数、活力指数、平均发芽速率、胚根长和胚芽长显著下降。与对照相比,15~75 mmol·L^-1盐碱胁迫导致裸燕麦种子萌发的隶属函数综合评价值（D）显著降低,30 mmol·L^-1盐碱胁迫下D值下降了73.1%;100~1 000 μmol·L^-1 NaHS不同程度提高了裸燕麦种子萌发的D值,且100 μmol·L^-1 NaHS缓解30 mmol·L^-1盐碱胁迫下D值下降的作用最大;EGTA、LaCl₃和RR均显著逆转了100 μmol·L^-1 NaHS对30 mmol·L^-1盐碱胁迫下D值下降的缓解作用,而Thaps对NaHS的作用无显著影响。表明胞质Ca²⁺参与外源H₂S促进盐碱胁迫下裸燕麦种子萌发的信号传导过程,且胞质Ca²⁺主要来源于胞外Ca²⁺的内流和液泡中Ca²⁺的释放。     

混合盐碱胁迫对小白菜种子萌发的影响

用不同浓度的NaCl、Na₂SO₄、NaHCO₃和Na₂CO₃混合液对小白菜(Brassica chinensis L.)种子进行种子萌发试验,观察小白菜种子在不同浓度盐碱胁迫下的发芽率和发芽指数。结果表明,在混合盐碱胁迫下,小白菜种子的发芽率、发芽势、发芽指数和活力指数均随pH值增大和盐浓度的升高呈下降趋势,且各萌发指标与盐浓度的相关系数明显大于pH值,可见小白菜种子发芽受盐浓度的影响更大。低浓度(50mmol·L^-1)盐碱胁迫对小白菜种子萌发影响不大,高浓度(200mmol·L^-1)盐碱胁迫下小白菜的种子萌发受到严重影响。     

青藏高原东缘61种常见木本植物种子萌发特性及其与生活史的关联

为了评价亚高山地带木本植物种子萌发对策及其与生活史关联, 该文对青藏高原东缘61种常见木本植物的种子萌发特征以及种子萌发与种子大小、扩散方式、海拔及生境的关系进行了调查分析。结果表明: 1) 61种植物的种子萌发率呈现偏斜、双峰分布。6种植物(9.8%)的种子萌发率大于80%, 13种(21.3%)的萌发率在60%~80%之间, 9种(14.8%)的萌发率在40%~60%之间, 8种(13.1%)的萌发率在20%~40%之间, 25种(41%)的萌发率小于20%, 其中8种植物的种子萌发率为零, 显示了该生境中木本植物的种子以休眠、低萌发率或连续稳定的萌发对策占优势, 以避免不利的环境因素。2)种子扩散方式是决定61种木本植物种间萌发率变异(R² = 24.1%, p < 0.001) 和萌发开始时间变异(R ²= 21.3%, p < 0.01) 的主要因素; 种子大小、母体植株的海拔和生境对种子萌发率和萌发开始时间几乎没有影响(p > 0.05); 风扩散的种子比脊椎动物扩散和无助扩散的种子有更高的萌发率(F = 9.219, p < 0.001) 和较早的萌发开始时间(F = 6.772, p < 0.01)。说明植物生活史特征如种子萌发与扩散方式之间存在固有而紧密的联系, 扩散能力强的种子(如风扩散)由于能散布到较远而空旷的生境, 可能避免了各种有害因素或个体竞争, 因而种子以较强的萌发能力进行拓殖; 扩散能力弱的种子(如无助扩散)由于其散布距离较近, 种子以休眠或降低萌发的方式来避免个体或同胞竞争以及各种有害因素, 以获得最大的生态利益并确保物种延续。     

濒危树种闽楠种子和幼苗生态学研究

从1995至1998年,通过种子收集器布设、不同程度圈围的样方处理、实验室和野外发芽实验、相邻格子样方调查和土壤中种子的筛选等一系列方法,对福建罗卜岩闽楠种子质资源保护区内闽楠为优势的常绿阔叶林群落中闽楠种群的果实、种子库、种子散布、果实／种子捕良、种子萌发和幼苗存活等进行了研究。结果表明：1995至1996年果实量为116个／m^2,成熟高峰期在1996年1月中旬。1997年至1998年为103个/m^2,成熟高峰期在1997年12月中旬。1997年至1998年,绝大部分（90．1％）的果实直接从母树上掉落,低于9．5％的果实由鸟类传播。实验室的种子发芽率为93％,而在野外仅为12％。野外发芽率低多由种子霉烂引起。闽楠的种子寿命较短,其种子在次年4月初开始萌发,7月之后地面种子即丧夫活力。动物捕食不仅影响种子的存活,同时也影响幼苗的死亡率,未经圈围与样地中被取食的果实和幼苗数量有显著差异。在新形成的林窗中或远离母树均降低了果实的迁移和幼苗的死亡率。但各因素交互作用有所不同。密度相关效应发生在2－3个月的幼苗阶段,之后,密度高低对果实被取食和幼苗死亡没有显著的影响。这些结果表明,闽楠种子和幼苗经历较大的环境压力,即在高湿度生境中母树树冠下的种子不仅易受到土壤病原菌的感染,同样容易遭受动物所捕食,从而导致较低的野外种子发芽率和幼苗存活率。这是闽楠致濒的重要原因之一。     

The Use of Seeds by a Twig-Dwelling Ant on the Floor of a Tropical Rain Forest

The role of Pheidole praeses , a twig-nesting ant inhabiting the floor of the Brazilian Atlantic forest, as potential secondary seed disperser was investigated. A total of 901 seeds (20 morphospecies) were retrieved from 50 nests, most of them intact and able to germinate. Considering the abundance of Pheidole species and the evidence pointing to their potential as seed dispersers, these ants may be important determinants of the recruitment of small-seeded plants in tropical forests.
Abstract in Portugese is available at http://www.blackwell-synergy.com/loi/btp .     

金钟藤种子低萌发率原因探讨

金钟藤种子在室内萌发率很低,为进一步探讨金钟藤种子的特性,阐明其种子萌发率低的主要原因,对金钟藤种皮的透水性、种子解剖结构、种子活力和种子内源抑制物的生物测定进行了研究。结果表明:金钟藤种皮透水性较差,完整种子比破皮种子吸水达到最高水平慢38h;种子空瘪粒多,占所有种子的30%;种子活力较低,平均活力仅为35%;金钟藤种子甲醇粗提液对白菜种子萌发率、根长和芽长均有较强的抑制作用,其浸提液浓度在25mg/mL时,严重抑制白菜种子萌发和生长,即金钟藤种子内部含有较高的内源抑制物质。金钟藤种子萌发率低,表明其近年来突发性蔓延成灾主要不是由种子生成新个体造成的,导致其蔓延成灾的关键因素还需要进一步深入研究。     

贵州茂兰喀斯特森林中华蚊母树群落种子库及其萌发特征

茂兰喀斯特森林中华蚊母树群落900m^2的样地内共有种子植物59种。其中19种主要植物已进人繁殖阶段,每年产生成熟种子238．8粒／m^2,种子雨量达351．1粒／m^2。其中对群落更新有作用的成熟有效种子数为150．8粒／m^2。萌发前种子库中有活力种子41种2642．O粒／m^2。其中现存植物种子19种。萌发后种子库中有活力种子28种2504．5粒／m^2,其中现存植物种子6种。葫发前后种子库的差异主要在于枯枝落叶层的种子含量。当年产生的种子大多数位于种子库的枯落叶层中,随时间推移,寿命较长的种子逐渐移到土壤层中。群落演替前期各阶段产生的种子全部位于土壤层里。萌发前种子库与现存群落的相似性大于萌发后种子库。群落内有19种主要植物繁殖产生种子,并在萌发前的种子库中有活力种子存在,群落更新潜力很好。群落遭受破坏的季节不同。其恢复潜力也不一样。群落内平均每年萌发出苗14种54．2株／m^2,当年存活24．5株／m^2,群落更新较好。     

Effect of Temperature Regimes on Germination of Dimorphic Seeds of Atriplex prostrata

Dimorphic seeds of Atriplex prostrata were removed from cold dry storage monthly over a one year period to test for fluctuations in seed dormancy and germination rate. For each seed type, four replicates of 25 seeds were exposed to four alternating night/day temperature regimes mimicking seasonal fluctuations in Ohio: 5/15 °C; 5/25 °C; 15/25 °C and 20/35 °C with a corresponding 12-h photoperiod (20 μmol m⁻² s⁻¹; 400 – 700 nm). We found a significant three-way interaction of seed size, temperature and month for both percent germination and the rate of germination. Large seeds showed the greatest germination at the 20/35 °C and 5/25 °C temperature regimes and small seeds at the 5/25 °C regime. Large seeds had greater germination at all temperatures as compared to small seeds. Large seeds had the fastest germination rates at 20/35 °C followed by 5/25 °C whereas small seeds had the fastest rates at 5/25 °C followed by 20/35 °C. This revised version was published online in July 2006 with corrections to the Cover Date.     

Seed Germination Biology of the Narrowly Endemic Species Lesquerella stonensis (Brassicaceae)

Abstract Lesquerella stonensis (Brassicaceae) is an obligate winter annual endemic to a small portion of Rutherford County in the Central Basin of Tennessee, where it grows in disturbed habitats. This species forms a persistent seed bank, and seeds remain viable in the soil for at least 6 years. Seeds are dormant at maturity in May and are dispersed as soon as they ripen. Some of the seeds produced in the current year, as well as some of those in the persistent seed bank, afterripen during late spring and summer; others do not afterripen and thus remain dormant. Seeds require actual or simulated spring/summer temperatures to come out of dormancy. Germination occurs in September and October. Fully afterripened seeds germinate over a wide range of thermoperiods (15/6–35/20°C) and to a much higher percentage in light (14 h photoperiod) than in darkness. The optimum daily thermoperiod for germination was 30/15°C. Nondormant seeds that do not germinate in autumn are induced back into dormancy (secondary dormancy) by low temperatures (e.g., 5°C) during winter, and those that are dormant do not afterripen; thus seeds cannot germinate in spring. These seed dormancy/ germination characteristics of L. stonensis do not differ from those reported for some geographically widespread, weedy species of winter annuals and thus do not help account for the narrow endemism of this species.     

A comparative study of seed yield parameters in Arabidopsis thaliana mutants and transgenics

Because seed yield is the major factor determining the commercial success of grain crop cultivars, there is a large interest to obtain more understanding of the genetic factors underlying this trait. Despite many studies, mainly in the model plant Arabidopsis thaliana, have reported transgenes and mutants with effects on seed number and/or seed size, knowledge about seed yield parameters remains fragmented. This study investigated the effect of 46 genes, either in gain- and/or loss-of-function situations, with a total of 64 Arabidopsis lines being examined for seed phenotypes such as seed size, seed number per silique, number of inflorescences, number of branches on the main inflorescence and number of siliques. Sixteen of the 46 genes, examined in 14 Arabidopsis lines, were reported earlier to directly affect in seed size and/or seed number or to indirectly affect seed yield by their involvement in biomass production. Other genes involved in vegetative growth, flower or inflorescence development or cell division were hypothesized to potentially affect the final seed size and seed number. Analysis of this comprehensive data set shows that of the 14 lines previously described to be affected in seed size or seed number, only nine showed a comparable effect. Overall, this study provides the community with a useful resource for identifying genes with effects on seed yield and candidate genes underlying seed QTL. In addition, this study highlights the need for more thorough analysis of genes affecting seed yield.     

Influence of drought and heat stress,applied independently or in combination during seed development,on qualitative and quantitative aspects of seeds of lentil (Lens culinaris Medikus) genotypes,differing in drought sensitivity

Terminal droughts, along with high temperatures, are becoming more frequent to strongly influence the seed development in cool‐season pulses like lentil. In the present study, the lentil plants growing outdoors under natural environment were subjected to following treatments at the time of seed filling till maturity: (a) 28/23 °C day/night temperature as controls; (b) drought stressed, plants maintained at 50% field capacity, under the same growth conditions as in a; (c) heat stressed, 33/28 °C day/night temperature, under the same growth conditions as in a; and (d) drought + heat stressed, plants at 50% field capacity, 33/28 °C day/night temperature, under the same growth conditions as in (a). Both heat and drought resulted in marked reduction in the rate and duration of seed filling to decrease the final seed size; drought resulted in more damage than heat stress; combined stresses accentuated the damage to seed starch, storage proteins and their fractions, minerals, and several amino acids. Comparison of a drought‐tolerant and a drought‐sensitive genotype indicated the former type showed significantly less damage to various components of seeds, under drought as well as heat stress suggesting a cross tolerance, which was linked to its (drought tolerant) better capacity to retain more water in leaves and hence more photo‐assimilation ability, compared with drought‐sensitive genotype.